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Chemical additives can reduce ammonia emissions from ammonium-containing fertilisers. We aimed to investigate the effect of an additive based on carboxylic acid derivatives on ammonia emissions from slurry. In a randomised multi-plot field trial, three slurry treatments with increasing amounts of the additive based on carboxylic acid derivates were tested in comparison to untreated slurry and mineral fertiliser. Ammonia emissions were measured with so-called passive samplers, a method already used in numerous studies. However, problems arose during the evaluation of the collected data, so we examined the methodology used in more detail. The results of the measurements were analysed with regard to their spatial distribution and temporal variation. The results show that the more additives were used, the less ammonia was emitted, up to an emission reduction of 48% at the highest additive application rate. However, the spatial distribution of ammonia emissions reveals a drift of ammonia and, thus, an interaction between the plots. Thus, even in unfertilised plots, ammonia emissions of up to 50% of the treatment with the highest emissions were determined. Furthermore, it was also proven that the different times at which the slurry was applied influenced the level of ammonia emissions. Due to the interaction between the plots and the temporal differences in the application of the slurry, measuring ammonia emissions with passive samplers in multi-plot field trials, as presented in this study, is not suitable to quantify differences between the ammonia emissions from different treatments. Based on these results, recommendations for the use of passive samplers to measure ammonia emissions in field trials are proposed.

Bromus sterilis L. (barren brome) is one of the most economically important noxious grass weeds in the winter cereal fields of Europe. Its ecological behaviour in this agro-climatic region should be assessed for effective weed control strategies. The present study was conducted to assess the dormancy and germination response of the B. sterilis population from the Czech Republic under thermal, light, and stress conditions. The dormancy loss experiment revealed that seeds exposed to the light regime showed a remarkably lower percentage of germination, and under alternating temperatures of 10/20 °C in dark conditions, rapid loss of primary dormancy was observed. This population was found to germinate across a wide temperature range of 5–35 °C, with the highest germination rate at 25 °C (T50 = 1.14 days in dark, 1.21 days in light) and the germination time increased with decreasing temperatures below 25 °C. Further, due to fitness advantage, herbicide-resistant (R) biotypes were found to be more stress-tolerant than susceptible (S) biotypes under salinity and drought conditions. In the highest stress conditions, the germination of S biotypes was negligible, while R biotypes can germinate under high stress, but germination decreased below 25 °C. The current findings may add value to effective weed control strategies using prediction models based on seed dormancy and germination values under different hydrothermal conditions.

In this study, Illumina MiSeq sequencing of 16S and ITS2 rRNA genes were used to determine the dynamic changes in bacterial and fungal communities and soil properties and enzyme activities in rhizosphere soil of ginseng under forest after 5, 10 and 15 years of cultivation and different growth stages. Results showed that the changes were particularly prominent in 10-year-old ginseng under forest, and the trends of organic carbon, alkaline hydrolysed nitrogen, and available potassium were extremely similar in different duration of the crop, especially in the middle stage of rapid root growth, when soil nutrient consumption was severe, and soil enzyme activities of rhizosphere were significantly reduced. The observed changes in soil properties and enzyme activities caused by the cultivation duration of the crop and growth stage could be explained by the variations in the microbiome. The microbial composition of 10-year-old ginseng under forest has undergone significant changes, at the genus level, both Acinetobacter bacteria and Kazachstania fungi exhibited a higher abundance; the abundance of Bacillota (Firmicutes), and Candidatus udaeobacter with significantly lower abundance. This study initially revealed the changes in nutrient utilisation of ginseng under forest at different cultivation duration of the crop and different growth stages, as well as the regulatory role played by microbes in this process preliminarily. We consider 10 years to be a critical stage for the long-term cultivation of ginseng in the forest, during which it is more sensitive to environmental factors and may exhibit special dynamic changes affecting its growth and quality. This provides a reference for further precision planting and harvesting of ginseng under the forest.

