Bioscience Methods 2025, Vol.16, No.5, 254-261 http://bioscipublisher.com/index.php/bm 256 surface, releasing some substances to suppress weeds. Compared with the traditional practice of not planting green manure, it can significantly reduce the number of weeds (Odhiambo et al., 2010). As for pests and diseases, green manure can improve the soil environment and make crops more resistant. However, the specific method of pest control depends on the types of local pests and diseases and crop rotation conditions. In general, as long as the green manure is allowed to grow as long as possible and the decomposition time is controlled to be consistent with the fertilizer requirement period of the crop, the integrated management can be best achieved. 4 Impacts on Legume Growth and Yield 4.1 Emergence, nodulation activity, and physiological traits The use of green manures, especially leguminous green manures, in bean rotation can help beans grow better in the early stage. Green manures such as Sesbania rostrata not only promote nodulation of bean roots, but also improve nitrogen fixation ability, making it easier for plants to absorb nitrogen and accumulate dry matter (Winarni et al., 2016). Green manures can also increase organic matter and nutrients in the soil, which is also helpful for the emergence and initial growth of beans (Shrestha et al., 2025). 4.2 Pod number, 100-seed weight, and biomass changes Green manures can also increase the yield of beans, mainly manifested in more pods, heavier seeds, and stronger plants. Studies have found that using green manure with some trace elements (such as zinc) is more effective than using chemical fertilizers alone. For example, the number of pods, grain weight and biomass of mung beans can be increased by up to 46% (Muindi et al., 2020). Green manure has similar effects in rice or corn fields. It is better than using chemical fertilizers alone or no fertilizer, and can significantly increase dry matter and grain weight (Latt et al., 2009). 4.3 Yield stability under varying substitution levels of chemical fertilizer Green manure can partially or even completely replace chemical fertilizers while ensuring that the yield does not decrease. Many field trials and data analyses have shown that the application of green manure increases yield by 12% to 22% compared with unused plots, among which the most obvious effect is the application of 2 000 to 4 000 kg of dry weight of green manure per hectare (Liang et al., 2022). In corn and wheat fields, green manure not only increases yields, but also improves the efficiency of nitrogen and phosphorus use, reducing dependence on chemical fertilizers. In pastures, growing legumes and grasses together and adding manure can also stabilize yields while reducing the amount of chemical fertilizers used (Oyharçabal et al., 2024). 5 Effects on Soil Properties and Microbial Community 5.1 Increases in organic matter, total N, available P and K Green manure can make the soil more fertile. Whether it is leguminous green manure or other green manure, it will increase the organic matter, total nitrogen and available phosphorus in the soil. Studies have found that compared with fallow or growing only one crop, soil organic matter can be increased by more than 30% and total nitrogen can be increased by about 35% after applying green manure (Dong et al., 2021). In addition, the content of available potassium and microbial carbon in the soil has also increased significantly, up to about 70% of the original. These changes are mainly due to the fact that green manure provides nutrients after decomposition and makes microorganisms more active (Figure 1) (Xu et al., 2023). 5.2 Improvement of soil aggregation and moisture retention Green manure can also improve the structure of the soil. After applying green manure, the larger "aggregates" in the soil will become more numerous and more stable. For example, the number of aggregates with a diameter greater than 0.25 mm can more than double, making the soil more solid and less likely to be washed away (Bai et al., 2022). Green manure can also make it easier for the soil to retain moisture, and plants can grow more easily during droughts or rainy periods. 5.3 Shifts in microbial diversity and functional groups After using green manure, the types of microorganisms in the soil will change. The number of bacteria usually increases, especially when green manure is used with organic fertilizers. The changes in fungi depend on the type of green manure used (Walker et al., 2022). Green manure can also increase the number of "good bacteria", such
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