Fulltext search in archive

Soils harbour enormously diverse bacterial communities that interact specifically with plants generating beneficial interactions between them. This study was the first approach to assess bacterial communities before sowing with three cotton genotypes, including both transgenic and conventional ones. The structure of bacterial communities was identified using the next generation sequencing analysis, ion torrent PGM (Personal Genome Machine™) sequencer technology, based on the V2-V3 16S rRNA gene region. Quantitative insights into microbial ecology pipeline were used to identify the structure and diversity of bacterial communities in bulk soil samples collected in the northeast of Mexico. Bulk soil textures and chemical properties, including most nutrients, were homogeneous in these bulk soil samples. Relative abundance analysis showed similar bacterial community structures. Dominant taxonomic phyla were Proteobacteria, Firmicutes, Acidobacteria, Actinobacteria, Gemmatimonadetes and Bacteroidetes, whereas the main families were Bacillaceae, Chitinophagaceae and Rhodospirillaceae with an abundance average of BS1 (bulk soil sample), BS2 and BS3 (24.85, 19.74 and 19.71%, respectively). Alpha diversity analysis showed a high diversity (Shannon and Simpson index) and a large value of the observed species found in bulk soils samples. These results allowed establishing the previous bacterial structural community in an unused soil before sowing it with a transgenic crop for the first time.

In this research, laser-induced fluorescence (LIF) technique combined with back-propagation neural network (BPNN) was employed to analyse different nitrogen (N) fertilization levels in paddy rice. Leaf fluorescence characteristics (FLCs) were measured by using the LIF system built in our laboratory and exhibited different FLCs with different nitrogen fertilization levels. The correlation between fluorescence intensity ratios (F685/F460, F735/F460 and F735/F685) and the dose of N fertilization was established and analysed. Then, the BPNN algorithm was utilized to validate that the different N fertilization levels can be classified based on the three FLCs. The overall identification accuracies of 2014 and 2015 were 90% and 92.5%, respectively. Experimental results demonstrated that the three FLCs with the help of multivariate analysis can be served as a helpful tool in the evaluation of paddy rice N fertilization levels. Besides, this study can also provide guidance for the selection of LIF Lidar channels in the following research.

The field experiment was carried out during 2004-2006. The aim of the study was to determine the influence of insecticides (Actara 25 WG - 0.08 kg/ha, Regent 200 SC - 0.1 L/ha, Calypso 480 SC - three rates: 0.05; 0.075;0.1 L/ha), used for controlling Colorado potato beetle, on total glycoalkaloid (TGA) content in potato leaves and tubers of three cultivars (Mors, Wiking, Żagiel). The insecticides significantly increased (Calypso 480 SC) or decreased (Actara 80 WG, Regent 200 SC) the TGA content in potato leaves, and increased TGA in tubers as compared with tubers harvested from the control. Leaves and tubers of cultivar Mors had the highest TGA contents, whereas Żagiel leaves and Wiking tubers had the lowest levels.

The purpose of the present studies was to determine the antagonistic effect of bacteria Bacillus spp. and Pseudomonas spp. towards selected fungi from the soil environment of carrot. Oats (Avena sativa L.), tansy phacelia (Phacelia tanacetifolia Bentham) and vetch (Vicia satica L.) were used as cover crops in the cultivation of this plant. In the traditional cultivation of carrot the population of bacteria was the smallest, while after the application of oats it was the largest. Laboratory tests showed that cover crops promoted the development of antagonistic Bacillus spp. and Pseudomonas spp. Irrespective of the experimental treatment, those bacteria were the most effective in limiting the growth and development of Fusarium oxysporum and Thanatephorus cucumeris (syn. Rhizoctonia solani), while being less effective towards Altenaria dauci and Alternaria radicina, and the least towards Sclerotinia sclerotiorum. The best total antagonistic effect of Pseudomonas spp. and Bacillus spp. towards the tested fungi was found after using oats and vetch, while the worst - in the traditional cultivation of carrot.

