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Based on strip-tillage technology, this study explores the optimal seedbed environment for maize growth through a three-year field agronomic experiment. A comparative analysis of two planting modes, flat planting and ridge planting, was conducted, and a two-factor, three-level experimental design was implemented (furrow-breaking width: 8, 10 and 12 cm; furrow-breaking depth: 2, 3 and 4 cm), with manual soil covering without furrow breaking as the control group. Analysis of the averaged data over three years indicates that furrow-breaking treatment significantly increased maize yield under both flat and ridge planting modes, highlighting the importance of furrow breaking for maize growth. Ridge planting increased yield by an average of 7.58% compared to flat planting. The optimal yield was achieved at a furrow-breaking width of 10 cm and a depth of 4 cm, where ridge and flat planting yields were 10.37% and 10.43% higher than the average values at each level, respectively. Additionally, at the optimal yield level, the chlorophyll soil-plant analysis development (SPAD) values for ridge and flat planting were 15.36% and 17.06% higher than the average values. The emergence rates of ridge and flat planting maize were 5.43% and 4.93% higher than the average values, respectively. This not only enhanced crop stress resistance but also improved overall economic benefits.

Heavy metal stress inhibits plant growth, but this impact is less studied and pronounced under climate change conditions. The present study investigates the physiological, biochemical, and agronomic responses of wheat (C3) and maize (C4) exposed to varying thallium (Tl) stress (60 and 120 mg/kg) under ambient (aCO₂) and elevated (eCO₂, 710 µmol/mol) CO₂ levels. High Tl exposure markedly reduced grain yield by 58% in wheat and 68% in maize at 120 mg/kg under aCO₂. However, eCO₂ partially offset the negative effects, increasing yield by ~20% in wheat and 36% in maize at 60 mg/kg Tl. eCO₂ enhanced photosynthetic activity under eCO₂, which increased the accumulation of soluble sugars under TI stress. These provide carbon skeletons for the synthesis of primary metabolites such as amino acids, organic acids and fatty acids. Although total fatty acid content declined under stress, the metabolic crosstalk initiated by improved photosynthesis and sugar availability enables plants to maintain key fatty acids (such as palmitic, linolenic, and oleic acids) essential for membrane stability and function. Amino acids, especially proline and cysteine, accumulated significantly under Tl stress. These primary metabolites, in turn, feed into secondary metabolic pathways, promoting the formation of phenolic acids and flavonoids that enhance antioxidant defence and stress tolerance. This metabolic cascade explains eCO₂’s capacity to alleviate TI stress and improve crop performance, and underscores the value of leveraging eCO₂ environments to support agricultural productivity and food security under challenging conditions.

Crop production faces increased climate change and land degradation stresses, compromising global food security with the growing population. Maize (Zea mays L.) is a versatile crop used for food, feed, and raw materials, contributing significantly to global food systems. Abiotic stresses like drought and soil fertility limit its production. Fertilisation is an amelioration technique that optimises maize growth and yield by maintaining optimum nutrition and leveraging nutrient deficiency conditions. Precision agricultural tools like chlorophyll meters are essential for non-destructive chlorophyll assessment and nitrogen status. An experiment conducted at the University of Debrecen evaluated the impact of nitrogen (N) fertilisation (0, 90, and 150 kg/ha) and three maize cultivars (P9610-FAO 340, DKC4590-FAO360, and GKT376-FAO360) on physiological parameters, namely: relative chlorophyll content (SPAD), normalised differences vegetation index (NDVI) and grain quality. Results showed that SPAD and NDVI positively correlated (P < 0.05) with grain quality and yield. Nitrogen application significantly influenced SPAD. Maize cultivars and N rates with higher chlorophyll content had maximum yield. Cultivar responses to nitrogen rates significantly (P < 0.05) varied by crop year. Higher SPAD and NDVI values were associated with higher protein content. Therefore, SPAD and NDVI values could be used to analyse the nutrient requirements of maize under field conditions to estimate grain yield.

Although the effects of fertiliser addition and liming on semi-natural grassland productivity and biomass quality are well documented, less is known about how fertilisers change plant functional groups and mean ecological values. We researched the effects of liming (no lime and lime with 1 t/ha) and mineral fertilisers (control – no fertilisers, PK-P60K60, N20PK-N20P60K60, N80PK-N80P60K60, and N140PK-N140P60K60) for nine years on the Danthonia alpina Vest. grassland community. Based on Brown-Blanquet cover abundance, we calculated Shannon-Wiener evenness and abundance of plant functional groups (based on height, canopy structure, storage organs presence and flowering duration). We also researched Landolt’s ecological indicator values for nutrients, moisture, reaction, light, and temperature. Results revealed that fertilisers stimulated tall species with longer flowering duration. Shannon-Wiener evenness in control was 0.45, and N20PK increased to 0.71 but significantly decreased in treatment N140PK (0.25). Mean Landolt ecological value for nutrients and moisture increased while temperature dropped. The coverage of legumes and Landolt indicator value for nutrients increased because of the lime application, while the lime had no effect on Shannon-Wiener evenness and abundance of functional groups. Greater Shannon-Wiener evenness in treatments of PK and N20PK is a prerequisite for resistance to the effects of extreme climate events.