The ecological and human health risks of heavy metal(loid)s (HMs) in soils around tungsten (W) mining sites have often disregarded the presence of W. In this study, we aimed to investigate the concentrations of 10 HMs (including W and other accompanying elements) in 18 agricultural soil samples obtained around a W mining site in southern Jiangxi, China. Furthermore, we determined the contamination status, source identification, and ecological and health risks of HMs in soils. Our findings revealed that HMs were extensively accumulated in soils within the study area, with the highest mean concentrations of W found. W concentrations were above background values at all sites. Multivariate analysis revealed that W mining activities, including extracting and transporting W ore, were the primary source of HMs in the soil (61.40%). The ecological risk assessment revealed that the potential ecological risk across the survey area exhibited a high risk, and the cadmium (Cd) and W should be prioritised as control pollutants for soils around the W mine site. The human health risk assessment displayed that 73.43% of children with an unacceptable non-carcinogenic risk, and W contributed the most to the overall non-carcinogenic risk (42.32%), followed by Cd and arsenic (As). In addition, 22.03% of children and 13.4% of adults were under a significant carcinogenic risk. Overall, our findings emphasise the importance of considering element W in future studies investigating the contamination of HMs around W mining areas. As such, we calculated a safe limit value for element W in soil (141.01 mg/kg) to facilitate the conservation and development of soils in W mining areas in China. Our study provides valuable information for pollution prevention and soil contamination risk mitigation in W mining areas.

A pot experiment was carried out to determine the effect of Serendipita indica on the salt response of Lolium multiflorum Lam. Although the salinity decreased the root colonisation of S. indica by 28.34%, successful colonisation of S. indica increased the seed germination rate, fresh weight, leaf relative water content and chlorophyll content by 28.09, 59.01, 38.78 and 28.80%, respectively, compared with uncolonised seedlings. Under salinity, leaf malondialdehyde content, leaf relative electrical conductivity, as well as Na+ content and Na⁺/K⁺ ratio in leaves and roots of S. indica-colonised seedlings were decreased by 33.99, 33.31, 63.40% and 47.42, 85.66 and 55.88%, respectively, compared with uncolonised seedlings. Meanwhile, compared with uncolonised seedlings under salinity, the contents of proline in leaves, N, P and K⁺ in leaves and roots of the S. indica-colonised seedlings were increased by 47.47, 45.69 and 30.05%, and 41.77, 19.51, 19.18 and 155.00%, respectively. These results indicate that S. indica colonisation confers salt tolerance in L. multiflorum seedlings by enhancing osmotic adjustment via actively accumulating proline and K⁺, increasing the uptake of nutrients such as N and P, and improving Na⁺/K⁺ homoeostasis. The study would provide a new idea for the combined application of salt-tolerant plants and symbiotic microorganisms in the ecological restoration of saline-alkali lands.

The effects of biogas residue as a substrate on ginseng growth and its feasibility for ginseng cultivation are unclear. The present study used biogas residue at different concentrations and maturity levels to cultivate ginseng. The biological characteristics of ginseng, soil physiochemical indices, and ginseng and soil microbial communities were investigated. The results showed that with increasing ginseng content and maturity, the total fresh weight, total length and saponin content significantly increased. The enzyme activities of soil, NO₃^–-N, and available phosphorus also increased. The microbiome analysis revealed that with the addition of biogas residue, microorganisms related to plant growth promotion, such as Chloroflexi, Gemmatimonadota and Mortierellomycota, were more common in the plant or rhizosphere soil. The results based on the co-occurrence network showed that the structure of the bacterial community was more stable than that of the fungal community with increasing biogas residue content. Our results indicated that biogas residue could be used as a ginseng cultivation substrate and promote growth.

Copper contamination stemming from copper-based pesticides poses a grave concern in vineyards and orchards, causing toxicity to soil organisms. Here, we present a comprehensive review of global data encompassing copper levels in these soils, coupled with variables such as the age of agricultural establishments, climate, soil organic matter content, soil pH, and farming practices (organic vs. conventional). The results suggest that there are three pivotal determinants driving copper content in vineyard and orchard soils: climate, the age of agricultural establishments, and soil organic matter content. It was impossible to estimate soil pH’s effect on soil copper content because of its dependence on precipitation. Copper content in vineyard and orchard soils worldwide follows a direct correlation with precipitation while inversely correlating with aridity (i.e. potential evapotranspiration divided by precipitation). Furthermore, a clear linkage emerges between farm age and increased copper content in soils globally. Intriguingly, the increased soil organic matter content has shown inverse impacts on soil copper levels. These effects of soil properties on soil copper contents were discussed in terms of copper losses from soil via surface runoff. However, no discernible disparities in soil copper content between organic and conventional farming systems were found. This worldwide survey not only underscores the established influence of climate on European vineyards but also sheds novel light on the historical legacy of copper contamination in these landscapes.