Alkali pretreatment of wheat straw was optimized by response surface methodology to maximize yields of fermentable sugars in subsequent enzymatic hydrolysis and to remove maximum lignin in order to improve rheological attributes of the media. The effects of pretreatment conditions on biomass properties were studied using the Expert Designer software. Concentration of sodium hydroxide and temperature were the factors most affecting pretreatment efficiency. At the optimum (80°C, 39 min, 0.18 g NaOH and 0.06 g lime per g of raw biomass), 93.1 ± 1.0% conversion of cellulose to glucose after enzymatic hydrolysis and 80.3 ± 1.2% yield of monosaccharides (glucose plus xylose and arabinose) from cellulose and hemicellulose of wheat straw were achieved.

It was assumed that the determination of the mineral nitrogen (N_min) content in the 0.01 mol/L CaCl₂ could rely on measurements of single form NO₃^--N, NH₄⁺-N or both, and even including other extractable nutrients. This hypothesis was verified based on some primary data from 17 fields: ten with oilseed rape and seven with maize as indicatory crops during three consecutive seasons in a production farm in Górzno, Poland. The contents of NO₃^--N, NH₄⁺-N, P, K, Mg and pH were measured in soil prior to the spring vegetation start and after a crop harvest (autumn). Phosphorus in spring and NH₄⁺-N in autumn, were variables discriminating against the number of clusters. It was higher in cropping sequences (CSs) with maize than with oilseed rape. The reliability of N_min determination and distribution between clusters in spring based only on NO₃^--N was fully corroborated for maize CSs. In autumn, irrespective of the CS, the decisive factor in N_min prediction and distribution over clusters was the NH₄⁺-N pool. This study resulted in the rating of CaCl₂ extractable nutrients, indicating their availability status, shortage or excess, on the background of the N_min temporary rating.

The study aimed at the evaluation of the accumulation and vertical distribution of different forms of phosphorus (P) in reference to phosphorus sorption properties subject to mineral (NPK), mineral-organic (NPK + M), and organic (M) fertilisation. It was carried out in a long-term experimental field in Skierniewice (Central Poland) conducted since 1923 under rye monoculture. Total P content in the M and NPK soil profile was similar and lower than in the NPK + M soil. The content of organic P in A_p and E_et horizons of both manured soils was similar and higher than in the NPK soil. The Langmuir P sorption maximum (S_max) in the studied soils ranged from 39.7 to 90 mg P/kg, while the Freundlich P sorption coefficient a_F ranged from 6.9 to 41.9 mg P/kg. Higher variability of parameters related to the binding energy from the Lanqmuir (k) and Freundlich (a_F) equations was determined between soil horizons than between the fertilisation systems. Nonetheless, in M and NPK + M soils, sorption parameters a_F and S_max and binding energy (k, b_F) were considerably lower than in the NPK soil. The content of water extracted P in manured soils was higher than in the NPK soil.

Transpiration efficiency (TE) is an important physiological trait associated with drought tolerance of plants. Currently, little is known about the grain sorghum TE and its dynamics with the age of plants. To compare the sorghum TE at different growth stages, four studies (two in the greenhouse and two in the growth chamber) were conducted under controlled environmental conditions. Plants were grown in lid-covered boxes and harvested at six-leaf, flag leaf, grain filling and maturity stages. The mean shoot TE values were 4.47 and 4.10 kg/m³ for two greenhouse studies, and 4.85 and 4.30 kg/m³ for two growth chamber studies, respectively. The shoot TE was not different among four growth stages within each study, suggesting that sorghum plants used the same amount of water per unit of biomass production for different growing periods. Because crops grown under dryland environments often run out of water during reproductive periods, result supports the ideas that soil water availability at later growth stages is crucial to achieve the yield potential of dryland sorghum.

