Potassium (K) comes with a wide variety of complimentary cations and anions.  Sulfate and chloride (Cl) are the common anions.   Magnesium (Mg) is a semi-common cation commonly applied with K (K-Mag).  Sandy soils in the Columbia Basin (USA) have dropped in K to less than 100 ppm (NaHCO₃). Potatoes are a high demand  crop were annual uptake can exceed 600 kg ha^-1 and daily peak uptake exceed 20 kg ha-day^-1.  Chloride has long been associated with reduced specific gravity and competing with nitrate for uptake.  In this two year study we measured the consequences of K applications of up to 1400 kg ha^-1 both in the tuber and in above ground dry-matter.  Potassium chloride, sulfate and Mg-K fertilizers were applied at emergence.  Mg rates in excess of 1400 kg ha^-1 had no effect on potato yield or quality.  Potassium rate had little to no effect on nutrient concentration in the tubers.  Potassium rate had a negative effect on Ca and Mg concentration in the above ground dry-matter. Nitrate in petioles was decreased with increased KCl rate.  Yield response to K was dependent on year. Specific gravity was decreased with increased Cl rate.  

A triennial research project on irrigation water use was carried out on 40 farms in Tuscany, Central Italy, under the scientific and technical supervision of the University of Firenze and the financial support of the Agency for Development and Innovation in Agriculture and Forestry of the Tuscan Region (ARSIA). Project activity provided for the investigation of actual irrigation practice at different scale units. Micro-irrigation of annual and perennial crops was assessed on 18 fields (cropping units), according to a comprehensive approach including evaluation of site specific soil properties, crop characteristics across the growing cycle, climate water demand and crop evapotranspiration during the irrigation season, cultivation strategies, and irrigation system performance defined according to the low quarter Emission Uniformity parameter (EUlq). Actual seasonal irrigation supply (ASI) of each cropping unit was compared to calculated net irrigation requirement (NIR), and assessed according to the measured performance of the irrigation system.

ASI of annual crops exceeded NIR in most cases (82%), in a range from 3% to 158%. About half of the perennials (43%) was irrigated under stress conditions (from -33% to -70%), in excess the other 57% (from 26% to 167%). System EUlq varied from 50.3% to 90.4% and from 40.1% to 93.2% on annual and perennial crops respectively.

The average seasonal NIR, EUlq and ASI are 261 mm, 75.8% and 322 mm for annual crops, 281 mm, 74.6% and 300 mm for perennials. Average gross irrigation (AGI), calculated as average NIR/EUlq ratio, shows different cultivation strategies: yield maximization of annual crops (ASI~AGI), search for specific quality response of perennials by using deficit strategies (ASI<AGI). Due to several farmers’ typical attitudes towards the irrigation system, such as insufficient management and/or use exceeding the suggested technical lifetime, the fact remains that actual micro irrigation performance is by far below the potential in the project area.

The International Symposium on Soil and Plant Analysis (ISSPA) is the premier gathering and showcase event in soil and plant analysis. The previous Symposia were held in Fresno, California, USA (1989), Orlando, Florida, USA (1991), Olympia, Washington, USA (1993), Wageningen, Netherlands (1995), Bloomington, Minnesota, USA (1997), Brisbane, Queensland, Australia (1999), Edmonton, Alberta, Canada (2001), Somerset West, West Cape, South Africa (2003), Cancun, Mexico (2005), Budapest, Hungary (2007), and Santa Rosa, California, USA (2009). The author has the distinction of being the only scientist in the world to have participated in all the 11 Symposia: An ISSPA record!

In this paper, the author presents the history of the symposia since he participated in the Business Meeting of the Council on Soil Testing and Plant Analysis (now Soil and Plant Analysis Council) at the Annual Meetings of the American Society of Agronomy, the Crop Science Society of America, and the Soil Science Society of America in Anaheim, California, USA, November 27-December 2, 1988. This is where he learnt about the International Symposium on Soil Testing and Plant Analysis (now International Symposium on Soil and Plant Analysis) to be held in Fresno, California, USA onAugust 14-19, 1989. The purpose of the Symposium was to bring together agricultural and natural resource scientists from around the globe to share information on soil, plant, and water analysis for the purpose of efficient resource management and environmental protection.Fresno was chosen as the site due to its diverse and large agricultural industry. The paper concludes with information on the authors contributions to all the symposia.

Ayvalık olive variety comprises 25 % of olive groves located at the western Ege Region. It is a well known variety utilized for oil extraction and green pickling. The research work is carried out on 19 years old olive trees in 2009 and 2010 at Kemalpaşa experimental plot of İzmir Olive Research Institute to test the effect of foliar boron and calcium applications, as combined or alone. Boron is applied as 0.5 % borax (Na₂B₄O₇.10H₂O) in April, prior to bloom and in June when fruit are 3-4 mm in diameter. Calcium is applied as 0.5 % calcium nitrate Ca (NO₃)2 in mid-June and in early July (pit hardening period). Control trees are treated with water on the dates of applications. Olive fruit samples are collected at monthly intervals and analyzed for average fruit weight, volume, and dry matter, oil, N, P, K, Ca and B contents. Total yield per tree is also calculated. The effects of tested treatments were investigated for two years, on on and off years. Results proved that combined applications of boron and calcium perfomed better. Calcium+boron treatments accelerated fruit boron levels compared to boron application alone due to synergistic effect of calcium. Similarly, oil contents were higher especially during the off year. No phytotoxic effect of Na was observed on trees treated with borax

Soil Potassium (K) moves by diffusion from soil minerals to the plant roots. Soil types with more clay or other readily releasing K minerals are known to buffer the soil solution and result in higher K supply. Conventional soil extractions measure the soil solution K and some proportion of the exchangeable or buffered K. The ion exchange membrane method, known as the Plant Root Simulator (PRS™) probe, was designed to be an integrated measure of the factors controlling K supply namely, soil solution K, diffusion path, and the mineral soil buffer power. The PRS™ probe uses the principle of ‘Donnan Exchange’ to attract and adsorb K ions from soil solution, creating a concentration gradient that results in more K release from buffering clay minerals. For over 20 years this technology has better explained K supply rates from many soil types in western Canada. One significant observation over time was that certain soil types possessing high proportions of 2:1 swelling clays consistently show a false positive for K deficiency as evidenced by field applied fertilizer omission strips. It was postulated that on these types of clay soils, the contribution of interlayer K was not effectively measured since sodium (Na), currently used as the PRS™ probe counter ion, has a large hydrated radius and could not exchange with interlayer K. This study shows that the cesium (Cs) ion, which has a smaller hydrated radius than Na, and reactive properties similar to K, can be more effective as a counter ion and may better assess the bioavailable K from heavy clay soils. Standard cation PRSTM-probes were treated with 0.001M Cs solution in order to achieve partial membrane saturation. Preliminary results from over 100 soils indicate that Cs:Na counter ion PRS™ probes exchanged more K from these heavy clay soils as compared to the standard Na PRSTM-probes. The K supply rate to the Cs:Na PRS™ probes increased by an average of 30%. Further studies are underway to validate this improvement in measuring bioavailable K by comparing both standard lab methods and K uptake by barley in a growth chamber experiment. Improving the ability of PRSTM-probes to simulate the mechanisms used by the plant to exchange and adsorb interlayer K will improve the management of all K-limited soils.

The objective of the study was to establish nitrogen precision management systems based soil Nmin (soil mineral N) test for basal N application and the plant N status diagnosis for topdressing application in North China Plain, where N application rates up to 600 kg N/ha. The field experiments were conducted in common farmer’s field and N experiment with 4 treatments of N0, N200, N400, N600 kg N/ha/y. Digital images were acquired using an Olympus 2100UZ. Indexes of N status diagnosing and recommendation N rates were established based on the relationship between digital imaging and crop N status. The results showed that average base application rates of 80 kg N/ha was needed for 7500kg/ha of wheat yield, which range from 0 to 139 kg N/ha according to spatial variation of soil nitrate contents. The normalized green intensity G/(R+G+B) at wheat stem elongation stage and normalized blue intensity B/(R+G+B) at maize six leaves stage, showing best correlations with N status, could be as the indicators to recommend N rates for wheat and maize. 3 levels of Surplus, Optimum and Deficient of wheat N status were classified according to 0.392~0.405, 0.402~0.422, 0.412~0.444 of G/(R+G+B), recommended topdressing N were 0, 60 and 90 kg N/ ha respectively. 4 levels of Surplus, Optimum, Deficient and serious deficient of wheat N status were classified according to 0.241-0.247, 0.216-0.237, 0.201-0.220 and 0.18-0.200 of B/(R+G+B), recommended topdressing N were 50,100,150 and 200 kg N/ha respectively. Demonstration of the practices can save N 34.6% for wheat and 62.4% for maize without yield reduction compare to farmers traditional N used

Our study compares the performances of several statistical methods for deriving spatial models of soil parameters in the surface horizon. The applications were carried out within a 186 km² hydrographic basin situated in eastern Romania. After data quality check, statistical models were computed from a sample of approximately 180 soil profiles, scattered in the eastern half of the basin, the actual number varying from one soil parameter to another. An independent sample of 50 soil profiles was used for interpolation validation and another independent sample of same size was used to validate the results within the extrapolation area (the western half of the basin). We tested the performances of kriging, linear regression, geographically weighted regression, regression trees and regression-kriging for computing spatial models of physical (soil depth, granulometric fractions) and chemical (pH, occurrence depth of calcium carbonates, content of humus, total nitrogen, mobile potassium, mobile phosphorus and base saturation) soil parameters. The predictors included X and Y coordinates of soil profiles, geomorphometrical parameters (slope, aspect, wetness index, terrain curvature), derived from a 10x10 m digital elevation model, climate parameters (mean annual temperatures, precipitations and global radiation), the main soil types, land use and surface lithology. The results show that the optimum statistical method varies from one parameter to another. Parameters such as soil depth, depth to calcium carbonates, pH are better related to terrain variables and therefore may be approached regression analysis and regression-kriging, while parameters such as humus and total nitrogen content are better modeled using the local approach of kriging.

Nutrient balance is one of the indicators of sustainability of production systems. Sustainable farming is based on balanced nutrient management, i.e. inputs = outputs. For nutrient balance calculation in agricultural sector is necessary to observe a lot of factors - nutrient inputs (nutrients in fertilizers, atmospheric deposition, sewage sludge, nitrogen fixation, seeds and planting material, etc.) and on the other hand nutrient outputs (nutrients uptake by main product and by-product, leaching). Central Institute for Supervising and Testing in Agriculture provides in the Czech Republic the net of long-term field experiments in different soil and climate conditions. These experiments have a few combinations of application nutrients levels in regular crop rotation. Results from long-term experiments are optimal background for nutrient balance calculation and next determination of optimal nutrient management for sustainable crop production and their good quality in certain cropping region. Simultaneously nutrient balance calculation in connection with soil testing results is necessary base for precision farming.

    The objectives of this study were: a) the evaluation whether the P supplying power of soils, as assessed by Plant Root Simulator (PRS)^TM-probes, constitutes a reliable index of bioavailable P in calcareous soils, b) the examination whether pig compost addition to calcareous soils increases their P supplying power, P uptake by the crop and yield. The study was conducted in a pot experiment with 14 calcareous soils and involved control, test and treated with compost soils in which rye grass was grown and harvested every month. Three biomass cuts were obtained and P uptake, P concentration in the biomass and biomass yields were determined.

   Correlations of P uptake or P concentration in the biomass versus P supplying power gave statistically significant coefficients of determination (p≤ 0.01) which explained 75-88 and 87-92% of the variability of P uptake and P concentration, respectively. The relation between biomass yields and P supplying power of soils obeyed satisfactorily the Mitscherlich-Bray growth function permitting the establishment of a “critical point” of P supplying power which was about 5 μg P/resin surface area/15 day. These results provide strong evidence that the P supplying power of soils, as assessed by PRS^TM-probes, is a reliable index of bioavailable P in calcareous soils and even more reliable than the one determined by the conventional method of Olsen.

    Compost addition to soils had a beneficial effect because it increased their P supplying power, P uptake by the crop and biomass yields but the P supplying power of the treated soils did not correlate with P uptake and P concentration in the biomass. Although this discrepancy could not be explained by the data at hand, it remains certain that pig manure compost increased yields and it might not only complement but also substitute P fertilization. 

In last decades the olive production has been managed with fertilization techniques as fertigation. To adequate a correct dosification of fertilizers, the growers need fast and efficient techniques of nutrient diagnosis, such as combining soil, leaf and sap analysis.
The present work is focused on the application of all these nutritional tools to evaluate the potassium requirements of olive trees (Olea europea L.) cv. Picual in Jaen (Spain) during two years with a clay-silt soil and water from Guadalquivir river. Two experimental areas were selected (A) and (S), (A) with a plant density of 250 olive trees 15 to 17 year old per hectar and (S) with 140 olive trees 30 to 35 years old per hectar. Each experimental area was divided in two, control with fertigation (A1 and S1), and fertigation plus additional potassium fertilization with foliar spray (A2 and S2). Foliar and fruit analysis were useful to estimate the sink effect for potassium, increasing its concentration in fruit during ripenning. Sap analysis show significant increases of potassium in the second year of experiment, since an adequate supply of potassium during first year by fertigation. Sap is a material much more sensitive and dynamic than leaf analysis, and it allow us to know the nutrient reservoir of potassium of the tree after an adequate fertilization with this nutrient.

After two years using potassium foliar spray plus fertigation no significant differences were found. Consequently foliar spray is not useful when an adequate fertigation is been developed, although it can be used when this fertilization system is not implemented.
The olive production and quality (polyphenol levels) were significantly higher in the (S) experimental area, although no differences were obtained with additional potassium spray. Sap analysis is an excellent tool to evaluate nutritional needs of olive trees and to describe the potassium fate in the plant.

Surface NIR reflectance of bare soil has been used to infer top soil properties such as organic matter, soil texture, water content, salinity and crop residue cover. With the advent of mobile multispectral sensors, data on soil NIR reflectance can be easily obtained in an attempt to quantify the spatial distribution of soil properties within fields. Mapping of soil properties can be ultimately used as a tool for the implementation of site-specific management practices. In this study, a Crop Circle ground-sensor was used to map soil NIR reflectance in three 10-ha fields of differing soil category and texture ranging from sandy clay loam to clay that were located in different sections of the east Thessaly Plain. The produced NIR maps were used to delineate each field into distinct management zones. Soil samples were randomly taken within each management zone and analyzed in the laboratory for soil organic matter, total C and N content, their isotopic composition, carbonate content, nitrate content, pH, electrical conductivity. Results are presented on the correlation of sensor NIR reflectance with NIR reflectance from satellite imagery, soil organic matter and carbonate content. These results indicated that soil NIR reflectance can be used to characterize and map soil organic matter and the extent of erosion in larger sections of the Thessaly Plain independent of differences in soil category and soil properties.

