Microplastics are persistent contaminants of agricultural soils and may affect soil structure, microbial activity, nutrient cycling, crop growth, and the quality of plant-derived foods. Wheat (Triticum aestivum L.) deserves specific attention because it is a major staple crop, develops an extensive fibrous root system in cultivated soil, and produces grain that is consumed directly by humans. These characteristics create a close connection among soil contamination, rhizosphere processes, crop performance, and possible food-chain exposure. Unlike broader reviews of microplastics in crops, this review follows the pathway from particle entry into wheat-growing soils to transport, transformation, rhizosphere interactions, wheat responses, and possible contamination of edible grain. The movement and effects of microplastics depend on particle size, shape, polymer type, density, surface properties, aging, soil texture, mineral composition, organic matter, water movement, root activity, and soil organisms. Available studies show that plastic particles can alter root development, nutrient acquisition, oxidative balance, photosynthesis, biomass, and yield, although the direction and magnitude of these effects differ among experimental conditions. Evidence for root internalization and vascular transport is strongest for nanoplastics and submicrometer particles under controlled conditions. Direct field evidence for the accumulation of larger microplastics in mature wheat grain remains limited. Important research gaps include the scarcity of field measurements, the use of unrealistic exposure concentrations, poor separation of microplastic and nanoplastic evidence, uncertain root-to-grain transfer, and the lack of standardized analytical methods. Future research should combine realistic field exposure, aged and mixed-polymer particles, multi-season experiments, advanced particle tracing, and contamination-controlled analysis of wheat tissues and grain.

The AOP gene family is central to the biosynthesis of aliphatic alkenyl glucosinolates, which are key secondary metabolites in plants that are crucial for defense against herbivores and pathogens, as well as contribute to flavor and anti-carcinogenic properties in Brassica species. Despite their biological significance, the AOP family in cotton (Gossypium spp.) has not yet been systematically characterized. A comprehensive genome-wide analysis of AOP genes was conducted across four economically significant cotton species: G. arboreum (Gar, 28 genes) and G. raimondii (Gra, 29 genes), the diploids, and G. hirsutum (Ghi, 56 genes) and G. barbadense (Gba, 46 genes), the tetraploids. Our evaluation, including phylogenetic relationships, conserved motif identification, gene structure organization, chromosomal localization, and synteny analysis, revealed that the growth of the AOP family in cotton was primarily driven by segmental duplication events under strong purifying selection. Furthermore, qRT-PCR expression profiling of GhiAOP genes in G. hirsutum demonstrated distinct tissue-specific expression patterns, suggesting specialized functional roles in different plant organs. Overall, these findings offer a valuable new understanding of the evolution and adaptive diversification of AOP genes in cotton and highlight potential targets for strengthening plant defense mechanisms and agronomic traits employing genetic engineering.

The sustainability, crop production, and food safety of agriculture are increasingly challenged by microplastic pollution, as agricultural soils are the largest reservoirs and may serve as points of contact for plastic particles in the food chain. This review provides a comprehensive overview of plant materials, fate and uptake pathways, detection techniques, and the possible risks of microplastics in agriculture. Agroecosystems are also a source of microplastics, such as plastic mulch films, sewage sludge, compost and manure additives, wastewater irrigation, polymer-coated fertilizers, greenhouse materials, atmospheric deposition, and decomposition of discarded agricultural plastics. Their distribution and mobility in soil are controlled by polymer composition, particle size, morphology, density, surface ageing, soil texture, organic matter content, tillage practices, runoff, leaching, and soil biota. Recent data show that microplastics, especially smaller microplastics and nanoplastics, can attach to root surfaces, penetrate plants via cracks in roots, areas of lateral root development, and apoplastic pathways, and eventually move to tissues aboveground. Plant tissue detection is often accomplished by digestion of the sample, density separation, visual and fluorescence microscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, pyrolysis–gas chromatography mass spectrometry, and electron microscopy, but standardization of these methods remains a significant challenge. Microplastics can disrupt seed germination, root structure, nutrient absorption, photosynthesis, oxidative homeostasis, biomass buildup, yield development, and quality. Further, their capacity to transport additives, plasticizers, heavy metals, and persistent organic pollutants raises concerns about the transfer of contaminants to edible plant parts and their potential transfer to human diets. Further studies are needed focusing on field-realistic exposure conditions, long-term crop–soil interactions, nanoplastics behaviour, standardised analysis procedures, uptake and translocation pathways, edible crop risk assessments, and sustainable mitigation approaches to reduce microplastics in agroecosystems.