The presented research deals with the effect of plot size changes on the crop yield. Three plots were chosen in a company engaged in conventional agriculture, on which yields were monitored from 2019 using yield maps. In 2020, the plots (initial size > 30 ha) were divided into different parts sized < 30 ha. In 2021, these newly arisen parts of the plots were harvested. Changes in the yield of grown crops were analysed using yield maps acquired by the harvesting machines. Relative yields (%) and absolute yields (t/ha) were determined on all experimental land parts arising from the initial plots’ division. The values were then compared with yields recorded before the division of individual plots using zonal statistics. Measured relative yield values clearly show (P < 0.05) that the division of plots resulted in the increased heterogeneity of crop yields. On the initial plots as well as on the newly arisen plots, the relative yield was divided into the following categories: < 70, 70–85, 85–95, 95–105, 105–115, 115–130 and > 130%, with the value of 100% representing average yield. The analysis of measured yield data showed that the division of plots into smaller parts resulted in an uneven yield distribution because if a divided plot was heterogeneous in terms of yield levels, a cumulation of "higher yield levels (> 100%)" could have occurred in one specific newly arisen plot at the expense of another one. Moreover, new marginal parts of lands came into being during the division of larger soil complexes, and hence zones with potentially reduced yields.

To address the issue of low soil nutrients and low crop yields in coastal alkaline salines, a field experiment of straw combined with plastic film mulching in coastal alkaline salines was conducted in this study to explore the effects of different treatments on soil nutrients, enzyme activities and maize yield. Four treatments, including no mulching (NM), straw mulching (SM), plastic film mulching (PM), and straw mulching combined with plastic film mulching (SP), were set up during 2019–2020. In the 0–20 cm soil layer, compared with NM, the soil organic carbon (SOC) and soil catalase activity (SCA) of SM significantly increased by 23.4% and 46.2%, respectively (P < 0.05). The soil total nitrogen (STN), soil available phosphorus (SAP), available potassium (SAK), sucrase activity, urease activity, alkaline phosphatase activity, and maize yield (MY) of SP significantly increased by 40.7, 26.8, 13.9, 34.6, 73.8, 36.2 and 19.0%, respectively (P < 0.05). SOC, STN, SAP, SAK and SCA were significantly correlated with MY. Therefore, straw mulching combined with plastic film mulching has the best effect on increasing soil nutrients, soil enzyme activity, and maize yield and is suitable for promotion and application in coastal alkaline salines.

Three-year field trials were conducted to compare the effect of three tillage systems: strip-tillage (ST), strip-tillage after mouldboard ploughing (STmp) and conventional tillage (CT) on growth and yield of winter oilseed rape at the experimental station in Červený Újezd, Czech Republic. Compared to CT, the growth of roots and aboveground biomass was slower (significantly thinner root necks, shorter roots and leaves) under ST at the beginning of vegetation (BBCH 14-18). Plants under ST still had significantly thinner root necks, and a lower number of leaves than plants from CT before winter (BBCH 21) but the differences were no longer statistically significant in spring (BBCH 30). Despite a slower start, the ST variant with an average yield of 5.47 t/ha significantly exceeded the CT variant with the yield being 5.06 t/ha. Conversely, plants grown under STmp had significantly longer leaves than those under CT in BBCH 14-18 and with the highest values of all parameters, tended to faster growth of biomass, although the other differences were not statistically significant. No differences were observed between STmp and CT in BBCH 21 and 30. The STmp variant achieved the highest yield 5.53 t/ha, and significantly exceeded the CT variant.

Drought stress is one of the major limiting factors to crop productivity around the globe. It has been well documented that spermidine (Spd) plays an important key role in plant growth and development, especially in the defense response to stress. The objective of this study was to explore the effect of Spd on protecting photosynthetic apparatus in tall fescue under drought stress. Spd application significantly improved the OJIP (fluorescence rise kinetics O-J-I-P) curve compared to non-Spd application during drought. Exogenous Spd exhibited higher F_J (fluorescence value at the J-step (2 ms) of OJIP) and F_P (maximal recorded fluorescence intensity, at the peak P of OJIP) than non-Spd application. Moreover, normalised total complementary area (S_m) and the number of Q_A (primary quinone acceptor of PS II) reduction events (N) significantly reduced after the application of Spd in tall fescue under drought stress. In terms of quantum yields and efficiencies and specific energy fluxes, exogenous Spd notably decreased the values of efficiency of electron transfer from Q_B (secondary quinone acceptor of PS II) to PSI acceptors (δR₀), absorption flux per RC (ABS/RC) and trapping flux per RC (TR₀/RC) compared to the non-Spd application without watering. All the above suggested that exogenous Spd facilitated the photosynthetic system of tall fescue in drought. These observations involved in the electron transport capacity of photosystem II assist in understanding better the protective role of exogenous Spd in tall fescue under drought stress.

