The tillage method and straw returning are the two most important agronomic measures for crop production, but their combined effects on nutrient accumulation and utilization and grain yield in dryland winter wheat (Triticum aestivum L., namely wheat)–summer maize (Zea mays L., namely maize) double-cropping system are still poorly understood. The present study delves into the impact of the tillage method and straw returning on yield and nutrient accumulation and utilization in wheat–maize double-cropping system based on a field split-plot positioning experiment (started in October 2009). Three tillage methods—plowing (PT, 30–35 cm in depth), rotary tillage (RT, 12–15 cm in depth), no-tillage (NT)—and two straw management—zero straw returning (S0) and straw returning (SR)—were assigned to the main plots and subplots, respectively, thus encompassing six distinct treatments of PTS0, PTSR, RTS0, RTSR, NTS0, and NTSR. The grain yield and its components; the nitrogen (N), phosphorus (P), and potassium (K) accumulation at maturity; and the internal efficiency of N, P, and K in wheat and maize from 2018 to 2022 were investigated. The results indicated that in the experimental years, tillage methods and straw management significantly affected wheat, maize, and annual yield. Compared with NT, RT significantly increased wheat yield by 9.5% and maize K accumulation by 5.8%, and PT significantly increased wheat K accumulation by 11.1% and the yield and N, P, and K accumulation of maize by 6.3%, 7.8%, 8.9%, and 5.3%. Compared with RT, PT significantly increased yield and K accumulation in wheat and yield and N and P accumulation in maize. Compared with NTSR, PTSR significantly increased the yield and N, P, and K accumulation in wheat, but it did not affect yield and nutrient accumulation in maize; RTSR significantly increased wheat yield while it significantly decreased yield and N, P, and K accumulation in maize. Compared with RTSR, PTSR significantly increased the yield and N, P, and K accumulation by 4.0%, 19.5%, 19.6%, and 7.0% in wheat, respectively, and 7.5%, 6.1%, 13.3% and 13.6% in maize. Under the same tillage method, compared with S0, SR significantly increased crop yield and N, P, and K accumulation by 2.4–25.4%, 8.5–43.3%, 12.9–37.8%, and 11.0–51.0%, but it significantly reduced wheat K internal efficiency and maize N, P, K internal efficiency. The effectiveness of straw management on crop yield and N, P, and K accumulation was greater than that of tillage methods. Therefore, the combination of plowing tillage with straw returning (PTSR) is an effective tactic to promote crop yield in dryland wheat–maize double-cropping system. This study offered insights for achieving high yield by regulating the accumulation and internal efficiency of plant N, P, and K nutrients in wheat–maize double-cropping system in drought-prone areas and environments similar to the study areas.

Small changes in soil aggregates-associated organic carbon and soil nitrogen (N) can induce huge fluctuations in greenhouse gas emissions and soil fertility. However, there is a knowledge gap regarding the responses to long-term continuous rotation systems, especially in N-fixing and non-N-fixing crop wheat in terms of the distribution of soil aggregates and the storage of soil carbon (C) and N in aggregates in the semiarid calcareous soil of Central China. This information is critical for advancing knowledge on C and N sequestration of soil aggregates in rainfed crop rotation systems. Our aim was to determine which legume (soybean (Glycine max)– or mung bean (Vigna radiata)–wheat (Triticum aestivum) rotation practice is more conducive to the formation of good soil structure and C and N fixation. A 10-year field experiment, including a soybean (Glycine max)–winter wheat (Triticum aestivum) rotation (SWR) with yield increments of 2020 compared to 2010 achieving 18.28% (soybean) and 26.73% (wheat), respectively, and a mung bean (Vigna radiata)–winter wheat rotation (MWR) achieving 32.66% (mung bean) and 27.38% (wheat), as well as farmland fallow, was conducted in Henan Province, China. The soil organic carbon (SOC), N content in the soil, and the soil aggregates were investigated. Legume–wheat rotation cropping enhanced the proportion of the >2 mm soil fractions and reduced the 2 mm aggregate fractions than the MWR. Two legume–winter wheat rotations enhanced the C and N sequestration that varied with soil depths and size fractions of the aggregate. In contrast, the MWR had greater SOC stocks in all fractions of all sizes in the 0–40 cm soil layers. In addition, the greater storage of N in the macro-, micro-, and silt + clay fractions was observed in the 0–30 cm layers; the MWR enhanced the C/N ratios in most of the size aggregates compared with the SWR. The MWR cropping system is more beneficial to the formation of good soil structure and the increasement of C and N reserves in soil. Thus, these findings show that mung bean, in contrast with soybean in the legume–wheat rotation system of a semiarid temperate zone, may offer soil quality improvement.