Vietnam’s Mekong River Delta (MRD), where rice is the dominant crop, is increasingly impacted by salinity intrusion, highlighting the need for alternative cropping options. This study evaluated the growth and yield performance of quinoa, beetroot, and maize under three irrigation salinity levels (0, 2 and 4 g/L), with and without rice straw mulch (7 t/ha), in greenhouse conditions representative of the MRD dry season. Agronomic traits, physiological parameters, and changes in soil, including electrical conductivity (ECe), soluble sodium (Sol-Na⁺), and exchangeable sodium percentage (ESP), were assessed. Results showed that quinoa demonstrated the greatest salinity tolerance, maintaining stable growth and yield under 4 g/L saline irrigation and soil ECe exceeding 15 dS/m. Beetroot’s yield was not significantly different under 2 g/L saline irrigation with straw mulching. Maize was highly sensitive to salinity and environmental stress, failing to complete its growth cycle under high heat and humidity, even in non-saline conditions. Across treatments, rice straw mulching significantly reduced soil ECe, Sol-Na⁺, and ESP, and improved crop performance under saline irrigation. Overall, quinoa and beetroot, especially when combined with mulching, offer promising alternatives for dry-season cropping in saline-prone areas of the MRD. In contrast, maize cultivation requires improved soil and environmental management under such conditions.

This study investigates the effects of salt stress and gamma irradiation on growth, biochemical, and physiological responses in three sugar beet (Beta vulgaris L.) cultivars. Control plants were irrigated with fresh water (EC = 1.1 dS/m), whereas salt stress was imposed with an irrigation of 9 dS/m. Seeds were irradiated with gamma rays (0, 50, 100, 200, 400 Gy) before sowing. Exposure to salt stress reduced root yield (RY), sugar yield (SY), chlorophyll content, and antioxidant enzyme activities (catalase (CAT) and superoxide dismutase (SOD)). In contrast, oxidative damage increased, as indicated by elevated malondialdehyde (MDA) concentrations. Interestingly, salt stress enhanced sugar content, with the Eudoro cultivar showing the greatest resilience, maintaining higher RY and SY and lower MDA compared to the other cultivars. Gamma irradiation at moderate doses (50–200 Gy) alleviated the effects of salt stress, with the strongest improvements in SY observed at 100 and 200 Gy. These treatments enhanced RY, chlorophyll content, and antioxidant activities, while also improving photosynthetic efficiency (Fv/Fm) and cellular integrity. Higher doses (> 200 Gy) reduced sugar content, indicating dose-specific effects. Eudoro exhibited superior salt tolerance, maintaining higher root and sugar yields (RY, SY) and reduced oxidative damage (lower MDA) under salt stress. These findings demonstrate that gamma irradiation at optimal doses enhances salt tolerance in sugar beet, offering cultivar-specific benefits for breeding programmes in saline environments.

Magnetic fields, as a form of physical energy, exert an influence on biological activities. However, our current understanding of the impact of magnetic fields on wheat yield remains limited. In this study, our objective was to investigate the effects of magnetic field treatment of wheat plants on their yield, root growth, absorption of nitrogen and phosphorus and soil bacterial diversity. The experiments were conducted at two agricultural research stations in China, Zhengzhou and Xuchang. Plants were treated with magnetic fields of 20, 40, 60, and 80 mT induced by permanent magnets for chronic exposure. Untreated plants were considered as controls. Our result showed that soil nutrients were found to have a substantial impact on wheat nitrogen and phosphorus absorption, and wheat nitrogen and phosphorus absorption significantly affected wheat yield. The change in soil nutrient content was caused by the change in soil bacterial community diversity and abundance, and increased soil nutrients increased wheat yield. The results suggest that magnetic field treatment stimulated wheat plant growth and yield, and changed soil nutrient content through improved soil bacterial community diversity and increased soil nitrogen and phosphorous absorption.

