关键词: 玉米秸秆, 青贮, 乳酸菌, 有氧稳定性

Abstract: [Objective] To screen the composite lactic acid bacteria strains for preparation of corn straw storage. [Method] The homofermentative lactic acid bacteria AS06 strain and the heterofermentative lactic acid bacteria BS26 strain obtained in previous study were used as experimental materials to perform corn straw silage fermentation test. Four different treatments of lactic acid bacteria addition were set, including the control treatment group （CK group）, the AS06 strain fermentation treatment group （LP group）, BS26 strain fermentation treatment group （LB group） and mixed fermentation treatment group （LBP group） with AS06 strain and BS26 strain. The pH value, microbial flora, contents of lactic acid, organic acid and soluble carbohydrates （WSC）, and aerobic stability duration of the fermented corn straw silage in different groups after oxygen exposure were determined and assessed. [Result] The corn straw fermented with BS26 strain （LB group） or composite lactic acid bacteria of AS06 strain and BS26 strain （LBP group） had slowly increased pH value and slowly reduced lactic acid content after oxygen exposure. Furthermore, in both of the above fermentation products, the nutritional loss of WSC was effectively reduced, the growth of yeast and mold was significantly inhibited, and the aerobic stability duration reached up to 208 h （LB group） and 147 h （LBP group）, respectively. [Conclusion] Addition of heterofermentative lactic acid bacteria alone or in combination with homofermentative lactic acid can effectively suppress the aerobic corruption during fermentation of corn straw silage, and the former performed better in aerobic stability.

Key words: corn straw, silage, lactic acid bacteria, aerobic stability