The use of cannabis for medicinal purposes dates back well before the era of modern medicine, but in recent years research into the use of medical cannabis in the medical and pharmaceutical sciences has grown significantly. In European countries, most cannabis plants have been and still are grown for industrial purposes. For this reason, hemp cultivation technology is relatively well researched, while little is known about the key factors affecting cannabis cultivation for medical purposes. The active substances of cannabis plant targeted by this review are called phytocannabinoids. The biosynthesis of phytocannabinoids is relatively well understood, but the specific environmental factors that influence the type and number of phytocannabinoids have been much less studied. Indoor or greenhouse cultivation, which uses automated lighting, ventilation, irrigation systems and complex plant nutrition has become much more sophisticated and appears to be the most effective method for producing medical cannabis. There are many different cultivation systems for cannabis plants, but one of the essential elements of the process is an optimal plant nutrition and selection of fertilisers to achieve it. This review summarises the existing knowledge about phytocannabinoid biosynthesis and the conditions suitable for growing plants as sources of medical cannabis. This review also attempts to delineate how nutrient type and bioavailability influences the synthesis and accumulation of specific phytocannabinoids based on contemporary knowledge of the topic.

The focus of this study is on the soil physicochemical, biological, and microbiological processes altered by biochar application to heavy metal (HM) contaminated soils. The aim is to highlight agronomical and environmental issues by which the restorative capacity of biochar might be developed. Literature shows biochar can induce soil remediation, however, it is unclear how soil processes are linked mechanistically to biochar production and if these processes can be manipulated to enhance soil remediation. The literature often fails to contribute to an improved understanding of the mechanisms by which biochar alters soil function. It is clear that factors such as biochar feedstock, pyrolysis conditions, application rate, and soil type are determinants in biochar soil functionality. These factors are developed to enhance our insight into production routes and the benefits of biochar in HM soil remediation. Despite a large number of studies of biochar in soils, there is little understanding of long-term effects, this is particularly true with respect to the use and need for reapplication in soil remediation.

The aim of the study was to assess soybean response to sowing material inoculation with HiStick® Soy preparation, containing Bradyrhizobium japonicum. Based on the obtained results, it was found that the inoculation significantly increased the number and dry weight of nodules on soybean roots compared to control. The bacterial preparation significantly increased the number of pods per plant. As a result, a significant increase in seed yield (0.58 t/ha) was obtained compared to control. HiStick® Soy increased total protein content in seeds. Protein and fat yield was higher after seed inoculation by 318 kg/ha and 101 kg/ha, respectively, compared to control.

The article presents the effect of three sowing dates on the growth, development and yielding of four soybean cultivars of different earliness and under different temperature and precipitation conditions across the years. The seed yield from early sowing significantly correlated with the total precipitation in June and July, and at later dates, also with the total precipitation in August. The significantly highest soybean yields were collected from the sowing at a turn of April and May, and the highest seed and protein yield, as well as protein content in seed, were recorded for the mid-early Merlin cultivar. Neither the number and the seed weight per pod nor the 1 000-seed weight significantly depended on the sowing date. Over years, a significant, almost linear decrease in the plant height and the first pod setting height, the weight of nodules, the protein yield and the LAI (leaf area index) value was observed. High significant correlations were found between the seed yield and the plant height and the first pod setting height, as well as between the seed number and the seed weight per pod and the 1 000-seed weight as well as between the plant height and the first pod setting height.