Restoration of Arrhenatherion meadows is limited both by the lack of local seed availability in natural habitats for self-restoration purposes and the lack of information on the germination of target species in these meadows. Understanding germination strategies can optimise local seed use. This study aimed to define germination strategies for groups of species based on relevant six germination parameters: germination capacity (GC), fresh ungerminated seed (FUS), median germination time, germination velocity, germination synchrony and germination uniformity. The germination test of 23 meadow species was performed according to ISTA (International Seed Testing Association) rules. The hierarchical clustering method and PCA biplot divided the species into five groups. Based on the Kruskal-Wallis and Dunn’s test, the evaluation of six parameters in five groups showed that species such as Arrhenatherum elatius, Centaurea jacea, Plantago lanceolata, Tragopogon pratensis and Dianthus deltoides differed significantly in terms of higher GC, lower FUS and faster germination velocity than Lathyrus pratensis, Vicia angustifolia and Geranium pratense. Conversely, these three species had more synchronous germination than species such as Knautia arvensis and Briza media and expressed the shortest peak of germination period among other species. These six parameters potentially describe germination strategies across groups of species.

Enhancing sustainability in agriculture requires innovative practices that boost crop productivity while conserving natural resources. This two-season field study (2023–2025) in sandy soils of El Sadat City, Egypt, evaluated the combined effects of nano-fertilisers and seed priming on the growth and yield of sugar beet (Beta vulgaris L.). Five fertilisation regimes, ranging from 100% conventional to 100% nano-formulations, were tested under both primed and unprimed seed treatments. The results demonstrated that the integration of nano-fertilisers with seed priming significantly improved sugar yield (up to 36.1 t/ha), sucrose content (20.35%), and nitrogen use efficiency (55.1 kg sugar/kg N). Post-harvest soil analysis showed improved nutrient retention, indicating enhanced environmental performance. This approach supports climate-smart agriculture by optimising nutrient input, reducing losses, and improving soil sustainability. Our findings highlight the potential of nano-agronomic inputs to contribute to global food security under conditions of climate change.

This work discusses the differences in the removal efficiency of heavy metals in soils along the China-Russia crude oil pipeline in different vegetation backgrounds. In this paper, two representative forest types, birch forest and larch forest, were selected for replicated sampling and experimental study in the soil of disturbed and undisturbed areas along the pipeline, respectively. The results showed that after ten years of vegetation restoration, the amount of heavy metals in the soil of birch and larch forests decreased, the Cu content in the soil under the background of the birch forest was higher than that of the larch forest, while the Zn, Mn and Pb contents were lower than that of the larch forest. The order of decreasing magnitude was Mn, Pb, Zn and Cu, and the overall decreasing rate of heavy metal content in larch forest soil was more obvious. The above conclusions indicate that vegetation restoration is an effective measure to alleviate soil heavy metal pollution.

The aim of this trial was to verify the influence of various autumn-applied nitrogen fertilisers on the growth, yield and quality of winter oilseed rape. In the three years, small-plot field trials were carried out at the Research Station Červený Újezd (50.0697044N, 14.1659086E). The hybrid cultivar DK Exstorm was chosen, with a sowing rate of 50 seeds/m2. Five fertilisation regimes were tested: (1) nitrogen-free control; (2) CAN (calcium ammonium nitrate); (3) ANU (ammonium nitrate urea); (4) U (urea), and (5) US (urea with N-(n-butyl)thiophosphoric acid triamide (NBPT) inhibitor). A uniform dose of 40 kg N/ha was applied at the end of October. Fertilisers U (leaf length, root collar diameter, leaf and root dry weight) and US (number of leaves and root length) had the best growth outcomes. The highest seed yields were obtained with US (5.83 t/ha) and ANU (5.82 t/ha) applications, which outperformed the unfertilised control by 0.65 and 0.64 t/ha, respectively. CAN fertiliser appears to be unsuitable for autumn fertilisation in terms of yield. There were no statistically significant differences in oil content (%) or thousand seed weight (g) between the treatments in any of the experimental years.

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.

Deep placement of controlled-release urea is an effective fertiliser management strategy for improving the maize productivity, but it is not clear whether and how controlled-release urea depth affects the stem and root lodging of spring maize. Two consecutive years of field experiments were conducted to elucidate stem and root lodging properties and their relationship between grain yield and lodging behaviours under various controlled-release urea placement depths. Results depicted that compared to broadcast nitrogen treatment (D0), deep controlled-release urea significantly decreased the stem lodging rate by 34.7–80.4%, which contributed to improving the mechanical characteristics of the internode by optimising the internode diameter and dry matter in the third basal internode as well as higher lignin content. In addition, due to a greater and deeper root system (root dry weight, root surface area, root length and root width) as well as larger angle, diameter, and tension of aerial root that significantly decreased root lodging rate (37.0–88.4%). Furthermore, deep placement of controlled-release urea significantly increased the 100-grain weight, grain number and harvested index by constructing a deeper and larger root system, which significantly improved maize grain yield by 14.2–38.5%, and the nitrogen use efficiency increased by 4.8–10.7%. The highest grain yield, nitrogen use efficiency and lowest lodging rate occurred in controlled-release urea placement depths of 15 cm. Hence, our study suggests that controlled-release urea placement depths of 15 cm were an efficient nitrogen fertiliser management strategy to improve crop productivity as well as lodging resistance in spring maize.