For the purposes of assessment of long-term changes, two sets of Chernozems soil samples were analysed and compared in parallel: 'old' file samples obtained during the Soil Survey 1960-1970 in the former Czechoslovakia and a 'present' (2013) set of samples from exactly the same sites as the archive samples. The recently collected samples revealed worse qualitative parameters (lower humic acid to fulvic acid (HA/FA) ratios and higher colour quotient Q4/6 values) than the file samples, for all the localities. On the other side, the quantitative soil organic matter (SOM) parameters (oxidizable carbon (C_ox) and all its determined components) showed contrary results. The amount of total SOM at the same sites is higher now than it was about 50 years ago. It can be concluded that the current decline in SOM quality in Chernozems is partly compensated for by higher accumulation of SOM in the soils. All the analysed Chernozem samples were found to have much worse qualitative SOM parameters than the values mentioned for this soil type in the older literature. However, a comparison of the current data and the file data of Chernozem SOM quality can still be considered an open issue and require more complex research.

From 2012 to 2014 a field experiment was conducted on a podzolic soil. The aim of the study was to evaluate the yield and weed infestation of winter rye canopy depending on three biochar rates (10, 20 and 30 t/ha). The biochar was pyrolyzed from wheat straw at 350-650°C. After 12, 24, and 36 months from biochar incorporation into the soil pH, total carbon (C) and some elements in soil were determined. Additionally phytotoxicity of soil solid phase was assessed by the commercial toxicity bioassay - Phytotoxkit. The addition of biochar had a positive influence on grain yield of winter rye, which was related to the nutrient application in the form of biochar. The highest grain yields were obtained when biochar was applied at the rate of 20 t/ha. The air-dry weight of weeds in the rye crop grown in the biochar-amended plots was lower compared to the control plots. Incorporation of biochar into the soil at the rates of 20 and 30 t/ha caused a significant increase in the soil content of total C as well as of available P, K, Mg, Fe and B, relative to the control treatment. Moreover, the biochar-amended soil had higher pH because of the relatively high concentration in the biochar (pH_KCl 9.9). The assessment of substrate toxicity revealed that biochar applied at the rates of 10 and 20 t/ha had no negative effects on the germination of Lepidium sativum L.

The use of nitrogen (N) fertilizers in crops increases their yield but can modify their quality and lead to environmental problems by the emission of greenhouse gases (GHG). One of the strategies for mitigating this emission is the use of nitrification inhibitors (NI) as 3,4-dimethylpyrazole phosphate (DMPP). Additionally, the increased persistence of N after the application of NI can reduce the amount of fertilizer applied. A field experiment with lettuce was conducted in the Savanna of Bogotá. N was applied as ammonium sulphate nitrate (ASN 26%) at a rate of 70 kg N/ha and as the combination of ASN with DMPP (ENTEC® 26) at 50 and 70 kg N/ha rates. GHG emissions, soil parameters, lettuce yield, its components, N, nitrate and mineral elements contents were measured. With high soil nitrate contents, a standard dose of N fertilizer with DMPP maintained the yield and N content of lettuce, while it had no effect on GHG emissions. A reduction of 20 kg N/ha using DMPP was able to keep the yield meanwhile improving the quality of the crop due to a lower nitrate accumulation in lettuce leaves.

This study aimed at investigating the species composition and richness of the flora of abandoned sheep pens in comparison to their immediate neighbourhood. Field research was conducted in the Wielkopolska province of western Poland on 25 circular plots (20 m²) located in the middle of abandoned pens within sheep farms, paired with 25 reference plots established in nearby grasslands. Physicochemical properties of the topsoil were modified considerably by sheep in the past, so some effects continue to this day. Abandoned sheep pens did not differ significantly in plant species richness from control plots, but Urtica dioica, Galium aparine and Rumex obtusifolius, were significantly associated with sheep pens. Similar values of Shannon index and the low Jaccard index of similarity between plot types indicate that although these habitats are not richer in plant species, they are refuges of some characteristic plant species, which are absent or infrequent in neighbouring habitats. Moreover, the changes in physicochemical properties of the soil (higher average ammonium NH₄⁺-N and nitrate NO₃^--N content) and vegetation structure are very deep, as they have persisted for 25 years.