This study was carried out to present an innovative solution for interpreting large data sets in agri-statistics with the invocation of programmed visualisation. Moreover, the following polyfactorial long-term experiment embodies a comprehensive study of 18 wheat quality parameters. The effect of increasing dosages of fertiliser (control, N₉₀PK, N₁₅₀PK) was examined on 3 winter wheat cultivars (KG Kunhalom, GK Csillag, Hybiza) in two consecutive growing seasons (2018-2019). The ecological conditions of 2018 gave a significantly higher yield, meanwhile 2019 significantly augmented gluten spread, alveographic tenacity, alveographic deformation work, valorigraphic stability and quality group and loaf volume. N₉₀PK dosage was enough to realise yield and quality potential as well. Fertilising significantly improved 13 indices, namely yield, crude protein, Zeleny index, wet gluten content, alveographic extensibility, alveographic deformation work, valorigraphic water absorption, quality number and group, dough development time, stability, softening and loaf volume. Considering yield, cv. Hybiza performed better, while cvs. KG Kunhalom and GK Csillag possessed significantly better protein-linked postharvest attributes. One of the most important findings is that waffle chart, joint plot, correlation matrix and complexradar of Python provide a very powerful tool in agri-statistics. Also, the results can potentially improve the knowledge about cultivar-specific agronomy practice, wheat quality and the connections between these parameters.

High temperature decreases winter wheat grain yield by reducing the grain number and grain weight. The effect of heat stress on spike grain distribution and weight of individual grains within spike and spikelets was less studied. Our aim is to identify influence of high temperatures during different phenological stages on spike grain distribution and weight and to explore genotypic variation of the studied wheat cultivars. Within this study, a controlled experiment was conducted with 12 different winter wheat cultivars under heat stress at anthesis and mid-grain filling stage. The results showed that spike grain weight, thousand-grain weight and grain number per spike decreased moderately in treatments with individual heat stress at anthesis and mid-grain filling period, respectively, which decreased severely in the multiple heat stressed plants at both stages compared with the control treatment. Heat stress decreased number of spikelets with grains. Grain weight at the G1, G2 and G3 positions had a positive relationship with spike grain weight. Among the studied Serbian wheat cultivars Subotičanka and Renesansa were identified as the most heat tolerant and sensitive, respectively. Heat tolerance of the studied cultivars should be based on the cultivar capacity to retain higher grain weight, and to maintain production of distal spikelet grains.

The objectives of this study were to investigate the nitrogen (N) and phosphorus (P) balance fertilization strategy in paddy fields, and to evaluate the effects on N uptake and utilization in rice. In 2017-2018, the experiment was conducted using Deyou4727 hybrid rice with four different P fertilizer levels (0, 30, 60, and 90 kg/ha), marked as P0, P1, P2, P3 in turn, and four different N levels (0, 90, 150, and 270 kg/ha), similarly marked as N0, N1, N2, N3 in turn. The results showed that in the N-insufficient (N0, N1) environments, the P1 treatment increased N uptake and promoted transfer to the grain. However, high-P (P3) application increased the dry matter accumulation than other P levels, but limited the production and translocation of dry matter to some extent. In N-sufficient (N2, N3) environments, P2 level increased crop yield and N use efficiency by 11.35% and 37.01%. Unlike P2, none-P (P0) and high-P levels decreased rice dry matter translocation and transport capacity, which further affected N uptake and utilization in N-sufficient environments. Overall, the combination of the N application rate of 90 kg/ha and P application rate of 30 kg/ha, N application rate of 150, 270 kg/ha, and P application rate of 60 kg/ha had a high yield; strong nutrient accumulation and transfer ability. It was more inclined to balance N and P, which was beneficial to plant N absorption and utilization.

Plant-based indicators of water status, such as midday stem water potential (Ψ_stem) and leaf stomatal conductance (g_s), are used to optimise irrigation scheduling in horticultural crops because they integrate the effect of soil and climatic conditions and the internal physiological constraints. The use of these indicators relies on experimentally acquired thresholds that relate the value of the indicator to negative effects on yield. In five irrigation treatments, we monitored yield, fruit size and the courses of Ψ_stem and g_s throughout four consecutive growing seasons. We found that Ψ_stem was more sensitive to irrigation treatment than g_s. Both indicators increased with available soil water content (ASWC) and decreased with evaporative demands of the atmosphere (ET_C). On a seasonal basis, crop load had a stronger impact on g_s than Ψ_stem. In summary, our study explored the effect of environmental conditions and crop load on plant-based indicators of tree water status and can be useful for establishing thresholds for irrigation scheduling in apple tree orchards.