Low water availability is a significant constraint on global crop production. Exploration is needed regarding plant responses to drought in interaction with biochar, encompassing optimised water use and carbon allocation strategies. The size of the biochar particles also plays an important role, especially in influencing the dynamics of water and plant growth. This study explored the potential impact of biochar treatment on radish growth and drought tolerance. Finer biochar particles lead to the most substantial available water content for plants, increasing at around 30%, while medium and larger fractions increase by about 22% and 16%, respectively, compared to control soil. The chlorophyll fluorescence technique showed improved water management of drought stress at larger fractions of biochar. Our research underscores the potential of biochar treatments for environmental stresses and water scarcity in modern agriculture.

Clarifying the effects of meteorological factors on the growth and development of fresh maize after delayed sowing is important for selecting appropriate sowing dates and improving yield. Six sowing dates (B1 (March 10); B2 (March 20); B3 (March 30); B4 (April 9); B5 (April 19), and B6 (April 29)) and three fresh maize cultivars (A1 (Wan Nuo 2000); A2 (Nongke Nuo 336), and A3 (Caitian Nuo 6)) were chosen for experiments conducted between 2021 and 2022 in Guiyang, Qingzhen City, China. The results showed that the whole growth period and sowing-silking period were significantly reduced with delayed sowing, while the grain-filling period was relatively stable. Delayed sowing was beneficial in increasing the number of endosperm cells and the weight of the hundred kernels. The graining filling rate and the activities of four key starch synthesis enzymes (sucrose synthase, ADP-glucose pyrophosphorylase, starch branching enzyme, and starch debranching enzyme) were significantly influenced by light, temperature, and precipitation, and they mainly affected the hundred kernel weight. The yield tended to increase with delayed sowing, and the correlation analysis between precipitation and yield at different sowing periods showed a significant effect of precipitation on yield. Delaying the sowing to mid-early April was more favourable for grain filling, enhanced key enzyme activity, and increased the kernel weight and yield. These results highlight the importance of choosing excellent cultivars and matching them with the most suitable sowing date to fully exploit climatic resources and achieve high-yield and high-efficiency cultivation of fresh maize.

Coastal wetlands play a vital role in the migration and transformation of heavy metal pollutants in watersheds. There were 30 surface sediment samples that were analysed to investigate the distribution and ecological risks of heavy metals in the coastal wetlands around the Bohai Sea. Our results showed that the average concentrations of Pb, Cr, Ni, Cu, Zn, and Cd in these wetlands were 17.92 ± 5.81, 50.29 ± 20.50, 31.53 ± 9.71, 25.37 ± 4.29, 80.13 ± 15.11, and 0.92 ± 0.54 mg/kg, respectively. Relative to other wetlands, Pb (25.43 ± 2.68 mg/kg) and Cd (1.67 ± 0.06 mg/kg) contents were higher in the Liaohe Delta wetland (LHDW). Cu (28.44 ± 3.71 mg/kg), Cr (83.11 ± 5.80 mg/kg), and Ni (45.91 ± 3.02 mg/kg) contents were higher in the Yellow River Delta wetland (YRDW). The Zn (120.86 ± 7.41 mg/kg) content was higher in the Qilihai wetland. Heavy metal concentrations in coastal wetland sediments are shown to be positively correlated with organic matter content. Our results showed that the concentration of heavy metals decreases with increasing sediment particle size. In this study, Cd showed the highest pollution index and, therefore, more attention should be paid to the potential ecological risks of Cd in coastal wetlands around the Bohai Sea, especially in the LHDW and YRDW.