The purpose of this research has been to identify relationships between soil moisture and the growth and development of microorganisms, their diversity and the activity of soil enzymes. Four soils with different texture were analysed. Air-dry soils were watered up to the moisture content corresponding to 20, 40 and 60% of the maximum water capacity (MWC) and subsequently were submitted to determinations of the counts of soil microorganisms, colony development index and ecophysiological diversity index for bacteria, actinomycetes and fungi. In addition, the response of seven soil enzymes to soil humidity was examined. It was found that the most optimum soil moisture for the development of organotrophic bacteria was the one at the level of 20% of MWC. For Azotobacter spp. bacteria and actinomycetes, the 40% MWC soil moisture level was optimum, while fungi developed the best at the soil moisture level of 60% of MWC. In turn, the activity of soil dehydrogenases, catalase, urease, acid phosphatase, alkaline phosphatase, β-glucosidase and arylsulfatase was the highest in soil with 20% of MWC. The principal component analysis showed that the soil moisture determined the microbial and biochemical soil activity to a much lesser degree than did the soil type.

In field experiments over three vegetation periods (2010-2012) we studied impact of the CULTAN (controlled uptake long term ammonium nutrition) method on yield and yield parameters of kernel maize. The field experiments were conducted at three sites with different soil-climatic conditions. CULTAN treatments were fertilized once with the total amount of nitrogen using an injection machine (at the canopy height of 20 cm) and compared to conventional fertilization with calcium ammonium nitrate application at pre-sowing preparations. In all treatments the amount of nitrogen was the same, 140 kg N/ha. In 2010 at Humpolec site, CULTAN urea ammonium nitrate + inhibitor of nitrification treatment gave by 20.5% higher number of ears compared to CULTAN urea ammonium nitrate treatment. In 2011 at Ivanovice all CULTAN treatments reached statistically significantly higher number of kernels per ear. The higher 1000 kernel weight at CULTAN treatments was observed in 2012 at the Ivanovice site; a statistically significant difference between conventional and CULTAN urea ammonium nitrate + inhibitor of nitrification treatment was observed. Fertilization of maize with nitrogen using the CULTAN method under the conditions of the Czech Republic provides the same yield certainty as the conventional surface application and the CULTAN method of fertilization increases the yield certainty at delayed sowing. Harvest index was statistically significantly influenced by year, fertilization treatment and site.

The paper presents the impact of a historical system of terraces constructed centuries ago to mitigate the effect of a steep slope on overland flow. Systems of this type were constructed in past centuries by land owners, who then ploughed the land and grew crops on it. They used stones collected from the local agricultural fields as their terracing material. The influence of terraces on overland flow was simulated using the KINFIL. The overland flow is therefore reduced by greater infiltration of extreme rainfall excess flows on the terraces, and the KINFIL model shows to what extent the system of terraces can mitigate the resultant flood and soil erosion. The Knínice locality in North-Western Bohemia, with seven terraces and six field belts between them, was selected as the experimental catchment area. The results compare hydrographs with N-year recurrence of rainfall-runoff time, where N = 10, 20, 50, and 100 years, and the hydraulic variables, e.g. overland flow discharges of a design rainfall, hydraulic depths, flowing water velocity, and shear stress. The comparison provides hydraulic results with terraces and without terraces. The contrast between the results with and without terraces shows the positive role of the system of terraces in protecting the field belts.

