Application of lactic acid bacteria to Elymus nutans silage from the Tibetan Plateau

The study was conducted to investigate the effect of applying a low temperature fermentative strain of Pediococcus pentosaceus Q6 on the fermentation quality of Elymus nutans silage ensiled at different temperatures. Before ensiling of E. nutans, the grasses were treated without inoculation or with inoculation of either the strain of Pediococcus pentosaceus Q6 or a commercial strain P. pentosaceus (APP). The treated grasses were then ensiled at 10, 15 and 25 ℃, respectively. The ensiled grasses were opened on 30, 60 and 90 d after fermentation for laboratory analysis. The results showed that after 60 days of fermentation at 15 ℃, the fermentation quality of the silage inoculated by P. pentosaceus Q6 was obviously better than the control silage or silage inoculated by APP. Inoculation of P. pentosaceus Q6 at ensiling had an effective reduction in silage pH, and also increased the concentration of lactic acid dry matter in ensiled grasses compared to the control silage or silage inoculated by APP. Meanwhile, application of P. pentosaceus Q6 not only increased the count of lactic acid bacteria, but also inhibited the growth of yeasts and molds in the grass silage. Therefore, P. pentosaceus Q6 is a candidate strain that can be used to making silage at low temperature in the Tibetan plateau.