Introduction:In the water-limited Loess Plateau of China, wheat productivity faces severe constraints. This study investigates the physiological and quality determinants of yield and protein content across multiple winter wheat cultivars to identify key breeding targets for dryland systems. Methods:Eleven cultivars were analyzed for soil water storage dynamics, dry matter accumulation and translocation, nitrogen use efficiency, and grain quality parameters, including volatile flavor compounds. Results:High yield potential was driven by superior pre-anthesis nitrogen assimilation and substantial post-anthesis dry matter remobilization. The highest-yielding cultivar (YH-805) achieved this through a greater number of grains per spike. Conversely, higher grain protein content (e.g., in YH-618) was linked to enhanced post-flowering nitrogen translocation. A fundamental yield-protein trade-off was confirmed. The medium-yield, high-protein cultivar YH-115 exhibited the most favorable flavor profile, associated with key volatile compounds like octanal and hexanal. Discussion:The results demonstrate that yield and quality are governed by distinct pre- and post-anthesis resource allocation strategies. Targeted breeding for specific traits-such as pre-anthesis nitrogen uptake for yield or post-anthesis nitrogen translocation for protein-can help optimize for either enhanced productivity or superior end-use quality in dryland wheat systems.

BACKGROUND:In winter wheat, low nitrogen (N) and zinc efficiency limits production. Although combined application boosts yield and grain zinc, the underlying mechanisms and optimal rates remain unclear. This study aims to uncover these mechanisms and identify the best management strategy. RESULTS:Applying N at 240 kg ha-1 significantly enhanced post-anthesis glutamine synthetase (GS) and glutamate synthase (GOGAT) activities in flag leaves compared to 180 kg ha-1, promoting pre-anthesis N translocation and post-anthesis N accumulation. This extended the grain-filling period by 0.8-1.44 days, increased the maximum grain-filling rate by 3.11-12.30% and boosted yield by 6-8% through improvements in spike number, grains per spike and thousand-kernel weight. Grain Zn concentration and Zn use efficiency increased by 12-21% and 35%, respectively, but N uptake and utilization efficiency declined. Foliar Zn application at anthesis (2.4 kg ha-1) further enhanced GS and GOGAT activities during grain filling, increased post-anthesis N accumulation and improved the grain-filling rate by 0.63-9.96%. This raised thousand-kernel weight by 0.70-10.97% and yield by 0.71-5.78%. Grain Zn concentration reached 40.59-41.12 mg kg-1, whereas N uptake efficiency and partial factor productivity of N increased by 1.94-11.61% and 0.71-5.78%. Correlation analysis indicated strong associations of yield with grain N accumulation, post-anthesis GS/GOGAT activities and N partial factor productivity, whereas grain Zn concentration correlated with Zn use efficiency and post-anthesis N metabolism. CONCLUSION:The combination of N at 240 kg ha-1 and foliar Zn at 2.4 kg ha-1 during anthesis optimized post-anthesis N metabolism, prolonged grain filling and synergistically improved yield, grain Zn content and NZn efficiency. © 2026 Society of Chemical Industry.

Sustainable nitrogen (N) management is critical for enhancing wheat production in the water-limited environment of China’s Loess Plateau. This study investigated the effects of four N rates (0, 120, 180, and 240 kg N ha−1) and two sowing methods, furrow sowing (FS) and drill sowing (DS), on wheat yield, grain quality, and water-use efficiency (WUE). Results indicated that N application significantly improved all metrics. The optimal N rate for yield was 180 kg N ha−1 (N180), producing yields equivalent to the higher 240 kg N ha−1 rate (N240). Compared to the N0 control, the N240 treatment under FS in 2022–23 increased grain yield by 25.4% and WUE by 11.9%, while under DS it increased yield by 23.6% and WUE by 11.1%. However, in the following year (2023–24), the greatest benefits under FS came from N180, which increased yield by 19.3% and WUE by 11.5% over the control. Higher N rates markedly elevated grain quality: N240 resulted in the highest steamed bread score and concentration of volatile compounds. Nitrogen application also intensified soil water use, particularly before anthesis. In 2022–23, the highest N240 reduced soil water at maturity by 16.6% (FS) and 15.9% (DS) and increased total water consumption by up to 7.8% compared to N0. Yield was strongly correlated with soil water depletion in the 0–200 cm layer during the reproductive period. While N240 optimized quality, the N180 rate combined with improved sowing methods (FS or DS) provided the best balance, drill sowing was crucial agronomic practice for enhancing nitrogen-use efficiency (NUE), achieving high yield, superior WUE, and acceptable quality. We therefore recommend an N rate of 180 kg ha−1 with improved sowing as a sustainable practice for dryland wheat production on the Loess Plateau.