Excessive application of conventional chemical nitrogen (N) fertilizers tends to cause a series of problems such as soil acidification and compaction, and restrict further yield gains. New-type fertilizers such as carbon-based fertilizer (CBF) and slow-release fertilizer (SRF) have been shown to improve soil fertility and increase wheat yield. However, systematic comparisons of their yield-enhancing potential and the mechanisms by which they improve soil properties remain limited. In this study, two CBFs (CBF1, N-P2O5-K2O=24%-12%-8%; CBF2, N-P2O5-K2O=24%-10%-10%), polymer-coated urea (PCU, 45% N), sulfur-coated urea (SCU, 37% N), and conventional urea (urea, 46% N) were used as materials to elucidate mechanistic differences among fertilizer types in the regulation of soil nitrate-N dynamics, soil physicochemical properties, and soil microbial community structure in wheat fields. Our objective was to identify fertilization strategies that simultaneously enhance wheat yield and improve soil quality. The results showed that CBF1 and CBF2 reduced the early peak concentrations of soil nitrate-N following basal and topdressing fertilization relative to Urea, while providing a more balanced nitrate-N supply across early and late wheat growth stages, which maintained higher soil nitrate-N levels than Urea from overwintering to jointing and from anthesis to maturity. Compared with CBF1, CBF2 showed higher soil nitrate-N from anthesis to maturity, which was similar to PCU. With an appropriate N supply, CBF2 facilitated coordinated yield formation, significantly increasing grains per spike and total grain number. Adequate nutrient availability post-anthesis in CBF2 also facilitated grain filling, resulting in 4.08% and 6.77% increases in grain yield compared with SCU and Urea, respectively. Compared with urea, CBFs application effectively mitigated soil pH decline, enhanced soil electrical conductivity, and modulated soil enzyme activities, as well as soil bacterial diversity and community composition. On the one hand, CBFs decreased the relative abundance of nitrifying bacteria (e.g., Nitrospirota_A), thereby suppressing soil nitrification, regulating soil nitrate concentrations, and consequently reducing the relative abundance of denitrifying bacteria such as Proteobacteria, Actinobacteriota, and Firmicutes_D, which decreased the potential risk of N₂O emissions. On the other hand, CBFs application altered the relative abundance of microbial groups involved in soil carbon cycling such as Bacteroidota and Gemmatimonadota, thereby enhancing soil nutrient availability and increasing the contents of soil organic matter, available P, and available K. In general, both CBF2 and PCU optimized soil nutrient supply and increased wheat yield, whereas CBF2 was more favorable for improving soil physicochemical properties and enhancing soil fertility, which is expected to promote the synergistic improvement of wheat production potential and soil quality.

The aggravation of ozone (O3) pollution poses a significant threat to agricultural production. With China being the leading wheat producer of the world, contributing 17.8% to global output, the vulnerability of wheat to O3 is of particular concern. Despite extensive research on the impacts of O3 on wheat production and the ongoing development of new wheat cultivars over the years, a connection between yield loss and the released ages of wheat cultivars under O3 stress remains unestablished. Addressing this, the experiment was carried out at the Yangzhou Rice and Wheat Free-air Gas Concentration Enrichment (FACE) Testing Base in China, using 17 wheat cultivars developed since the 1970s as experimental materials. The elevated O3 concentration in the test was 1.5 times higher than that in a normal atmosphere. The results indicated that O3 led to a significant reduction in wheat yield of 18.19%. The yield of cultivars released in the 1970s, 1980s, 1990s, and after 2000, decreased by 24.9%, 23.3%, 19.8%, and 14.7%, respectively. Overall, the direct effect of 1,000-grain weight on yield was the most significant, followed by the number of grains per spike, whereas the number of spikes contributed least to the yield components. To enhance resistance to O3 stress in future breeding efforts, increasing the 1,000-grain weight should be a primary objective. Our findings also revealed that elevated O3 concentration led to higher sedimentation values and protein content while lowering bulk density, hardness, and starch content. As the release age approaches, the rate of decrease in bulk density diminishes gradually. In terms of hardness, sedimentation value, and starch content, varieties released in the 1990s exhibited less sensitivity, whereas those released after the 2000s experienced the most significant changes in protein content. It is worth noting that the impact on the nutritional quality of modern cultivars is particularly significant, particularly regarding starch and protein content. Stress indices indicate that the cultivars released after 2000 exhibit stronger resistance to yield loss. The Yangmai series cultivars appear to be promising parental lines for future breeding programs aimed at developing O3-resistant wheat.

