添加蔗糖对苜蓿青贮中古生菌和甲烷产生菌群的影响  

Effects of Sucrose Addition on the Archaeal and Methanogenic Bacterial Communities in Alfalfa Silage

作　　者：李荣荣 胡明 魏睿 LI Rongrong;HU Ming;WEI Rui(College of Environment and Life Sciences,Weinan Normal University,Weinan 714000,China)

机构地区：[1]渭南师范学院环境与生命科学学院,陕西渭南714000

出　　处：《中国草地学报》2024年第5期142-148,共7页Chinese Journal of Grassland

基　　金：渭南师范学院人才项目(2022RC24)资助。

摘　　要：采用宏基因组测序技术研究了不添加蔗糖(对照)和添加2%蔗糖对高水分紫花苜蓿青贮中古生菌和甲烷产生菌群的影响。结果表明:对照发酵品质较差,添加蔗糖显著增加了乳酸含量(P<0.05),改善青贮品质。氨氧化古菌是苜蓿原料上最丰富的古生菌种,马氏甲烷八叠球菌和氨氧化古菌分别是对照和蔗糖处理的优势种。基因phnJ是苜蓿青贮中甲烷合成的功能基因。大肠杆菌和肺炎杆菌是对照和蔗糖处理中的优势产甲烷菌,蔗糖添加显著降低肺炎杆菌的相对丰度。马氏甲烷八叠球菌相对丰度与丁酸和氨态氮的含量呈正相关。综上所述,马氏甲烷八叠球菌主导青贮中古生菌群,肠杆菌科细菌是苜蓿青贮中潜在的优势甲烷产生菌,蔗糖处理在一定程度上抑制马氏甲烷八叠球菌和肠杆菌科细菌的繁殖,显著改善高水分苜蓿青贮发酵品质。Metagenomic sequencing was employed to investigate the impact of 2%sucrose supplementation on the diversity of archaeal and methanogenic bacterial communities in high-moisture alfalfa silage compared to a control group without sucrose addition.The results showed that the control group had inferior fermentation quality,while sucrose addition significantly increased lactate content(P<0.05)and improved overall fermentation quality.Nitrososphaera gargensis was the most abundant archaeal species on the raw alfalfa material.Methanosarcina mazei emerged as the dominant archaeal species in the control group,while N.gargensis became dominant species in the sucrose-treated group.The phnJ gene was identified as a putative functional marker for methane synthesis in alfalfa silage.Notably,Escherichia coli and Klebsiella pneumoniae were identified as the dominant methanogenic bacteria in both treatments.However,sucrose addition significantly reduced the relative abundance of K.pneumoniae.Interestingly,a positive correlation was observed between the relative abundance of M.mazei and the levels of butyric acid and ammonia nitrogen.In conclusion,our findings suggest that M.mazei dominates the archaeal community in alfalfa silage,while Enterobacteriaceae family members likely represent the primary methanogenic bacteria.Sucrose supplementation appears to partially inhibit the proliferation of both M.mazei and Enterobacteriaceae bacteria,leading to a significant improvement in the fermentation quality of high-moisture alfalfa silage.

关 键 词：苜蓿青贮 蔗糖 古生菌群 甲烷产生菌 宏基因组 

分 类 号：S816.53[农业科学—饲料科学]