Phosphorus (P) deficiency significantly affects crop productivity, especially legume crops. Therefore, it is important to understand the P-acquisition strategies of different leguminous crops. In this study, we undertook a pot experiment with 11 legume crops (soybean, faba bean, pea, cowpea, common bean, lentil, adzuki bean, chickpea, grass pea, red kidney bean and common vetch) to investigate P-acquisition strategies related to root morphology, organic acid and acid phosphatase exudations, and arbuscular mycorrhizal fungi (AMF) colonisation under low (4.4 mg/kg) and optimal (40 mg/kg) P conditions. The results revealed that P deficiency significantly decreased biomass and P accumulation, root length (10.5%), and root surface area (7.9%), increased organic acid exudation (80.2%) and acid phosphatase activity (16.8%), and did not affect root diameter or root AMF colonisation rate. Principal component analysis revealed a positive correlation between organic acid exudation and acid phosphatase activity, while root length and root surface area negatively correlated with organic acid exudation, acid phosphatase activity and root AMF colonisation rate. P accumulation positively correlated with root length, surface area, and diameter but negatively correlated with organic acid exudation, acid phosphatase activity, and AMF colonisation rate. These findings confirmed the following: (1) legume crops use a P-mobilisation strategy related to organic acid exudation and acid phosphatase activity to acquire P under low soil P conditions; (2) organic acid exudation coincided with acid phosphatase activity to mobilise soil inorganic and organic P, improving P accumulation; (3) a trade-off exists between the P-scavenging strategy related to root morphology traits and mobilisation strategy.

The improvement of rice production to meet food needs for the increasing population is a general problem faced in wetland development for agriculture. The use of industrial waste, such as coal fly ash (CFA), could effectively improve the soil properties of wetlands. In this study, CFA with an amount of 2% (weight/volume) or 240 g was added to 12 L of three different soils collected from the rice fields (peatland, swampland, and rainfed field) in a 15-L pot, and then incubated in the greenhouse for 15 days. The soil pH, concentrations of NH₄⁺-N, NO₃^–-N, exchangeable calcium (Ca) and magnesium (Mg) and available phosphorus in the soil were quantified following the completion of the incubation. Rice seedlings were planted in each pot, and after 90 days, the growth and yield variables were observed. The results showed that CFA application enhanced the concentrations of NH₄⁺-N, NO₃^–-N, and available phosphorus in peatland and swampland, the rice fields that contain high organic carbon (C), which ultimately leads to increasing rice growth and yield. The application of CFA to rice fields containing low organic carbon did not improve available nitrogen and phosphorus nor enhance the growth and yield of rice. Results of this study indicate an important role of soil organic C content in the rice fields in controlling the effect of CFA on nutrient availability, growth and yield of rice.

This study aims to verify the application effect of Fluvic acid (FA) with different molecular weights (MW) on the growth and quality of winter wheat. FA extracted from lignite was divided into 3 MWs (W1≤3000 D, 3000 D<W2≤10000 D, and W3>10000 D) by dialysis, and its structure was analyzed. Three application rates were set for each MW FA in the pot experiment, which were 10, 25 and 50 mg/kg in soil, respectively, and water was the control. There were significant interactive effects of MW and application rates of FAs. Compared with the control, all the FA treatments significantly increased grain yields, nitrogen uptake efficiencies, grain iron concentration, and soil available nitrogen concentration. Heatmap analysis revealed that the W1C2 (10 mg/kg W1) treatment had the most significant impacts for all analyzed indexes, whereas W3C3 (50 mg/kg W3) showed the weakest impacts. The results showed that at a low application rate (10 mg/kg in soil), the promotion effects of the three MW FAs were similar. W1 showed the most significant promotion effects, which was attributed to the combined effects of its lower MW and functional group characteristics.

Nitrogen dynamics in soil produce N2O emissions. To decrease N2O emissions and conserve N, recent studies have focused on chemicals derived from root exudates that inhibit nitrification. However, selective plant breeding could be used to control nitrification activity in soil instead of fertilisers or synthetic nitrification inhibitors. In this study, we investigated the relationship between nitrification rates (NR) and related N dynamics and plant characteristics for 11 maize varieties with varying levels of nitrification inhibition (NI) compared to Brachicaria humidicola (Bh) as the positive control. In a greenhouse experiment, soil concentrations of NI, NR, NH4+-N, and NO3--N and nitrogen uptake by plants were measured. Six maize varieties had a 1.1–1.6 times lower NR than Bh. Low-NR varieties had higher NI and lower root-to-shoot ratios. NI was positively correlated with total N and shoot N content but not with cumulative N2O and NH4+-NO3-. These results show that maize has the capacity to reduce soil nitrification while increasing the total N in the soil and shoot N content in maize.