Nitrogen (N) input is crucial for increasing soil nutrients and improving crop root architecture. Slow-release N fertilizer has been expected to regulate soil nutrient supply in the middle and later growth stage of wheat, but its effect on root architecture and soil nutrients and their interactions remains unclear. The self-made root canal-soil column system was used to investigate the effects of sulfur-coated urea (SCU), urea (U) and compound fertilizer (CF) on the vertical distribution of wheat root and soil nutrients. The vertical distributions of root length, length density and dry weight in 0 − 90 cm soil layer increased first and then decreased after booting. Compared with U and CF treatment, SCU treatment increased the total root length by 26.16

The delayed sowing date and basal internode lodging caused by climate change are major constraints on wheat productivity. To investigate the effects of varying sowing dates and fertilization application regimes on wheat yield and lodging resistance, a two-year field experiment was conducted with two sowing dates and five fertilization application regimes. Results revealed that the T2 sowing period caused grain yield reductions of 43.82% and 29.82% over two consecutive years, accompanied by shortened second basal internode length and decreased plant height, although lignin content increased significantly. Among fertilization treatments, S4 effectively enhanced the mechanical strength of the second basal internode, achieving both higher yield and superior lodging resistance. We propose combining controlled-release nitrogen fertilizer (CRNF) with urea across different sowing dates to optimize productivity and stem stability. These strategies tackle climate-driven sowing delays and lodging while maximizing yield potential.

Microplastic contamination in agricultural soils is emerging as a significant environmental challenge due to its detrimental effects on soil health, nitrogen cycling, and crop productivity. This review paper synthesizes current knowledge on the impacts of various microplastics, specifically polyethylene (PE), polyvinyl chloride (PVC), and polypropylene (PP), on agricultural systems, with a particular focus on their interactions with nitrogen dynamics and ammonia volatilization processes. Microplastics enter agricultural soils through multiple sources, including plastic mulching, irrigation, and application of biosolids, leading to alterations in soil physical and chemical properties, nutrient availability, and microbial activity. These changes negatively influence critical soil processes such as nitrogen mineralization, nitrification, and denitrification, thereby reducing nitrogen use efficiency (NUE) and increasing ammonia volatilization. Consequently, these disturbances manifest in reduced crop growth and productivity, particularly affecting crops such as wheat. This review also explores biochar as a promising remediation strategy, highlighting its potential to mitigate microplastic-induced disruptions in soil ecosystems by improving soil structure, enhancing nitrogen retention, and reducing ammonia emissions. However, the paper identifies significant knowledge gaps, including the need for standardized methodologies and long-term field studies to understand the cumulative impacts of microplastics comprehensively. To address microplastic pollution effectively, integrated approaches combining scientific research, sustainable agricultural practices, and robust policy frameworks are recommended. This will ensure agricultural sustainability, soil fertility, and food security amidst growing environmental concerns.