Fertilization of crops with pig manure is a common practice throughout the world. Nevertheless, due to the relatively high copper (Cu) and zinc (Zn) contents in pig manure, continuous application of pig manure could have negative effects on soil and plant. The study aimed at the impacts of long-term applying different pig manure rates (equivalently 0, 100, 250 and 500 kg total N/ha/year from 2002 to 2008 and 0, 10, 25 and 50 t fresh weight/ha/year from 2009 to 2011, respectively) on Cu and Zn accumulation in soil and plant. During the 10 years of the experiment, a total of 2.04 to 10.20 kg/ha/year for Cu, 3.15 to 15.73 kg/ha/year for Zn were applied to the soil. Results from this study showed that long-term pig manure application resulted in serious accumulation of Cu and Zn in soil, total Cu and Zn concentrations increased by 204% and 107% at high application rates, respectively. Although topsoil Cu and Zn concentrations were below concentrations considered phytotoxic to crops, according to current Chinese legislation, it would take only less time than 16 and 27 years of high application rates to reach the allowable limits. Our result also suggested that Cu and Zn leaching occurred in the tested soil. The Cu and Zn concentrations in stalks and grains were not affected by the application of pig manure, and these values were lower than the threshold values for animal and human ingestion.

Bromus species are annual winter weeds from the Poaceae family which have become troublesome weeds of winter cereals. The herbicides propoxycarbazone and pyroxsulam are widely used for control of B. sterilis. The objective of this study was to determine the effect of different types of adjuvants and carriers on the efficacy of pyroxsulam and propoxycarbazone on B. sterilis. Small plot field trials were carried out in North Bohemia, Central Europe during 2011-2013. The tested carriers and adjuvants affected the efficacy of both herbicides and the seed production of B. sterilis. Urea ammonium nitrate was a less effective carrier than water (differences 5-30%). The most effective adjuvant was methylated seed oil (MSO), whose addition into the application water solution increased the herbicide efficacy of propoxycarbazone by 5-35%. Efficacy of the herbicide pyroxsulam was increased by adjuvant MSO by 10-30%. Nonionic surfactant increased herbicide efficacy only in 2013 (by 17%). Effect of organosilicone surfactant on the herbicide efficacy was negative (lower efficacy). Seed production of B. sterilis on untreated plots ranged between 20 000 and 50 000 seeds/m² in experimental years. Seed production was the lowest on plots treated by the herbicide plus MSO (1300-4500 seed/m²).

A long-term experiment was used to evaluate the effects of different nutrient management practices on the distribution of soil organic N fractions and their contribution to N nutrition of a rice-wheat system. Continuous rice-wheat cultivation for 13 years without any fertilization was unable to maintain total soil nitrogen level to its original level and resulted in a decrease at 8.3 mg N/kg/year. Likewise, amino acid N, amino sugar N, ammonia N, hydrolysable unknown N, total hydrolysable N and non-hydrolysable N decreased by 37.2, 29.6, 33.7, 10.4, 26.6 and 20.4%, respectively over their initial status. However, application of inorganic fertilizers alone or in combination with organic manures led to a marked increase in total N and its fractions. The increase in total N with the application of farmyard manure, press mud and green manure along with inorganic fertilizer over treatment with inorganic fertilizer alone was 23.1, 34.4 and 7.0%, respectively. These results imply that integrated use of inorganic fertilizers with organic manures represent a sound practice for sustaining N reserves in soil. On average, amino acid-N, amino sugar-N, ammonia-N and hydrolysable unknown-N constituted about 27.9, 10.7, 28.7 and 32.7% of the total hydrolysable-N, respectively.

The stem and bulb nematode (Ditylenchus dipsaci) is a serious quarantine pest of vegetables spreading worldwide via seed and planting material. Currently, a hot water technique is used as the pre-seed treatment, which is difficult to execute and the risk of seed damage is high. The objectives of this study were to evaluate the (a) penetration of gaseous hydrogen cyanide (HCN) into garlic tissue; (b) HCN phytotoxicity, and (c) nematicide potential of HCN against D. dipsaci. Penetration of HCN into the core of the garlic clove was approximately 30% of the concentration inside the fumigation chamber after 30 h of exposure. Decreased emergency was observed only in the exposure treatment lasting 16 and more hours. Garlic cloves naturally infested by D. dipsaci were treated with HCN at a concentration of 20 g/m³ for 12, 18 and 24 h in a fumigation chamber, and 99% mortality was achieved in all three exposure times.