One of the latest environmentally friendly methods in soybean production technology is the pulsed electromagnetic field of low frequencies (PEMP). The paper presents the results of the influence of electromagnetic stimulation of soybean seeds on grain yield, protein and oil yield, depending on different agroclimatic conditions, exposure time and frequency. In the 2012–2017 research period, the soybean cv. Valjevka was used in the Institute of Field and Vegetable Agriculture experimental field, Novi Sad, Serbia. Immediately before sowing, the seeds were subjected to PEMP treatment, with a pulse generator and a tape applicator, in the following variants: electromagnetic field frequencies of 16, 24 and 30 Hz, and exposure time of 0, 30 and 60 min. The most successful variant of seed stimulation for all three examined parameters was at 16 Hz and 30 min, where the research results show that this measure can increase the examined parameters by more than 10%. The average yield of grain for all years of research with seed stimulation was 4.85% (3 338 kg/ha) compared to the control (3 203 kg/ha). The average grain protein yield in the treatments with PEMP was 1 315 kg/ha, which was 4.26% higher compared to the variant without PEMP (1 260 kg/ha), and the treatment was 4% higher in the average oil yield, 703 kg/ha compared to the control 676 kg/ha. Also, the analysis of the mutual dependence of the indicators is in a positive correlation, which is essential for plant breeding and the development of new technologies, which have economic justification, are safe for use and have a positive impact on adverse effects such as drought.

Maintaining nitrogen (N) balance and inhibiting N leaching loss in the soil-crop system is crucial to maintaining yield and reducing the environmental pollution. This study investigated the effects of soil NO₃^--N content and accumulation, eggplant yield, N leaching and balance response to biochar addition, including regular fertilisation and irrigation (W + F), biochar addition with regular fertilisation and irrigation (W + F + B), and biochar addition with 20% fertilisation and irrigation reduction (0.8W + 0.8F + B) treatments. Compared with W + F, W + F + B and 0.8W + 0.8F + B increased soil NO₃^--N content in 0-40 cm and soil NO₃^--N accumulation in 0-20 cm, and raised harvest index, N surplus and balance. Simultaneously, 0.8W + 0.8F + B compared to W + F enhanced N use efficiency and N partial factor productivity, conversely, it decreased N dry matter production efficiency, N surplus and balance. Stepwise regression analysis demonstrated that the effect of NO₃^--N leaching lasted in 60 cm under biochar addition in the first year, and lasted in 20 cm without biochar application in the next year. Altogether, biochar addition with 20% fertilisation and irrigation reduction is the most suitable management strategy to decrease N surplus and leaching, and maintain eggplant N uptake in a two-year cycle system on greenhouse vegetables in Mollisols.

The effects of potato drip irrigation on soil nitrogen dynamics and potato yield was studied in small-plot field trials. The trials were evaluated at during three experimental times seasons (2016-2018). Four variants of irrigation were determined, ie non-irrigated, 60, 65 and 70 ASWC (Available Soil Water Capacity). At the same time, two pre-planting fertilization dates were set at a maximum of 120 kg N/ha a in divided i.e. 60 kg N/ha before planting and 60 kg N/ha by fertigation during vegetation. Pre-planting crop fertilization or in-season fertigation did not have any significant effect on the potato yields of most variants. In all studied parameters, the positive beneficial effect of irrigation was recorded and compared to the non-irrigated control. The mitigation of drought stress in plants during the growing season is the most important advantage of irrigation. In the trials, on average across all years and varieties, the yield of the irrigated variant increased by 41 % compared to the non-irrigated variant. Maintaining optimal soil moisture has a favourable effect use of applied fertilizers. The highest mineral nitrogen content in the soil was recorded for the variant without irrigation. Considering the increased use of nitrogen fertilizers, the subsurface drip line appeared to be optimal for the creation of suitable conditions for nitrogen availability to plants in the root zone.

In this study, we addressed the reuse of two organic waste products as fertilisers. To this end, soil fertilised with the spent mushroom substrate (SMS) or with an anaerobic digestate (DIG) was subjected to an incubation assay, and the results were compared with those from soil treated with a mineral fertiliser (MIN) and an unfertilised soil (CO). The soil was sampled after fertilisation and after 90 days of aerobic incubation. Nitrogen (N) mineralisation (NH4+ and NO3–) and oxidable carbon (OC) were determined. The impact of the treatments on the soil was evaluated by measuring the enzymatic activity of arylsulfatase (ARYL), ß-galactosidase (GAL), and urease (URE). The highest OC content was observed in the SMS treatment. After 90 days of incubation, the SMS treatment showed a lower mineral N content than the CO treatment. This finding was associated with N immobilisation. However, mineral N significantly increased ARYL activity in the DIG and MIN treatments, and URE activity was always higher at both sampling times in the SMS treatment. Initially, GAL activity was notably high in the DIG treatment but decreased after incubation, reaching similar values to those registered in the CO treatment. Organic fertilisation treatments induced different effects on soil N mineralisation, showing changes in the activity of the enzymes analysed.