Rice-wheat and maize-wheat rotations are major cropping systems in the middle and lower reaches of Yangtze River in China, where high nitrogen (N) inputs and low N efficiency often exacerbate resource waste and environmental pollution. Due to the changes in factors such as soil properties and moisture content, the N fate and the N utilization characteristics of wheat in different rotations are significantly different. Efficient N management strategies are thus urgently required for promoting maximum wheat yield in different rotation systems while reducing N loss. A 2-year field experiment using isotopic (15N) tracer technique was conducted to evaluate the fate of 15N-labeled urea in wheat fields and the distribution characteristics of N derived from different sources. The wheat yield and N use efficiency under various N rates (180 and 240 kg ha−1, abbreviated as N180 and N240) and preceding crops (rice and maize, abbreviated as R-wheat and M-wheat) were also investigated. The results showed that N240 increased N uptake and grain yield by only 8.77−14.97% and 2.51−4.49% compared with N 180, but decreased N agronomic efficiency (NAE) and N physiological efficiency (NPE) by 14.78−18.79% and 14.06−31.35%. N240 also decreased N recovery in plants by 2.8% on average compared with N180, and increased N residue in soil and N loss to the environment. Compared with that of basal N, the higher proportion of topdressing N was absorbed by wheat rather than lost to the environment. In addition, the accumulation of topdressing N in grain was much higher than that of basal N. Compared with that in R-wheat treatment, plants in M-wheat treatment trended to absorb more 15N and reduce unaccounted N loss, resulting in higher yield potential. Moreover, the M-wheat treatment increased N recovery in 0−20 cm soil but decreased 80−100 cm soil compared with R-wheat treatment, indicating a lower risk of N loss in deeper soil. Collectively, reducing N application rate and increasing the topdressing ratio is an effective way to balance sustainable crop yield for a secure food supply and environmental benefit, which is more urgent in rice-wheat rotation.

The growth regulator factor (GRF) is responsible for various plant biological processes. GRF proteins are transcription factors that play a significant role in the growth of plants. To determine the evolutionary trend, a genome-wide in-silico study of the GRF(TFs) family was performed on diploid cotton species (G. arboreum and G. raimondii) and allotetraploid (G. hirsutum and G. barbadense). We discovered 18 genes in G. arboreum that were non-redundant and encoded GRF proteins. These genes were given the name GarGRF (G. arboreum GRF). In G. Raimondi, we found 17 GRF genes; in G. barbadense, we found 31 GRF genes. Finally, in G. hirsutum, we found the maximum number of GRF genes, which was 34 (GhiGRF). Additionally, gene structure, conserved domain research, phylogenetic analysis, and physical location were explored for farmed diploid species (G. arboreum and G. raimondii) as well as tetraploid species (G. hirsutum and G. barbadense). In cultivated diploid (G. arboreum and G. raimondii) and tetraploid species, it has been proven that particular GRF genes play a significant role in the development of plants (G. hirsutum and G. barbadense). The germination of seeds and the growth of cotton depend on these genes, which play an essential role in both processes.

Controlled-release nitrogen fertilizer (CRNF) has been expected to save labor input, reduce environmental pollution, and increase yield in crop production. However, the economic feasibility is still controversial due to its high cost. To clarify the suitable application strategy of CRNF in promoting the yield, nitrogen use efficiency and income on wheat grown in paddy soil, four equal N patterns were designed in 2017−2021 with polymer-coated urea (PCU) and common urea as material, including PCU applied once pre-sowing (M1), PCU applied 60% at pre-sowing and 40% at re-greening (M2), 30% PCU and 30% urea applied at pre-sowing, 20% PCU and 20% urea applied at re-greening (M3), and urea applied at four stage (CK, Basal:tillering:jointing:booting=50%:10%:20%:20%). In addition, M4−M6, which reduced N by 10%, 20% and 30% respectively based on M3, were designed in 2019−2021 to explore their potential for N-saving and efficiency-improving. The results showed that, compared with CK, M1 did not significantly reduce yield, but decreased the average N recovery efficiency (NRE) and benefits by 1.63% and 357.71 CNY ha−1 in the four years, respectively. M2 and M3 promoted tiller-earing, delayed the decrease of leaf area index (LAI) at milk-ripening stage, and increased dry matter accumulation post-anthesis, thereby jointly increasing spike number and grain weight of wheat, which significantly increased yield and NRE compared with CK in 2017−2021. Due to the savings in N fertilizer costs, M3 achieved the highest economic benefits. With the 20% N reduction, M5 increased NRE by 16.95% on average while decreasing yield and net benefit by only 6.39% and 7.40% respectively, compared with M3. Although NRE could continue to increase, but the yield and benefits rapidly decreased after N reduction exceeds 20%. These results demonstrate that twice-split application of PCU combined with urea is conducive to achieving a joint increase in yield, NRE, and benefits. More importantly, it can also significantly improve the NRE without losing yield and benefits while saving 20% N input.