The measurement of soil CO₂ respiration provides a gauge of biological soil fertility, but rapid and accurate means to measure respiration and to derive estimates of potential C + N mineralization are lacking. The Solvita® test was introduced recently and is based on measuring the 24hr CO₂ –burst following rehydration of dried soils. Rapid rewetting of soils causes a flush of CO₂ that corresponds closely to soil microbial biomass. In laboratory incubation-mineralization studies short-term flush of CO₂ correlates closely to 3d, 7d and 28d basal soil respiration. Mineralization of N in this period closely matches the yield of CO₂ following rewetting. Since incubations of soil for 1 to 2-weeks to determine potential mineralization are considered too costly for practical application, the Solvita 24-hour test offers commercial soil laboratories the opportunity to provide economical tests of soil microbial biomass. In America, the ALP program has accepted Solvita as a provisional test and 6 commercial laboratories are evaluating it during 2011. In this study we compare soils from various soil sampling programs, including ALP proficiency test programs, organic matter rate studies, and commercial organic growing where successive applications of compost with multiple-cropping are employed to release organic-N to available form. Solvita® provided a high level of correspondence to applied organic matter, it also correlated positively to Walkley-Black (digestible carbon) tests. In a comparison of field plot studies, control (unfertilized) plots gathered over 4 years were tested and the Solvita CO2-Burst correlated very closely with the yield, indicating a relationship of approximately 1:1 (mg kg CO2-C : mg kg N-mineralization). The data indicate that the Solvita soil CO₂ analysis kit could be combined with basic soil tests for soluble fractions of nutrients to aid commercial growers better appreciate soil carbon management and optimize N-fertilizer rates for environmental yields.

On the basis of our experiments, selenium is one of the most mobile element in a plant-soil system. Selenium is an essential microelement, a vital component of antioxidant system of organism. Deficiency of selenium is connected with emergence of many diseases among others the heart and vascular system one and the tumorous diseases. It’s contradiction derives from above given concentration dangerous to plants and human too. In the periodical system, selenium has the narrowest tolerance concentration range that is essential and toxic contents are close to one another.

Selenium content of plants influences mainly by the uptakeable selenium content of soil. In many countries soils are lack of selenium like in Hungary.

In our experiment with nutrient solution and in soil (in rhizoboxes) the effect of selenium supply was studied in a monocotyledon (maize) and a dicotyledon (sunflower) plants among controlled conditions.

In the experiments the dose was calculated and added as selenium in selenite form (concentrations: Ø, 1, 10, 100 mg kg^-1) and in selenate form (Ø; 0,1; 1; 10 mg kg^-1).
On the basis of our results the selenium content of plants was increased significantly by the effect of selenium treatments. This increase of selenium concentration was more intensive by the effect of selenate treatment than by the effect of selenite treatment applying the same level of treatment. The selenium concentration of shoot and root samples was analyzed respectively. Se content was higher in roots than in shoot samples in the case of maize and sunflower as well. This shows that the selenium accumulation in roots was more intensive than in shoots of the applied plants among the applied conditions.

The demand for potassium-containing fertilizers continues to grow globally to sustain food, fiber, and fuel production. While the role of potassium in plant nutrition is well known, soil potassium budgets are negative in many parts of the world, where more is removed in harvested crops than is returned back to the soil. The extraction process and production of key potash fertilizers varies depending on the geologic conditions. The major processes for mining and processing will be described. Although potassium is a finite natural resource, abundant geologic reserves are known to exist in many parts of the world and a plentiful supply is anticipated. The global trade and distribution of potash fertilizer is an important contributor to food security and sustainability and will be explained.

The aim of this study was to examine the influence of some organic and inorganic soil amendments on sorption and availability of phosphorus (P) to canola grown in an Alfisol amended with sewage sludge (SS) in the past. For this purpose a green house pot experiment was conducted in an acidic Greek Alfisol in which ten years ago SS at a high dose (300 t/h) was applied. The experimental design was complete block randomised including six treatments [soil treated with zeolite (Z), coal fly ash (FA), sugar beet factory lime (SBFL), and compost from olive oil processing wastes (COW), soil alone and the original soil without SS] each replicated three times. The mixtures (5 kg soil plus 50 g amendments) were cultivated with canola.

Soil and plant samples were selected after two month planting period and analyzed for available P. In addition, P sorption isotherms were prepared on soil samples after cultivation. The Freundlich equation was used to describe sorption characteristics. Phosphorus distribution coefficient (Kd) values were also obtained by the same batch equilibrium experiments.

Results showed that, application of high dose SS to the acidic Alfisol ten years ago, increased soil pH from 5.19 to 6.92, canola biomass from 1.96 to 5.3 g /pot, Olsen–P from 25.5 to 57.7 mg/kg^-1 and plant tissues-P from 1162 to 2881 mgkg^-1. Application of FA, Z, SBFL, and OW increased soil pH from 6.92 to 8.05, 7.07, 7.72, and 7.19, canola biomass from 5.3 to 8.6, 7.5, 7.6, and 5.4 g /pot and Olsen-P from 57.7 to 110.5, 61.2, 80.5 and 64.5 mg kg^-1 respectively. Application of Z, SBFL, and OW increased plant tissues-P from 2881 to 3048, 3320 and 3523 mgkg-1 respectively, while FA application decreased it to 2696 mgkg^-1.

Phosphorus distribution coefficient (Kd) were higher in the original soil compared to the soil amended with SS (23.3 vs 12.9 Lkg^-1 respectively. Application of FA, Z, and SBFL increased P_Kd from 12.9 to 23.19, 13.83, 14.48 Lkg-1 respectively, while OW application decreased it to 12.82 Lkg^-1. Kd values decreased with the concentration increase of the added P in the test solution in the case of the original non amended soil and FA treatment, while Kd increased relatively as the concentration of the added P increased in the test solution in the SS amended soil and Z, SBFL, and OW treatments.

Key Words: Phosphorus, bioavailability, sorption, biosolids, soil amendments, Alfisols

Olive which its importance has gradually increased on human health and nutrition, is a cultivated perennial plant, having economical importance in the Mediterranean Countries, the widespread olive growing area, besides Asia, America and North Africa Countries and also its production is made as table olive and olive oil. Olive growing is increasing in Aegean Region and following by Marmara and Mediterranean Regions in our country. Especially due to the establishment of new olive groves recently, the importance of olive growing has been increased. Although olive trees are resistant unfavorable conditions in comparison to other fruit kinds, the problems like yield and quality losses have appeared because of nutrition deficiency.

For this aim, the amounts of microelement in the soils of fruitful olive groves and the nutritional status of microelements of olive trees were determined and the relationships between the results of soil analyses and the results of leaf analyses were evaluated in the provinces of Ýzmir, Manisa, Aydýn, Muðla, Balýkesir, Çanakkale and Bursa in West Anatolia Region between the years 1997-2009.

In the result of the obtained datas, secure correlative relationships between the amounts of microelement in the soils and the amounts of microelement in the leaves were obtained.

Inputs of crop residues in agricultural soils are the primary means of sustaining soil organic matter levels. A field study was set out in 1990 on a loamy sand soil to quantify conservation tillage effects on crop residue-C decay and on its subsequent stabilization. A field technique of pulse labeling was used to produce mature ¹⁴C-labeled, above- and below-ground residues for common agricultural crops grown in southern Ontario, corn (Zea mays L.), soybeans (Glycine max L.), winter wheat (Triticum aestivum L.), winter rye (Secale cereale L.) and tobacco (Nicotiana tobaccum L.). Soils were managed under conventional (CT) mouldboard plough-disc and no-tillage (NT), and the recovery of crop C inputs was measured as 14C remaining. The decay rates of the labile residue C were positively correlated to residue water soluble C and N contents and negatively correlated to residue C:N ratios. Decomposition of the labile residue C was faster under CT, indicating that incorporated residues were exposed to a more favourable environment for microbial activity compared with residues left on the soil surface. Kinetic analysis of the patterns of crop residue decay showed that under CT the labile component was larger and decayed faster compared with NT, whereas the resistant component was smaller and decayed more slowly. Thus NT promoted the formation of a larger resistant component. Residue decay models specific for each crop/tillage combination better described the decomposition process than a single overall model.

A laboratory experiment was set up to compare solubility and “availability” of three phosphate fertilizer sources over a period of sixteen days after application to soils with varying pH levels. Three soils, one acidic and two alkaline, one of which will be non-calcareous and one calcareous, of similar texture and organic matter, were selected. Three phosphate products, namely, an ammonium orthophosphate (e.g., 6-22-0 or 6-24-0), a polyphosphate (10-34-0), and an ammonium mono phosphate (11-52-0) were applied at 100 mg kg^-1 and were compared to each other plus an unfertilized control. All treatments were replicated four times. The results are discussed.

This new, fully-referenced book of 515 pages has 20 chapters, four appendices, and a comprehensive index. Seven of the 225 fully-documented methods are field-based, 15 describe calculated attributes such as effective cation exchange capacity, while the remainder involve laboratory procedures with an Australasian focus. The book significantly expands the contribution made to the soil measurement profession by the Australian Laboratory Handbook of Soil and Water Chemical Methods of Rayment and Higginson (1992). That Handbook, now out-of-print, assisted the processes of method standardisation and analytical quality assurance by government and commercial soil testing laboratories across Australasia. For example, the Rayment and Higginson Handbook defined the chemical methodology used in all inter-laboratory proficiency programs for soils organized by ASPAC.

Chapters in the new book cover soil sampling, sample preparation and moisture content; electrical conductivity and redox potential; soil pH; chloride; carbon; nitrogen; phosphorus; sulphur; gypsum; micronutrients; extractable iron, aluminium and silicon; saturation extracts; ion-exchange properties; lime requirements; total miscellaneous elements; miscellaneous extractable elements; alkaline earth carbonates and contemporary laboratory and field methods for acid sulfate soils.

The preamble information in each chapter plus the soil-chemical methodology described is comprehensive, systematic, up-to-date, and designed to inform and direct practicing soil chemists, laboratory managers, educators, consultants and end-users. There is guidance on sampling and analysis through to reporting of results and expected analytical precision. Optional analytical 'finishes' are provided, including flow-injection analysis, flame technologies, and alternatives to “wet” chemistry. Environmental P tests and quantitative procedures for acid sulfate soils are among the new methodological additions provided. In addition, the new book retains and expands the method-coding system introduced in the Rayment and Higginson Handbook.

The hard-cover book from CSIRO Publishing retails for A$140. To order, contact:

CSIRO Publishing
150 Oxford Street (PO Box 1139), Collingwood, Victoria, Australia 3066

Telephone: +61 3 9662 7666
Email: publishing.sales@csiro.au
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BACKGROUND INFORMATION on Book Launch at 6th ISSPA, Brisbane
(The following information was included in the Program and Abstracts Booklet for 6th ISSPA.)

 

The current study was carried out to define the relationship between some properties of sandy soils characterized by low values of CEC and their content of different potassium forms. So, surface soil samples (0 – 30cm) were taken and collected from twenty-five location of some sandy soils of Egypt. The investigated soil samples were analyzed for some physical (particle-size distribution and the content (%) of CaCO₃) and chemical properties (total soluble salts, soluble ions, CEC, soil pH and OM) also different potassium forms (soluble, exchangeable, available, fixed and total) were determined.

Soluble-K was ranged from 0.0037 to 0.072 meq/100 g soil and it showed a significant correlation with EC and CaCO₃. On the other hand, it appeared no correlation with pH, CEC, OM, clay and silt. Exchangeable-K content ranged from 0.065 to 0.341 meq/100 soil and also it was significantly correlated with clay, CEC, silt and OM, but not correlated with EC, pH and CaCO₃. Available-K content ranged from 0.094 to 0.389 meq/100 g soil and has a significant correlation with CEC, clay, silt, OM and CaCO₃, while, it was insignificant with pH and EC. Fixed-K content ranged from 1.881 and 7.835 meq/100 g soil and this was significantly correlated with CEC, clay, silt and OM. On the contrary, fixed-K showed no correlation with CaCO₃, pH and silt. Total-K content ranged between 1.95 and 8.18 meq/100 g soil and showed positive and significant relation with CEC, clay and silt, however, it was not significantly affected with either pH, CaCO₃, OM or EC.

Soil Test Crop Response (STCR) approach is the best approach of plant nutrient application for crops, where in contribution of nutrients from soil, manures and fertilizers, and also by fixing the yield target, nutrient requirement of the crop will be decided based on the soil test values. In this study, STCR fertilizer prescription equation developed during 2007-08 for transplanted paddy was evaluated in comparison with recommended practice of fertilizer nutrients application and also to verify the STCR targeted yield equation developed for transplanted paddy for its suitability to aerobic paddy (Var:MAS-946-1), a field experiment was conducted at ZARS, Mandya during rabi/summer 2009-10.

The results clearly indicated that the STCR targeted yield fertilizer prescription equation developed for transplanted paddy can be well adopted for aerobic paddy crop in zone -6 of Karnataka state, India. Paddy grain and straw yields were significantly high (6572 kgha^-1 and 21160 kgha^-1 respectively) in STCR target of 75 q ha^-1 where nutrients were added through integrated STCR approach (50% oragnics+ 50% inorganics). However, yield targets could be achieved only at lower target (50qha-1).

NPK uptake by aerobic paddy was highest in 75 qha-1 target either through purely inorganic fertilizers or through integrated STCR approach. However, higher uptake of NPK in STCR target of 75 qha^-1 through only inorganics didn’t influence in increasing the grain yield of paddy. NPK nutrient use efficiency was significantly higher in the treatment where nutrients were applied through integrated approach for a yield target of 75 qha^-1 , where as lowest NPK uptake and nutrient use efficiency was recorded in 50 qha^-1 yield target through purely inorganic fertilizer treatment. This clearly indicated that the application of fertilizer nutrients by adopting STCR targeted yield equation through integrated approach will helps in enhancing the efficiency of applied fertilizer nutrients thereby increasing the aerobic paddy yield.

Potassium is an essential plant nutrient required in large amounts for normal crop growth and yield, but is often lacking or unavailable in agricultural soils. The general K requirement for optimal plant growth is 2-5% of the dry weight. When K is limited, growth is retarded due to the central role that K plays in many physiological and biochemical functions. Potassium is not a constituent of any known plant components, but it is integrally involved in metabolism and plant water relations. It serves as an enzyme activator in numerous enzymatic reactions in processes such as photosynthesis, respiration, carbohydrate metabolism, translocation and protein synthesis. In plant water relations, K is integrally involved in numerous physiological processes including maintenance of osmotic potential and turgor pressure, water uptake, and stomatal opening and closing. These roles of K in metabolism and water relations are manifested in K-deficient plants as decreased cell turgor, decreased water and nutrient uptake, decreased plant size, leaf area, photosynthesis, and carbohydrate transport, resulting in general growth retardation and lowered yields and fruit quality.

