Tamás Árendás

New environmentally friendly fertiliser advisory system, based on the data set of the Hungarian long‐term field trials set up between 1960 and 1995

Abstract Following the 25‐year intensive fertilisation practice in the country, two‐thirds of Hungarian soils became well or very well supplied with phosphorus (P) and potassium (K). As a consequence of both political and ecological changes in the late 1980s and early 1990s, fertiliser subsidies were withdrawn, and nitrogen (N) use has dropped to one‐fifth, one‐third, P and K use to one twenty‐fifth, one‐twentieth of the amounts used in the early‐mid 1980s. An enormous demand has risen for a new, cost saving, and environmentally friendly fertiliser recommendation system. The new system based on the results of the published long‐term field trial data in the period of 1960–1995 faces the new challenges.

Evaluation of Different Fertilizer Recommendation Systems on Various Soils and Crops in Hungary

The World Phosphorus Institute (IMPHOS) financed a 3‐year program for the testing of various Hungarian fertilizer recommendation systems [the four levels of the new Research Institute for Soil Science and Agricultural Chemistry (RISSAC)–Agricultural Research Institute (RIA) system, the Talajerőgazdálkodás integrated soil fertility management system, and the intensive MÉM NAK system developed in the late 1970s by experts from the Ministry of Agriculture and Food] when applied to three major crops (winter wheat, maize, spring barley) grown on three characteristic Hungarian soils (brown forest soil, chernozem, meadow soil). The first six treatments in the experiment represented a classical deficiency experiment, aimed at checking the correctness of the nitrogen–phosphorus–potassium (NPK)–supplying categories determined by the various systems. On all three soils and for all three crops, the IMPHOS experiments confirmed the basic principles of the new cost‐saving, environmentally friendly RISSAC‐RIA fertilizer recommendation system and the correctness of the methods used for calculating fertilizer rates. The new RISSAC‐RIA system resulted in good yields, on par with those obtained using the intensive MÉM NAK system, with total NPK rates that were sometimes as little as 40–60% of the intensive recommendations. Consequently, the greatest incomes per unit area were also achieved using the recommendations given by the new, cost‐saving, environmentally friendly RISSAC‐RIA system.

Changes in the photosynthetic efficiency of winter wheat in response to abiotic stress

The assessment of heat and drought tolerance is of primary importance in breeding programmes designed to improve heat and drought tolerance in cereals. Three winter wheat varieties grown in controlled growth chambers were exposed to heat (H) and drought (D) stress singly and in combination (H+D). The combined effects of H and D stress were much more severe than those of individual treatments for both physiological and yield parameters during grain filling. The chlorophyll content, effective quantum yield of PSII, net assimilation rate, transpiration, stomatal conductance and intercellular CO2 concentration were greatly reduced by H, D and their interaction. Grain yield decreased to a greater extent (48.3%) in Plainsman V, averaged over the stress treatments, than in Mv Magma (67.8%) and Fatima 2 (53.7%). The least decline was found in grain number, except in Plainsman V. Mv Magma tolerated heat stress better than Fatima 2. In terms of photosynthetic activity, Plainsman V showed better drought tolerance than Mv Magma. The results showed that changes in physiological properties during stress treatment are not always associated with changes in yield parameters, so a combination of methods may be needed to give a more precise picture of the stress tolerance of wheat varieties.

Crop Nutrient Status and Nitrogen, Phosphorus, and Potassium Balances Obtained in Field Trials Evaluating Different Fertilizer Recommendation Systems on Various Soils and Crops in Hungary

