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Soils with high organic carbon (SOC) have been shown to enhance crop yields while minimizing climate-induced losses. However, the resilience impacts and mechanisms by which high SOC enhances crop performance have not been fully explored. Here, eight-year rotations of winter wheat and summer maize managed with chemical fertilizer input alone (CF) or with cattle manure (OM) or with peat and vermiculite (PV) were conducted, and various soil properties were measured alongside crop growth, nitrogen (N) uptake, and grain yield, with seasons categorized as dry or normal based on precipitation amounts. The OM and PV treatments increased SOC by 57% and 78% relative to the CF, respectively, and improved soil nutrient availability and the soil quality index. Soil moisture content in the 0–30 cm layer increased by 3.5–26.6%, but was less influenced in the 30–90 cm soil layers. Annual yield of wheat plus maize increased by 13% and 12% in OM and PV compared to the CF, and the yield sustainability index increased by 29% and 17%. Yield gains were more pronounced in dry compared to normal seasons, ranging from 19% to 28% and 12–15% for wheat. At least in part, the relative advantages of OM and PV treatments under drying conditions were associated with accelerated growth and N uptake rate from sowing to stem elongation for wheat and maize. Among the factors influencing yield in the present study, soil moisture exerted the greatest positive total effect on yield. Overall, the results highlight that enhanced SOC resulting from combined application of organic amendments and mineral fertilizer was positively associated with yield by promoting soil quality and water availability, with a more pronounced benefit under water-limited conditions. [Display omitted] • Improved soil quality and moisture enhance wheat and maize yield and stability. • Combined inorganic fertilizer and organic amendments increased soil moisture in the 0–30 cm but not in deeper layers. • Better soils with high SOC enhanced wheat and maize yield and stability during dry seasons. • Accelerated vegetative growth and nutrient uptake by high SOC contributed to productivity resilience. [ABSTRACT FROM AUTHOR]

The use of "green manure"—crops that are cultivated specifically to be incorporated into the soil to increase its organic matter content—has been proposed as an alternative to chemical fertilizer because of its benefits in terms of crop yield. Nonetheless, the differential impacts of green manure on ammonia volatilization remains underexplored. In this study, the influence of various green manure management strategies on ammonia volatilization in maize cultivation were examined. Field experiments conducted from 2020 to 2022, the field experiment applied common vetch after the spring wheat harvest, with five distinct treatments: conventional tillage without green manures as a control (CT); tillage with total green manure incorporation (TG); no-tillage with total green manure mulching (NTG); tillage with only root incorporation (T); and no-tillage with removal of aboveground green manure (NT). The results showed that under TG and NTG, the maize yields were 12.3%-33.2% higher than under CT, and 6.8%-18.8% higher than under T and NT. Compared with CT, all four green manure management practices also significantly increased NH 3 emissions in maize fields, and they increased ammonia volatilization by 12.0%-13.7% in NTG and TG compared to root retention patterns, with NTG exhibiting higher rates than TG. NTG significantly increased soil organic matter, total nitrogen, mineral nitrogen, water-filled pore space (WFPS), microbial biomass carbon and nitrogen, and C: N, and it decreased soil pH compared to TG. Regression analysis showed that these factors were correlated with NH 3 volatilization. In addition, soil urease and ammonia-oxidation functional genes (amo A) showed differences under green manure management practices. Structural equation modeling showed that NH 4 +-N had the greatest positive impact on NH 3 , and urease activity and total nitrogen had positive effects on NH 4 +-N. Furthermore, microbial biomass carbon and pH had positive and negative effects on urease activity, respectively, both of which were only related to SOM. At the same time, WFPS had a positive impact on total nitrogen. In summary, no-tillage with total green manure mulching increases maize yield but also increases NH 3 emissions. NH 4 +-N formed by the hydrolysis of urea by soil urease and the conversion of total nitrogen were found to be the main reasons for high NH 3 emissions. In addition, SOM can promote urease activity, increase NH 4 +-N content and NH 3 volatilization by increasing MBC and decreasing soil pH. [Display omitted] • No-tillage combined with total green manure retention can enhance soil quality and crop yield. • NH 3 volatilization is mainly a physicochemical process caused by the control of NH 4 +-N. • Urease activity and total nitrogen have significant effects on NH 4 +-N. • Increasing microbial biomass carbon and decreasing soil pH can promote urease activity. [ABSTRACT FROM AUTHOR]