The cotton crop requires about 13 kg K/100 kg lint or about 2 to 5 kg K ha^-1 day^-1. In cotton, K plays a particularly important role in fiber development, affecting both fiber length due to turgor, as well fiber length and micronaire due to affects on carbohydrate transport and secondary wall deposition. Insufficient K also leads to poor cuticle development in cotton. Potassium has been reported to reduce the incidence of pathogens such as Verticillium wilt although the physiological reasons for this are not clear. Typical K deficiency symptoms in cotton consist of yellowish-white mottling of the leaves and necrosis around leaf margins and between veins, and eventually a rust color. Many of these symptoms are related to the disturbance of tissue water balance. Recent widespread K deficiency has been related to modern varieties developing bigger yields over a shorter fruiting period coupled with inadequate root uptake. The integral role of K in plant metabolism means that perturbations in plant K nutrition will result in decreased growth, yield and fiber quality.

 

Advances in technology available for crop production have brought information management to the forefront in decision-making for production practices and inputs.  Collecting, managing, and interpreting the various datasets with this technology help to characterize and document within-field spatial variability of each field.  Precision farming is a management system that utilizes that knowledge to adjust practices and inputs to best fit that variability, allowing decisions to be made on a site-specific basis.  One of the most basic sources of variation within a field is the soil.  With today’s technology, digital databases of soil characteristics tied to soil survey information can form the foundation for a record-keeping and management decision system. The farmer and his advisers can use these data to make decisions on fertilizer applications, tillage systems, crop genetics, and other inputs.  Soil testing and plant analysis enter the picture as a means of further characterizing the soil variability.  Soil testing integrates the natural soil chemistry and the effects of previous management---fertilizer additions and crop removal---giving layers of information on the variability in nutrient availability from the soil.  Plant analysis adds another layer of information providing details of actual uptake and removal of nutrients.  Soil and plant analysis thus becomes a critical resource for farmers who want utilize precision farming technologies to make better-informed decisions, leading to more efficient use of land, labor, and capital resources, increase yields, and reduce the environmental footprint of the management system.  Those who provide these analytical services need to be aware of how the changes in technology on the farm are impacting the value of analytical data in making better-informed decisions for nutrient management.  It is creating new business opportunities for your services.

The loss of sediments and nutrients from agricultural land to surface waters continues to be an important source of nonpoint source pollution. The close relationship between loadings of suspended solids and total phosphorus has been reported in many studies, particularly in areas dominated by cultivated land. In this study, long term (October 2004-September 2007) monitoring of suspended sediments and P was used to investigate if suspended sediment concentrations can be used to predict P loads in the Corbeira stream (Galicia, NW Spain), which drains a catchment of 16 km² with 65% of its area dedicated to forestry and 26% to grassland. Water samples were collected at the catchment outlet both in baseflow and runoff events, being the suspended sediment and P concentrations determined immediately afterwards. The relationship between SS and P is strong (r²=0.91), suggesting that P concentrations can be easily predicted if SS concentrations are recorded, which would, undoubtedly, make it possible to obtain P data quickly and reduce costs in terms of analysis. This strong positive relationship is likely to exist due to the fact that most of P exported in this catchment is PP (72% of TP), unlike most of the catchments with a high percentage of grassland. At event scale, although there is a significant positive relation, large differences in regression slopes have been noticed. Several factors could account for this, including the suspended sediment source as well as the size of the transported particles.

Our research aim was to prepare a method that enable to the estimation of soil’s variation level fertility reflecting the effective productivity in different area scale, based on soil and crop production databases. We analyzed the possibility of the emending of the fertility estimation accuracy on the National Pedological and Crop Production Database (NPCPD; in Hungary AIIR). The NPCPD database is possession of limited data queue to that chernozem soil’s variations, which are soil specific and can be characterized by specific soil properties. For this reason, the fertility data collected from the NPCPD database from 1985 to 1989 cannot be consider statistically reliable in case of certain soil varieties, and the applicability during the land qualification is questionable.

The plant production providing ability of the soil is expressible with different land quality indices. In Hungary, these indices come to in the late 1970’a years, and are based on field and laboratory measurements. The analysis of the important soil properties (soil variety, humus-, salt-, lime content, pH etc.) comes within these measurements, to which soil samples were collected from average 10-12 hectares areas from the plant cultivation lands. The Hungarian large-scale soil mapping [1:10000] is on ground of the results of the soil samples’ analysis and the derivative data of the field soil survey.

We elaborated an iteration method based on the derivative soil mapping information from the measured soil parameters, and on the soil and crop production databases, to make more precise the soil variation fertility estimation processes. We used this method on southern Hungarian plough-land areas. Our method is enabling to make more precise the soil-variation fertility data of the national-scale agricultural databases on the sample-area level with site- and plant specific. During the iteration we corrected the soil variety-average yields from the NPCPD with the multiannual parcel-level crop-yield data measured in the sample area. We analyzed the success of the estimation efficiency through the regression relations, and through the difference between the measured crop-yield and estimated fertility.

Organic acids has been developed for assessing the phytoavailability of micronutrients in soils, using highly concentrated solution and long shaking time. The objective of this study was to evaluate the performance of the organic acids extractant in three lower concentrations (100%, 50% and 25%) and four shaking time (30, 90, 180 and 360 minutes), comparing with the Mehlich-3 and DTPA extractant. The ability of organic acids (100%, 50% and 25%), DTPA and Melihch-3 for evaluating Cu, Fe, Mn and Zn were significant (p > 0,05) when correlated with the amounts of these elements extracted by wheat. Reducing th e organic acids concentration to 25% and the shaking time to 30 minutes, the extractant was as effective as the original one, suggesting that the organic acids extractant can be used diluted to 25% and 30 minutes shaking, favoring economy of reagents and analytical time in predicting the phytoavailability of soil Cu, Fe, Mn and Zn.

Trace element availability in acidic soils is high due to elevated H⁺ activity in the soil solution, which leads to competition with cationic elements for the colloidal adsorption sites. As a result acidic soils contaminated with trace elements need to be remediated, either by addition of soil amendments with high cation exchange capacity (such as zeolite) so that metal retention may be increased, or by liming the soil. In this experiment we aimed at studying the role of zeolite and liming in reducing trace element availability, as assessed by soil extractions and test crop (ryegrass, Lolium perenne L.) uptake. For this reason in an acidic soil (with pH 3.8) we added lime to improve pH to the value of 6.5. We then added to both treatments 15.5 mg Zn kg^-1 and 6.2 mg Cu kg^-1 and we amended soils with zeolite at three rates (equivalent to 0, 2 and 5 t ha^-1). Each treatment was replicated three times and was sown with ryegrass in one-kg soil pots. This resulted in 36 pots (2 pH values x 2 trace element levels x 3 zeolite rates x 3 replicates), which were placed in a greenhouse for 100 days. We found that soil extractability of Zn (with DTPA) decreased significantly with lime and was further reduced with zeolite amendment. The same was observed with Zn concentrations in plant (above-ground plant biomass was measured). However, Zn levels in all treatments were significantly higher than the unamended control. DTPA-extractable Cu, although it decreased in limed soils, did not exhibit any further reduction with zeolite additions. Copper and Zn availability was also found significantly reduced with liming and zeolite addition, when assessed with the estimation of metal transfer coefficients (g of metal in plant per kg of metal in soil

The upper middle São Francisco is the more arid region from the São Francisco Valley. The main economic activity is the irrigated agriculture, being focused on irrigated plantations of fruit. The irrigated areas are occupied by forty seven different crops with predominant grape and mango. The determination of pesticides in sediments can provide information to assess exposure and fate of these compounds in freshwater ecosystems. In this study were analyzed forty nine pesticides including various organochlorines, organophosphates, triazines and carbamates in sediments from the upper middle of São Francisco River (Bahia, Brazil) in order to evaluate their potential pollution risks. Samples of surface sediments were collected using a Petersen dredge at twenty one stations located between Sobradinho and Curaçá. The pesticides analyzed were: dichlorvos, chlormephos, ethoprophos, trifuralin, chorpropham, phorate, diazinon vinclozolin, chlorpyriphos, pirimiphos, malathion, fenitrothion, ethion, quinalphos, triadimenol, tetradifon, fenamiphos, chlorphevinphos, tebufenpyrad, procymidon, promethryn, p’-DDT, p,p’-DDD, p,p’-DDE, dicofol, methoxychlor, HCHs, aldrin, endrin, endrin aldehyde, endrin ketone, dieldrin, heptachlor, heptachlor epoxide, endosulfan (α, β and sulfate) and chlordane (α and γ). Extractions were carried out using the microwave-assisted extraction (MAE) method and multi residue pesticides determination was achieved by gas chromatography - mass spectrometry (GC/MS). The total pesticides concentrations ranged between 58.96 – 1,335.34 ng g-1, indicating low to high levels. The most frequent pesticides were endrin aldehyde, γ-HCH, β-HCH, α-HCH, heptachlor, heptachlor epoxide, chorpropham, chlorpyriphos, procymidon and triadimenol.

Keywords: sediments, multi residue pesticides, São Francisco River, Brazil.

Nitrogen  application increased the dry matter yields and the nitrogen uptáme by plants at early stages of vegetation (the 4th leaf). Nitrogen application significantly increased the yield of seeds, the diameter of inflorescence, the weight of thousand seeds, its oil content and oil production. The nitrogen application increased the oleic acid content (18:1) and it decreased the linoleic acid content (18:2) in the seeds.

Based on the results of project, which was applied in the frame of the Community Initiative program INTERREG IIIA and focused on environment protection (“Risk elements in the soil in relation to the environment”), critical loads for agricultural and forests soils are calculated. The critical loads calculation (mainly in forest soils) is the main task of the next project No 75 “Effects of acidification on the soil and water sources”, supported and co-financed by structural EU funds in frame initiative European community “Aim 3”.

Critical loads are determined as highest amount of contaminants, which don´t make chemical changes on the ecosystems, yet.  It is quantitative estimate of an exposure to one or more pollutants which significant harmful effects on specified sensitive elements of the environment do not occur according to present knowledge.

The results of the project are being compiled into well-arranged database giving freely accessible information about basic soil properties as well as risk elements in the soil. These results are important for next work – critical loads calculation. For critical loads calculation in relation to the others characteristics main and most important parameter is soil reaction (pH value), i.e. concentration of hydrogen ions in forests soils.

It was found that using categorical type soil structure data the estimation efficiency of the soil bulk density improved. The results may serve additional information to predict soil hydrophysical data more accurately.

Some of the selected basic parameters of soil fertility are observed in the Czech Republic in long term system of agrochemical soil testing, due to the use of fertilisers. More than 500 thousand hectares agricultural soil are tested every year and take away almost 80 thousand soil samples. The results of determination of soil reaction and contents of available essential nutrients (P, K, Mg, Ca) are stored in Land Parcel Information System (LPIS) - system based on the actual use of land in a geographic information database. Ministry of Agriculture of the Czech Republic uses LPIS as an administrative tool in control system and LPIS also functions as a service for the farmers themselves. A basic goal of LPIS is to allow farmers to obtain high-quality and comprehensible information about the blocks they use including current status of basic soil properties (pH value and available nutrients content) and fertiliser recommendations based on results periodic soil testing.

We studied the 0.01 M CaCl₂ extractable N fractions (NO₃-N, NH₄-N, N_org and N_total), N balances and yields in two long-term NPK fertilization experiments located in the Great Hungarian Plain. Our aims were to investigate whether the effects of long-term fertilization and irrigation are reflected in the 0.01 M CaCl₂ extractable nutrient content of the soil profile and to study the importance of nitrate leaching on Chernozem soils (USDA soil taxonomy: Molllisols) under different nitrogen- and water supply conditions.

On Haplic Phaeozem soil all nitrogen rates caused significant increase in CaCl₂-extractable NO₃-N and N_total fractions. These fractions were in significant and close correlation (r = 0.87; r = 0.88) with nitrogen balances as well, which means that 0.01 M CaCl₂ method is able to assess both N deficit and N surplus. On Calcic Chernozem soil, the 240 kg ha^-1 nitrogen rate increased NO3-N and Ntotal fractions significantly. This result is in accordance with yield data that proved that 240 kg ha^-1 nitrogen rate was not utilized. In this experiment, nitrate leaching was also investigated. Our study confirmed that as an effect of high rate nitrogen fertilization year by year deeper layers are affected by leaching. On irrigated plots nitrate leaching was more intensive.

Our results confirmed that N_org fraction has a high importance on the studied soils (14-44 percent of N_total fraction). Significant positive correlation (r=0.53) was observable between N_org content and the previous yield. It can be concluded that the N_org fraction depends on yearly mineralizable root and stubble residues, so it characterizes easily mineralizable N reserves.

The use of the organic-mineral fertilizer produced by the manufacturing industry of lysine and threonine amino acids in tropical soils can improve their fertility. The objective of the present study was to evaluate the influence of different dosages of the product named Ajifer L-14 on the increased production of a forage crop in a Red Latosol in the northwestern region of São Paulo State, Brazil. A randomized block design was used with seven treatments and four replications. The treatments were: T1- control (without application of Ajifer L-14); T2- control with natural vegetation; T3- mineral fertilization according to the cultivation need and soil analysis (using 1.35kg urea, 2.20kg single superphosphate and 0.51kg potassium chloride per plot, which corresponds to 60kg N, 40kg P2O5, 30kg K2O per ha-1); T4- fertilization with Ajifer L-14 according to the recommendation resulting from the chemical soil analysis (40 liters per plot-1, which corresponds to 60kg N ha-1); T5- fertilization with Ajifer L-14, with dose 50% above the recommended (60 liters per plot-1, which corresponds to 90kg N ha-1); T6- fertilization with Ajifer L-14 with a dose 50% below the recommended (20 liters per plot-1, which corresponds to 30kg N ha-1); T7- fertilization with Ajifer L-14 with dose 25% above the recommended (50 liters per plot-1 which corresponds to 75kg N ha-1); T8- fertilization with Ajifer L-14 with dose 25% below the recommended (30 liters per plot-1,
which corresponds to 45kg N ha-1). In regression analysis there was a polynomial relationship between the application rates of organic-mineral fertilizer and the production of dry matter and crude protein of Bracharia Brizantha.