[Objective]To clarify the precise management of water and fertilizer based on spring growth stages,and to reveal the mechanism of optimizing yield components through efficient light energy utilization,thereby contributing to the increase in grain yield of winter wheat.[Method]The field experiment was conducted at the TaiGu Winter Wheat Experimental Station in Jinzhong,Shanxi Province,from 2021 to 2023.A split-plot design was adopted,with two spring nitrogen top-dressing rates(90 kg·hm-2,N90;120 kg·hm-2,N120)as main plots,and four top-dressing times after regreening(10 d,20 d,30 d,and 40 d)as sub-plots.Through systematic surveys of tillering dynamics and measurements of canopy photosynthetic active radiation interception,combined with the fitting of the grain-filling process using the Richards model,we systematically analyzed the effects of different nitrogen topdressing treatments on the winter wheat population structure,canopy light distribution,and grain-filling characteristics.Correlation analysis was conducted to clarify the intrinsic relationships among population photosynthetic performance,tillering dynamics,and yield components.[Result]Compared with other treatments,applying 120 kg·hm-2 of nitrogen at 30 days after regreening reduced the peak tiller number,delayed the occurrence of the tillering peak,and decreased the tiller senescence rate by 28%-43%.It also decreased the number of ineffective tillers(50-70 days after regreening)by 15%-30%,thereby significantly increasing the tiller-to-spike ratio by 10%-23%.Significantly increased the canopy PAR interception rate and extinction coefficient during the anthesis and mid-grain-filling stages,while significantly reducing the decline rate of lower-layer PAR interception during the anthesis-to-grain-filling period.Significantly increased the theoretical maximum 1000-grain weight,initial filling potential,average and maximum grain-filling rates,the time to reach maximum grain-filling rate,the duration of the gradual-increasing phase,and the grain-filling rates during the rapid-increasing and slow-increasing phases;significantly increased spike length by 3%-10%,spike weight by 8%-14%,and seed setting rate by 2%-12%.Significantly increased the number of spikes by 4%-10%,the number of grains per spike by 3%-10%,and the 1000-grain weight by 5%-10%,resulting in an increase in grain yield of 7%-20%.The Population Photosynthetic Potential during the booting-anthesis period showed a significant positive correlation with the tiller number at 45-70 days after regreening;meanwhile,the tiller number at 45-70 days after regreening was significantly and positively correlated with the spike number at maturity.The radiation interception rate in the lower layer of the canopy at the mid-grain-filling stage showed a significant positive correlation with the tiller number at 50-55 days after regreening;meanwhile,the tiller number at 50-55 days after regreening was significantly and positively correlated with the number of grains per spike.The PAR interception rate in the canopy at anthesis and mid-grain-filling stages showed a positive correlation with the tiller number at 50-55 days after regreening;meanwhile,the population photosynthetic potential during the booting-anthesis period was significantly and positively correlated with the tiller number at 50-55 days after regreening,and the tiller number at 50-55 days after regreening was significantly and positively correlated with the 1000-grain weight.[Conclusion]Application of 120 kg·hm-2 nitrogen topdressing 30 days after regreening achieved a synergistic improvement in the number of effective spikes,grains per spike,and 1000-grain weight,thereby significantly increasing grain yield.This was realized by suppressing and delaying the tillering peak,optimizing the post-anthesis canopy light distribution,and enhancing the grain-filling process.Furthermore,correlation analysis further confirmed that the population photosynthetic potential before anthesis and the canopy photosynthetic performance after anthesis,by influencing spikelet formation and grain filling,jointly determined the final grain yield.This study provides a critical nitrogen management strategy for achieving high-yield and efficient cultivation of winter wheat in the irrigation area of the Loess Plateau by improving the population photosynthetic efficiency through integrated water and fertilizer management.