The abiotic stresses have contributed to a considerable decline in wheat productivity during the last few decades. Developing effective techniques for dealing with crop losses induced by abiotic stresses was necessary. Fertilizer-based systems are lowcost and easy to apply in any agricultural community, regardless of size. Under conditions of heat, salt, waterlogging, and combination stresses, this study investigated the effects of sulfur-coated urea (SCU Mixture = 30% SCU; Release period = 40 days, + 40% SCU; Release time = 120 days, + 30% SCU; Release time = 160 days, @ 130 kg/ha) on the production of wheat crop. The research was carried out using a fully randomized, three-replicate design. The PCA plot specified that the variables with the most significant influence on wheat yield were plant length, spike weight, and SPAD value. The SPAD values in control, waterlogging, salt, heat, and joint stresses were found to be 53, 31, 43, 15.2, and 12.2, respectively, when SCU Mix was applied at a degree of 130 kg N per ha. Up to the flowering stage, the net leaf photosynthetic rate increased in all stress treatments, reaching 17.38 mu molCO(2)m(-2)s(-1). In the control group, the spike length was 12 cm, but in the salt stress group, it was 11.6 cm. A crop yield of 9638 kg/ha under control, 8373 kg/ha under salt stress, and 3423 kg/ha under heat stress was shown. The plants found heat stress the most intolerable because it occurred during the flowering period. Nitrogen levels in the soil significantly correlated with growth, spike length, yield, and physiological constraints; nitrogen-related indicators showed a positive association. This study shows that SCU Mix, which appears ineffective in heat and combined stresses, can be an environmentally friendly alternative for wheat salt stress and waterlogging tolerance.

Silage maize is cultivated due to its high nutritional value as a forage. China’s recent agricultural policy promotes the popularization and cultivation of silage maize. The production of silage maize is affected by planting density and nitrogen application. Based on investigating the planting habits of local farmers, we adjusted the planting density and nitrogen application rate to optimize the growth of silage maize. This study was conducted to investigate the effects of planting density (65,000 plant ha−1 (D1), 80,000 plant ha−1 (D2), and 95,000 plant ha−1 (D3)) and nitrogen rate (150 kg ha−1 (N1), 230 kg ha−1 (N2), and 310 kg ha−1 (N3)) on growth, yield, and quality of silage maize using a two-factor random block design. Planting density and nitrogen fertilizer significantly affected plant height, stem diameter, leaf area index, crude protein, neutral detergent fiber, acid detergent fiber, and starch of silage maize. In summary, the combination of a planting density of 80,000 plants ha−1 and a nitrogen application rate of 310 kg ha−1 produced a higher crude protein and starch yield and better palatability and quality; this result can aid silage maize growth.

High loss and low nitrogen (N) efficiency in agricultural production is severe. Also, ammonia volatilization and N leaching aggravated environmental pollution. The eutrophication of surface water and the emissions of N2O increased, hence green fertilization management urgently needs to be rationalized. Coordinating N supply from different sources has been shown to reduce environmental pollution. Therefore, this study was dedicated to clarifying the transport of N sources in the rice-wheat rotation system. The stable isotope tracer technology was used to label fertilizer (F), soil (T), and straw (J) with 15N, respectively. The utilization of N by crops (the N ratio in organs), as well as the residual N in soil and loss status, were measured. According to the potential of response to N, all the wheat cultivars were divided into groups with high (HNV) and low efficiency (LNV). The N contribution ratio showed that 43.28%~45.70% of total N accumulation was from T, while 30.11%~41.73% and 13.82%~24.19% came from F and J. The trend in soil N residue (T > F > J) was consistent with the above, while it was the opposite in N loss (T< F< J). The seasonal effectiveness showed that T achieved the highest N utilization efficiency (31.83%~44.69%), followed by F (21.05%~39.18%) and J (11.02%~16.91%). The post-season sustainability showed that T decreased the most in soil N residue (2.08%~12.53%), and F decreased the most in N accumulation (9.64%~18.13%). However, J showed an increase in N recovery rate (2.87%~5.89%). N translocation and distribution showed that N from different sources in grains was significantly higher than that in stems, glumes, and leaves. The ratio of HNV (75.14%~79.62%) was higher than that of LNV (71.90%~74.59%) in grain, while it was the opposite in other organs. Plant N accumulation, soil N supply, and straw N transformation were determined jointly by the three N sources, thus reducing N loss and N2O production. Therefore, the results will highlight the insights for constructing local N and emission reduction models.