Index Terms: fertilization, pasture, Ajifer

Iron (Fe) deficiency is a common nutritional disorder affecting vegetal crops grown in calcareous soils. The lack of this micronutrient is commonly corrected by the application of chelates. Moreover, Si fertilization has been described as an improvement in the tolerance to biotic and abiotic stress. Although, the role of Si on plant tolerance to stress has scarcely been investigated. Hence, the main objective of this work is to analyze the Si effect on the tolerance to iron chlorosis, the major symptom of iron deficiency.
Soybean plants (Glycine max L.) grown in hydroponic culture under iron partial deficiency (5µM Fe-EDTA) were treated with three Si doses (0 Si, 0,1mM Si and 1.0 mM Si). Samples of leaves, shoots and roots of the plants were collected at 10, 15 and 25 days after the treatments implementation. Si mobile forms were determined spectrophotometrically by the blue silico-molybdate procedure from fresh plant material. Samples digested with nitric acid were evaluated for their mineral content. Total Si content was calculated by ICP-MS and the rest of micronutrients (Fe, Zn, Cu and Mn) were analyzed by atomic absorption.

Soluble silicon content showed significant differences in plants submitted to high Si concentration after small periods of time. Significant differences in total Si content were observed in plants submitted to the three treatments. The highest values were reached in plants grown with 1mM Si. However, iron concentration decreased in these plants, suggesting the precipitation of Fe in presence of Si. That would explain the severe chlorosis symptoms observed. Thus, the tolerance to iron chlorosis in soybean seems to be not affected by Si addition under our work conditions. Therefore, new experiments have been carried out by our group in order to clarify if the Si has a positive effect in the iron deficiency tolerance.

Soil tests commonly used to develop K fertilizer recommendations, such as extraction by 1 M NH₄OAc at pH 7, measure both soluble and exchangeable K. Such methods are inadequate for soils that have a significant amount of fixed (non-exchangeable) K, a portion of which may be available to plants. The sodium tetraphenyl boron (TPB) method has been shown in some studies to provide a better measure of plant-available, non-exchangeable K. Cox et al. (1999) have published a simplified version of this procedure. A 5-min incubation with TPB allows the BPh₄ ion to combine with K+ in solution, causing precipitation of KBPh₄. This procedure extracts 1.5 to 6 times more K than NH₄OAc extraction. We are investigating the use of this test for predicting availability of fertilizer K applied to strongly K-fixing soils in California. These soils, formed in granitic alluvium from the Sierra Nevada, are found on the east side of the San Joaquin Valley. They contain vermiculite in the fine sand and silt size fractions. We have found extensive areas of such soils in cotton fields and wine grape vineyards. Four soil profiles, representing a range of K-fixation potential (Kfix), were chosen for this study. Kfix was measured by the procedure of Murashkina et al., in which 3 g soil is saturated (10:1) with 2 mM K and shaken for 1 hr. To evaluate K fertilizer requirement, KCl in solution was added in amounts equal to the Kfix of each sample. Samples were incubated moist for 1 to 7 days; then half were air-dried and half were maintained in the moist condition. K availability was estimated by both the NH₄OAc and TPB methods. The results of this work will be useful for determining K fertilizer application requirements for K-fixing soils.

 During our examinations, we established that the productivity and the starch content of the involved maize hybrids are significantly different as a function of their genetic potential, but starch content is independent of productivity. Based on the obtained results, our hypothesis is that starch yield primarily depends on productivity that is only slightly affected by the potential starch content based on genetic endowments. As a result of nitrogen fertilisation, the correlation between starch yield and grain yield became slightly weaker with increasing doses due to the fact that the starch content decreased with higher nitrogen doses.

The experiment was conducted in 2 polyethylene greenhouses located in Almeria (Spain) with ‘Mantra’ green bean crop (Phaseolus vulgaris ssp. volubilis), on a sand-mulched loam soil with trickle irrigation. The experimental design was a two-factorial with four replication per treatment. The treatments consisted of two Organic Matter levels (0.58% and 1.65%) and two System Crops (Organic and Integral). Fertigation levels were: 6.8 gm^-2 N, 1.4 gm^-2 P and 10.7 gm^-2 K following Regulation (CEE) Nº 2092/91 (Organic Crop System) and Specific Regulation of Green Beans Integrated Crop Production (BOJA) Nº 10/01. Treatments established were: E₁: Organic Crop System (OCS) under Low Organic Matter Soil (LOMS). I₁: Integrated Crop System (ICS) under LOMS. E₂: OCS under High Organic Matter Soil (HOMS). I2: ICS under HOMS.

Five samplings were made during the harvest from 56, 63, 73, 79 to 84 Days Afters Sowing (DAS). Each sampling includes 8 samples per treatment. Green bean fruit production was evaluated through the crop by the following parameters: Marketable production (category I and II), total marketable production, unmarketable fruit and total production. Quality was evaluated by the following parameters: Dry matter content of fruit (g) (DMC), total soluble solids (ºBrix) (TSS), pH and tritable acidity (mmolc citric acid L^-1 of juice). E₁ shows lower total marketable production, unmarketable fruit and total production, than other treatments. E₂, I1 and I₂ show similar production parameters. Nevertheless, the distribution between categories was similar for all treatments. Dry matter content of fruit (DMC) has been similar in all treatments.

Along harvest period, average total soluble solids were similar for each treatment, with values around 5.3. ICS shows significant higher values in the second, fourth and fifth sampling. Average pH value, along harvest period was similar, with values around 5.9. Nevertheless, acidity increased during the harvest period. Non remarkable pH tendencies were found between treatments. Acidity does not show significant differences between treatments, except in the fifth sampling, where OCS were higher than ICS treatments.

Key words: Fertigation, marketable fruit, dry matter content of fruit, total soluble solids, pH and tritable acidity.
 

Plant nutritional diagnosis requires specific reference levels for each variety which faithfully reflect the nutritional status of the crop. A vine nutritional survey was undertaken in the Rioja appellation in north-eastern Spain. The survey method was used to establish preliminary Reference Levels to be applied to the nutritional diagnosis of blade and petiole tissues of Vitis vinifera L., cv. Tempranillo tinto on Richter-110 rootstock. These References were generated from data obtained throughout twelve years (2000-11) from 166 vineyards. The obtained database includes data from different altitudes, soil types, cultural practices, and climatic conditions within the Rioja appellation. The training systems were Goblet, Guyot, and Double Cordon Royat espalier pruning. In general, vineyards had a dry farming irrigation regime and a homogeneous mechanical tilling. Nitrogen, P, K, Ca, Mg, Fe, Mn, Zn, Cu, and B were analyzed in blade and petiole dry tissues sampled at flowering and veraison.

Data were statistically analyzed to obtain the Normal average values considering the (μ ± 0,25σ) of the central data as optimal levels and the tails values (μ ± 0,84σ) of the population as excessive or deficient levels. Vineyards with phytosanitary damages or troubles at flowering, and data with extreme nutrient values were ruled out. The statistical procedure included the Kolmogorov-Smirnov non-parametric test for normality, mathematic transformations for normality and the calculation of percentiles when those transformations to Normal distributions become unlikely (P20, P40, P60, and P80). Finally, Reference Levels for blade and petiole at flowering and veraison are proposed for Tempranillo tinto grapevine in the Rioja appellation.

For economical wheat production very important role is effective nitrogen fertilizer application. Insufficient or excessive nitrogen levels reduce profit and yield. Split topdressing of nitrogen fertilizer improves nitrogen efficiency. Plant leaves tests and chlorophyll meters can be used to help make the decision. The aim of experiments was to determine releationship between nitrogen and chlorophyll content in four winter wheat (Triticum aestivum L.) leaves duration of vegetative period. The experiment was carried out on brown lessive medium loam soil, in Latvia for two years. The plant material for nitrogen analyses and chlorophyll a/b ratio determine were collected at the Zadoks Growth Stage (ZGS) 32 (beginning of shooting into stalk), at the ZGS 51 (beginning of shooting into ears), at the ZGS 69 (end of flowering). The results of the experiment on nitrogen content in the plant leaves testify that nitrogen dynamic changes depend not only on the duration of the vegetation period, but also on the background of nitrogen fertilisers. Diverse winter wheat varieties under different fertilizer treatments essentially affected leaf N concentration. There were observed that nitrogen content closely correlates with chlorophyll content in leaves. Correlation depends from meteorological conditions and variety.

Plants of the genus Allium gain their characteristic taste and odor from a group of volatile compounds containing several sulfur atoms. The key enzymatic reaction preceding the generation of the smells is the production of a chemically reactive sulfenic acid which then spontaneously reacts to form all these interesting substances. Alliinase is the enzyme involved, with full name S-alk(en)yl-L-cysteine sulfoxide lyase. So far, the nucleotide sequences of the alliinase genes from most of the Allium species are known, with two exceptions: Allium obliquum (twisted-leaf garlic) and  Allium sensescen ssp. montanum (German garlic). Here we present a comprehensive investigation of the genes encoding alliinase in four Allium species, including the two mentioned above. Furthermore, a phylogenetic study of the four species was accomplished, based on the nucleotide sequences of the 18S rRNA genes.

The study material used here was represented by plants belonging to four Allium species, sampled from various locations in Transylvania, Romania. Total RNA isolated from leaves and bulbs was used for cDNA synthesis, with specific commercial kits. Alliinase-specific primers were designed using information from the GenBank database. With these primers, fragments of the alliinase genes were amplified by PCR, and further sequenced. The 18S rRNA genes were also amplified and sequenced using specific primers. Next, the alliinase fragments were multiple aligned with other related fragments from GenBank, in order to identify similarities/differences between them. Furthermore, the 18S rRNA fragments were used in a phylogenetic study, with specific bioinformatics tools.

The comparison involving the alliinase genes from Allium obliquum, Allium senescens ssp. montanum and other related nucleotide sequences from public databases allowed us to identify both similarities and certain differences between these fragments. Several differences in the amino acid sequence of these enzymes are emphasized, suggesting some particularities when compared with other molecules of this family of enzymes.

This work was supported by CNCSIS –UEFISCSU, project number PNII – IDEI code 2272/2008.

The results showed that 54 % of pistachio orchards included in the study presented leaf nitrogen concentration below the critical value; the relevant percentage in the case of phosphorus was 20 % and that of potassium 22 %. Calcium level was found to be within the normal range in all orchards whereas leaf chlorine was in excess in some cases. With regard to micronutrients, iron, manganese and boron, levels were within the normal ranges, 30-50 ppm, 20-80 ppm and 100-200 ppm, respectively but zinc was found to be below the critical value in 51 % of the orchards tested. As for the symptoms observed, the first type of symptoms should be related to low K and/or excessive Cl^- concentrationwhereas the second one should be to Zn deficiency. The investigation of both the aforementioned nutritional disorders will be continued in the following growth period in the area by studying several plant, soil and irrigation water parameters.

In order to study the effects of Nitrogen fertilizer and Cattle manure application on growth characteristics of potato (plant height and shoot dry matter), a field experiment was conducted in April 2008 in Iran, with factorial arrangement based on randomized complete block (RCB) design with three replications. Treatments were consisted of N fertilizer in three levels (50, 100 and 150 Kg h^-1) and Cattle manure in four levels (5, 10, 15 and 20 ton h^-1). From the 45^th until the 105^th day after emergence (DAE), plant height and shoot dry matter were measured every 15 days. Results showed that, in all times, plant height and shoot dry matter were increased significantly by increasing N fertilizer. Also, in all times shoot dry matter showed significant differences in relation to manure. Results nearly showed that, shoot dry matter was increased by increasing manure. In the same way, plant heights were risen significantly by increasing manure at the 45^th, 60^th, 75t^h, 90^th DAE. Furthermore, the interaction between manure and N fertilizer on shoot dry maters were significant at 90^th and 105^th DAE. Maximum shoot dry matter at the 90th DAE (87.118 g) was obtained by using manure at 20 Ton ha^-1 + N fertilizer at 150 kg ha^-1, while, at the 105^th DAE, it (106.998 g) was obtained by using manure at 15 Ton ha^-1 + N fertilizer at 150 kg ha^-1. Also, the interaction between manure and N fertilizer on plant heights were significant at 60^th, 75^th, 90^th and 105^th DAE. Maximum plant heights at the 60^th and 90^th DAE were obtained by using manure at 20 Ton ha^-1 + N fertilizer at 150 kg ha¹, whereas, at 75^th and 105^th DAE the maximum plant heights were obtained by using manure at 15 Ton ha^-1 + N fertilizer at 150 kg ha^-1.

The Transylvanian Plain (TP), Romania is an important region for agronomic productivity. However, limited soils data and non-use of best management practices hinder land productivity. Transylvanian Plain, with an area of approx. 395,000 ha, has a predominantly agricultural character, and in the past, because of the large areas of agricultural land, with fertile soil, produced large quantities of grain, for economic and social needs of the country. Cereal and steppe character (or anthropogenic steppe) of the area, led to widespread of the popular term "plain", as over 30 villages, located in mid-southern region, wears, along with their name, the addition "plain". In time, however, because of rugged terrain, deforestation, fixation of the public lakes on quick slopes and irrational agrotehnics for the crops, large areas of productive agricultural land were turned into degraded land, with reduced productivity or unproductive. After Ministry of Agriculture and Rural Development of Romania data, about 1954 hectares of the Transylvanian Plain area, are aside agricultural production and tens of thousands of hectares are with productivity greatly reduced under the normal. Another feature of the TP is that, although it is lower than the surrounding region, no major river valleys, no major roads, do not converge to its center, but it surrounds it on the periphery. So it is a poor area in water resources, avoid by the heavy traffic, and so it partly explains its rural character and layout of cities around the edges.

The last research upon the evolution of the climate inside the Carpathian basin, pointed out an increase of the air temperature in the last one hundred years with about 0.7 C. This fact is also shown by the fact that, six of the warmest years of the 20th century were registered in 1990’s. Contrary to its name, the TP is not a geographically flat plain, but rather a collection of rolling hills approximately 300 to 450 m above sea level in the south and 550 to 600 m above sea level in the north. Climate of the TP is highly dynamic, ranging from hot summers with high temperatures of >25 C to very cold winters with lows -5 C. The southern TP generally has a xeric moisture regime with steppe vegetation while moisture increases somewhat in the northern TP as an udic moisture regime. Twenty datalogging stations have been deployed across the TP on divergent soil types, slopes, and aspects. The location of each site was recorded using Garmin eTrex Vista (Olathe, KS, USA) handheld GPS units. Ten datalogging stations were installed in March of 2008, with an additional ten stations installed in March of 2009. HOBO Smart Temp (S-TMB-M002) temperature sensors and EC-5 (S-SMC-M005) moisture sensors were connected to HOBO Micro Stations (H21-002) at each site (On-set Computer Corp., Bourne, MA, USA). Additionally, at 10 of the 20 sites, tipping bucket rain gauges (RG3-M) were deployed (On-set Computer Corp., Bourne, MA, USA).

