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

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

doi:10.3389/fmicb.2022.1052837

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

Front Microbiol. 2022 Nov 1:13:1052837. doi: 10.3389/fmicb.2022.1052837. eCollection 2022.

Authors

Meirong Zhao¹, Hongyu Zhang¹, Gang Pan¹, Hang Yin¹, Juanjuan Sun², Zhu Yu³, Chunsheng Bai¹, Yanlin Xue^{4

5}

Affiliations

¹ College of Horticulture, Shenyang Agricultural University, Shenyang, China.
² Institute of Grassland Research, Chinese Academy of Agricultural Sciences, Hohhot, China.
³ College of Grassland Science and Technology, China Agricultural University, Beijing, China.
⁴ Inner Mongolia Engineering Research Center of Development and Utilization of Microbial Resources in Silage, Inner Mongolia Academy of Agriculture and Animal Husbandry Science, Hohhot, China.
⁵ Inner Mongolia Key Laboratory of Microbial Ecology of Silage, Inner Mongolia Academy of Agriculture and Animal Husbandry Science, Hohhot, China.

Abstract

This study aims to investigate the effects of adding Lactobacillus buchneri (LB), Lactobacillus brevis (LBR) and Bacillus subtilis (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 (p < 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 N₂O at 3-7 days of ensiling (p < 0.05), and LBR and BS increased the release of N₂O at 1-40 days of ensiling (p < 0.05). On the first day of ensiling, all silages were dominated by Weisslla, over 3 days of ensiling all silages were dominated by Lactobacillus. Acinetobacter, Serratia, Aquabacterium, and unclassified_f_enterobacteriaceae showed significant negative correlations with nitrate degradation during sorghum-sudangrass ensiling (p < 0.05). The BS and LBR groups increased the metabolic abundance of denitrification, dissimilatory nitrate reduction, and assimilatory nitrate reduction (p < 0.05). Overall, the additive ensures the fermentation quality of sorghum-sudangrass silage and promotes the degradation of nitrate by altering the bacterial community.

Keywords: Bacillus subtilis; Lactobacillus brevis; Lactobacillus buchneri; fermentation quality; nitrate; sorghum-sudangrass silage.