Today, there is widespread concern about the potential health effects on populations from consuming contaminated leafy plants and vegetables. In this study, heavy metal content is present in commonly consumed leafy plants (Atriplex hortensis, Spinacia oleracea, Urtica dioica, Beta vulgaris, and Brassica oleracea) from the mining area near Tuzla in Bosnia and Herzegovina was determined. After the preparation of the samples by wet digestion with HNO3, the flame and graphite furnace atomic absorption spectrometry was used. According to the results, the lowest concentration in leafy plants was obtained for Cr 0.08 mg/kg (Brassica oleracea) and the highest for Fe 539.15 mg/kg (Spinacia oleracea). The novelty of this study was to estimate health risk assessment for selected leafy plants. The estimated daily intake (EDI) of Pb, Mn, Zn, and Cd from consuming leafy plants was higher than the maximum tolerated daily intake. For adults, the total target hazard quotient (THQ) calculated based on EDI of the heavy metals was found to be > 1 for Pb and Cd due to all leafy plant consumption and for the children risk level of THQ was observed for most heavy metals. The hazard index due to the intake of toxic metals from ingesting leafy plants was much > 1. According to the total carcinogenic risk index for adults and children, the carcinogenic risks for all samples were higher than the tolerable range. Based on the results of this study, there is a significant non-carcinogenic and carcinogenic health risk to the population associated with the consumption of leafy plants cultivated in the mining area.

Partial slow-release fertiliser substitution for urea combined with water-saving irrigation may synergistically improve rice yield, quality, water, and nitrogen (N) utilisation. A field experiment to evaluate different combinations of irrigation regimes: alternate wetting and drying irrigation (AWD) and flooding irrigation (FI), and N strategies: N0 (no N fertiliser); N1 (100% conventional fertiliser); N2 (100% SCF – sulphur-coated fertiliser); N3 (70% SCF + 30% urea), and N4 (50% SCF + 50% urea) on efficient rice production. Results indicated that higher substitution rates of SCF (N2 and N3) increased total N and ammonia N in surface water, leachate, and soil while reducing nitrate N relative to N1. The N3 strategy showed the highest yields, dry matter, total N uptake, and water N utilisation due to a nutrient release pattern that matched rice growth requirements. AWD yielded 5% lower than FI, except for the N3 strategy, but protein content increased by 12%, and amylose content dropped by 17%. The structural equation model analysis suggested that SCF positively impacted yield by influencing surface water total N and soil total N. Our findings indicate that implementing AWD alongside a 70% SCF basal fertiliser and 30% urea topdressing can optimise rice yield and quality while effectively managing water and fertiliser resources in the middle-lower Yangtze River Basin.

The impact of toxic elements (TEs) contaminating the root zone of Lupinus angustifolius L. on enzymatic activities, nitrification rate, and changes in the root system was evaluated. Lupine was cultivated in a pot experiment using two types of soil – control and contamination (with a high degree of arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn) contamination). After harvesting lupine biomass, enzyme activities (β-glucosidase, acid phosphatase, arylsulphatase, lipase, chitinase, cellobiohydrolase, alanine aminopeptidase, and leucine aminopeptidase) in soils were analysed. Enzyme activities decreased with TE soil contamination. According to our results, arylsulphatase was found to be the most sensitive soil enzyme to TEs. The nitrification rate is closely related to soil contamination and plant activity, as it stimulates microbial growth and multiplication through root exudates. The close correlations confirmed this relationship (r = 0.73−0.99). An increasing trend in TE contents in the roots was observed with soil contamination. Plant hormones are crucial in regulating root growth and development under stress conditions. The levels of determined phytohormones in our experiment (auxins, abscisic acid (ABA), salicylic acid (SA), and bioactive cytokinins (bCKs)) were lower in the contamination compared to the control. Correlations confirmed a significant negative relationship between the TE content in the roots and the contents of phytohormones (auxins: r = –0.96 to –0.97; ABA: r = –0.83 to –0.86; SA: r = –0.95 to –0.99, bCKs: r = –0.87 to –0.93). The ratios of these hormones (not their absolute values) appear to be the determining factor for regulating root development and protecting plants from oxidative stress.

Earthworms dominate the soil biota, and different structural and functional features of their biology and ecology have been studied and exploited to evaluate their contributions as ecosystem services. Due to their feeding ecology, burrowing and casting activity, earthworms are involved in the nutrient cycles, and therefore it is opportune to be considered when the biogeochemical cycles of the terrestrial ecosystems are analysed. All structural, microbiological and biogeochemical impacts of earthworms in soil start with their feeding and digestive functions, which end in casting. The casting activity consisting of the excretion of the ingested soil and organic matter after digestion processes depends on earthworm feeding behaviours and ecology, even described in the current literature as a new ecological feature: the casting ecology. The complexity of the chemical relationships occurring inside earthworm casts between main nutrients (organic carbon, nitrogen, phosphorus, potassium, calcium) highlights the complexity of the biogeochemical cycles and the great earthworms’ contribution to these cycles in the ecosystems towards a better understanding of the soil sustainability through the soil biodiversity contribution. Due to this great contribution, the earthworms’ casts should be included as indicators in the integrative conservation management of the ecosystems, as a re-thinking of the concept of ecosystem sustainability.