At sites with a tipping bucket rain gauge, the following data were recorded: soil temperature at 10, 30, and 50 cm; soil moisture at 10 cm; surface air temperature; and precipitation. At sites without a tipping bucket rain gauge, the following data were recorded: soil temperature at 10 and 50 cm; soil moisture at 10 cm; and surface air temperature. Data is downloaded from the Micro Stations every two months via laptop computer using HOBOware Pro Software Version 2.3.0 (On-set Computer Corp., Bourne, MA, USA).

Calculation of soil temperature regime according to the Soil Survey Staff (2006) consists of averaging soil temperatures at 50 cm between summer (June, July, and August) and winter (December, January, and February). The Soil Survey Staff (2006) defines mesic soil temperature as a “mean annual soil temperature that is >8 C, but <15 C where the difference between mean summer and mean winter soil temperatures is more than 6 C at 50 cm or at a densic, lithic, or paralithic contact, whichever is shallower.” Year 2 data from sites 1-10 show that all sites have a mean annual soil temperature of 10 C at 50 cm with more than 6 C variation between summer and winter. Thus, it appears as though mesic is the appropriate soil temperature regime for soils of the TP.

However, differences in seasonal warming and cooling trends across the plain were noted. These have important implications for planting recommendations.

Vertisols have the tendency to restore damage of their structural units through sequential wetting/drying cycles. The aim of this study was to evaluate the influence of microbial activity and plant growth on aggregate formation in a Vertisol. Surface soil was collected, air-dried and pushed through a 1mm sieve, to break up all macro-aggregates >1mm.The homogenized soil was exposed to five wetting/drying cycles under two water regimes as follows i) continuously wet (c/w): the soil was watered to field capacity and allowed to dry until the 50% of field capacity was reached, and ii) wet-dry (d/w): the soil was watered to field capacity and left to air-dry. In sub-samples of the c/w water regime, plants of Lycopersicon esculentum were grown. During the first wetting/drying cycle two biocides, a fungicide (natamycin) and a bactericide (cloramphenicol), were mixed to the drenching water to suppress microbial populations. For each of the former treatments, there were samples that served as controls. After the end of each wetting/drying cycle, the aggregate size distribution (ASD) and the bulk density of the different size classes of aggregates (ABD) were determined.

Water regime influenced aggregate formation and bulk density. D/w cycles enhanced the formation of smaller and denser macro-aggregates, compared to c/w. The microbial activity had little impact on ASD. Plant growth influenced strongly the dynamics of small macro-aggregates. ABD increased as aggregate size decreased. Biocides application reduced ABD, compared to the control. Only in the presence of plant, inhibition of microbial activity resulted in the formation of denser aggregates.

As a part of our research project according to nitrogen flow in soils and vegetable cultures, were made our experiments in the nursery garden of our Institute (Kecskemét College, Faculty of Horticulture), using large volume lysimeters. At constant phosphorus and potassium fertilizer doses (P₆₀:K₁₂₀), four different nitrogen doses (0, 60, 120 and 180 kg ha^-1 N) were used.  Three different soil types (sandy, alluvial and chernozem soils) were studied. Total N levels and other parameters were determined in two harvesting times according to tomato (type K-549) and sweet corn (type Spirit) as well.

Laboratory tests were made in the Soil and Plant Testing Laboratory of our institute. Total nitrogen levels were determined by Kjeldahl method (FOSS Kjeltec 2300), total phosphorus and potassium contents were analyzed by an ICP spectrometer (HORIBA Jobin Yvon) after microwave digestion. Leaf analysis clearly confirmed N translocation from the old leaves to the young ones. Translocation of potassium in leaves was also shown, whereas phosphorus content did not differ in young and old leaves considerably. These observations emphasize the importance of sampling in the planning of these examinations. Potassium levels in tomato fruit decreased continuously by increasing N doses. Plant examinations in sweet corn confirmed the translocation of nitrogen during growing and ripening, and the effects of N doses were shown as well.

According to the chemical composition of the tested vegetables, organic acid contents increased in tomato berry on sandy and alluvial soils at higher nitrogen fertilizer doses. Sugar content was higher in tomato grown on alluvial and chernozem soils. Nitrogen doses decreased sugar contents in chernozem in the case of both vegetables. The increase in vitamin C levels of tomato in sandy soil was slight due to higher nitrogen doses.

A fertilizer factorial experiment of randomized complete block design was conducted in pots under greenhouse conditions using lettuce (Lactuca sativa L.) as test plant. Plants of lettuce were grown in a calcareous sandy clay loam soil with different N and B fertilizer levels, in order to investigate the effect of applied nitrogen and boron as well as their interactions on nutrient distribution in leaves and roots of lettuce plants. Treatments consisted of four levels of N (0, 200, 400, and 600 mg N kg^-1 soil) and two levels of B (0 and 5 mg B kg^-1 soil). The results showed that increasing N level up to 600 mg N kg^-1 significantly increased soil ΝΟ₃- - N and K but had no effect on soil available P and B. Application of 5 mg B kg^-1 soil significantly decreased available K while P concentrations increased. Nitrogen application increased leaf and root N and reduced leaf P and K. By increasing N concentration in the soil, leaf B concentration was reduced in all N treatments. However, B had no effect on the N, P, and K content of leaves.In the case of roots, B was affected by N treatments and it was reduced significantly in the treatment of 600 mg N kg^-1 soil + 5 mg B kg^-1 soil.
These results suggest that nitrogen fertilization has a potential effect to prevent B toxicity and to keep leaf B concentration at normal levels in lettuce plants. Therefore, the appropriate management of N fertilizers in soils with excess B is very important.

Keywords: boron content, nutrients, nitrogen fertilizer levels, calcareous soil, lettuce
 

Based on the most recent climate change predictions referring to the Carpathian basin, the probability of the occurrence of drought periods will increase in the future. Therefore, the examination of irrigation strategies adjusted to local environmental conditions is especially important today. The aim of our examinations was to develop a computerized irrigation decision support system (CIDSS) capable of modeling the water balance of maize and soil and climatic drought simulation that is frequent in Hungary. The modeling of temporary water deficit was performed by further developing the idea of Doorenbos et al. (1978). A new drought tolerance algorithm was applied to describe the plant adaptation in climatic drought. The essence of this method is the determination of critical soil water content, under the plant starts closing his stomata, taking soil water characteristics into consideration. This value is not permanent, depends on potential evapotranspiration (PET) and drought tolerance of plant. The results of the CIDSS can be accessed via the web. The most important information for users are provided by the daily values (water balance, PET, actual evaporation, transpiration of the soil and vegetation, LAI, critical water content, water deficit, etc.) calculated and modeled by the irrigation recommendation. Knowing these, one can decide about the necessity of irrigation, its starting date and the extent of irrigation. Even questions starting like "What would have happened if…" can be answered with this system. One can carry out analyses that are interesting from the aspect of practical production, whereas scientific propositions (e.g. climate change, sowing date, effect of edaphic factors on the water balance of the given crop, etc.) can also be examined.

Pollution by arsenic is a potencially serious problem throughout the world. Arsenic may occurs from geological (As-bearing minerals) and anthropogenic sources (coal combustion, irrigation with arsenic containig water, arsenic based herbicides and insecticides). Inorganic arsenic species are the mainly present forms, which can be found in surface and subsurface water bodies, many foods, and soils, except in marine boita where the organic compounds (e.g. arsenobetain) prevail. The mobility, uptake and toxicity of arsenic compounds vary with valance states (As(III), As(V)) and forms (inorganic, organic).

An experiment was built to evaluate the usability of stored soil samples originated from the long-term field experiment Nagyhörcsök (Hungary) for arsenic speciation investigation. It is know that inorganic species may alter during storage neither in water nor in soil samples. To establish the conversion rate soil samples was loaded with arsenite and arsenate apart. A pretreatment procedure was developed to extract the arsenic species to be able to determine the change in their concentration. Shaking methods and extractants were compared.

The results indicated that both forms suffered change during a year-long storage, moreover presumably oragnic compounds formed in the air-dried samples. Thus arsenic speciation investigations must be done straight after sampling.

Nitrogen (N) is one of the major plant nutrients and is extensively used in plant production, mainly as inorganic fertilizers. Fertilizer N is either taken up by the plant or lost by leaching, volatilization and immobilization. While soil nitrate and ammonium (mineral N) are readily available for plant uptake, residual N in the profile is important in fertilizer recommendations. Management of N is particularly crucial in irrigated areas. Part of the research in the Akarsu Irrigation District in southern Turkey in 2010 aimed to determine mineral N level in the effective rooting depth. Representative soil samples were collected from 107 points of the research area, and analyzed for nitrate and ammonium. Nitrate concentrations were the highest in the surface horizons (57.8 mg kg^-1) and decreased by the depth. However, ammonium concentrations were far much lower than the nitrate concentrations (2.1 mg kg^-1) throughout the profile. Nitrate concentration in the surface varied regardless of the soil type, but influenced by the fertilizer practices. Therefore, systematic monitoring and determination of mineral N analysis within any irrigation system is imperative from the economical and environmental standpoints.
 

In the present paper, the reclamation of Pb-contaminated soils by adding zeolite, bentonite, goethite and two newly produced adsorbents consisting of zeolite and goethite (systems I and II) was studied. The above adsorptive materials were used to reduce the transfer of Pb to plants which were cultivated to these soils. For this purpose, a greenhouse pot experiment was conducted in four replicates as follows: 5 g of zeolite or bentonite and 1 g of goethite or zeolite – goethite (system I or II) were added in pots which contained 1 kg of soil. Then, 1 mg of Pb and plant seeds of wheat, maize and cotton were added. A number of 300 pots were produced including also the unamended control. Forty days after germination, the plants were collected, the morphological characteristics were identified and the available Pd in soil (extracted with DTPA) and the total Pd in plants were determined. Comparing the experimental results, the highest decrease of available Pb was presented to soils, which contained goethite and zeolite-goethite (system II) and in pots grown with wheat and maize, respectively. Moreover, the adsorption of Pb from plants was significantly reduced in all treated soils especially in the zeolite-goethite treatment (system I) in pots grown with maize, compared to the unamended control.

 

Keywords: Pb, zeolite, goethite, bentonite, zeolite-goethite systems        

 

 

Molybdenum as a constituent of several important enzymes is an essential microelement. It can be found in all kind of food naturally at low level. However, environmental pollution, from natural or anthropogenic sources, can lead to high level of the metal in plants.

Our study is based on the long-term field experiments of Nagyhörcsök (Hungary), where different levels of soil contamination conditions are simulated. Plant samples were collected from the experiment station to study the behaviour of elements: total concentration, available concentration, leaching, transformation, uptake by and transport within the plants, accumulation in different organs, phytotoxicity and effects on the quantity and quality of the crop.

In this work we present the effect of molybdenum treatment on the uptake of other elements. Molybdenum is proved to be in an antagonist relationship with copper and sulphur, while molybdenum-phosphorus is a synergist interaction. However, in most of the plants we studied increasing molybdenum-treatment enhanced cadmium-uptake. We have found the most significant cadmium-accumulation in the case of pea, spinach and red beet.

The most presumable reason for this phenomenon has been thought to be alteration of pH due to the treatment of soil by molybdenum, although results of pH determination haven’t confirmed it.
There can be another likely explanation that assumes formation of dimeric adducts in the plasma of ICP-MS spectrometer. This possible reason is also studied in present work.

Although sprout consumption in Hungary is not as widespread as it is in the Far-East, due to its outstandingly high nutritional value, it would be recommendable to consume sprouts.

In our experiments the seed of a monocotyledon (Triticum aestivum) and a dicotyledon (Pisum sativum) was chosen as the two types of plants highly differ in nutrient intake.

The experiments can be divided into two major groups:

1. treatment of sprouts with molybdenum and selenium

2. microbiological analysis of sprouts


1. During the treatment of sprouts with molybdenum and selenium (selenite, selenate), the water used for the germination and soaking of the seeds have been supplied with increasing molybdenum, selenite and selenate concentrations.

Element content of sprouts was analysed continuously during germination to examine changing of the concentrations.

2. During the microbiological analysis of the sprouts plate count, total coliform content, total yeast and mould content were determined before soaking of the seeds, after 12 hours of soaking, and on each day of germination.


As a result we can draw the conclusion that it is advisable to treat sprouts with molybdenum and selenium, since sprouts are able to intake these elements in high concentration and thus they can contribute to cover our daily molybdenum and selenium needs to a great extent. On the other hand, it has become apparent that microbiological load of the seeds is already high and it increases during germination. Therefore, decreasing microbiological infection of seeds is extremely important and initial microbiological load should also be controlled.

Soil pollution with copper (Cu) in Moldova is caused mostly by the horticulture plantations in the agricultural structure. The plantations are repeatedly treated with different pesticides along with Cu- and Zn-containing products during the whole agricultural year. Accumulation of Cu in the superficial soil strata leads to a dynamic disbalance in the soil-plant-atmosphere system, to multiple deviations in the nutritive system, aggravation of population’s health. The aim of the research was to study the influence of Cu surplus on the growth and mineral status in different plants that present an interest for monitoring soil conditions and development of efficient techniques and procedures of their improvement, prevention and avoidance of pollutant penetration in the human’s alimentary chain. The experimental work was conducted in the vegetative complex of the Institute of Genetics and Plant Physiology ASM. Trace element content has been determined in soil and in the plants of vine, clover, alfalfa, mixture of cereal grass crops, growing under Cu excess. It has been shown that Cu surplus in soil contributes to decrease in the content of the accessible forms of some elements in soil (Fe and Zn), to Cu excessive accumulation in the roots of annual plants and grape, which inhibits plant growth and some metabolic processes, retards the transport of trace elements to the above-ground organs of plants. Cu impedes Fe transport to above-ground organs, decreases Fe content in grape shoots and leaves. Such deviations contributes to appearance of visual chlorosis symptoms and decrease of vine resistance to low temperature in winter. Utilization of Cu-accumulating plants (alfalfa, cereal grass crops) after uprooting of perennial plantation may serve as one of the promising elements in the technology of Cu phytoextraction from soil.