Evaluating the contribution of diverse nitrogen (N) sources in agricultural systems is pivotal for optimizing sustainable farming practices. While knowledge exists about the roles of various N sources, there's limited comprehensive data on the relative contributions of manure compost, fertilizer, and root residues to subsequent plant uptake. A comprehensive field study was conducted in Shandong Province, China, utilizing 15N labeling techniques to clarify these contributions. Four treatments were established, each incorporating four exogenous nitrogen sources (manure compost + urea + maize root + residual urea) applied concurrently at wheat seeding, with only one source being 15N labeled per treatment. Additional two treatments served as controls, one without 15N labelling and another without manure compost. During a wheat growing season, the N contribution from each individual source to subsequent wheat growth was quantified. Manure contributed 10% of the wheat seed N, while urea contributed 18% and maize root contributed 0.3%. Nitrogen recovery in distinct components of the wheat plant (seeds, straw, and roots) was assessed, revealing urea's superior use efficiency within the total wheat biomass at 55%. In contrast, both manure compost and maize root showed a recovery rate of 29%. Although this study spans only one-year, it offers fresh perspectives on the differential contribution and use efficiency of key N sources under field conditions, emphasizing their role in bolstering crop health and productivity for sustainable agriculture. [Display omitted] • Manure contributes 10% of N in wheat seeds, more than maize root (0.3%), but less than urea (18%). • Soil and other contributes 72% of the seed N, 71% of the straw N, and 65% of the root N. • N use efficiency in wheat biomass is comparable for manure and maize root (29%). • Urea shows superior N use efficiency in wheat total biomass at 55%. • Grains per spike, not spike number or grain weight, influence yield differences. [ABSTRACT FROM AUTHOR]

The current context of food security and global geopolitical crises calls for proactive efforts to seek adaptive strategies for limited resources in agriculture. The production of phosphatic-based fertilisers has caused a substantial depletion of natural phosphorus (P) reserves, raising concerns about price increases due to the growing demand for P. The aim of the study is to assess whether the use of liquid organo-mineral P-complexes can be an adaptive strategy to address the issue of the limited P-fertiliser resource. A complete randomised block design was implemented with three replicates, spanning two contrasting cropping seasons under a Mediterranean climate with reduced tillage and rainfed conditions. The study aimed to assess the response of a durum wheat–maize rotation to various rates of liquid organo-mineral P-complexes (humic-complexed phosphate; HCP) in comparison to granular triple superphosphate (TSP). The evaluation focused on several parameters, including P availability, plant architecture, dry matter accumulation, grain yield and yield components and P use efficiency (PUE) for both durum wheat and maize. The results revealed that applying HCP at a rate of 4 or 8 kg ha−1 increased soil P availability on average by 66% and 144%, respectively, compared to the control (no P-fertilisation), although a significant interaction with the monitoring year emerged. For wheat, applying HCP at a rate of 8 kg ha−1 of P resulted in higher grain yield (+15%), protein content (+0.9%) and P uptake (+48%) than the control on average considering both monitoring years. In the season characterised by favourable rainfall patterns, the application of HCP at 5 or 10 kg ha−1 of P for maize showed similar effects in terms of soil P availability, dry matter accumulation, grain yields and PUE. Conversely, in the season marked by a deficiency in summer precipitation, low PUE for maize was observed for HCP fertilisers, although they remained positive, unlike the case of TSP. Using HCP in conservation agriculture appears promising as an adaptive solution to address P-fertiliser scarcity, especially amid food security challenges and global crises. However, further studies are required to validate these findings in diverse pedo-climatic contexts and cropping systems. • Humic complexed P fertiliser (HCP) enhances soil P availability, especially at 0–10 cm depth. • HCP resulted in a general higher maize and wheat grain yield and crops P efficiency. • HCP is promising in the context of conservation agriculture. [ABSTRACT FROM AUTHOR]

