scholarly journals Long-term experiments on chernozem soil in the University of Debrecen

2018 ◽  
pp. 357-369
Author(s):  
Péter Pepó

The impact of agrotechnical management practices (nutrient and water supply, crop rotation, crop protection, genotype) on the yields of winter wheat and maize and on the soil water and nutrient cycles was studied in long-term experiments set up in 1983 in Eastern Hungary on chernozem soil. The long-term experiments have shown that nitrogen fertilizer rates exceeding the N-optimum of winter wheat resulted in the accumulation of NO3-N in the soil. Winter wheat varieties can be classified into four groups based on their natural nutrient utilization and their fertilizer response. The fertilizer responses of wheat varieties depended on crop year (6.5–8.9 t ha-1 maximum yields in 2011–2015 years) and the genotypes (in 2012 the difference was ~3 t ha-1 among varieties). The optimum N(+PK) doses varied between 30–150 kg ha-1 in different crop years. In maize production fertilization, irrigation and crop rotation have decision role on the yields. The efficiency of fertilization modified by cropyear (in dry 891–1315 kg ha-1, in average 1927–4042 kg ha-1, in rainy cropyear 2051–4473 kg ha-1 yield surpluses of maize, respectively) and crop rotation (in monoculture 1315–4473 kg ha-1, in biculture 924–2727 kg ha-1 and triculture 891–2291 kg ha-1 yield surpluses of maize, respectively). The optimum fertilization could improve the water use efficiency in maize production. Our long-term experiments gave important ecological and agronomic information to guide regional development of sustainable cropping systems.

2016 ◽  
pp. 9-13
Author(s):  
Gergely Szilágyi

We tested the fertilizer reaction of four different winter wheat varieties in three different crop years, on chernozem soil, in long-term experiment. We examined the optimum fertilizer requirements and the maximum yield of the varieties. According to our results there were significant differences among the years: the yield of the winter wheat varieties changed between 1.4–6.1 t ha-1 in 2013, 3.8–8.6 t ha-1 in 2014 and 3.2–8.6 t ha-1 in 2015. The yield increasing effect of fertilization was significantly different in the tested years. The optimum level of fertilization was determined by, besides the genetic differences among the varieties, the crop year and the extent of fertilization. In milder winter months, due to the higher average temperatures, yields of winter wheat increased compared to an average crop year.


2002 ◽  
pp. 59-64 ◽  
Author(s):  
Péter Pepó

In sustainable (wheat) production plant nutrition supply and fertilization play decisive roles among the agrotechnical elements, because of their direct and indirect effects on other agronomical factors.In long-term experiments, we studied the roles of agroecological, genetic-biological and agrotechnical factors in the nutrient supply, fertilization and its efficiency in wheat production under continental climatic conditions (eastern part of Hungary, Trans-Tisza) on chernozem soil. Our results have proved that there are different (positive and negative) interactions among ecological, biological, and agrotechnical elements of wheat production. These interaction effects could modify the nutrient demand, fertilizer (mainly nitrogen) response of wheat varieties and efficiency of fertilization in wheat production.The optimum N-doses (+PK) of wheat varieties varied from 60 kg ha-1 (+PK) to 120 kg ha-1 (+PK) depending on cropyears, agrotechnical elements and genotypes. The winter wheat varieties could be classified into 4 groups according to their fertilizer demand, natural and fertilizer utilization, fertilizer response and yield capacity.Appropriate fertilization (mainly N) of wheat could affect both the quantity and quality of the yield. By using optimum N (+PK) fertilizer doses, we could manifest genetically- coded baking quality traits of winter wheat varieties and reduce quality fluctuation caused by ecological and other management factors. The efficiency of fertilization on different baking quality parameters (wet-gluten, valorigraph index etc) were variety specific (the changes depended on genotypes).Our long-term experiments proved that appropriate fertilization provides optimum yield, good yield stability and excellent yield quality in sustainable wheat production. We could this get better agronomic and economic fertilization efficiency with less harmful environmental effects.


Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1472
Author(s):  
Ilaria Piccoli ◽  
Felice Sartori ◽  
Riccardo Polese ◽  
Maurizio Borin ◽  
Antonio Berti

Agri-environmental indicators such as nutrient balance may play a key role in soil and water quality monitoring, although short-term experiments might be unable to capture the sustainability of cropping systems. Therefore, the objectives of this study are: (i) to evaluate the reliability of long-term experimental N and P balance estimates to predict real field (RF) (i.e., short-term transitory) conditions; and (ii) to compare the sustainability of short- and long-term experiments. The LTE-based predictions showed that crops are generally over-fertilised in RF conditions, particularly maize. Nutrient balance predictions based on the LTE data tended to be more optimistic than those observed under RF conditions, which are often characterised by lower outputs; in particular, 13, 44, and 47% lower yields were observed for winter wheat, maize, and soybean, respectively, under organic management. The graphical evaluation of N and P use efficiency demonstrated the benefit of adopting crop rotation practices and the risk of nutrient loss when liquid organic fertiliser was applied on a long-term basis. In conclusion, LTE predictions may depend upon specific RF conditions, representing potential N and P use efficiencies that, in RF, may be reduced by crop yield-limiting factors and the specific implemented crop sequence.


2013 ◽  
Vol 40 (1) ◽  
pp. 77 ◽  
Author(s):  
Mitchell B. East ◽  
J. Daren Riedle ◽  
Day B. Ligon

Context Monitoring populations of long-lived species requires continuous long-term efforts. This is especially applicable for species that have experienced declines range-wide. Aims Our study assessed the current status of a population of wild Macrochelys temminckii and compared the present results to those from a survey conducted nearly a decade ago. Methods Trapping in 2010–2011 was conducted on two creeks within the refuge, during the months of May–July. Capture data were compared with data collected by similar methods in 1997–2001. Key results The population structure of M. temminckii was dominated by juveniles, with few large adults or small juveniles detected and a missing size class was evident. Retrospective analysis of 1997–2001 data revealed that the population was likely to be in decline even then, despite high capture rates. Conclusions The M. temminckii population showed significant declines that indicated that the population had experienced stressors of unknown origin. The status of M. temminckii at the refuge is concerning, given the protection afforded this remnant population. Implications Short-term data from 1997–2001 indicated a healthy M. temminckii population, whereas longer-term data showed that the population has declined, resulting in significant demographic changes. Continued monitoring will be necessary to develop management recommendations and track the impact of implemented management practices. Longer-term monitoring of long-lived vertebrates is required to identify population trends.


2021 ◽  
Author(s):  
Elsbe von der Lancken ◽  
Victoria Nasser ◽  
Katharina Hey ◽  
Stefan Siebert ◽  
Ana Meijide