Olive groves are characterized by rich flora and fauna and host a strong biological activity. Aim of the present study was based on diversity and the identification of specific herbaceous plants related to different management systems in olive grove ecosystems in two sites (Nies and Pteleos) of Magnesia Prefecture (Central Greece). Vegetation analysis was conducted in May 2007 by using 50x50cm sampling plot. The study examined: 1) five diversity indices, plant species richness (S), Margalef, Brilluin, McIntosh and Menhinick indexes, 2) the classification of the plant community diversity for specific types of management systems of olive groves (organic in Pteleos – organic in Nies – conventional non-sprayed in Pteleos – conventional non-sprayed in Nies – conventional sprayed in Pteleos – conventional sprayed in Nies) on the basis of the diagram of Renyi, 3) the similarity of the two management systems (organic and conventional) on the basis of plant species they host with Cluster Analysis and 4) species-system relationships using the Indicator Value Analysis (IndVal) in order to provide species-indices for specific types of management systems of olive groves. The results showed that the organic system in Pteleos favored the plant species richness (0.67), Margalef (6.06), Brilluin (2.92), McIntosh (0.83) and Menhinick indexes (2.62) more than the other types of management systems (p<0.05). Diagram of Renyi showed higher plant diversity in the organic system in Pteleos. According to Cluster Analysis the organic olive groves in Pteleos and the conventional non-sprayed ones in Pteleos showed a strong similarity as regards the plant diversity. The same was detected in the pairs: conventional non-sprayed in Nies– organic in Nies and conventional sprayed in Nies – conventional sprayed in Pteleos. IndVal analysis revealed two “characteristic” types of indices, Chenopodium album (81,2%) in the organic olive groves in Pteleos and Sinapis arvensis (76,6%) in the organic ones in Nies.

The choice of species that accelerate the soil chemical and physical balance is an alternative to accelerate the recovery degraded soil. The Brachiaria decumbens pasture is used in virtually all of Brazil, because it adapts to various soil types and endure low levels of some nutrients from the soil. The use of pasture in the recovery of degraded areas has been used to promote coverage of the soil and provide nutrients to the soil. The objective this work was study the production of dry matter of B. decumbens tilled an Oxisol in process of recovery for 11 years using green manures, limestone and gypsum. The experimental design was a completely randomized with nine treatments and four repetitions. The treatments were: one control (tilled soil without culture) until 1999 after the implanted the B. decumbens; Stizolobium aterrium until 1999 after the implanted the B. decumbens; Cajanus cajan until 1994 and then substituted by Canavalia ensiformis and since 1999 was implanted B. decumbens; lime+S. aterrimum until 1999 after the implanted the B. decumbens; lime+C. cajan until 1994 and then substituted by C. ensiformis and since 1999 was implanted B. decumbens; lime+gypsum+S. aterrimum until 1999 after the implanted the B. decumbens; lime+gypsum+C. cajan until 1994 and then substituted by C. ensiformis and since 1999 was implanted B. decumbens. Were evaluated the dry mass of B. decumbens and the growth rate of tree species. The results were analyzed effectuating the analysis of variance, Scott-Knott to 5% of probability to compare averages. The production of B. decumbens obtained similar results when comparing the treatments.The production of dry matter of B. decumbens was influenced by the variation of water availability and photoperiod.

Soil quality has a huge influence on plant quality. However, the factors affecting soil quality may be strongly influenced by different agronomic practices that are performed, as well as soil type and physiographic position. For this reason we have compared the influence of two types of agricultural practices (conventional and organic) and two soil types (on marls and colluvial limestones) on the physiological quality of the olive trees in a semiarid Mediterranean climate area from Barranco del Atanor (Sierra Mágina Natural Park, Southern Spain), where the study is located. Ethylene content and water content both in leaves have been measured.
The preliminary results for these parameters show that between the marly soils and colluvial soils were not statistically significant differences. However, for water content, we see that there was greater water capacity in plants from colluvial soils. For this plant parameter we found significant differences between organic and conventional management, with a greater water capacity in the latter. With respect to the ethylene content was not found significant differences between plants from colluvial soils and plants from marly soils, but there is a trend for olive plants in colluvial soils have less amount of ethylene. Similar results were obtained by comparing the amount of ethylene under conventional management and other organic; the amount of ethylene was lower in an organic management. The physiographic position factor also affected the amount of ethylene in leaves, because it was found that the highest positions had a lower content of ethylene that the middle areas, and increases in the lower positions. Overall, these data show that the plants are less stressed under organic management, and also this can be considered as environmentally sustainable management.

Soil field properties are easier and cheaper to obtain than analytical, but no Field Soil Quality Index (FSQI) has been proposed. Here, a FSQI has been made using a non-linear PCA with optimal scaling (NLPCA) and applied to evaluate olive groves in Jaén.
A soil data base was implemented with 169 soil profiles and 22 field variables (categorical) based in the next properties: color, structure, consistence, texture, porosity, roots, topography, terrain position, slope gradient and parent material. Each soil profile corresponds to one of the next Land Use Types: Little-disturbed forest (Quercus broteroi; LDF), Xeromorphic woodland (Quercus rotundifolia; XW); Semi-naturalized plantation forestry (Pinus sp.; FP), Xeromorphic Scrub (XS); Pastures and degraded grassland (PDG), Annual field cropping (AFC) and Olive groves (OL). Variables were further combined into a FSQI that would take into account their respective abilities to separate sites with different soil qualities.

First, the original data matrix was randomly divided in 2 sets: a 100x22 matrix (the training set) and a 69x22 matrix (the validation set). Second, NLPCA was applied to the training set, obtaining a set of optimal scores for the categories of the variables and the Variance Accounted For each variable (VAF). Third, the original categories in the validation set were substituted by its optimal scores. Finally, the FSQI were obtained as the sum of the optimal scores weighted by the VAF and reduced to a common range (between 0.1 and 1).

 

The mean FSQI value was significantly lower (p > 0.001) for OL (0.381) than for the next subgroups: 1) AFC and PDG (0.416 and 0.506, respectively); 2) XS, FP and XW (0.650, 0.724 and 0.754, respectively); and 3) LDF (0.941). Likewise, the FSQI introduced the ability to separate (p <0.001) the OL management systems in Jaén: Traditional farming (0.381) vs. Ecological farming (0.742).

The use of high amounts of fertilizers in the greenhouse crops in southeastern of Spain leads to important environmental problems due to the leaching of elements. The knowledge on plant nutritional requirements is necessary to attain and develop a technical efficiency. The experience was development in a polyethylene greenhouse ‘Aifos’ pepper crop, on a sand-mulched sandy loam soil and fertigation with regenerated water. The experimental design was randomized blocks with four blocks. The treatments were N0K0, N₁K₁, N₁K_1.5, N_1.5K₁ and N_1.5K_1.5, being N₁K₁ the recommended rate (125 kg ha^-2 of N and 193 kg ha^-2 of K and average nutrient concentrations of 9.8 mM N (NO₃-+ NH₄+) and 5.4 mM K). Eight plants per treatment were collected at five growth stage (0, 56, 84, 113 and 155 days after the seedling transplant, DAT). Dry matter and content of nutrients (N, P, K, Ca and Mg) were monitored for different plant parts (pinch rest, fruit, leaf, and stem). The increase of NK doses produced a significant greater extraction of nutrient by plant from 113 to 155 DAT, corresponding to harvesting period. For all treatments, the period of largest extraction of nutrient by plant occurred from 113 to 155 DAT, which coincides with the highest accumulation of dry matter. This period includes extraction of 57 to 64% of the total accumulated for N according to treatment and 57 to 63% for K. Plant nutrient distribution showed that fruit is the largest sink of N, K and P. After the results obtained show that the harvest period is the most impact show in the production of dry matter and nutrient uptake by the plant. Under conditions of development experience, NK levels showed no effect on dry matter and nutrient uptake in the periods of vegetative growth, fruiting, ripening and early harvesting.

Keywords: sand-mulch, NK rates, growth, greenhouse, fertirrigation
 

The use of disinfected urban wastewater (RW) for horticultural crops irrigation in Mediterranean area, could contribute to reduce the fertilizer input, water resources consume and also the contamination. The high nutrient content of water RW requires the determination of nutrient demand for development a technical efficiency. This work studies the influence of different levels of NK fertigation with purified wastewater obtained from the Almería city (Spain), on yield, fruit quality and macronutrient uptake in pepper. The experiment was conducted in a polyethylene greenhouse ‘Aifos’ pepper crop, on a sand-mulched sandy loam soil and trickle irrigation. The experimental design was randomized blocks with four blocks. There were six treatments: two non-fertilized controls (RW and ground water, GW) and four NK levels (N₁K₁, N₁K_1.5, N_1.5K₁ and N_1.5K_1.5). N₁K₁ is the recommended rate corresponding to 125 kg. ha^-1 of N and 193 kg. ha^-1 of K and average nutrient concentrations: 9.8 mM of N (NO₃-+ NH₄+) and 5.4 mM of K. The results show that production parameters were equal in non-fertilized RW irrigated plants than in those irrigated with GW water, resulting in low commercial production. The fertigation with N₁K₁ had given yield parameters similar to RW control. Significant increase of marketable yields, number and weigh of fruit was recorded with N_1.5K_1.5, N₁K_1.5 and N_1.5K₁ levels compared to RW control. The NK level had no effect on fruit quality attributes (pH, fruit firmness, total soluble solids and tritable acidity of juice). Nutrients uptake by plant followed the same order in all treatments K> N> Ca> Mg> P. The treatment N_1.5K_1.5 showed the highest uptake of N and P, being the K uptake similar to N₁K_1.5 and N_1.5K₁ treatments. Absorption efficiency of N and K was higher than 90% in N_1.5K_1.5, N₁K_1.5 and N_1.5K₁ treatments.

Keywords: sand-mulch, NK rates, pH, fruit firmness, total soluble solids and tritable acidity, N, P, K, Ca and Mg uptake.
 

The experiment was conducted in 2 polyethylene greenhouses located in Almería (Spain) with ‘Mantra’ green bean crop (Phaseolus vulgaris ssp. volubilis), on a sand-mulched loam soil with trickle irrigation. The experimental design was a two-factorial with four replications per treatment. The treatments applied were two Organic Matter levels (0.58% and 1.65%) and two System Crops (Organic and Integral). Fertigation levels were: 6.8 gm^-2 N, 1.4 gm^-2 P and 10.7 gm^-2 K following Regulation (CEE) Nº 2092/91 (Organic Crop System) and Specific Regulation of Green Beans Integrated Crop Production (BOJA) Nº 10/01. Treatments established were: E₁: Organic Crop System (OCS) under Low Organic Matter Soil (LOMS). I₁: Integrated Crop System (ICS) under LOMS. E₂: OCS under High Organic Matter Soil (HOMS). I₂: ICS under HOMS.

Plant extraction was analysed in different plant fractions (fruits, leaves and stems). The nutrients analysed were Total N, P, K, Ca and Mg.  Nutrient extraction was significantly higher under ICS (11.1 gm^-2 N, 3.6 gm^-2 P, 13.0 gm^-2 K, 9.6 gm^-2 Ca and 3.0 gm^-2 Mg) than  OCS (7.8 gm^-2 N, 2.2 gm^-2 P, 8.3 gm^-2 K, 7.1 gm^-2 Ca and 2.2 gm^-2 Mg).

Extracted nutrient levels do not show significant differences between Organic Matter treatments. Nutrient Use Efficiency was similar under all treatments. Also the N, P, Ca and Mg patterns between organs were unaffected by treatments. In general, N fruits and leaves extractions were similar (around 40%), and higher than N stems. P leaves extraction was higher than in stems and fruits. Ca and Mg extractions were the highest in leaves (70% and 50%), intermediate in stems (20% and 30%) and the lowest in fruits (10% and 20%). K distribution pattern between organs were affected by treatments. K fruit extraction under ICS was significantly higher (39%) than OCS (35%), while K stem extraction under OCS was higher (40%). Similar distribution pattern were found related to Organic Matter Level. K fruit extraction under HOMS was higher, while K stems extraction was higher under LOM.

 

Nitrogen is considered as the main nutrient that affects to vine vigour and must and wine quality. However, exits scarce information about the N-NO3- adequate levels for vineyard soils in semiarid climatic conditions. The aim of this study is realized a first evaluation of the relationship between the soil N-NO3- availability and vines N nutritional status, yield components, and must quality.
We selected 14 vineyards of Tempranillo (Vitis vinifera L.) cultivar grafted on Richter 110, with an age ranging from 10 to 25 years and situated in platforms of the Lower Najerilla area (D.O.Ca. Rioja). The plots are located in an area that covers approximately 1200 ha of vineyards; therefore there are not climatic variations between the plots selected. The vineyard soils have pH>8, with low to medium carbonate content, loamy texture and organic matter contents <2 %.
The vineyards soils were sampled at 0-15 and 15-45 cm soil depth at vineyards flowering stage (June 29, 2010) (when the vines nutrient demand is highest) and the N-NO3- extractable was determined. Leaves were sampled from the opposite position to the 2nd clusters at veraison stage (August 23, 2010). The N content was determined in blade and petiole tissues with a CNS analyzer elemental. One day before harvest, 1500 berries were collected in each vineyard and anthocyanins and polifenols content were determined in the must. The grape yield per vine and weight bunch were determined at harvest (October 2010) and the shoot weight per vine was determined at mid-November as vigour parameters.
The soil N-NO3- was correlated with the N content in blade and petiole tissues. Also the soil N-NO3- had correlations with yield parameters. Respect to the must, the soil N-NO3- was negatively correlated with anthocyanins and polifenols content, so high soil N-NO3- content could decrease the must quality.
Therefore, in our conditions, the determination of the soil N-NO3- available at vine flowering could be an indicator of vine N nutritional status, potential yield and must quality. These preliminary results indicate that further study is required to establish adequate soil N-NO3- levels to obtain must of higher quality.

Strawberry production is usually obtained in Spain in sand substrate and fertigated cultures. Micronutrients are frequently applied as sulfate salts or EDTA chelates. Metals from sulfates precipitate even at low-neutral pH, reducing their availability. EDTA is recalcitrant, so the concern about the environmental fate of EDTA applied in agriculture has risen. In this work, it has been evaluated the efficacy of two alternative chelates of EDTA: the biodegradable IDHA, with similar structure, and a combination of regioisomers o,o-EDDHA and o,p-EDDHA to provide iron, manganese, zinc and copper. Doses were split according to the chelates stability in three or six weekly applications. Experiment started the second of January. The foliar analyses were done at 31, 64 and 121 days after the first application. Foliar analysis, in comparison with chlorophyll indices based on SPAD measurement, was used to evaluate chelate efficacy. SPAD values did not show differences among treatments while SPAD increment was higher in IDHA treatment during the whole assay. However, differences were found among the three chelates based on foliar analysis. The treatment based on EDDHA isomers showed a better Fe content on the first period while IDHA showed better results at the end. No differences were found on Mn analyses among treatments. Zn nutrition was higher in EDDHA and EDTA treated plants and in the case of Cu for EDTA followed by EDDHA and IDHA. SPAD index was insufficient to evaluate the treatments while the foliar analysis was the most adequate test to evaluate differences among the three chelates. Based on it, we can conclude that EDDHA mix isomers is the better alternative to EDTA in strawberry in the studied conditions, although the biodegradable chelate IDHA showed good results in general and specially in Fe nutrition and a long lasting effect, as showed the SPAD increment values. IDHA and EDDHA are good alternatives for recalcitrant EDTA chelates.