Isotopic carbon discrimination (Δ¹³C) of winter wheat grain grown under different water and nitrogen supplies was determined. In two field experiments during years 2004-2007 (A) and 2008-2013 (B), a water shortage was induced from the flowering stage on with a mobile shelter (S), while an optimal water supply was ensured with drip irrigation (I), and a rain-fed crop served as the control treatment (R). Water supply had a statistically significant effect on grain Δ¹³C values in both experiments (P < 0.01). The average values of grain Δ¹³C in treatments I, R and S were 19.43, 18.68 and 17.70‰ (A); and 20.36, 19.60 and 18.13‰ (B). Grain Δ¹³C was in a significant linear relationship (P < 0.01) with the amount of water supplied by precipitation or irrigation. The regressions suggested that grain Δ¹³C increased by 1.14‰ and 1.16‰ (A), and 0.98‰ or 0.96‰ (B) for every 100 mm of water from January and March, respectively, until the early dough stage (r = 0.79-0.74, P < 0.05). Pooled data for the whole period 2004-2013 showed increases of 1.06‰ and 1.08‰ (r = 0.91 and 0.82, P < 0.05) for 100 mm of water, respectively. The results of the experiment confirmed the stable and predictable effect of water supply on wheat grain Δ¹³C.

The purpose of the study was to establish quantitative and qualitative composition of soil-borne microorganisms in the cultivation of carrot. The experiment considered rye, white mustard, buckwheat and sunflower as cover crops and three systems of cultivation. The population of bacteria and fungi having an antagonistic effect towards selected fungi pathogenic to carrot was determined. The greatest total population of bacteria as well as Bacillus spp. and Pseudomonas spp. was observed in the soil when rye was the cover crop. The greatest quantity of fungi was found in the control, a slightly smaller amount - after using sunflower, buckwheat and white mustard. The system of tillage had no effect on the communities of the investigated microorganisms. Rye and white mustard had the most positive effect on the quantity of antagonistic Bacillus spp., Pseudomonas spp., Clonostachys spp., Myrothecium spp., Penicillium spp. and Trichoderma spp. Regardless of the tillage system, the smallest quantity of antagonistic microorganisms occurred in the conventional cultivation of carrot.

The surface carbon dioxide (CO₂) fluxes together with the soil microbial biomass and activity in undisturbed soil columns were studied in three growing seasons. Soil columns had six treatments: (1) control without plants; (2) mineral fertilized without plants; (3) no fertilizer and maize plants; (4) mineral fertilized and maize plants; (5) manure and maize plants; (6) mineral fertilized plus manure and maize plants. Soil microbial biomass was measured by substrate-induced respiration (SIR) and microbial activity as fluorescein-diacetate hydrolysing activity (FDA). Treatments had a significant effect (P < 0.001) on CO₂ fluxes, SIR and FDA. The presence of maize increased CO₂ efflux, SIR and FDA compared to unplanted column. Fertilizer + manure treatment resulted in the greatest plant biomass and the greatest CO₂ efflux. Significant correlation (r = 0.680; r = 0.586 in two consecutive years) between SIR and FDA was found.

