Objective This paper aims to study the effect of adding different proportions of maize starch on the nutrient composition, fermentation quality, aerobic stability and microbial flora of grape branch and leaves silage.

Methods This experiment used a one-factor test design, adding 0% (ck), 2%, 3%, and 4% corn starch for 4 treatments, each treatment with three replicates. The nutrients, fermentation quality, aerobic stability, and microbial flora were determined after 90 days of silage.

Results The CP of 3% added group was significantly higher than those of other added groups (P <0.05), the content of NDF and ADF was lower than those of other added groups, and the difference in EE, Ca and P content was not significant (P> 0.05); pH value, NH₃-N, and AA in 3% added group were significantly lower than 0%, 2%, and 4% added groups (P <0.05), and their LA and WSC were significantly higher than those of 0%, 2%, and 4% added groups (P <0.05); After 7 days of aerobic exposure, the nutrient composition in the 3% added group changed not significantly, and the fermentation quality was slightly better than those in the other groups, with the best aerobic stability; The 3% added group had the highest abundance of Firmicutes and Proteobacteria at the phylum level, and the highest abundance of Lactobacillus bursoni at the genus level, but the 3% added group was higher than that of the 0% added control group.

Conclusion The 3% added group is beneficial to preserve the nutrients, improve the silage quality of grape branches and leaves, enhance the aerobic stability of grape branches and leaves, thus obtaining high-quality grape branches and leaves silage.