Polycyclic Aromatic Hydrocarbons (PAHs) are a family of compounds classified as Pollutant Organic Persistent, hazardous for environmental and human health. These are ubiquitous and they are found in agricultural ecosystems in different matrices such as soils, plants and different organic amendments. Spent Mushroom Compost (SMC) is employed for soil bioremediation and environmental research. On this paper, four solvents (acetone:CH₂Cl₂ 1:1 mixture; acetone:hexane 1:1 mixture; methanol and acetone), among those already used as PAHs solvents, were chosen to be tested with two extraction methodologies (ultrasonic extraction and mechanical shaking). All extracted PAHs were identified and quantified by HPLC-PDA. Certified soil CRM141, containing 16 PAHs listed in the US EPA priority list, was used to validate the above mentioned methodologies. Mechanical shaking procedure was validated and selected since all detected and quantified PAHs were within CRM141 prediction interval and less variability data than ultrasonic extraction was obtained for all tested solvents.

Once mechanical shaking methodology was chosen, Fluorene (Flu), Phenantrene (Phe), Anthracene (Ant) and Pyrene (Py) standards were added on fresh (60% of moisture) and dried SMC. Mechanical shaking procedure were carried out over 24 hours and 1 month later, to avoid PAHs degradation and to provide PAHs interaction with solid matrix respectively.

PAHs mechanical shaking extraction over dried SMC showed large recovery percentages for all tested solvents. PAHs extracted from fresh SMC showed not biodegradation after 24 hours. Acetone:CH2Cl2 (1:1), methanol and acetone employed over fresh SMC obtained less recovery percentage than over dried SMC. Acetone:hexane (1:1) obtained recovery percentages higher than 80% and not showed recovery decrease over fresh SMC. Results indicate that is not necessary a dryness step previous PAHs extraction if acetone:hexane (1:1) mixture solvent is employed.

Proposed methodology for PAHs extraction includes mechanical shaking of fresh compost with acetone:hexane (1:1) solvent mixture and quantification by HPLC-PDA.

Synthetic chelates such as EDDHA have shown their efficacy to correct iron chlorosis on crops grown on calcareous soils. Several parameters, such as Fe(III) concentration, SPAD index, yield and size fruit, etc., are bibliographically described to be used to evaluate their efficacy however the relationships among themselves and the method variability are little known.
The aim of this study was to examine both coefficients of variation and coefficients of correlation when several nutritional status indexes are compared.

 

Three iron chelates plus additional treatment without any Fe(III) exogenous source were applied on commercial nectarine grove during two consecutive agronomic productive cycles. Data from 13 nutritional status indexes measured throughout field trial were compared (related to Fe(III) concentration in leaves and flowers, SPAD index, Fe/Mn ratio and yield and size fruit). Coefficients of variation (as dimensionless number) were statistically compared taking into account that all data from every nutritional status index were entered as repetition regardless Fe(III) source, sampling time, agronomic cycle. Additionally Pearson’s correlation coefficient was analyzed by comparing mean values from all nutritional status indexes two a two.

 

Statistical analyses, ANOVA and Pearson´s correlation coefficient, were performed with SPSS statistical software.
Coefficients of variation of all nutritional status indexes were lower than 30% that is associated with increased experimental variability. Coefficient of variation from fruit caliber and SPAD index showed the lowest values. No differences between coefficients of variation from Fe(III) concentration in leaves and Fe in flowers are found. Positive, larges and significant correlations are found between Fe/Mn ratio, Fe content in leaves and flowers and SPAD index and among all yield parameters. Since a lot of methods are used for nutritional status assessment, statistical methodology is necessary to know the dispersion and relationship themselves.

Potassium deficient fertilization resulted in significant decreases in the K concentration of plants in both soils. Highest levels of K  were found for the N2P2K3 treatment in soil „A” and for the N1P1K3 treatment in soil „B” at the stage of tillering. Except of K0 treatments, K concentrations of barley leaves were higher in soil „A” than in soil „B” at the stage of full bloom. However, K concentrations of blooming ears were lower in soil „A”, except of N1P1K2 treatment. It was found that amounts of potassium taken up by whole barley plants were higher in soil „A” at each growth stages studied, due to the more favourable soil texture and nutrient supplying capacity of this soil.

Plant nutritional diagnosis requires specific reference levels for each variety which faithfully reflect the nutritional status of the crop. A vine nutritional survey was undertaken in the Rioja appellation, in north-eastern Spain. The survey method was used to establish Preliminary norms for its use in the diagnosis and recommendation integrated system (DRIS) to be applied to the nutritional diagnosis of blade and petiole tissues of Vitis vinifera L., cv. Tempranillo tinto on Richter-110 rootstock. These DRIS norms were generated from data obtained throughout twelve years (2000-11) from 166 vineyards. The obtained database includes data from the different altitudes, soil types, cultural practices, and climatic conditions within the Rioja appellation. The training systems were Goblet, Guyot, and Double Cordon Royat espalier pruning. In general, vineyards had a dry farming irrigation regime and a homogeneous mechanical tilling. Nitrogen, P, K, Ca, and Mg were analyzed in blade and petiole dry tissues sampled at flowering and veraison. Vineyards with phytosanitary damages or troubles at flowering were ruled out. Ratios among nutrients were established for blade and petiole at flowering and veraison comparing high and low quality populations, both selected from production and must quality criteria, by mean of Student's t-test for the comparison of means.

Finally, DRIS norms for blade and petiole at flowering and veraison are proposed for Tempranillo tinto grapevine in the Rioja appellation.

 

We concluded that the effect of returned plant residues depends on the species in the sward as well as on the intensity of managing the grassland.

Generally, the occurrence of Fe deficiency symptoms (depressed growth and leaf chlorosis) in plants is known to be related to the contents in calcium carbonate and available Fe forms of soil. The results of investigation of the calcareous soils of Cemovsko polje under vineyards as well as petioles (taken at full flowering) are shown in this paper. Beside basic soil parameters such as pH, total carbonates, active carbonates and humus (organic matter), the content of exchangeable Ca (NH4CH3COO-Ca) and available Fe (DTPA-Fe) were determined in upper (0-30 cm) and underlying soil layer (30-60 cm). As expected the both of soil layer had very high concentration of exchangeable Ca (ranged 1131 – 1698 with average 1484±192 mg/100g for upper, and 1520 – 1820 with average 1665±84 mg/100g for underlying layer). From the aspect of available Fe (ranged 7.3 – 22.3 with average 10.7±4.8 mg/kg for upper, and 3.1 – 7.8 with average 5.6±1.5 mg/kg for underlying layer) ones were relatively poorly supplied according to Ankerman.

The concentration of Ca in petiole was in optimal range 1.67 – 2.70% (2.16±0.33) level, but of Fe was in range of low concentrations 19.32 – 25.80 mg/kg (22.86±2.40), corresponding to soil results. The obtained results are spatially represented by means of GIS technology.

In North America soil pH and extractable cations are dominate soil test methods performed in commercial testing labs. Although of interest Cation Exchange Capacity (CEC) is performed on a limited basis due to the complexity of the test and cost. Estimation CEC methods are often used on neutral to acid soils, but fail on soils containing calcium carbonate. The objectives of this study were to: (i) evaluate four extraction methods (1.0 N NH₄OAc buffered pH 7.0, Mehlich 3, 0.01 M SrCl₂, and silver thio urea) for their effectiveness in quantifying soil extractable cations and CEC. An additional evaluation was performed to evaluate 0.01 M SrCl₂ for the determination of soil pH, NO₃-N, extractable aluminum (Al) and sulfur. Results indicate good agreement with 0.01 M CaCl₂ of forty soils selected from the ALP proficiency program and with 0.01 M SrCl₂ and for 1.0 N KCl extractable NO₃-N, calcium phosphate extractable sulfur and Al using 1.0 M KCl. Results for extractable cations (i.e. K, Ca, Mg, and Na) indicate SrCl₂ had lower recoveries relative to NH4oAC and Mehlich 3 extractants, and was variable dependent on the soil. NH4OAC buffered to pH 7.0 resulted in extraction of Ca from free lime on soils with greater than 1% CaCO₃. Estimation of CEC using SrCl₂ was in good agreement for soils cation replacement methods for soils with CEC less than 7.0 cmol kg^-1 however poor agreement was noted on soils higher CEC values.

Two 3-year (2007 to 2009) field experiments were conducted on canola (Brassica napus L.) and wheat (Triticum turgidum L.) at Melfort Research Farm, Saskatchewan, Canada, to determine the influence of different combinations of three N rates (40, 80 and 120 kg N ha^-1), three urea coatings [(non-coated/treated urea (urea), urea coated with polymer (called ESN), and urea treated with Dicyandiamide (DCD) and N-(n-butyl) thiophosphoric triamide (NBPT or Agrotain^TM) called SuperU in 2007, or with NBPT or Agrotain^TM called AgrotainU in 2008 and 2009], and two methods of placement (side-banded N and seedrow-placed N, with knives), plus a zero-N control, on seedling emergence, seed and straw yield, protein concentration (PC) in seed and N uptake in seed and straw. Side-banded N had no detrimental effect on seedling emergence for both crops. Seedling emergence was decreased with increasing N rate of seedrow-placed N for urea and SuperU or AgrotainU, especially for canola where reduction was noticed even at 40 kg N ha^-1 rate. Seedling emergence was lower with seedrow-placed N compared to side-banded N for urea and SuperU or AgrotainU, but usually little or no detrimental effect of seedrow-placed N on emergence for ESN. Seedling emergence, seed yield and N uptake were all generally greater with ESN than urea and SuperU or AgrotainU, when the fertilizers were seedrow-placed at high N rates. Protein concentration in seed increased with increasing N rate, but there was no effect of N source and N placement method on PC. The higher total N uptake in seed + straw but lower seed yield of canola with seed-placed N than side-banded N for urea and AgrotainU in 2008 suggested that N taken up by canola plants during the growing season from applied urea and AgrotainU did not translate into seed yield as effectively as from ESN.

The study on effects of vetiver grass and green manure management on properties of Map Bon, coarse-loamy variant was conducted at Khao Hin Son Research Station, Chachoengsao, Thailand.  The experiment was carried on split plot design in RCBD with 3 replications.  There were 2 main plots: with and without vetiver grass; 4 sub plots: without green manure, Vigna sinensis, Canavalia ensiformis, Dolichos lablab.  The experiment was carried on during March 2001 to April 2003.  The results showed that  treatments with vetiver grass caused the increment of organic matter, and also saturated hydraulic conductivity.  On the other hand, bulk density of topsoil and subsoil and soil hardness were decreased, while total porosity and available water capacity were not affected.  The use of green manure effects on soil hardness and saturated hydraulic conductivity that were better.  The treatments with vetiver grass and green manure also gave an increment of available water capacity of soil.

This study was undertaken to define main factors influencing changes in soil N-NO₃ and N-NH₄ during sample transport and storage before analysis. 14 agriculture topsoil samples from arable land were collected for the study. The soil samples represented major soil types and climatic regions in the Czech Republic. 17 different sample preservation methods were chosen for the investigation. Soils were analyzed immediately after delivery to the laboratory, after storing at 4°C up to 7 days, after freezing at -18°C, after drying at 20, 60, 105 and 200°C. The dried samples were analyzed immediately after drying and also after 2, 7 and 25 weeks of storage at the laboratory temperature. Changes of both studied nitrogen fractions at 4°C were found to be relatively slow and samples showed no statistically significant differences after storing up to seven days. For longer period of storage freezing was necessary. Drying of the samples always increased the content of N-NH₄. Nevertheless drying was found to be a possible alternative of sample preservation in the cases when the content of N-NH₄ was negligible and only determination of N-NO₃ was demanded. Drying at 105 – 200°C did not cause any statistically significant changes in N-NO₃ but lower drying temperatures resulted in statistically significant increase of N-NO3 content.

Switchgrass (Panicum virgatum L.) and sunflower (Helianthus annuus L.) are important energy crops (perennial and annual, respectively).

In this work, the uptake of N-NO₃ by switchgrass and sunflower plants as an index of soil quality improvement was studied in a pot experiment. A peat-soil substratum was used, receiving NO-₃–N up to a concentration of 44 ppm. Switchgrass variety Alamo and sunflower variety turbo were sown in each pot on June 28^th (2010) and a nutrient solution of ammonium nitrate at three levels was supplied to correspond to N dressings of 0, 80 and 200 kg N/ha. Upon harvest the average height of switchgrass and sunflower was 75 and 59 cm, respectively. Fresh weights reached 85 g for sunflower versus 36 g for switchgrass. The amount of NO^-₃ – N remained in the soil was lower in the switchgrass vs. sunflower pots, fluctuating at levels lower than 16.8 mg N-NO₃/kg soil. More detailed results presented in the paper demonstrate that switchgrass can be considered as a particularly environmental-friendly crop for biofuel production characterized by a great N-NO₃ adsorption rate and soil improvement characteristics.

The long term positive effects of cropping systems involving rotation with cover crops on soil properties and the environment are well recognized.

The present work concerns a 3-year field experiment focusing on two cropping systems including two energy crops such as maize and sunflower cultivated (May - September) on an infertile sandy soil, and Pisum sativum cultivated as cover crop after the harvest of the energy crop (e.g. November - April). The cover crop was either harvested or incorporated in the soil before the sowing of the energy crop. The experiments were conducted in the vicinity of Trikala, western Thessaly (central Greece) in the years 2007 through 2009.

Soil samples from two soil layers, e.g. 0-20 cm and 20-40 cm, were collected at the onset and by the end of the experiments; they were analyzed for soil physical and chemical properties such as bulk density, soil moisture properties, aggregate stability, water infiltration rate, total N, P, K, pH, C_aCO₃, organic matter, organic C, and EC. All data were subjected to analysis of
variance (ANOVA), using GENSTAT software.

The results demonstrated a paramount effect of pisum intercropping on the performance of the subsequent energy crop as reflected by the significant increase in nitrogen uptake, the nitrogen use efficiency (NUE) and finally the increase in yield and biomass production under similar or even lower fertilization rates. These results are particularly important for the cultivation of less fertile soils such as sandy soils, which can be put in use for the production of energy crops such as maize and sunflower that are characterized by high nutrients and particularly nitrogen demand.

 

Keywords: Organic C, total N, C:N ratio, cover crops, pisum, Greece

In the present work the effect of Zeolite-Bentonite mixture on the improvement of soil quality and the biomass production of energy crops was investigated.

For the purpose of the study two different soil types, e.g. peat and sandy loam were used in a pot experiment, receiving NO^-₃ – N up to a concentration of 44 ppm. Half of the pots received the zeolite-bentonite mixture at range 3:1. Two different energy plants such as switchgrass (Panicum virgatum L.) and sunflower (Helianthus annuus L) were sown in each pot on June 28^th (2010) and a nutrient solution of ammonium nitrate at three levels was supplied to correspond to N dressings of 0, 80 and 200 kg N/ha.

