Effects of Lactic Acid Bacteria from Pickles on the Silage Fermentation and Bacterial Community and Anerobic Stability of Maize, Soybean and Their Mixture in Karst Regions

This study aims to investigate the effects of three lactic acid bacteria (LAB) strains, <i>Lactiplantibacillus plantarum</i>, <i>Lactiplantibacillus pentosus</i> and <i>Limosilactobacillus fermentum</i>, isolated from traditional pickles in Guizhou, on the fermentation process and microbial community dynamics of ensiled whole-plant maize, soybean, and their mixtures. The results revealed that compared to the CK group, the lactic acid levels of <i>Lactiplantibacillus plantarum</i> and <i>Lactiplantibacillus pentosus</i> were significantly increased in the treatment groups (<i>p</i> < 0.05), resulting in a faster pH reduction, along with decreases in ammonia nitrogen (AN) and butyric acid (BA) content. In contrast, the <i>Limosilactobacillus fermentum</i> treatment (<i>p</i> < 0.05) promoted acetic acid (AA) production and inhibited the growth of harmful microbiota in soybean silage. Notably, inoculation with all LAB strains enhanced the aerobic stability of maize silage by promoting the proliferation of <i>Lactiplantibacillus</i> during the later stages of fermentation, thereby sustaining a low pH and mitigating the depletion of water-soluble carbohydrates (WSC). Furthermore, all treatments accelerated silage fermentation by enhancing the LAB population and competing with yeast and <i>Escherichia coli</i> for available nutrients in mixed silage. These findings indicate that three LAB strains, when used as microbial additives, demonstrated potential to improve silage quality in the Karst region.