Paddy rice is important for Chinese agriculture and crop production, which largely depends on the leaf nitrogen (N) levels. The purpose of this study is to discuss the relationship between the fluorescence parameters and leaf N content of paddy rice and to test their performance in inversing N content of crops through back-propagation (B-P) neural network. In the correlative analysis of the fluorescence parameters and the N content, we found that the correlation between fluorescence ratios (F740/F685 and F685/F525 (F740, F685, F525 - intensity of fluorescence at 740, 685 and 525 nm, respectively)) and the N content (R² are 0.735 and 0.4342, respectively) is weaker than that between the intensity of fluorescence peaks (F685 and F740) and N content (R² are 0.9743 and 0.9686, respectively). Our studies show that the accuracy and precision of N content inversion which is acquired from the intensity of fluorescence peaks through the B-P neural network model are significantly improved (root mean square error (MSRE) = 0.1702, the residual changes between -0.1-0.1 mg/g) compared with the fluorescence ratio (MSRE = 0.3655, the residual changes from -0.3-0.3 mg/g). Results demonstrate that the intensity of fluorescence peaks can be as a characteristic parameter to estimate N content of crops leaf. The B-P neural network model will be serviceable approach in inversing N content of paddy leaf.

Humic acid urea fertilizer (HA-N) is a new type of slow-release nitrogenous fertilizer that can enhance utilization rate of urea, and consequently increases crop yield. However, there were few researches about the effect of HA-N on the nitrogen absorption and utilization in sweet potato production. Hence, the effect of HA-N on nitrogen accumulation and distribution, nitrogen use efficiency (NUE), and yield of sweet potato was studied in the field using the ¹⁵N tracer technique. Results showed that HA-N significantly increased the number of storage roots per plant and the average fresh weight per storage root, as well as the yield increased by 29.6% compared with urea fertilizer. Furthermore, nitrogen accumulation of total plant was higher under the HA-N. In addition, HA-N significantly increased nitrogen production efficiency of fertilizer and nitrogen production efficiency. Results of a ¹⁵N tracer experiment revealed that the percentage of nitrogen absorbed by plant from fertilizer increased from 31.1% to 38.7% and NUE increased from 33.5% to 44.8% with application of HA-N when compared with single N treatment, respectively. HA-N significantly increased sweet potato storage root yield, nitrogen absorption and NUE, as well as it reduced the loss of nitrogen fertilizer.

Balancing the use of maize (Zea mays L.) residues for soil amendment and forage is an important strategy for agricultural sustainability. Therefore, the study assessed the impacts of four proportions of maize residues to soil retention (S) and forage (F) on soil total organic carbon (TOC); total nitrogen (TN); carbon/nitrogen ratio (C/N); grain yield, economic benefits and nutritional contents of removed residues. The concentrations of TOC and TN increased when more residue returned, while the C/N ratios were S₁₀₀ + F₀ > S₃₄ + F₆₆ > S₆₆ + F₃₄. Also, crude protein, crude fat, and crude starch in the removed residues were F₃₄ > F₆₆ > F₁₀₀, while the crude fiber and ash contents exhibited the opposite trend. The crop yield improved with residue retention increased, but there were no differences on the economic benefits of the four residue-use systems. The S₃₄ + F₆₆ system maintained a TOC ranging from 11.51 to 13.37 g/kg, a TN from 1.12 to 1.16 g/kg, 92.93% of the annual yields of the S₁₀₀ + F₀ system, and 6.2 t/ha/year of forage. Therefore, the S₃₄ + F₆₆ system can balance the use of maize residues for soil amendments and forage to sustainably develop a household crop-livestock system.

Stable isotope ¹⁵N tracer technique was used in combination with artificial rainfall simulation to study the influence of interflow and surface-flow on nitrogen (N) migration loss of soil-plant systems on typical red soil sloping uplands. This study also investigated the utilization efficiency of fertilizer N during different peanut plant growth stages. The results indicated that soil N loss was predominantly via interflow and erosive sediment. Fertilizer N loss during the initial growth stage was mainly through surface runoff, while that occurred as interflow increased from less than 5% to around 16% during the middle and late growth stages. The loss of fertilizer N through surface runoff, erosive sediment and interflow accounted for over 18% of the total N application. The utilization rate of fertilizer N by peanut plants was around 45% through its life cycle, and that 70% of N absorbed by this plant derived from the soil. This highlighted the importance of adopting effective methods to reduce nutrient loss through interflow and surface-flow, the need to increase the utilization rate of fertilizers, and the importance to maintain soil fertility at a relatively high level.