A suitable irrigation pattern is of great significance for reducing greenhouse gas emissions. In this study, field experiments and a denitrification-decomposition (DNDC) model were used to study the global warming potential based on CH₄, N₂O and CO₂ fluxes under flooding irrigation and controlled irrigation in paddy fields in the Erhai Lake basin. The results showed that the average value of CH₄ flux under controlled irrigation was lower than that under flooding irrigation, with a reduction range of 43.21% to 48.88%, however, the average value of the N₂O and CO₂ fluxes from paddy field under controlled irrigation were higher than those under flooding irrigation. Controlled irrigation patterns can significantly reduce the global warming potential in paddy fields based on CH₄, N₂O and CO₂ fluxes. Controlled irrigation can effectively reduce the global warming potential per unit yield. For water management in the Erhai Lake basin, it is recommended the controlled irrigation treatment of soil moisture with an upper limit of 100% and a lower limit of 75–85% with irrigation, and a maximum surface water depth of 150–200 mm lasting for five days after precipitation from the jointing-booting stage to the milk stage.

We investigated, under field conditions and during four years (2018–2021) the effects of five irrigation levels (T1: 100% of crop water requirement; T2: 80% of T1; T3: 60% of T1; T4: 40% of T1, and T5: 0% of T1 – rainfed) in interaction with three planting densities (PD1: 54 900, PD2: 64 900, and PD3 75 200 plants/ha) on the yield, yield components and water use efficiency (WUE) of maize in Srem, Serbia. The results indicate a large year-to-year variability, mainly due to the total amount and distribution of rainfall. Water regime and PD interacted significantly. Irrigation increased grain yield 28, 34, 30 and 18% for treatments T1, T2, T3 and T4, respectively, compared to the T5; and significantly influenced the yield components. Planting density had significantly lower effects on grain yield compared to irrigation (+1.4–1.8%). WUE is maximised (3.436 kg/m3) at T4 under 75 200 plants/ha. Grain yield and WUE increased significantly with increasing PD, while the number of grains per ear and the weight of 1 000 grains decreased with increasing PD. In conclusion, limited irrigation at T2 under PD2 may be a viable method to maximise production efficiency and maize yield under the environmental conditions of this study and at sites with similar soil and climatic conditions.

In this study, a synergist made of itaconic acid, maleic acid, acrylic acid and other active ingredients polymerised was sprayed on the surface of nitrogen (N) fertiliser particles to make synergistic nitrogen fertilisers (SNF). To explore the effect of SNF on N metabolism of wheat in saline-alkaline land, five treatments were set up: CK – ordinary N fertiliser (299.86 kg N/ha); T1 – SNF (299.86 kg N/ha); T2 – SNF (239.89 kg N/ha); T3 – SNF (179.92 kg N/ha); T4 – SNF (119.94 kg N/ha). The aboveground dry weight of wheat, the photosynthetic characteristics of wheat flag leaves, the activity of the N metabolism enzyme of wheat flag leaves, the expression of N transporter-related genes in wheat roots, and the N accumulation and transport of plants were determined. The results showed that the T1 treatment performed the best. During the two years, the N translocation from stems and leaves to spikes of plants at maturity in T1 was 33.18–45.55% higher than that of CK. The N content of wheat spikes was 12.01–12.66% higher than that of CK. The activities of nitrate reductase, glutamine synthetase, glutamate synthetase and the expression of nitrate transporter gene TaNRT1.1 and ammonium transporter gene TaAMT1.1 were significantly higher than that of CK. The aboveground dry weight of wheat and photosynthetic characteristics of flag leaves were significantly higher than those of CK in T1, whereas the intercellular CO2 concentration was significantly lower than that of CK. The application of SNF positively affected N accumulation and transport in wheat, wheat yield, and fertiliser utilisation, as well as reduced N loss in saline-alkaline land.