Dryland wheat production on the Loess Plateau is constrained by water scarcity and low nitrogen use efficiency. A three-season field experiment (2022–2025) evaluated the combined effects of fallow tillage (subsoiling, SS; no-tillage, NT) and nitrogen rates (0, 90, 135, 180, 225 kg ha⁻¹) in a split-plot design. SS significantly increased soil water storage change during fallow (ΔSWSf) in the 100–200 cm layer by 37.4 mm, leading to a 101.4% increase in post-anthesis deep soil water use. When combined with optimized N (135–180 kg ha−1), SS reduced 0–200 cm nitrate residue compared to NT, whereas excessive N (225 kg ha−1) increased deep leaching risk. SS with optimized N also enhanced post-anthesis flag leaf photosynthesis, nitrogen metabolism enzyme activities, and antioxidant capacity, thereby promoting dry matter and nitrogen accumulation, especially in dry seasons. SS with 180 kg N ha−1 in the wet and normal seasons and 135 kg N ha−1 in the dry season achieved the highest grain yield of 7114, 5699, and 5211 kg ha−1 and water productivity of 13.55, 13.39, and 13.04 kg ha−1 mm−1. SS increased agronomic efficiency, recovery efficiency, and partial factor productivity of N, but these efficiencies declined significantly when N rates exceeded the optimum across all season types. Partial least squares path model identified ΔSWSf as the primary yield driver and flag leaf traits as a key regulator reducing nitrate residue. In conclusion, SS with optimized N rates (135–180 kg ha−1) synergistically improves yield, resource efficiency, and environmental sustainability, but excessive N under wet conditions should be avoided to prevent deep nitrate accumulation.

The ridge-furrow with plastic film mulching (RFM) system has proven effective for improving wheat yields in rain-fed regions. However, its effectiveness in enhancing wheat yield and stability in response to different nitrogen types (NT) has not been thoroughly explored. Furthermore, the mechanisms underlying wheat plant utilization of thermal, radiation, water, and nutrient resources remain poorly understood. To address these issues, a five-season field experiment was conducted in China's Loess Plateau Region, with four planting patterns [traditional flat planting (TP) and three ridge widths of 20 cm (RF20), 40 cm (RF40), and 60 cm (RF60), with a furrow of 40 cm] under two typical NT [normal urea (NU) and slow-release nitrogen fertilizer (SRN)]. The effects of these planting patterns and NTs on soil hydrothermal conditions, crop phenology, grain yield(GY), and the utilization of resources in winter wheat were examined. The results showed that RFM systems, particularly those with broad ridges, superior to TP in terms of improving soil hydrothermal conditions and plant nitrogen nutrition index. In comparison to TP, these modifications greatly improved the RFM system's GY as well as its utilization of water, nutrients, thermal and radiation. As the yield-boosting effect of the RFM system is more noticeable in both dry and normal years, it ensures annual yield stability. Applying SRN enhances the yield of RF40 and RF60 compared to NU, but not in RF20 or TP. However, no significant difference was observed between NTs during extremely dry years (2023-2024). The RF40 planting pattern produces the highest GY regardless of the rainfall year type, with an average yield of 4742.0 kg ha-1. In conclusion, integrating SRN with a 40 cm ridge width in the RFM system optimized resource use efficiency and significantly enhanced rain-fed wheat production on the Loess Plateau.

Background: Quinoa (Chenopodium quinoa Willd.), valued as a nutrient-dense grain, has seen expanded cultivation in China. However, its yield and quality are often unstable due to suboptimal fertilization practices, and the specific regulatory roles of macronutrients (N, P, K) remain unclear. This study aimed to elucidate the effects of combined NPK fertilization on the growth, yield, and nutritional quality of quinoa. Methods: A pot experiment was conducted in a controlled climate chamber using the “Jingli 1” cultivar. Plants were subjected to four fertilization treatments: NPK, PK, NK, and NP. Results: The NPK treatment significantly enhanced growth throughout the development cycle, increasing total root length (45.0±8.5%), root surface area (32.8±6.2%), plant height (20.0±5.0 cm), and dry matter accumulation (71.6±15.3%). It also improved nitrogen use efficiency and key yield components, including panicle length (5.63±1.22 cm), thousand-grain weight (0.34±0.02 g), and grain weight per plant (1.41±0.23 g). Nutritionally, the NPK treatment elevated the content of essential amino acids (284.10±52.75 mg/g), total free amino acids (2414.65±428.30 mg/g), and increased levels of protein, starch, and fat. Deficiency analyses revealed distinct limitations: nitrogen deficiency primarily constrained aboveground growth and yield; phosphorus deficiency strongly inhibited root development and dry matter accumulation; while potassium deficiency had comparatively minor effects. The synergistic application of NPK fertilizers is crucial for optimizing quinoa production. It promotes robust root and shoot growth, enhances nitrogen uptake, and simultaneously achieves high yield and superior nutritional quality, providing a scientific basis for optimized quinoa cultivation practices.