The results showed that the zeolite-bentonite mixture performs a positive effect on soil denitrification as well as on the crop biomass production. However, more efforts are required before the proper ratio of the mixture can be established, so that both satisfactory crop yields along together with denitrification and soil improvement may be realized.

Washingtonia robusta (Mexican Fan Palm or Mexican Washingtonia) belongs to Arecaceae Family. This palm tree is native to northwestern Mexico (western Sonora and Baja California Sur). It can grow to 30 m tall and its leaves have a petiole up to 1 m long, and a palmate fan of leaflets to 2 m long. It is grown as an ornamental tree and requires full sun for its growth and permeable soils with high nutrient content. However, this plant can also grow in poor soil and tolerates low temperatures (hardy to – 5ºC) and water deficit. Washingtonia robusta is often pruned every 3 to 4 months, which produces a higher growth rate. This agricultural practice generates a great volume of pruning waste, what is generally disposed of in landfills.

 

Therefore, the aim of this work was to carry out the characterization of some agricultural and industrial parameters in the Washingtonia robusta pruning waste, in order to evaluate their capacity for agricultural use and for the manufacturing of insulating board employed in the building sector.

 

In this experiment, three different particle sizes (> 0.25, 1-2 and 2-4 mm) of the Washingtonia robusta leaf petiole were evaluated on total nitrogen; total organic carbon; bulk density; total pore space; air capacity; easily available water; water buffering capacity; total water holding capacity, shrinkage, macro and microelements. Moreover, thermal conductivity, bending strength, internal bonding strength and screw holding strength were determined in boards manufactured with three different particle sizes (> 0.25, 1-2 and 2-4 mm) of this pruning waste.

 

Respect to agricultural value, the Washingtonia robusta pruning waste had low macro and microelement contents, high C/N ratio values (C/N ratio > 120) and the majority of the studied physical properties were not inside the interval of values for an ideal substrate. On the other hand, the physical and mechanical properties of the fibreboards from the Washingtonia robusta pruning waste were appropriate according to the EN standards for fibreboards. Also, these Washingtonia robusta fibreboards presented properties similar to those of the wood-based composites as well as a higher insulating capacity.

 

Keywords: Washingtonia robusta pruning waste, Growing media, Manufacturing of fibreboard

The increasing demand for growing media for greenhouse horticultural uses, the increasing new uses of substrates and the scarcity and high price of the traditional sources like peat in Mediterranean countries drive the research into the use of new materials as soil-less substrates. In the last decades, intensification in the animal production and an increase in the size of the animal production units have been produced in the developed countries. This fact implies a great generation of animal manures that can constitute an environmental risk, if not managed properly. Nowadays, anaerobic digestion is one of the methods that are gaining interest to manage the wastes generated by livestock production. This treatment transforms organic wastes into two products: a source of renewable energy (biogas) and a potential fertiliser, the digested material (digestate). With the separation of the digestate into a liquid and a solid fraction, the latter can be composted in order to obtain valuable and marketable end-products for agriculture.

This work was conducted to study the feasibility of using a compost elaborated with the solid fraction of a digestate obtained after the co-digestion of cattle manure and maize-oat silage (SDM) as component in the formulation of growing media in horticultural seedlings, replacing part of the commercial peat. Three different vegetable species were selected in relation to their salt-sensitivity: the less sensitive being tomato (Lycopersicon esculentum Mill.), the moderately salt-sensitive being melon (Cucumis melo L.) and the most salt-sensitive being pepper (Capsicum annum L.). The proportions of compost substitution in the mixtures elaborated with peat were 25%, 50% and 75% v/v compost. Pure peat was tested as control treatment (P). The treatments (growing media) of this experiment were established in a fully-randomised design with three replicates per treatment (one tray per replication). Germination was performed in an air-conditioned chamber at 27 ± 1 °C and 90-95% relative humidity during different periods of time depending on the species. The percentage of germination was determined by counting the number of germinated seeds after 48 h from seeding. Then, the trays were placed on rails in an unheated polyethylene-covered greenhouse with natural daylight conditions until commercial transplanting size. Physical, physico-chemical and chemical analyses of the different mixtures were carried out. Parameters such as plant height, fresh and dry weight of seedling, root morphology, seed germination, macronutrient (N, P, K, Ca, Mg), and micronutrient (Fe, Cu, Mn, Zn) contents were also determined. In general, the addition of SDM to the growing media produced an increase in the pH values, salt contents, macro and micronutrient concentrations and in the air capacity, as well as a decrease in the water holding capacity and in the organic matter contents in comparison to control treatment.

Keywords: digestate, compost growing media, seedling production, tomato, melon, pepper

Iron‐deficiency‐induced chlorosis is a widespread nutritional disorder in grapevine, in particular on
calcareous soils. A solution of the problem could be the utilization of Fe‐fertilizers directly supplied
through foliar spray because it might be more efficient than soil application in increasing yield and
improving Fe status of vines.

Two iron chelates (Fe‐EDTA and Fe‐EDDS), an iron complex (Fe‐Lignosulphonate) and an iron salt
(Fe‐Sulfate) were foliarly applied on a mature Tempranillo tinto (Vitis vinifera L.), grown on a soil
with a large active limestone content (9.25% at the 30‐60 cm deep), and compared to a control
treatment. Five vines per treatment were chosen. A hundred milliliters of each iron treatment (5
mM) was spray on adult leaves (treated), while young leaves (untreated) were covered so iron
translocation could be studied. Treatments were repeated once after two weeks.

Treated and untreated leaf samples were taken just before treatments application and after four
weeks. Micronutrient content (Fe, Mn, Cu and Zn) were determined by AAS and Fe/Mn ratio
calculated as iron nutrition index. SPAD index was measured weekly throughout field trial on both
treated and untreated leaves.

No differences were found on Fe(III) concentration before the iron fertilizer application. All iron
treatments supplied significantly more Fe(III) than control treatment when Fe(III) concentration
from treated leaves was determined. Fe/Mn ratio from all iron treatments was significantly higher
than that of control treatment . Similarly, untreated young leaves from vines treated with Fe‐EDTA
and Fe‐Sulfate shown significantly higher Fe(III) concentration (61.1 and 60.1 mg Kg^‐1) than that of
control treatment (48.3 mg Kg^‐1). Fe/Mn ratio was higher from Fe‐EDTA treatment (0.44) that for
the rest of the iron treatments (p =0.07). The proposed methodology is valid to assess the Iron
translocation rate from adult to young leaves when foliar fertilization is applied.

Twenty-four sites in northern Tasmania on Oxisols formed on Tertiary basalt were sampled in 1997, 2005 and 2010.  During this time the sites were farmed in a variety of ways.  Until 1997, 9 sites had been under pasture and 9 had been continuously cropped to a mix of vegetable, cereal and other cash crops for at least the previous 10 years.  Six sites had a pre-1997 history of mixed cropping and pasture.  By 2010 only 3 sites remained under continuous pasture, the other 6 having had at least one crop since 1997.  Four sites which were previously continuously cropped had some pasture between 1997 and 2010, while an equal number of previously mixed cropping and pasture sites were cropped for at least 11 of those 13 years.  Average organic carbon (OC) concentrations across all sites and both sample depths (0-150 mm and 150-300 mm) decreased from 4.0% in 1997 to 3.5% in 2005 and 3.3% in 2010 (P<0.001).  Average OC was higher at 0-150 mm (4.1%) than at 150-300 mm (3.1%) (P<0.001), but there was no interaction between year and depth.  Soil pH in water showed the opposite trend to OC, increasing with time (P<0.001) from 6.0 in 1997 to 6.2 in 2010.  This reflects the consistent use of calcite and dolomite lime in Tasmanian farming because the natural pH of these soils is less than 5.5.  Exchangeable calcium and magnesium were also higher (P<0.02) in 2010 compared with 1997.  Bicarbonate-extractable phosphorus (P) averaged across both depths increased (P<0.001) steadily from 77 mg/kg in 1997 to 95 mg/kg in 2005 to 126 mg/kg in 2010.  The average topsoil concentration (130 mg/kg) was significantly (P<0.001) higher than the concentration at 150-300 mm (69 mg/kg).  There was no year by depth interaction.  At the 5 sites that remained under cropping throughout the study, average 2010 OC in the topsoil was 3.2%, a decrease of 0.5% since 1997; pH was unchanged at 6.4; while bicarbonate-extractable P increased by an average of 73 mg/kg, to 211 mg/kg.  For the 3 sites that remained in pasture the corresponding topsoil changes were 0.3% less OC to an average of 4.8%; pH 0.4 units higher at 6.0; and 41 mg/kg more extractable P to an average of 99 mg/kg.  At the 6 sites converted from continuous pasture to mixed cropping and pasture the average 2010 topsoil OC was 4.5%, a loss of 1.3%; pH increased by 0.5 units to 6.1; and extractable P increased by 35 mg/kg to 97 mg/kg.  Similar trends were evident in the subsoils.  There was a highly significant (R²=0.82) exponential relationship between topsoil OC in 2010 and the number of years each site had been cropped during the 38 years, 1972-2010, for which reliable records were available (OC = 4.933e^-0.018years).  This contrasts with a corresponding linear relationship between the 1997 topsoil OC data and cropping frequency to 1997, and suggests the rate of decline in OC decreases as cropping history increases beyond 30 years.  Further monitoring is needed to see whether OC equilibrium will establish.  These results indicate that Tasmanian farmers continue to increase the pH and P fertility of their soils, regardless of land use, and that the increasing economic pressure to crop these soils comes at the expense of soil carbon.

Appropriate evaluation of phosphorus (P) availability in soil is a prerequisite for ensuring the productivity and long-term sustainable management of agroecosystems. This study examined the influence of four levels of P fertilization (0 to 26.2 kg P ha-1 year-1)  on soil-P status, P-uptake and dry matter (DM) production of an extensive permanent meadow (2 cuts year-1) in the Swiss Jura. Soil (0–0.05, 0.05–0.10, 0.10–0.20 m) and plant samples were taken from a long-term fertilizer experiment established in 1992 by the Swiss Research Station Agroscope ACW in a Cambisol of low P content. Soil analyses included total-P, organic-P, inorganic-P, available-P (H2O-P, NaHCO3-P, AAE-P) and soil-P saturation (DPS). DM-yield and plant-P concentration were analyzed in July and September. The P balance between P-uptake and P-input and P nutrition index (PNI) were evaluated as well. The 15-years P-balance was positive only in the treatment receiving 26.2 kg P ha-1 year-1. The DM-yield was significantly lower in the no-P treatment where the amounts of soil available-P extracted by H2O, NaHCO3 and AAE (acetate ammonium EDTA) were, in 2008, respectively 1.9, 12.5 and 8.9 mg P kg soil-1 . Correspondingly, the estimated values for optimal-P, using an quadratic-plus-plateau model, were 2.5, 17.2 and 19.2 mg P kg soil-1. The plant-P concentration was 1.4 g P kg DM-1 lower in the treatment receiving no P compared to the highest P treatment, whereas PNI were respectively 51 and 100%. This study  provides useful results to optimize P fertilization of mountain permanent meadows.

There were no significant differences between the farming systems, highlighting the indicator of costs per hectare. Yield levels were lower in organic farming; however, the cost per product unit and the market price were higher. None of the cropping systems proved to be viable without subsidies, the gross profit variations are primarily the results of the differences in the yields and market prices gut not that of the subsidies. In most of the models, organic farming seemed to be more profitable; however, the amount of organic extra price – with parallel of the reference literature – is not enough to achieve a higher profit level in each year. As the price advantage of organic farming is decreasing, the profitability of organic farming is basically affected by increased and balanced yields compared to conventional farming.

hough the potassium (K) status of the soil often relies only on its exchangeable K content, release from non-exchangeable K always contributes to plant nutrition. This process, as well as the opposite one, K fixation, are diffusion-controlled and thus depend on time. This study was conducted (i) to assess the influence of time (2 hours, 1 and 8 days) on soil K dynamics and (ii) to compare the soil ability for K release and fixation (β) estimated from sorption-desorption experiments with the soil fixation capacity estimated at two different K doses. The studied soil samples came from a long-term fertilizer experiment established in 1976 by the Swiss Research Station Agroscope-ACW in a Gleyic Cambisol. They correspond to two extreme K-treatments (i) no K applied, P applied in quantities equivalent to the off-take by the crops and (ii) K and P applied in quantities equivalent to the off-take with an additional supply of 166 kg K ha-1 y-1 and 26.2 kg P ha-1 y-1.

The equilibrium K concentration decreased and, conversely, the soil K buffer power (i.e. the soil capacity to resist a change in soil solution K concentration following a removal of K from, or an input of K into, the soil–plant system), β, and fixation capacity increased when the soil K content decreased. Time significantly influenced only the sorption-desorption curve and the release–fixation of the poorest soil sample. In this case, K buffer power, β, and fixation capacity increased with time. Fixation capacity and β were linearly related (r=0.92, P<0.01), but fixation capacity systematically overestimated β. A first-order model enabled to describe the time-series of exchangeable K during fixation capacity experiments. However, a parabolic diffusion model gave a better description.

One year old sour orange (Citrus aurantium L.) trees were subjected to four levels of sodium chloride salinity stress (control, 40mM, 80mM and 120 mM sodium chloride) for 60 days. At the end of the stress period plant growth was evaluated by measuring leaf, shoot and root dry weights, while carbohydrates, chlorophylls, lipid peroxidation and electrolyte leakage were also determined in leaves. Plant nutrient status was evaluated in leaf, shoot and root samples, while soil was also analyzed for nutrient content. Leaf turgor status was determined in order to assess water stress induced by salinity. Salt stress induced a significant accumulation of sodium and chloride in leaves, shoots and roots. Potassium and phosphorus concentration in leaves as well as iron and copper concentration in shoots were enhanced under salt stress. Inconsistent changes were detected concerning magnesium, zinc, manganese and copper concentrations in leaves. Soil electrical conductivity, sodium and chloride concentration increased with increasing salt concentration, while potassium concentration decreased. Sucrose and glucose concentration was significantly reduced under salt stress. Leaf and shoot dry weight was not significantly affected, while root dry weight decreased with salt stress. Chlorophyll concentration was also reduced under stress, maintaining though cell membrane integrity, based on lipid peroxidation and electrolyte leakage indexes. Based on leaf characteristics indexes, leaves’ water stress was negligible, even after two months under salt stress. Based on the present results, sour orange accumulate significant amounts of sodium and chloride ions, without affecting its growth, although the reduced carbohydrates in the leaves indicate probably a reduction of carbon assimilation rate, which in the long run could result in reduced growth.

The results of our research are essential for the interpretation of the changes happened in the water balance features (aquifer capacity and permeability) of soils polluted with surfactants.