Soil salinity is a global issue that affects wheat production,and it is of great interest to improve the production efficiency of wheat in saline fields.A comprehensive understanding of salt-tolerance mechanisms and the selection of reliable screening indices are crucial for breeding salt-tolerant wheat cultivars.Previous studies have reported the performance of wheat under salt stress and controlled experimental conditions,such as potted plants,seawater （saltwater） irrigation,hydroponics,and salt ponds,but could not simulate the actual production environment in the field and reflect the law of crop growth in a natural state.How salinity stress affects wheat yield,and the physiological indicators that contribute to yield formation under saline field conditions are not yet to be established.Five spring wheat varieties with significant differences in salt tolerance （salt-tolerant varieties:‘NM21’‘YM20’‘YFM4’;saltsensitive varieties:‘YM23’‘AN1124’） screened in a previous experiment were grown at two sites with significantly different soil salinity,namely:non-saline (control,soil salinity before sowing was 0.770±0.062 g·kg -1 ) and saline (soil salinity before sowing was3.294±0.198 g·kg -1 ) fields,in Dafeng,Jiangsu,China.The yield and its components,post-anthesis chlorophyll content,chlorophyll fluorescence F v /F m ,malondialdehyde content,and proline content were measured.The results showed that the leaf area index,dry matter accumulation,and tillers number decreased significantly in saline field.Moreover,compared with the control,wheat yield in saline field decreased significantly and was only 26.2% of the control.The number of spikes,kernels per spike,and 1000-grain weight also decreased significantly.The number of spikes,which decreased by 60.7%,was the main constraint on yield production followed by the 1000-grain weight,which also decreased.Salt stress also caused a significant decrease in chlorophyll relative content（SPAD value） and chlorophyll fluorescence F v /F m but significantly increased the malondialdehyde and proline contents;the range of change differed among varieties.Salt-tolerant varieties had a lower decrease in chlorophyll content and chlorophyll fluorescence F v /F m and a lower increase in malondialdehyde content but a higher increase in proline content,therefore,there was a lower decrease in yield.Correlation analysis was carried out for the physiological characteristics at the flowering stage,yield,and its constituent factors in wheat with different salt tolerances.The results showed that there was a significant positive correlation between chlorophyll fluorescence F v /F m and the number of spikes,1000-grain weight,and yield,and SPAD value was positively correlated with dry matter accumulation.A significant positive correlation was observed between dry matter accumulation and the number of spikes 1000-grain weight,and yield,indicating that salt stress inhibits photosynthesis in wheat by reducing chlorophyll content and chlorophyll fluorescence F v /F m ,reducing the production of photosynthetic products,consequently resulting in a final yield reduction.Hence in field identification,SPAD value and chlorophyll fluorescence F v /F m at the flowering stage can be used as fast and reliable indices for salt tolerance in wheat.Furthermore,‘YM20’had the lowest yield reduction rate and better overall performance,making it suitable for planting in Dafeng saline land.