Most farmers use urea as a nitrogen fertiliser to raise mustard (Brassica juncea L.), although its nitrogen (N) content is quickly lost due to its hygroscopic nature. Nitrogen loss in the form of nitrous oxide (N₂O) and nitrates (NO₃^–) has been causing low nitrogen fertiliser efficiency in vegetable cultivation. This investigation aims to assess the impact of urea fertiliser coated with biochar or activated charcoal on losses of N₂O and NO₃^– concentration in the soil during mustard production. The experiment used a randomised block design with five treatments of urea fertiliser coated with biochar/activated charcoal. The observed data included N₂O flux, nitrate, and ammonia content in soil and water. The results showed that urea fertiliser coated with activated charcoal from corn cobs tended to suppress N loss more effectively than urea coated with biochar or activated charcoal from coconut shells. Biochar and activated charcoal from coconut shells suppressed N-N₂O loss as much as 3.1% and 52.5% (7 days after planting (DAP)), respectively, and 68.7% and 71.6% (21 DAP), respectively. Biochar and activated charcoal from corn cob reduce N-N₂O loss by 46.5% and 66.5% (7 DAP), respectively, and by 70.7% and 77.8% (21 DAP). Urea-coated activated charcoal fertiliser increases mustard plant biomass and nitrogen uptake. Biochar and activated charcoal from coconut shells and corncobs increase nitrogen use efficiency by 5, 24, 6, and 17%, respectively. Biochar/activated charcoal coatings are a promising technology for boosting nitrogen use efficiency in vegetable crops, including mustard crops.

Biochar has demonstrated potential for stabilising high yields and sequestering carbon in dryland farmland, but it is unclear whether biochar affects the carbon sequestration capacity and carbon balance of annual farmland ecosystems. For this purpose, we conducted a plot control trial in salinised farmland in 2019–2021, where we set three treatments, control, and two biochar rates, 0 (CK), 15 (B15), and 30 t/ha (B30). The results showed that biochar application decreased soil organic carbon stocks in the early part of the experiment (first freeze and freeze period); these increased in the later part, and overall, the biochar treatments increased soil organic carbon storage by 3–6% compared with the control. Compared with the control (CK), biochar inhibited the total soil respiration rate and microbial respiration rate significantly (P < 0.05) during the crop growing period compared with the freeze-thaw period. After two years of freeze-thaw cycling, biochar application increased sunflower plant carbon sequestration and net primary productivity and suppressed total soil microbial respiration, thereby increasing net ecosystem productivity. Therefore, the application of biochar is conducive to carbon sequestration in farmland ecosystems and presents a carbon sink effect, thus being a good choice for improving the soil carbon pool and reducing emissions in the northern dry zone.

This paper studied the response of rice yield and soil nitrogen (N) cycling microorganisms to the combined application of animal slurry and mineral fertiliser. A pot experiment was conducted on typical yellow-brown paddy soil. There were five treatments: (1) CK – no N fertilisation; (2) S0 – mineral fertilisation; (3) S30 – 30% slurry with 70% mineral fertilisation; (4) S60 – 60% slurry with 40% mineral fertilisation; and (5) S100 – slurry application. Rice yield, yield components, and soil properties were investigated at harvest. The abundance of soil N cycle functional genes abundance was quantified via quantitative real-time PCR. The rice yield reached a high level when the proportion of slurry used to replace mineral fertiliser was 30–50%. The yield in response to mineral fertiliser (S0) was equivalent to that in response to no N fertilisation since the formation of effective panicles was inhibited. With the slurry replacement ratio increase, the available phosphorus and potassium contents in the soil improved, but the nitrate content decreased. Considering the entire soil N cycle, nitrogen-fixing microbes (nifH), ammonia-oxidising archaea (AOA amoA) and nitrite-reducing microbes (nirS and nirK) had greater abundances, reaching 108 copies. Compared with those in the S0 treatment, the abundances of most N cycle functional genes in the S30 treatment, except for napA, significantly increased from 31.2% to 100.9%, and the increase in the abundance of nirS and nosZ in the S100 treatment reached 4 times, which was obviously greater than that of the other genes. Correlation analysis revealed that high soil pH promoted N fixation and nitrification, while NH₄⁺-N had the opposite effect on N fixation and nitrification, and available phosphorus and potassium actively influenced denitrification. These results showed that a 30–50% slurry application ratio was recommended for rice, which was beneficial for maintaining high yields and high abundances of soil N cycle functional genes.

A three-year field experiment was carried out to investigate the methane (CH₄) and nitrous oxide (N₂O) emissions and calculate the global warming potential (GWP) according to all energy input in response to the nitrogen (N) rate in the typical rice-wheat rotation system in Jiangsu, China. Four N treatments, including R220W180 (local practice), R220W140 (cutting 10% total N in wheat season), R180W180 (cutting 10% total N in rice season) and R180W140 (cutting 20% total N in rice and wheat seasons separately), were designed in the study. Results showed that annual CH₄ emission was decreased by 25.7% in response to cutting 20% N, which was ascribed to the 24.6% reduction of CH₄ emission in rice season (P < 0.05) compared to local practice. The mitigation of N₂O emissions in R220W140 and R180R180 treatments contributed to the 8.5% and 15.7% decrease in annual N₂O emission, which was the 23.5% decrease in cutting 20% N treatment compared to local practice, respectively. Specifically, under the same amount of N rate condition (10% N cutting), the transfer N from rice season (R220W140) to wheat season (R180W180) led to the 8.5% increase in N₂O emission (P < 0.05). In the end, the cutting of 20% N decreased GWP and yield-scale GWP by 19% and 17%, which mainly originated from CH₄ and N₂O emissions. However, cutting N did not significantly decrease grain yield (P > 0.05). These results suggested that the 180 kg N/ha for rice and 140 kg N/ha for wheat in one rotation season were the beneficial N rate to achieve the co-benefit of yield and GWP in the typical rice-wheat rotation system in Jiangsu, China.