Drought stress inhibits quinoa (Chenopodium quinoa Willd.) seed germination and seedlings growth, significantly affecting yield and quality. Nevertheless, the molecular mechanisms underlying quinoa’s drought stress response are not yet fully elucidated. Therefore, a multi-omics analysis of the response to drought stress was conducted using two drought-resistant quinoa varieties (LL1 and LQ18) subjected to normal (CK) and severe (DS2, 20

The Loess Plateau is a principal dryland winter wheat production region in China, where unreasonable sowing rate and fertilization management limit yield and quality. A two-factor split-plot experiment was conducted during 2019-2021 with three sowing rates (150 kg ha-1, 180 kg ha-1, 210 kg ha-1) and three fertilization type (CK, OPT, OPT-N). Increasing sowing rate to 210 kg ha-1 significantly improved population tiller, secondary root number, and canopy structure. OPT reduced N input by > 50% but maintained plant growth and delayed leaf senescence. The 180 kg ha-1 rate enhanced canopy light interception at anthesis, while 210 kg ha-1 better sustained post-anthesis chlorophyll content, net photosynthetic rate, and stomatal conductance. Compared with OPT, OPT-N markedly restricted root growth, photosynthesis, and matter accumulation. 210 kg ha-1 + OPT significantly increased 1000-grain weight by 5-11%, grain yield by 1.7-3.7%, total starch by 1.91-5.22%, and flour processing quality. The interaction significantly regulated growth, photosynthesis, yield, and quality. This study demonstrates that 210 kg ha-1 + OPT realizes synchronous improvements in yield, quality, and resource efficiency under reduced N input, providing a green cultivation model for dryland wheat.

Quinoa (Chenopodium quinoa Willd.) is a nutritionally valuable and stress-tolerant crop in which seed germination plays a critical role in seedling establishment and yield formation. However, the integrated regulatory mechanisms underlying genotypic variation in germination are not yet fully understood. Most existing studies have focused on phenotypic traits or single-omics approaches, leaving a knowledge gap in systematic analyses that combine seed coat architecture, hormone dynamics, transcriptomics, and gene co-expression networks. Phenotypic analysis showed that WT seeds achieved 100

Salt stress is a major abiotic factor limiting plant growth and productivity. Herpetospermum pedunculosum, a medicinal plant adapted to high-altitude environments, offers a unique non-model system for investigating salt stress responses. Here, we combined physiological and biochemical assays with time-course root transcriptome profiling to characterize the responses of H. pedunculosum to 200 mM NaCl treatment. Salt stress induced rapid wilting, oxidative stress-related physiological changes, membrane damage, and significant accumulation of ABA, total lignin, and total lignans. RNA-seq across five time points (1, 3, 24, 48, and 96 h) identified nearly 28,000 differentially expressed genes (DEGs), which formed distinct temporal clusters associated with hormone signaling, transcriptional regulation, stress responses, and phenylpropanoid-related metabolism. Antioxidant enzyme-related genes, ABA biosynthesis/homeostasis genes, ABA signaling components, and lignin/lignan pathway biosynthesis genes (LLPBGs) showed stage-specific expression patterns, with several genes responding rapidly during the early phase of salt stress. WGCNA and co-expression analyses further identified trait-associated modules and candidate links among core TFs, ABA-related genes, and LLPBGs. Subcellular localization, yeast transactivation, Y1H and Dual-LUC assays provided preliminary evidence that the AP2/ERF factor HpERF141 can bind to and activate the promoter of the previously characterized lignan-related gene HpDIR17. Overall, this study provides a root-focused transcriptomic resource and identifies candidate regulatory genes potentially linking ABA-related responses with lignin/lignan-associated metabolism in H. pedunculosum under salt stress.