【Objectives】The experiment studied the effects of different phosphorus and potassium fertilizer application rates and methods on grain yield,protein content,NPK uptake,and utilization of wheat following rice,to provide a reference for optimizing yield and efficiency of rice-wheat rotation system.【Methods】 Field experiments with split plot design were carried out in Yizheng City,Jiangsu Province under rice and wheat rotation system from 2020 to 2021,and the teat wheat variety was low-gluten type,Ningmai 33,and all rice and wheat straw were returned to the field after harvest.The main factor was P fertilizer,including three primary base application 0,72,and 144 kg/hm~2（P0,P1,P2） treatment,and a basal plus topdressing at jointing stage at the rate of respective 72 kg/hm~2（P3）.K fertilizer was the secondary factor,with three primary base application treatments of 0,72,and 144 kg/hm~2（K0,K1,K2）,and one treatment of base plus topdressing at jointing stage at the rate of72 kg/hm~2 each time（K3）.Wheat biomass and grain yield were investigated,NPK and protein contents in plants and grains were analyzed at harvest.【Results】P and K fertilization had significant main effects and interaction on plant NPK accumulation,fertilizer use efficiency,grain yield and protein content.Appropriate P and K fertilization rate（72 kg/hm~2） improved their synergy effect,while excessive rate（144 kg/hm~2） offset or even led to negative impact,such as reducing fertilize efficiency and grain quality.Compared with P1,P2 did not significantly affect grain yield,protein content,N and K agronomic efficiency,but reduced P agronomic efficiency and the partial productivity of P fertilizer.Under the P0 condition,K2 had higher grain yield,PK accumulation than K1.Compared with P2,P3 did not affect grain yield,protein content and fertilizer use efficiency,and K3 did not affect grain yield and protein content compared with K2,but significantly increased the physiological use efficiency and agronomic efficiency of nitrogen and phosphorus.Among the combination treatments,P3K2,P1K2 and P1K3 performed better in terms of grain yield and fertilizer utilization than those containing P0,P2,and K1 rates.【Conclusions】Applying P fertilizer twice did not show superiority over single basal application,while two-time application of K fertilizer had a significantly higher effect than one basal application.In general,the combination of P 72 kg/hm~2 and K 144 kg/hm~2,regardless of frequency of application is recommended for low-gluten wheat variety,Ningmai 33 in less fertile sandy loam soil.

The extensive application of traditional fertilizer has greatly contributed to wheat yield, accompanied by massive nitrogen (N) loss and environmental pollution. Controlled-release nitrogen fertilizer (CRNF) is expected to improve N use efficiency (NUE) in agricultural systems. Unfortunately, the mechanism by which CRNF reduces N loss and its response to soil microbial communities remains unclear. In this study, common urea, polymer-coated urea (PCU), sulfur-coated urea (SCU) and urea-formaldehyde (UF) were used as materials to analyze the effects of split application of different N sources on wheat yield, NUE, soil N balance, soil bacterial diversity and functional abundance. The results showed that PCU and SCU significantly improved yield relative to urea, with an average increase of 18.20% and 15.73%, respectively. N uptake by wheat in PCU, SCU and UF was increased by 18.76%, 14.26% and 7.75% compared to that in urea, respectively. CRNF increased the mineral N content of the topsoil (0-20 cm) but decreased the mineral content in the deeper soil (40-60 cm). CRNF was observed to significantly decrease cumulative N2O emissions, as well as apparent N loss compared with urea, which was reduced by 39.45%, 30.74% and 11.68% in PCU, SCU and UF, respectively. In addition, PCU decreased soil bacterial diversity but increased the abundance of microbes involved in N cycle, such as Firmicutes, Actinobacteriota and Bacteroidota, which could regulate soil nitrate concentrations. The results indicated that split application of PCU was conducive to promoting N uptake by wheat, increasing topsoil mineral N content, reducing N leaching into deeper soil and N2O emissions, thereby alleviating N loss while increasing NUE and wheat yield.

IntroductionThe evaluation on the trade-off/synergy relationship of urban cultivated land-use function conflicts (CLUFCs) for improving the sustainability of cultivated land ecosystem is one of the solutions to coordinate the contradiction between land health and economic development and alleviate food crises, and achieve “zero hunger” in the United Nations Sustainable Development Goals (SDGs).MethodsIn this study, Yancheng City was taken as the research object, and the cultivated land ecological function (CLEF) was evaluated by the morphological spatial pattern analysis-minimum cumulative resistance (MSPA-MCR) model from the perspective of multi-objective coordinated development of cultivated land, and cultivated land productive function (CLPF) was evaluated by net primary productivity (NPP). In addition, combined with local indications of spatial association (LISA) analysis, the spatial trade-off/synergy relationship between CLPF and CLEF was quantified and analyzed. The spatial principal co-coordinates-redundancy analysis (SPCoA-RDA) was used to explore the influencing factors and mechanisms of CLUFCs.ResultsThe results show that there are obvious spatial heterogeneity and aggregation distribution characteristics of CLUFCs in Yancheng City. Through SPCoA-RDA, it is found that the spatial differentiation of CLUFCs is the result of the combination of internal (population density, road network, and water network) and external (spatial spillover effect) driving factors.DiscussionBased on these results, the study area was divided into eight types of cultivated land suitability zones under four aggregation relationships of CLUFCs. Comprehensively considering production, CLUFCs were evaluated by socio-economic and geo-spatial statistical dates, and strategies for guiding the coordinated development and sustainable management of urban cultivated land had been put forward. This study can provide a theoretical framework and certain feasible suggestions for the sustainable development and the transformation of cultivated land system in agriculture cities.