Based on correlations calculated from the database of long-term fertilization experiments carried out in Hungary between 1960 and 2000, a new, cost-saving, and environmentally friendly fertilizer recommendation system was developed. The aim of the new system is to apply the lowest possible nitrogen (N)–phosphorus (P)–potassium (K) rates required to achieve good yields and maximum income per unit area. The World Phosphorus Institute (IMPHOS) agreed to finance a 3-year program to test various Hungarian fertilizer recommendation systems (the new RISSAC-RIA [Research for Soil Science and Agricultural Chemistry‐Research Institute for Agriculture] system, the Talajerőgazdálkodás integrated soil fertility management system, and the intensive MÉM NAK [Department of Plant Protection and Agricultural Chemistry of the Ministry of Food and Agriculture] system) when applied to three major crops grown on three characteristic Hungarian soils. The first five treatments in the experiment represented a classical deficiency experiment, aimed at checking the correctness of the NPK supply categories determined by the various systems. On all three soils and for all three crops the IMPHOS experiments confirmed the basic principles of the new cost-saving, environmentally friendly fertilizer recommendation system and the correctness of the methods used for calculating fertilizer rates. In this article, diagnostic plant analysis, soil analysis data, and NPK balances obtained in the different recommendations are discussed. In most cases the plant NPK contents of all the recommendations exceeded the lower limits of the good NPK supply category for wheat and barley shoot as well as for corn leaf. Crop NPK contents in Talajerőgazdálkodás and MÉM NAK treatments (with greater recommended NPK doses) were most cases better than in the RISSAC-RIA treatments; however, the better crop NPK status did not result in extra grain yield in the former treatments. Taking into account that similarly high yields were obtained using the RISSAC-RIA system and the Talajerőgazdálkodás integrated system with much smaller NPK doses than those recommended by the intensive MÉM NAK system, it was more advantageous from agronomic, environmental protection, and economic points of view. Differences in PK balances correlated well with the differences in the measured soil ammonium lactate (AL)–PK contents after the third year of the experiment.

Genome-wide association study and genetic diversity analysis on nitrogen use efficiency in a Central European winter wheat (Triticum aestivum L.) collection

To satisfy future demands, the increase of wheat (Triticum aestivum L.) yield is inevitable. Simultaneously, maintaining high crop productivity and efficient use of nutrients, especially nitrogen use efficiency (NUE), are essential for sustainable agriculture. NUE and its components are inherently complex and highly influenced by environmental factors, nitrogen management practices and genotypic variation. Therefore, a better understanding of their genetic basis and regulation is fundamental. To investigate NUE-related traits and their genetic and environmental regulation, field trials were evaluated in a Central European wheat collection of 93 cultivars at two nitrogen input levels across three seasons. This elite germplasm collection was genotyped on DArTseq® genotypic platform to identify loci affecting N-related complex agronomic traits. To conduct robust genome-wide association mapping, the genetic diversity, population structure and linkage disequilibrium were examined. Population structure was investigated by various methods and two subpopulations were identified. Their separation is based on the breeding history of the cultivars, while analysis of linkage disequilibrium suggested that selective pressures had acted on genomic regions bearing loci with remarkable agronomic importance. Besides NUE, genetic basis for variation in agronomic traits indirectly affecting NUE and its components, moreover genetic loci underlying response to nitrogen fertilisation were also determined. Altogether, 183 marker-trait associations (MTA) were identified spreading over almost the entire genome. We found that most of the MTAs were environmental-dependent. The present study identified several associated markers in those genomic regions where previous reports had found genes or quantitative trait loci influencing the same traits, while most of the MTAs revealed new genomic regions. Our data provides an overview of the allele composition of bread wheat varieties anchored to DArTseq® markers, which will facilitate the understanding of the genetic basis of NUE and agronomically important traits.

New, Environmentally Friendly Wheat Fertilizer Advisory System for Hungary

Following the 25-year intensive fertilization practice in the country, two thirds of Hungarian soils became well or very well supplied with P and K. As a consequence of both political and ecological changes in the late 80’s and early 90’s, fertilizer subsidies were withdrawn, and N use has dropped to one fifth ar one third, and P and K use to one twentyfifth or, one twentieth of the amounts used in the early or mid-80’s. An enormous demand has arisen for a new, cost-saving, environmentally friendly fertilizer recommendation system. The new system — based on the evaluation of the results of long-term field trial data published in the period 1960–1995 — faces the new challenges.

Effect of nitrogen fertilization and genotype on the yield and yield components of winter wheat

Summary The effect of N fertilization on the yield, yield components, harvest index (HI), and chlorophyll content (SPAD (soil plant analysis development) index) of winter wheat cultivars was investigated in a long-term experiment in Hungary between 2006/2007 and 2008/2009. Maximal grain yield was reached at 80 and 160 kg · ha–1 N treatments, the higher N rate did not lead to a further yield increase in any of the years. A substantial year effect was observed for the yield and yield components. A negative correlation was found between grain number and thousand-kernel weight (TKW). Mv Verbunkos gave among the varieties the highest grain yield, grain number per spike, and SPAD value. There was a significant (P<0.001) positive correlation between the yield and the number of grains per square meter (r=0.85) and between the yield and the SPAD index (r=0.59). A significant (P<0.01) negative correlation was detected between the yield and the TKW (r=–0.44) and a positive correlation between the yield and the HI (r=0.51). Regression analysis revealed a significant linear relationship between the yield and the yield components (number of grains per square meter and TKW) at the various N levels.