Winter wheat covers approximately 2.21 × 108 ha globally, making it the most widely cultivated cereal crop in the world. In recent years, integrated water and fertilizer management has significantly improved winter wheat yield and nitrogen use efficiency; however, quantitative assessments of nitrogen cycling under different fertilizer forms in such high-yield systems remain limited. From 2022 to 2024, a two-year field experiment was conducted in drip-irrigated winter wheat fields in northern China. Four nitrogen fertilizer forms were applied: nitrate nitrogen fertilizer (NON), ammonium nitrogen fertilizer (NHN), amide nitrogen fertilizer (CON), and urea ammonium nitrate fertilizer (UAN), along with an unfertilized control (CK). Compared with NON, NHN, and CON, UAN reduced cumulative N2O emissions by 10.40–15.64% and NH3 volatilization by 2.04–9.33% (p < 0.05). It also increased the leaf area index and biomass accumulation at maturity, as well as grain yield (3.70–10.28%), nitrogen harvest index (4.58–12.88%), and nitrogen use efficiency (12.14–39.25%) (p < 0.05). Furthermore, UAN significantly decreased the net nitrogen surplus (24.18–45.70%) and nitrogen balance values (25.64–55.82%) (p < 0.05). Correlation analysis indicated that the reduction in nitrogen balance was primarily attributed to lower N2O emissions and improved nitrogen use efficiency (p < 0.05). In conclusion, the application of urea ammonium nitrate under integrated water–fertilizer management achieved higher yield, greater efficiency, and environmentally sustainable production in drip-irrigated winter wheat systems in northern China.

The aim of this study was to investigate the effects of different N application rates on the yield, N accumulation, and grain quality of triticale and provide a theoretical basis for selecting the best N application rate for sowing triticale in the loess parent material area. This experiment was conducted at the experimental station of Shanxi Agricultural University in Jinzhong City, Shanxi Province, China, from 2021 to 2023 to study the effects and differences of different N application rates (N application rates 180, 210, 240, 270, and 300 kg ha−1) on the yield formation, N utilization, and quality of the two triticale varieties Donghei10 (DH10) and Taizi6336 (TZ6336). The results showed that, compared with other N application rates, N240 increased the number of spikes and grains per spike of triticale and increased the yield by 6–19%. The yield increased most significantly when the N application range was 210–240 kg ha−1; the yield change rate per 2 kg of N increase was the largest within this range, and the continued increase in yield with increasing N application was slow. N240 also improved the NUE, NUPE, nutritional quality, and processing quality of triticale. The results of the pathway analysis showed that the N application rate affected the spike number, grain number per spike, and 1000-grain weight of triticale. N accumulation at the anthesis and maturity stages affected GS and GOGAT activities in the flag leaf and grain, thus affecting the N efficiency, yield, and protein content. Overall, a N application at 240 kg ha−1 increased the yield, nitrogen efficiency, and quality of triticale, and there was no significant difference in yield between DH10 and TZ6336.

The ideal population type is the basis of high-yield and high-efficiency cultivation of wheat. Population uniformity is an important index to evaluate the population ideotype. Therefore, it is necessary to analyze the yield difference of winter wheat at different spike layers between different populations because spike layer affects the production function of population. Here, two 2-year field experiments were conducted to investigate the effects of irrigation times, nitrogen application rate, and planting density on wheat yield, population traits, sugar and dry matter accumulation, and photosynthetic parameters at different spike layers. The results indicated that optimal planting density (SD3), nitrogen (N2) and irrigation (W1 or W2) deceased the ineffective tillers number at flowering stage and improved the spike number at upper and middle spike layers, which leading to lower coefficient of variation (CV) and higher population uniformity. Increasing planting density, nitrogen, and irrigation promoted high grain yield and population-scale biomass accumulation mainly due to the increment of spike number and yield at upper and middle spike layers. But, the single-stem biomass and grain dry weight reduced with increased planting density whereas improved with an increase of nitrogen and irrigation. Increasing planting density, nitrogen, and irrigation improved the leaf area index (LAI) and light interception at the upper and middle canopy, but decreased it at the lower canopy. Furthermore, the chlorophyll content at flag leaf and penultimate leaf was higher than that of top third leaf. Thus, the single-stem and each organ biomass accumulation, and sugar content gradually decreased from the upper to the lower layers, leading to decreased grains number per spike and average grain weight. Increasing planting density decreased spike length, total soluble sugar content and dry matter accumulation of spike at different spike layers but improved these indicators in stem, which leading to decreases in grain number per spike; whereas these indicators improved with increased irrigation. Overall, these findings provided theoretical and practical basis for building ideal crop population, and breeding and cultivation of winter wheat with high yield.