The crop rotation is a farm-scale management choice that dictates agronomic output, ecological impacts, and farm viability. Rotations have become less diverse recently. Re-diversifying may help agricultural systems meet the growing, dynamic demands from society and challenges from climate change. Using a long-term experiment, we tested whether diversified rotations could a) match the productivity (grain yield) of simplified rotations while b) stabilizing productivity against variable weather in the western U.S. Corn Belt. We identified rotation design choices that drive these productivity-stability dynamics. Although more productive rotations were more susceptible to weather (r = 0.63; p < 0.001), this tradeoff was surmountable (p < 0.001): the corn-oat-winter wheat-soybean (Zea mays L., Avena sativa L., Triticum aestivum L., Glycine max (L.) Merr.) rotation was a) no less productive than the highly unstable, corn-soybean rotation (p = 0.11); and b) only marginally less stable than the most stable rotation (p = 0.06). Crop selection and sequencing were critical to this outcome. High productivity was due to a) overyielding of individual crops in diversified rotations that increased with time; b) sequencing to allow higher-yielding winter crops; and c) beneficial crop legacy effects. Stability was highest in rotations that included crops belonging to more weather-niches (r 2 = 0.67; p < 0.001). Surprisingly, these weather-niches groups did not correspond to traditional categories like cool- vs warm-season crops. These results suggest four principles for the design, study, and implementation of diversified grain rotations that are stable under erratic weather and are as productive as current standard practices. • Long-term study of productivity and weather resistance in diversified grain rotations. • Most-productive 4-species rotation matched the locally common corn-soybean rotation. • Most-productive 4-species rotation was as stable as the most stable tested across weather patterns. • Selection and sequencing of crops for overyielding and weather complementarity are critical. • Principles for designing productive, reliable, diverse rotation are proposed. [ABSTRACT FROM AUTHOR]

Mixing crop species in intercrops often results in yield advantages but the underlying processes are not completely understood. Increased resource capture in intercrops, particularly of light and nutrients, has been frequently demonstrated, but there is less information on the effect of intercropping on the photosynthetic capacity of leaves and on the leaf traits related to photosynthesis. Here we determine whether photosynthetic capacity and associated leaf traits are enhanced in intercropped maize (Zea mays L.), a species frequently used in intercrops. We determined leaf photosynthetic capacity (A 1800) and leaf traits of maize leaves in different canopy layers and at different growth stages in relay strip intercrops with spring wheat (Triticum aestivum L.) or faba bean (Vicia faba L.) and in the maize sole crop. We also measured the distribution of photosynthetically active radiation (PAR) in the canopies. Intercropping with wheat or faba bean resulted in larger specific leaf area (SLA; thinner leaves), lower specific leaf nitrogen (SLN), and lower A 1800 of maize leaves during vegetative growth, and differences were larger for maize intercropped with faba bean than wheat, consistent with stronger shading by faba bean than wheat. After the harvest of companion species, maize leaves received more light in the two intercrops than in the sole maize crop, but this did not result in increases in leaf N concentration, SLN, and A 1800. Results indicate that shading and lower leaf N caused by relay intercropping maize with an earlier sown species negatively affected leaf photosynthetic capacity of maize leaves. The yield increase of maize in relay intercrops was not due to a higher leaf photosynthetic capacity. Options for mitigating or overcoming these negative intercropping effects are discussed. • We measured photosynthesis and leaf traits of maize in relay strip intercropping. • Specific leaf area of intercropped maize was increased due to shading. • Leaf nitrogen concentration was decreased in intercrops with faba bean or wheat. • Leaf photosynthetic capacity of intercropped maize was decreased. • Leaf level responses were not responsible for yield increase in intercrops. [ABSTRACT FROM AUTHOR]