New environment-friendly and cost-saving fertiliser recommendation system for supporting sustainable agriculture in Hungary and beyond

In the current economic situation the former, intensive fertiliser recommendation system is unfit to help Hungarian farmers in their fertilising practice. The aim of the new system has been to apply the lowest possible NPK rates required to achieve safe and high yields as well as allowing minimal agricultural NP losses to surface and subsurface waters. The new system was developed by using the correlations revealed by analyzing the results of long-term fertilisation experiments set up in Hungary between 1960 and 2000. Several field experiments as well as comparative analyses confirmed the correctness of the basic principles as well as of the methods of calculating fertiliser rates of the new system. An estimated amount of 3,200,000 € was saved for the Hungarian farmers in 2007 alone by giving recommendations for more than 160,000 ha arable land applying the new system.

Evaluation of the grain yield and quality potential of maize hybrids under low and optimum water supply levels

Oil rape is a valuable fodder because in early spring and late autumn it produces green forage used for the nutrition of domestic animals. It has been replacing sunflower and soy in colder and wetter regions. It is additionally advantageous because it leaves behind more nitrogen in soil, which is beneficial to other plants in plant rotation. There are some possible ways for the fixation of nitrogen in soil and they are as follows: by the means of oil rape straw ; by relatively long roots ; by the action of nitrogen bacteria, which perform the nitrogen synthesis within their root system, which is the case in some leguminous plants. Oil seed rape is expected to be wider used in crop rotation of West and Middle Europe, Croatia included. Due to this various sorts have been introduced and potential positive impacts have been studied in order to boost the process. This paper presents information on barley and wheat yield in case when they were sown after oil seed rape and corn. The aim of the research is to determine the presence of positive impacts upon the soil with special attention paid to a potential increase of nitrogen content after oil seed rape was grown. The preceding crops had statistically significant effect. Rape yield was significantly higher compared to the one with corn as preceding crops. Very similar results were obtained in 2007.The maize hybrids seed from three different FAO groups (FAO 400, FAO 500 and FAO 600) in four fractions (KO, KP, SO and SP) produced in two climatically different years (extremely dry 2000 and extremely wet 2001) had been different in quality and chemical composition. The effects of year, genetic specifity and seed fraction at the kernel mass, chemical composition (starch, proteins, cellulose, oil and moisture content) and seed vigour have been evaluated. The influence of agroecological conditions during two production years have been exposed at seed chemical composition and vigour indicators (cold test – CT and bulk seed electrical conductivity - EC). The genetic specificity and seed fraction had significant influence at all tested indices, with the exception of the influence of the fraction at the starch content

Growth analysis of winter wheat cultivars as affected by nitrogen fertilization / Wachstumsanalyse von Winterweizensorten in Abhängigkeit von Stickstoffdüngung

Summary Growth analysis helps explain the differences in yield and growth potential between cultivars in response to management practices and environmental conditions. The aim of the research was: (i) to investigate the effect of nitrogen fertilization on the growth and growth parameters of different wheat (Triticum aestivum L.) cultivars and (ii) to study the relationship between yield and growth parameters at the individual plant and plant stand level. In the two-factorial, split-plot experiment, the main plot was the nitrogen (N) treatment and the sub-plot was the cultivar. In response to N fertilization, the values of growth rate parameters increased up to the N160 treatment. The mean values of crop growth rate (g m-2 day-1) in the treatments were as follows: N0: 10.4, N80: 15.4, N160: 17.2 and N240: 16.3. The leaf area index, leaf area duration and especially the duration of the flag-leaf gave a good reflection of the effect of N fertilization. Multiple regression analysis demonstrated the significant effect of growth rates, size and duration of leaf area, biomass distribution and yield components on the yield. The results showed that understanding the growth of plants is important for optimizing management decisions.