Continuous cropping of quinoa leads to soil degradation, reduced yield, and crop failure, underscoring the need for sustainable management practices. This study evaluated the effects of winter oilseed rape–quinoa rotation and humic acid (HA) application on quinoa growth, soil enzyme activity, microbial communities, and rhizosphere health under field conditions in Shanxi Province, China. Crop rotation significantly enhanced soil sucrase and urease activity, improved root morphology, increased dry matter accumulation, and enriched beneficial rhizosphere bacteria (e.g., Actinobacteriota, Acidobacteriota, Gemmatimonadota,), while suppressing pathogenic fungi such as Fusarium and Aspergillus. Rotation increased single-spike weight, grain weight, and overall yield by 23.38

As a barrier for plants to contact with the outside world, epicuticular wax plays an important role in resisting biotic and abiotic stresses. To gain a deeper understanding of the molecular mechanism underlying the epicuticular wax increase mutant iew-1, this study compared the transcriptome profile and photosynthetic characteristics of the wild-type and mutant iew-1. Transcriptome profiling screened out 602 differentially expressed genes, of which 403 genes were up-regulated and 199 genes were down-regulated. GO enrichment analysis and KEGG analysis showed that the differential genes were mainly enriched in light harvesting, light reaction, and photosynthesis. These results showed that epicuticular wax may be closely related to photosynthesis. The analysis of photosynthetic characteristics further confirmed that the mutant iew-1 has significantly better photosynthetic capacity than the wild-type, which is consistent with RNA-seq data, indicating that an increase in epicuticular wax can improve the photosynthetic efficiency of wheat. This study provides a solid theoretical basis for exploring the molecular mechanisms and gene regulation of epicuticular wax and photosynthesis.

Rain-fed agroecosystems require integrated strategies to synchronize water and nitrogen use for sustainable production. To investigate the mechanisms by which ridge-furrow planting (RP), coupled with optimal N rate (90, 135, 180 kg N ha-1), enhances soil water utilization, yield formation, and water productivity (WP) in dryland wheat systems, a three-year split-plot field experiment (2018-2021) was designed to compare RP against flat planting (FP) under semi-arid rainfall variability. Results showed that RP improved rainwater infiltration into deeper soil layers, increasing soil water storage by 4.3-8.0 % at jointing and elevating soil water use rate by prioritizing deep-layer extraction during critical growth stages. RP combined with optimized N rates achieved the highest grain yield (25.9 %, 15.3 %, and 10.8 % increases in dry, normal, and wet years) and WP by harmonizing water-N synergies. Enhanced post-anthesis water extraction from 160-200 cm layers under RP significantly boosted dry matter accumulation. Correlation analyses revealed that spike number in dry years correlated with pre-anthesis water use in the 80-160 cm layer (P < 0.01), kernels per spike in normal years aligned with balanced pre-/post-anthesis allocation across 0-200 cm (P < 0.05), and 1000-grain weight in wet years depended on post-anthesis extraction from 160-200 cm (P < 0.01), synergistically driving yield gains. RP integrated with adaptive nitrogen thresholds (90-180 kg ha-1) is recommended to stabilize yields and maximize WP in rain-fed systems. This strategy provides a scalable pathway to strengthen climate resilience and sustainable resource utilization in water-limited agroecosystems.