To clarify the effects of hydrogen peroxide (H₂O₂) seed soaking on the germination and stress resistance of different edible bean seeds, seeds of mung bean (Vigna radiata L. ‘Keda Green No. 2’), cowpea (Vigna unguiculata L. ‘Keda Cowpea No. 1’), and red bean (Vigna umbellata Thunb. ‘Jihong 352’) were soaked in a 50 mmol/L H₂O₂ solution. The study examined the germination and growth-related physiological indices of seeds after soaking. The results showed that hydrogen-peroxide-primed seeds of mung bean (GBH), cowpea (CBH), and red bean (RBH) exhibited significant improvements in germination performance and physiological activity compared with their respective controls (GBCK, CBCK, and RBCK). The results indicated that H₂O₂ soaking significantly improved the germination ability of the seeds, with the germination rate of mung beans, cowpeas, and red beans increasing by 48.89%, 21.11%, and 18.89%, respectively, and the germination percentage increasing by 31.11%, 24.45%, and 17.77%. Additionally, H₂O₂ soaking enhanced the activity of α-amylase, protease, and the antioxidant enzymes peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT); increased the soluble sugar and soluble protein content in the seeds; and reduced the malondialdehyde (MDA) content. The experiment demonstrated that H₂O₂ promotes the germination of mung bean, cowpea, and red bean seeds by influencing antioxidant enzyme activity, the breakdown of storage substances, and the regulation of germination-related substances, thereby improving seedling adaptation to environmental stress. This study aims to improve the germination rate of legume seeds using H₂O₂ treatment, providing a theoretical basis for techniques to enhance seed vigor, especially for seeds that perform poorly in germination under normal conditions.

With the swift progression of the High-Standard Farmland Construction Program in China and worldwide, many dryland wheat fields can be irrigated once during the wheat growth stage (one-off irrigation). However, the combined strategies of one-off irrigation, tillage, and N management for augmenting wheat grain yield and quality are still undeveloped in drought regions. Two-site split–split field experiments were conducted to study the impacts of irrigation, tillage, and N management and their combined effects on grain yield; the contents of protein and protein components; processing quality; and the characteristics of N accumulation and translocation in wheat from a typical dryland wheat production area in China from 2020 to 2022. The irrigation practices (I0, zero irrigation and I1, one-off irrigation), tillage methods (RT, rotary tillage; PT, plowing; and SS, subsoiling) and N management (N0, N120, N180, and N240) were applied to the main plots, subplots and sub-subplots, respectively. The experimental sites, experimental years, irrigation practices, tillage methods, and N management methods and their interaction significantly affected the yield, quality, and plant N characteristics of wheat in most cases. Compared to zero irrigation, one-off irrigation significantly increased the plant N accumulation, enhancing grain yield by 33.7% while decreasing the contents of total protein, albumin, globulin, gliadin, and glutenin by 4.4%, 6.4%, 8.0%, 12.2%, and 10.0%, respectively. It also decreased the wet gluten content, stability time, sedimentation value, extensibility by 4.1%, 10.7%, 9.7%, and 5.5%, respectively, averaged across sites and years. Subsoiling simultaneously enhanced the aforementioned indicators compared to rotary tillage and plowing in most sites and years. With the increase in N rates, wheat yield firstly increased and then decreased under zero irrigation combined with rotary tillage, while it gradually increased when one-off irrigation was combined with subsoiling; however, the contents of total protein and protein components and the quality tended to increase firstly and then stabilize regardless of irrigation practices and tillage methods. The correlations of yield and quality indicators with plant N characteristics were negative when using distinct irrigation practices and tillage methods, while they were positive under varying N management. The decrease in wheat quality induced by one-off irrigation could be alleviated by optimizing N management. I1STN180 exhibited higher yield, plant N accumulation and translocation, and better quality in most cases; thus, all metrics of wheat quality were significantly increased, with a yield enhancement of 50.3% compared to I0RTN180. Therefore, one-off irrigation with subsoiling and an N rate of 180 kg ha⁻¹ is an optimal strategy for high yield, high protein, and high quality in dryland wheat production systems where one-off irrigation is assured.

Minor legume crops, including mung bean (Vigna radiata), cowpea, and adzuki bean, are crucial for global food security and sustainable agriculture, yet their genetic improvement has been hindered by narrow germplasm resources and lagging breeding technologies. This article systematically reviews the strategy of integrating polyploid breeding with mutagenic breeding as an innovative pathway to overcome the genetic bottlenecks of minor legumes. It focuses on insights gained from model plants and major legume crops like soybean and alfalfa regarding polyploid advantages and efficient mutagenesis techniques. Furthermore, it provides an in-depth analysis of the unique challenges and adaptation barriers encountered when transferring these paradigms to minor crops. Using mung bean as a representative case study, this review highlights specific challenges, including the creation of stable polyploid germplasm, the elucidation of complex regulatory mechanisms in polyploid genomes, and the technical bottlenecks in gene mapping and functional validation. The review also outlines future directions involving the integration of cutting-edge technologies—such as multi-omics, high-throughput phenomics, and gene editing—to establish a holistic research framework of “germplasm innovation-gene mapping-designer breeding”. This integrated approach aims to advance the breeding practices of minor legumes into a new era of precision design.