AUTHOR=Zhao Meirong , Zhang Hongyu , Pan Gang , Yin Hang , Sun Juanjuan , Yu Zhu , Bai Chunsheng , Xue Yanlin 

TITLE=Effect of exogenous microorganisms on the fermentation quality, nitrate degradation and bacterial community of sorghum-sudangrass silage

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.1052837

DOI=10.3389/fmicb.2022.1052837

ISSN=1664-302X

ABSTRACT=<p>This study aims to investigate the effects of adding <italic>Lactobacillus buchneri</italic> (LB), <italic>Lactobacillus brevis</italic> (LBR) and <italic>Bacillus subtilis</italic> (BS) on the fermentation quality, nitrate degradation and bacterial community of sorghum-sudangrass silage. The results showed that the addition of LB significantly increased the pH and acetic acid content (<italic>p</italic> &lt; 0.05), but high-quality silage was obtained. The addition of LBR and BS improved the fermentation quality of sorghum-sudangrass silage. The use of additives reduced the nitrate content in sorghum-sudangrass silage. The LB group increased the release of N<sub>2</sub>O at 3–7 days of ensiling (<italic>p</italic> &lt; 0.05), and LBR and BS increased the release of N<sub>2</sub>O at 1–40 days of ensiling (<italic>p</italic> &lt; 0.05). On the first day of ensiling, all silages were dominated by <italic>Weisslla</italic>, over 3 days of ensiling all silages were dominated by <italic>Lactobacillus</italic>. <italic>Acinetobacter</italic>, <italic>Serratia</italic>, <italic>Aquabacterium,</italic> and <italic>unclassified_f_enterobacteriaceae</italic> showed significant negative correlations with nitrate degradation during sorghum-sudangrass ensiling (<italic>p</italic> &lt; 0.05). The BS and LBR groups increased the metabolic abundance of denitrification, dissimilatory nitrate reduction, and assimilatory nitrate reduction (<italic>p</italic> &lt; 0.05). Overall, the additive ensures the fermentation quality of sorghum-sudangrass silage and promotes the degradation of nitrate by altering the bacterial community.</p>