Drip fertigation (DF) can improve yield, water use efficiency (WUE), and nitrogen use efficiency (NUE, grain production per unit of the sum of soil inherent mineral N and fertilizer N), as well as reduce the risk of environmental pollution compared with flood irrigation and N fertilizer broadcast (FB). Previously, we showed that DF enhanced the response of the yield to the N topdressing rate (NTR), but the underlying mechanisms associated with the soil N supply, root architecture, and N uptake remain unclear. We conducted a field experiment by testing six N treatments (no N applied, and NTRs of 0, 40, 80, 120, and 160 kg ha−1, denoted as N0, T0, T40, T80, T120, and T160, respectively) under DF and FB from 2021 to 2023. Compared with FB, the NUE and WUE were 4.8–4.9% and 10.0–10.5% higher under DF. The higher NUE was due to an improvement in N uptake efficiency (6.1–7.7%) resulting from the enhanced aboveground N uptake (AGN). The greater AGN under DF was attributed to the higher soil N availability at the soil depth of 0–40 cm. DF decreased the residual soil NO3−-N at a depth of 40–200 cm but increased the NO3−-N at a depth of 0–40 cm. In addition, DF combined with T80 achieved high root length density, surface density, and dry weight density and improved NUE and WUE. DF combined with T80 achieved high yield and efficient utilization of water and N, and the NTR threshold was 61.75–119.50 kg ha−1, in which the production conditions were similar to those of the experimental site. Our results provide a reference for high-efficiency water and N fertilizer usage for irrigated winter wheat production in North China.

The application of controlled-release urea or deep fertilization is effective for increasing crop yields. However, more research is needed to determine whether the deep placement of controlled-release and common urea can increase crop productivity and reduce environmental pollution. Between 2019 and 2021, we conducted field experiments in semi-humid and drought prone areas of the Loess Plateau region in China to study the effects of different controlled-release and common urea fertilization methods on maize productivity. Further experiments were conducted in semi-arid areas in 2022 and 2023 to verify the research results. We used the traditional fertilization strategy with common urea (TFC) as the control, deep placement of common urea (DFC), traditional fertilization with controlled-release and common urea (TFB), and deep placement with controlled-release and common urea (DFB) as optimized fertilizer management strategies. The results showed that the deep placement of controlled release and common urea changed the temporal and spatial distributions of the soil NO3--N and NH4+-N, which affected the N2O and NH3 emissions. The NH3 emissions under DFC, TFB, and DFB were lower by 29.78%, 32.77%, and 59.08% than TFC, and N2O emissions were lower by 38.21%, 40.96%, and 72.89%, respectively. Compared with TFC, the maize yields under DFC, TFB, and DFB were 7.91 %, 8.41 %, and 15.11 % higher, respectively, and the nitrogen use efficiencies were 14.23%, 15.60%, and 27.83% higher, whereas the yield-scaled N2O emissions were 38.21 %, 40.96%, and 72.89% lower, and the yield-scaled NH3 emissions were 29.78%, 32.77%, and 59.08% lower. Overall, DFB obtained the highest maize yield (12013.35 kg ha-1) and nitrogen use efficiency (47.15 %), as well as the lowest gaseous nitrogen loss intensity (1.13 g N kg-1 grain), global warming potential (323.08 kg CO2-eq ha-1), and greenhouse gas emission intensity (GHGI, 27.13 g CO2-eq kg-1 grain). Therefore, deep placement of controlled-release and common urea is an effective fertilizer management strategy that can balance maize productivity and environmental pollution in the Loess Plateau region of China.

Quinoa (Chenopodium quinoa Willd.) seedlings are recognized as plant-based foods with high nutritional value, yet they remain scarcely studied. This study aimed to comprehensively evaluate 72 quinoa varieties, harvested 30 days after sowing, by comparing their agronomic and quality traits to spinach (Spinacia oleracea) to identify superior genotypes for use as microgreens or leafy vegetables. Two varieties, JQ-1798 and JQ-2322, were screened out as highly suitable. Sensory analysis revealed that the juice from these seedlings had a less bitter taste, a fresher flavor, and a higher moisture content than spinach. Nutritionally, they were rich in fat, protein, amino acids, and vitamin C. The essential amino acid composition was well-balanced and notably rich in lysine. Furthermore, these varieties contained significantly high levels of functional compounds, including flavonoids, total polyphenols, carotenoids (β-carotene and lycopene), and chlorophyll. Crucially, they exhibited low anti-nutritional factors, with low oxalic acid content and nitrite levels that were below the national safety limit. These results demonstrate that the selected quinoa seedlings have great potential as a highly nutritious and palatable green leafy vegetable.