Several sets of soil samples were chosen to demonstrate the applicability of the Mehlich 3 extractant for the determination of sulphur (S) in soils. Archived samples from 139 basal soil monitoring plots (BSMS) sampled in 1995 and 2013, samples from eleven long-term field trials sampled in 1981 and 2017, 1167 soil samples from the areas vulnerable to S losses and 720 samples from the non-vulnerable areas sampled in 2010 were chosen for the experiments. Mehlich 3 clearly showed a statistically highly significant decrease in the soil S content caused by reduction of SO₂ emissions in the long-term field experiments from 33 mg/kg in 1981 to 8 mg/kg in 2017 for the median of the untreated controls. Similar results were obtained for BSMS samples, where an average decrease from 26 mg/kg in 1995 to 17 mg/kg in 2013 was found. Mehlich 3 also showed that more than 52% of samples from the areas vulnerable to S losses were in a very low content category in contrast to only 3% of soils from the other areas. Mehlich 3 clearly proved the capacity to distinguish changes in the content of soil S in all studied cases.

The 28-day incubation experiment was carried out to evaluate the impact of the application of digestate (Dig); digestate with straw (DigSt); pig slurry (Slu) and mineral fertilizer (NPK) on Cd, Cu, Mn and Zn availability, on K₂SO₄-extractable carbon content and on the soil pH value in long-term contaminated soil. At days three and seven of the experiment, the 0.01 mol/L CaCl₂-extractable fractions of Cd, Zn and Mn significantly decreased under organic treatments (Dig, DigSt and Slu) with the most pronounced effect under Dig treatment. The NPK treatment caused the increase of risky element concentrations since day 21 of incubation which was accompanied with pH decrease. The contents of 0.5 mol/L K₂SO₄-extractable carbon were the highest at day 3 and 7 of incubation in organic treatments. The significant correlations between 0.5 mol/L K₂SO₄-extractable carbon and CaCl₂-extractable metal concentrations showed a close relationship between fresh organic matter added in organic fertilizers and risky element availability, suggesting that newly added labile organic matter can form temporary ligands with risky elements and release them later following its decomposition.

The effect of organic, mineral and combined organic and mineral fertilization of soils on the winter wheat yields and nutrient contents in soils was evaluated in long-term field experiments. Two sites with different soil characteristics were evaluated - Lukavec u Pacova (cambisol) and Ivanovice na Hané (degraded chernozem). The type of fertilization influenced wheat yields. Nutrient uptake by winter wheat was higher under nitrogen (N) fertilization, which resulted in a negative balance of phosphorus (P) and potassium (K) and to a decrease of nutrient contents in the more fertile soils at Ivanovice na Hané. Two soil tests (Mehlich 3 method and NH₄-acetate method) were used to determine P and K availability. The mineral nitrogen fertilization negatively and significantly affected NH₄-acetate extractable concentrations of nutrients in the soils and these were lower in comparison with concentrations of P and K determined by Mehlich 3 method. Relative availability of P in alkaline soils from Ivanovice treated with mineral N increased while the soil pH decreased.

In this study, a simulation experiment by farm warming with infrared ray radiator was carried out, and results showed that the broad bean (Vicia faba L.) growing days were shortened by increased temperature. The seedling, ramifying, budding, blooming, podding, and maturing stages were shortened by 1-4, 1-2, 1, 2-3, 1-2, and 2-4 days, respectively, and the whole growing period was shortened by 7-16 days when the temperature increased by 0.5-2.0°C. The broad bean yield increased by 10.1-16.6% when the temperature increased by 0.5-1.0°C, and significantly decreased by 38.1-90.1% when the temperature increased by 1.5-2.0°C. Increased temperature significantly improved the fat, carbohydrate, ash and energy contents.