Altering bacterial community: A possible way of lactic acid bacteria inoculants reducing CO2 production and nutrient loss during fermentation

• CO 2 production during ensiling with or without additives were investigated. • CO 2 production was closely correlated with the bacterial communities. • L. plantarum could reduce CO 2 production by altering bacterial communities. CO 2 production during ensiling is a source of greenhouse gases emissions and a cause of nutrient loss of silage. To investigate the influence of additives on CO 2 production and relevant bacterial communities, stylo and rice straw were ensiled with sucrose and Lactobacillus plantarum (LP). After 30 days fermentation, LP reduced CO 2 production (from 66.2 to 0 mL/100 g fresh matter in stylo, from 83.7 to 16.6 mL/100 g fresh matter in rice straw) and weight loss (from 2.71 to 1.72% in stylo, from 2.75 to 2.40% in rice straw). CO 2 production was positively correlated ( P < 0.05) with Lactococcus (0.99), Leuconostoc (0.55), Lachnoclostridium (0.45), Prevotella (0.23) and was negatively correlated ( P < 0.05) with Serratia (-0.66), Sphingobacterium (-0.58), Pediococcus (-0.36). LP decreased the relative abundance of genera positively correlated with CO 2 production and increased that of genera negatively correlated. In conclusion, LP could reduce CO 2 production by altering bacterial community during ensiling.