Crop lodging, either stem breaking/stem bending or root lodging, is a major concern for farmers worldwide. In the present study, meta-QTLs, ortho-MQTLs and candidate genes related to lodging and its associated traits were identified using 836 of the 1269 known QTLs retrieved from 107 QTL mapping studies published during 1998–2022. The study resulted in the identification of 86 MQTLs with an average confidence interval (CI) of 1.66 cM (4.26-fold reduction) as against a CI of > 7.08 cM in the initial QTLs. Out of 86 MQTLs, a subset of 12 MQTLs demonstrated stability and robustness, earning them the title of breeders' MQTLs. These selections were made based on criteria such as the number of initial QTLs involved, small CI, high LOD scores, and PVE values. Furthermore, leveraging synteny and collinearity facilitated the identification of 10 ortho-MQTLs shared between wheat and maize. Further, in silico expression analysis allowed the detection of 53 significantly expressed candidate genes encoding different proteins/products including the following: F-box protein, GDSL lipase/esterases, SANT/Myb domain transcription factor, pectin esterase inhibitor domain, glycoside hydrolase family, protein kinase domain, zinc finger domain, cytochrome P450, UDP-glucuronosyl/UDP-glucosyltransferase, glycosyltransferase 61 etc. In addition, 26 lodging tolerance genes from Arabidopsis, rice, and maize were also utilized to identify 34 wheat homologues in wheat MQTL regions. Among these, three genes TraesCS2D02G256600 (TaEREB114 -2D) , TraesCS7B02G340100 (TaIRX14- 7B), and TraesCS1B02G347600 (TaGA2ox4- 1B) were prioritized for qRT-PCR-based expression analysis in one lodging-tolerant (i.e., WH-1105) and one lodging-susceptible (i.e., WH-1184) variety. When comparing these two varieties, we found higher relative expression levels of these three genes in the second basal internode at the milky endosperm stage of the lodging-tolerant variety. The MQTLs, ortho-MQTLs, and candidate genes (CGs) identified in this study can be utilized for marker-assisted selection to improve lodging tolerance and enhance our understanding of the molecular basis of lodging tolerance in wheat. [Display omitted] • Eighty-six MQTLs with significantly reduced confidence intervals were identified. • Twelve MQTLs were recommended for breeding programs for improving lodging resistancein wheat. • Ten ortho-MQTLs were identified between the wheat and maize genomes. • Three genes viz., TraesCS1B02G347600, TraesCS2D02G256600, and TraesCS7B02G340100 were validated using qRT-PCR analysis. [ABSTRACT FROM AUTHOR]

At the agro-ecosystem scale, a combination of green manure and chemical nitrogen fertilizer improves crop yield but also exacerbates soil CO 2 emissions. However, it is unclear whether reducing nitrogen by reapplying green manure to fields can achieve high crop yields and improve carbon mitigation. This study aims to investigate the effects and underlying mechanisms of carbon emissions in maize fields under green manure reapplication combined with a reduction in nitrogen. A field experiment comprising five treatments (green manure reapplication combined with traditional nitrogen application (N100), green manure reapplication combined with a reduction in nitrogen of 10% (N90), green manure reapplication combined with a reduction in nitrogen of 20% (N80), green manure reapplication combined with a reduction in nitrogen of 30% (N70), and green manure reapplication combined with a reduction in nitrogen of 40% (N60)) was conducted at an arid oasis region in northwestern China from 2020 to 2022. This study investigated the effects of reducing nitrogen application while reapplying green manure to the field on maize grain yield, soil respiration rate, and carbon emission efficiency (CEE) and analyzed the relationship between soil respiration rate and soil temperature (Ts), soil water content (SWC), and crop biomass accumulation (BA). The N80 treatment significantly reduced soil carbon emissions (CE) but did not reduce maize grain yield, and it showed a significant increase in CEE of 7.7% compared with the N100 treatment. In addition, this system can ensure no reduction in net primary production (NPP), net ecosystem production (NEP), and carbon sequestration (CS) potential compared with N100 and significantly improves the NPP/CE value. Soil temperature and crop biomass significantly correlated with soil respiration, which explained 68.4–72.9% and 84.4–88.8% of the seasonal variation of soil respiration, respectively. However, there was no correlation between soil moisture and soil respiration. Therefore, reducing nitrogen application by 20% while multiple cropping with green manure application after wheat was a suitable nitrogen fertilizer management measure for improving carbon mitigation in arid areas without sacrificing maize yield. The results of this study provide valuable insights into long-term agricultural management strategies for achieving high agricultural production and environmental friendliness. • N80 ensured that maize grain yield does not decrease. • N80 reduced soil carbon emissions and improved carbon emission efficiency. • N80 ensured no reduction in NPP, NEP and Harvest-C. • N80 improved C sequestration and NPP/CE value. • Ts and BA are the main factors influencing carbon emissions. [ABSTRACT FROM AUTHOR]