Genetic improvement has promoted wheat’s grain yield and nitrogen use efficiency（NUE） during the past decades.Therefore, the current wheat cultivars exhibit higher grain yield and NUE than previous cultivars in the Yangtze River Basin, China since the 2000s. However, the critical traits and mechanisms of the increased grain yield and NUE remain unknown. This study explores the mechanisms underlying these new cultivars’ increased grain yield and NUE by studying 21 local cultivars cultivated for three growing seasons from 2016 to 2019. Significantly positive correlations were observed between grain yield and NUE in the three years. The cultivars were grouped into high（HH）, medium（MM）, and low（LL） grain yield and NUE groups. The HH group exhibited significantly high grain yield and NUE. High grain yield was attributed to more effective ears by high tiller fertility and greater single-spike yield by increasing postanthesis single-stem biomass. Compared to other groups, the HH group demonstrated a longer leaf stay-green ability and a greater flag leaf photosynthetic rate after anthesis. It also showed higher N accumulation at pre-anthesis, which contributed to increasing N accumulation per stem, including stem and leaf sheath, leaf blade, and unit leaf area at preanthesis, and promoting N uptake efficiency, the main contribution of high NUE. Moreover, tiller fertility was positively related to N accumulation per stem, N accumulation per unit leaf area, leaf stay-green ability, and flag leaf photosynthetic rate, which indicates that improving tiller fertility promoted N uptake, leaf N accumulation, and photosynthetic ability,thereby achieving synchronous improvements in grain yield and NUE. Therefore, tiller fertility is proposed as an important kernel indicator that can be used in the breeding and management of cultivars to improve agricultural efficiency and sustainability.

为研究包膜尿素对稻茬小麦抗倒伏性能的调控效应,探讨协调稻茬小麦产量和抗倒伏性能的包膜尿素合理施用方式,采用树脂包膜尿素(PCU)和硫包膜尿素(SCU)为材料,设计3种施肥模式:包膜尿素一次性基施(N1);60％ 包膜尿素基施+40％ 普通尿素拔节期追施(N2);60％ 包膜尿素基施+40％ 包膜尿素返青期追施(N3),以普通尿素60％ 基施+40％ 返青期追施为对照(CK),分析不同包膜尿素及施肥模式下稻茬小麦茎秆形态特征、抗倒伏能力和产量等的差异.结果表明,N1模式与CK相比显著降低小麦基部第2节间长度,提高其充实度、茎秆粗度和秆壁厚度,增强茎秆抗折力和抗倒伏指数;PCUN1和SCUN1田间实际倒伏系数分别仅为1.11和1.31,但产量较低,与CK均无显著差异.与N1模式相比,N2模式显著降低小麦开花期、乳熟期和蜡熟期基部第2节间充实度和抗倒伏指数,显著提高小麦田间倒伏率和倒伏系数;N3模式产量水平最高,在两种包膜尿素中均显著高于N1、N2模式和CK,倒伏率和倒伏系数与N2模式无显著差异,但显著低于CK.在N3模式下,PCU产量最高,较CK增产14.75％,基部第2节间长度显著低于SCU,基部第2节间充实度、茎秆粗度和秆壁厚度均显著高于SCU,且田间倒伏率和倒伏系数均呈低于SCU的趋势.综上,树脂包膜尿素基施(60％)加返青期追施(40％)能一定程度上控制茎秆基部第2节间长度,提高其充实度和抗折力,降低小麦倒伏系数,并且实现较高的产量增幅,是有利于协调稻茬小麦高产与抗倒伏的施肥方式.