Biomass Yield And Fermentation Quality Of Silage Corn And Soybean Grown In Strip Intercropping System

Through the experiments of"Effects of silage corn and soybean strip intercropping on biological yield"and"Study on the quality and fermentation mechanism of silage corn and soybean strip intercropping"conducted in 2018-2019,the patterns of strip intercropping of silage corn and soybean were studied.The biological yield effect and the mixed silage fermentation mechanism clarified the suitable row ratio of strip intercropping of silage corn and soybean,and explored the effect of the microbial community structure of corn and soybean mixed silage on fermentation quality.The main results were as follows:1.The biomass yield of silage corn and soybean intercropping treatment was significantly higher than that of monocropping corn and monocropping soybean（P<0.05）.The fresh weight of the intercropping treatment decreases with the increase of soybean rows,and the land equivalent ratio is greater than 1.60,which had a significant compound yield advantage.The biomass yield is the highest when the silage corn and soybean intercropping ratio is 2:3.2.The water-soluble carbohydrates（WSC）of silage corn and soybean strip intercropping fresh materials were higher than that of monocropping soybean,and its crude protein（CP）content is higher than that of monocropping corn.After 60 days of ensiling,the CP content of intercropping mixed silage treatment can be increased by more than 14.91%compared with mono corn silage;compared with mono soybean silage,mixed silage increased the lactic acid content and reduced NH₃-N/TN.The best silage quality was obtained when the row ratio between silage corn and soybean was 2:3.3.Compared with monocropping corn and soybean silage alone,more epiphytic lactic acid bacteria were detected in the mixed silage fresh materials of corn and soybean.During the ensiling,Weissella and Lactobacillus dominated the silage,and the relative abundance of Lactobacillus in the mixed silage was higher than that of soybean silage of the same soybean variety.At 60 days of ensiling and 7 days of aerobic exposure,low relative abundance bacteria such as Pseudomonas,Gluconacetobacter and Oceanobacillus cooperatively affected pH and NH₃-N/TN,which in turn affects fermentation quality.In summary,the strip intercropping of silage corn and soybean is beneficial to increase the total biomass yield,improve the land use efficiency.The larger number of epiphytic lactic acid bacteria of strip intercropping materials are more conducive to its domination in ensiling,inhibiting the growth of undesirable microorganisms,improving the fermentation quality of silage,and making it easier to obtain high-protein,high-quality silage.