Cover crops (CCs) are a recognized best management practice to reduce surface water runoff and nutrient loss from agroecosystems. This 4-yr study was conducted in a tile-terraced field to assess the effects of CCs on nutrient loss compared to without CC (no CC) in a corn (Zea mays L.)-soybean (Glycine max L.) rotation. The 3xCCmix (wheat (Triticum aestivum L.), radish (Raphanus raphanistrum subsp. Sativus), and turnip (Brassica rapa subsp. Rapa)) was aerial seeded in soybean at R6 in 2018 and 2020. Cereal rye (Secale cereale) was drill seeded after the corn harvest in 2019 and 2021 (corn-cereal rye-soybean-3xCCmix). Water samples from individual flumes were collected using automated samplers and analyzed for concentrations and loads of nitrate-N (NO 3 -N), total phosphorus (TP), dissolved phosphorus (PO 4 -P), and total suspended solids (TSS). The 3xCCmix and cereal rye had 16% and 12% lower discharge, respectively, than no CC. The 3xCCmix reduced TSS load 50% compared to CC, while cereal rye had no effect. Cover crops reduced NO 3 -N load 20%, 54%, and 68% during the corn, cereal rye, and soybean growing periods, respectively. Over the full rotations, cumulative discharge and nutrient loads were greater during the 2018–20 crop rotation year because of increased precipitation in 2019. The variability in effectiveness of CCs in reducing nutrient losses was likely affected by different climatic and management factors including CC planting and termination dates. This study highlights the benefits of CCs for reducing sediment and nutrient loss over crop rotation, as well as the continued need for enhanced fertilizer management systems to reduce nutrient loss. • On average, CCs reduced NO 3 -N load in discharge by 20%, 54%, and 68% during the corn, cereal rye CC, and soybean seasons, respectively. • The effect of CC on discharge varied with total rainfall and growing season. • Grass cover crops showed potential to reduce sediment losses in runoff. [ABSTRACT FROM AUTHOR]

A 42-day experiment was conducted to investigate the interactive effects of a stimbiotic (STB) and wheat bran (WB) in broiler chickens receiving diets (DT) based on corn or wheat. A total of 960 Cobb 500 male broiler chicks at zero-day old were allocated to 64 pens with 8 treatments, 8 replicates per treatment, and 15 birds per replicate. The treatments were arranged in a randomized complete block design with 2 × 2 × 2 factorial, with the factors as diet (corn-soybean meal or wheat-soybean meal), STB (with or without), and WB (0 or 50 g/kg). Body weight gain (BWG), feed intake (FI), and mortality-corrected FCR data were collected for the starter (d 0–10), grower (d 10–28), and finisher (d 28–42) phases. Ileal digesta and jejunal tissue were collected on d 18 and 42. Data were analyzed as a 2 × 2 × 2 factorial using a mixed model of JMP. There was no significant 3-way interaction for growth performance and expression of nutrient transporters. There was a significant SB × WB for FCR (P < 0.05) in the grower phase. Stimbiotic supplementation and WB inclusion individually improved (P < 0.05) FCR regardless of cereal type, but this effect was not observed when the two were combined. In the overall phase (d 0–42), birds receiving corn-based diets had higher (P < 0.05) FI and BWG than those receiving wheat-based diets. There was a significant 3-way interaction for ileal digestible energy (IDE) (P < 0.05) and N digestibility (ND) on d 18 and 42 (P < 0.05). There was no effect of STB or WB in corn-based diets, whereas WB inclusion decreased IDE in wheat-based diets, but STB supplementation increased IDE with or without WB. In corn-based diets, WB inclusion increased ND, whereas ND was decreased in wheat-based diets. Supplementation with STB had no effect on ND, but STB increased ND in wheat-based diets with and without WB. Ileal DE was greater (P < 0.05) for wheat- than corn-based diets on d 42. Wheat bran inclusion increased ND in corn-based diets whereas, with STB supplementation, there was no difference in ND with or without WB. There was no difference in ND with or without STB or WB in wheat-based diets. There was a significant STB × DT on the expression of GLUT-1 (P < 0.05). In corn-based diets, STB produced an upward expression of GLUT-1, whereas in wheat-based diets, STB supplementation had no effect. On d 42, stimbiotic supplementation produced upward (P < 0.05) expression of SGLT-1. In conclusion, STB supplementation in wheat- or corn-based diets and with WB inclusion improved energy digestibility. On the other hand, WB inclusion in wheat-based diets decreased nutrient digestibility especially on d 18, thus making room for a positive response to STB supplementation in wheat-based diets compared to the marginal response to STB supplementation observed in corn-based diets. [ABSTRACT FROM AUTHOR]