<p>The need to sustain global food demand while mitigating greenhouse gases (GHG) emissions is a challenge for agricultural production systems. Since the reduction of GHGs has never been a breeding target, it is still unclear to which extend different crop varieties will affect GHG emissions. The objective of this study was to evaluate the impact of N-fertilization and of the use of growth regulators applied to three historical and three modern varieties of winter wheat on the emissions of the three most important anthropogenic GHGs, i.e. carbon dioxide (CO<sub>2</sub>), methane (CH<sub>4</sub>) and nitrous oxide (N<sub>2</sub>O). Furthermore, we aimed at identifying which combination of cultivars and management practises could mitigate GHG emissions in agricultural systems without compromising the yield. GHG measurements were performed using the closed chamber method in a field experiment located in Göttingen (Germany) evaluating three historical and three modern winter wheat varieties, with or without growth regulators under two fertilization levels (120 and 240 kg nitrogen ha<sup>-1</sup>). GHG measurements were carried out for 2 weeks following the third nitrogen fertilizer application (where one third of the total nitrogen was applied), together with studies on the evolution of mineral nitrogen and dissolved organic carbon in the soil. Modern varieties showed significantly higher CO<sub>2</sub> emissions (i.e. soil and plant respiration; +23 %) than historical varieties. The soils were found to be a sink for CH<sub>4,</sub> but CH<sub>4</sub> fluxes were not affected by the different treatments. N<sub>2</sub>O emissions were not significantly influenced by the variety age or by the growth regulators, and emissions increased with increasing fertilization level. The global warming potential (GWP) for the modern varieties was 7284.0 ± 266.9 kg CO<sub>2-eq</sub> ha<sup>-1</sup>. Even though the GWP was lower for the historic varieties (5939.5 ± 238.2 kg CO<sub>2</sub>-<sub>eq</sub> ha<sup>-1</sup>), their greenhouse gas intensity (GHGI), which relates GHG and crop yield, was larger (1.5 ± 0.3 g CO<sub>2</sub>-<sub>eq</sub> g<sup>-1</sup> grain), compared to the GHGI of modern varieties (0.9 ± 0.0 g CO<sub>2</sub>-<sub>eq</sub> g<sup>-1</sup> grain), due to the much lower grain yield in the historic varieties. Our results suggest that in order to mitigate GHG emissions without compromising the grain yield, the best management practise is to use modern high yielding varieties with growth regulators and a fertilization scheme according to the demand of the crop.</p>


Agronomy ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 300 ◽  
Author(s):  
Pradeep Wagle ◽  
Prasanna Gowda

Adoption of better management practices is crucial to lessen the impact of anthropogenic disturbances on tallgrass prairie systems that contribute heavily for livestock production in several states of the United States. This article reviews the impacts of different common management practices and disturbances (e.g., fertilization, grazing, burning) and tallgrass prairie restoration on plant growth and development, plant species composition, water and nutrient cycles, and microbial activities in tallgrass prairie. Although nitrogen (N) fertilization increases aboveground productivity of prairie systems, several factors greatly influence the range of stimulation across sites. For example, response to N fertilization was more evident on frequently or annually burnt sites (N limiting) than infrequently burnt and unburnt sites (light limiting). Frequent burning increased density of C4 grasses and decreased plant species richness and diversity, while plant diversity was maximized under infrequent burning and grazing. Grazing increased diversity and richness of native plant species by reducing aboveground biomass of dominant grasses and increasing light availability for other species. Restored prairies showed lower levels of species richness and soil quality compared to native remnants. Infrequent burning, regular grazing, and additional inputs can promote species richness and soil quality in restored prairies. However, this literature review indicated that all prairie systems might not show similar responses to treatments as the response might be influenced by another treatment, timing of treatments, and duration of treatments (i.e., short-term vs. long-term). Thus, it is necessary to examine the long-term responses of tallgrass prairie systems to main and interacting effects of combination of management practices under diverse plant community and climatic conditions for a holistic assessment.


2009 ◽  
Vol 323 (1-2) ◽  
pp. 143-151 ◽  
Author(s):  
Xu Tang ◽  
Yibing Ma ◽  
Xiying Hao ◽  
Xiuying Li ◽  
Jumei Li ◽  
...  

2003 ◽  
Vol 51 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Z. Berzsenyi

The research agenda for crop science in the 21st century will depend largely on whether the present conditions regarding the global food surplus continue, or whether a food scarcity recurs. Crop production research is based chiefly on small-plot field experiments, the majority of which are either long-term experiments or experiments set up to investigate the specific agronomic responses of Martonvásár maize hybrids and wheat varieties. The sustainability of crop production is examined in long-term experiments. The agronomic responses of maize hybrids and wheat varieties are studied at various levels of biological organisation. Growth analysis facilitates the exact characterisation of agronomic responses and the grouping of response effects and types using multivariable methods. Continued experimentation coupled with crop simulation models and decision support systems are an ever more useful framework for analysing the complexity of agricultural systems.


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