In recent years, sulfur inputs into the soil have greatly diminished due to the significant decrease in SO₂ emissions. Plant nutrients, like sulfur, can be released by the mineralisation of soil organic matter (SOM), which is a complicated mixture of substances (or fractions) like glomalin-related soil protein (GRSP) and fulvic acids (FA), humic acids (HA), humic substances (HS) and others. GRSP, FA, HA, and HS content, as well as the content of mineral and organic fractions of sulfur, was determined in different mineral and organic fertiliser treatments of the long-term field experiment. Using these results, the sulfur content in GRSP was calculated based on the soil’s organic matter carbon and soil’s organic bound sulfur (C_SOM/S_ORG) ratio. Sulfur content in GRSP was 4.08–5.46 (easily extractable GRSP), 9.77–15.7 (difficultly extractable GRSP), and 13.9–21.1 (total GRSP) mg S/kg of soil. Overall, the application of the organic fertiliser caused an increase in S content bound to GRSP. A strong significant relationship was also observed between GRSP fractions and soil organic sulfur. A similar relationship was also observed for the HA and HS with organic sulfur.

Increased levels of the non-essential hazardous metalloid arsenic (As) in rice grains pose a threat to human health and the sustainability of the rice industry. In several counties, the average As contamination in polished rice has been detected to range from 0.002 to 0.39 mg/kg, which is above the safe limit of 1 mg/kg as recommended by the World Health Organisation. Beyond this limit, the digestive tract, circulatory system, skin, liver, kidney, nervous system and heart can be affected. Humans can develop cancer from consuming or inhaling As. In addition, long-term exposure to drinking water contaminated with arsenic has also been linked to a dose-response relationship with an increased risk of hypertension and diabetes mellitus. Rice has been shown to be an indirect source of arsenic accumulation in human bodies. Under flooded paddy soil, trivalent arsenate (AsIII) occupies 87–94% of the total As, while under non-flooded soil, pentavalent arsenate (AsV) predominates (73–96% of the total As). This review aims to provide a thorough and interdisciplinary understanding of the behaviour of As in the paddy soil and transportation to rice grain and further investigate efficient ways to limit arsenic contamination. Supplementation of soil with specific mineral nutrients such as iron (Fe), sulphur (S) and silicon (Si) can significantly decrease the arsenic accumulation in rice grain by minimising its uptake and translocation. The hydrogen bonding potentials of uronic acids, proteins and amino sugars on the extracellular surface of soil microorganisms facilitate the detoxification of arsenic species. Further, rice is absorbed less when exposed to aerobic water management practices than anaerobic ones since it reduces the build-up of As in rice, and the solution is immobilised as in the soil.

The aim of this study was to evaluate the effects of continuous application of rice straw and biochar for 10 years on soil humus composition and structure in paddy soil. A 10-year field experiment was conducted in a paddy field and included three treatments: rice straw biochar (SC); rice straw (RS), no biochar or rice straw. The elemental analyser, Fourier transform infrared (FT-IR) spectrum, and three-dimensional excitation-emission matrix (3D EEM) fluorescence spectroscopy with fluorescence regional integration (FRI) analysis were used to study the soil humus composition and structure under different treatments. The results verified that the incorporation of rice straw and biochar significantly improved soil pH values and the soil organic carbon contents compared with the control. Rice straw significantly increased the contents of extractable humus, humic acid (HA) and fulvic acid in soil, while biochar only significantly affected HA and humic degree values. The molecular structure of HA affected by biochar is characterised by high humification and aromaticity, but rice straw increased the aliphaticity of the HA structure, as presented by elemental composition. Moreover, 3D EEM spectroscopy combined with FRI analysis showed that RS treatment formed soil humus had more aliphatic compounds, while SC treatment increased the aromatic components of humus. These results suggest that rice straw promotes the renewal of humus, and biochar enhances the humification degree of humus and the aromaticity of HA.