This study aimed to determine the effect of tea planting age on stoichiometric ratios of microbial biomass carbon (MBC), nitrogen (MBN), and phosphorus (MBP) and soil microbial quotient (SMQ, expressed as qMBC, qMBN, and qMBP, respectively). A chronological sequence of tea plantations (3, 8, 17, 25, and 34 years) was selected in a small watershed in the Three Gorges Reservoir Area, and a slope farmland was selected as control. The results showed that with the increase of tea plantation age, soil and microbial biomass C, N, P contents, soil C : N and C : P elevated significantly, while soil N : P overall declined; the MBC : P and MBN : P increased first and then decreased, but MBC : N varied insignificantly. The tea plantation age affected SMQ notably. qMBC first decreased and then increased following the tea planting age, while qMBN and qMBP went up in a fluctuating pattern. In this study, qMBC positively correlated with soil N : P and microbial biomass C : N : P, but negatively correlated with soil C : N and C : P; on the contrary, qMBN and qMBP negatively correlated with soil N : P and microbial biomass C : N : P, but positively correlated with soil C : N and C : P. Generally, the variations of soil microbial biomass and SMQ could reflect the soil quality of tea plantations.

Drought is an important agricultural problem worldwide, which seriously affects the growth and yield of crops. To explore the effects of different degrees of drought on the soluble sugar content of soybeans, this study measured the soluble sugar content of two soybean cultivars at three growth stages under four levels of drought stress. The results showed that drought stress significantly affected the soluble sugar content, and there were differences among different growth stages and cultivars. At the seedling and flowering stages, the sucrose content of both Heinong44 and Heinong65 showed an unimodal trend and reached the maximum value at moderate drought. The increase rate was the highest in the leaves at the flowering stage, which increased by 36.18% and 25.79% compared with CK, respectively. The fructose and glucose contents were the highest during severe drought, and the fructose content increased the most in the leaves at the seedling stage, which increased by 18.05% and 17.67% compared with CK, respectively. The glucose content increased the most in the petioles at the flowering stage, reaching 40.66% and 35.24%. At the pod-filling stage, the three sugar contents of both Heinong44 and Heinong65 were the lowest at severe drought, and the sucrose and fructose contents decreased the most in the petioles, which decreased by 21.66% and 23.94%, 12.58% and 13.49% compared with CK, respectively. The glucose content decreased the most in the stems, which decreased by 11.72% and 9.66%. In addition, at each growth stage and drought treatment, the ratio of the soluble sugar content of Heinong44 was higher than that of Heinong65.

If appropriately applied, tillage can positively affect the crop’s yield by enhancing the soil’s physical properties. Fertilisation also has beneficial effects on yield if applied at efficient rates by increasing available-to-uptake nutrients and improving soil’s chemical properties. A field experiment was carried out in Debrecen, Hungary, to evaluate the individual and the interaction effects of these 2 factors on sunflower and sweet corn. The cultivation methods applied were ploughing (C1), direct drilling (C2) and deep loosening (C3). In addition, 3 fertilisation rates were applied to each cultivation system: F1 (control, no fertilisation); F2 (100 : 50 : 70) kg NPK/ha and F3 (150 : 100 : 120) kg NPK/ha in a randomised complete block design (RCBD) with 4 replicates. Our results showed that fertilisation did not affect the yield of sweet corn measurably. However, C1 resulted in the highest yield, whereas C2 and C3 resulted in relatively similar yields. In sunflowers, the yields of both C1 and C2 were higher than that of C3. No significant differences were recorded between C1 and C2. The yields of both F2 and F3 were higher than the yield of F1. The differences between F2 and F3 were insignificant. It could be concluded that the cultivation method is a determining factor in the yield of sweet corn. The effects of both fertilisation and cultivation treatments were more detectable in sunflowers. The differences between the two fertilisation rates (F2 and F3) were insignificant in both species, indicating that the extra fertilisation levels might be unnecessary.