Synergistic benefits of leguminous green manure intercropping for weed control and productivity improvement in pear orchards

• LGMs effectively suppress weed growth through high biomass production. • LGM intercropping in pear orchards enhances soil nutrient availability and efficiency. • LGM significantly boosts both fruit yield and quality in pear orchards. • Green manure growth shows a strong correlation with overall orchard productivity. • LGM intercropping provides a synergistic benefit, improving both weed control and orchard productivity. Intercropping leguminous green manure (LGM) in orchards provides a sustainable solution for ecological weed control. LGMs are known to improve soil fertility and productivity in cropping systems. However, the synergistic effect between weed control and productivity improvement in orchards intercropped with LGM remains uncertain. In this study, we selected four LGM species—smooth vetch (SV), hairy vetch (HV), common vetch (CV), grass vetch (GV)—along with a non-legume (NLM), february orchid (FO), in a pear orchard. The control treatment had no plant green manure. Our results showed that green manure was effective in reducing weed density and dry weight, with the effect of LGM on weed control outperforming that of the NLM. Notably, weed dry weight in the HV treatment was reduced by 94.6 % at bloom stage compared to control. SV, HV, and CV treatments significantly increased soil nutrients, including organic matter and nitrogen. The FO treatment significantly increased soil organic matter and total nitrogen compared to the control. HV treatment resulted in the highest fruit yield among the six treatments. Fruit soluble solids were 14.4 % higher, and titratable acid was 34.5 % lower in the HV treatment compared to the control. Additionally, fruit total soluble sugar content was 30.2 % higher in the SV treatment compared with control. The mantel test further confirmed a strong correlation between weed control and enhanced fruit yield, demonstrating the dual benefits of LGM intercropping. These findings support the use of LGM as an effective and eco-friendly management practice for optimizing pear orchard productivity while controlling weeds.