玉米秸秆低温降解复合菌的筛选及其菌种组成  

Screening and composition of the microbial consortium with corn straw decomposition under low temperature

作　　者：张鑫[1] 青格尔[1,2] 高聚林 于晓芳[1,2] 胡树平 张必周[1] 韩升才 冯彪 ZHANG Xin;Qinggeer;GAO Julin;YU Xiaofang;HU Shuping;ZHANG Bizhou;HAN Shengcai;FENG Biao(Agricultural College,Inner Mongolia Agricultural University,Hohhot 010019,China;Key Laboratory of Crop Cultivation and Genetic Improvement in Inner Mongolia Autonomous Region,Hohhot 010019,China;Horticulture and Plant Protection College,Inner Mongolia Agricultural University,Hohhot 010019,China;Vocational and Technical College,Inner Mongolia Agricultural University,Baotou 014100,China)

机构地区：[1]内蒙古农业大学农学院,呼和浩特010019 [2]内蒙古自治区作物栽培与遗传改良重点实验室,呼和浩特010019 [3]内蒙古农业大学园艺与植保学院,呼和浩特010019 [4]内蒙古农业大学职业技术学院,包头014100

出　　处：《农业环境科学学报》2021年第7期1565-1574,共10页Journal of Agro-Environment Science

基　　金：国家自然科学基金项目(32060434,31760353);国家重点研发计划项目(2017YFD0300804,2018YFD0300401);内蒙古自然基金项目(2020MS03086,2018ZD02);国家玉米产业技术体系项目(CARS-02-63);农业部华北黄土高原地区作物栽培科学观测实验站项目(25204120)。

摘　　要：为筛选适用于北方高寒区玉米秸秆低温降解的复合菌系,促进还田玉米秸秆原位腐解,本研究以内蒙古不同地区采集的57份菌源样品为材料,采用富集培养方法和以玉米秸秆为碳源的低温(15℃)继代培养技术,以不同培养代数秸秆降解率和酶活性为筛选指标,选择高效降解玉米秸秆的复合菌系,并明确其玉米秸秆降解特性及菌种组成多样性。结果表明:57份菌源材料经多层次递进式筛选后获得3个玉米秸秆低温高效降解复合菌系,编号分别为M44、M14和M2,15℃培养20 d后,玉米秸秆降解率分别为35.33%、33.34%和31.33%。其中M44的玉米秸秆降解率较对照(GF-20)高12.25%,秸秆组分中半纤维素和木质素降解率分别较对照高5.47%和23.13%;滤纸酶、内切葡聚糖酶、木聚糖酶和漆酶的活性较对照分别高7.41%、1.44%、13.85%和17.88%。由高通量测序可知,Proteobacteria、Firmicutes和Bacteroidetes为各菌系中的优势菌门,M44中的优势属为Trichococcus、Acinetobacter;M14主要由Azospirillum、Enterococcus组成;M2主要由Delftia、Sphingobacterium组成。综上所述,以玉米秸秆为碳源筛选获得的复合菌系M44在低温(15℃)条件下具有高效降解玉米秸秆的能力。To promote in-situ corn straw decomposition in cold northern regions,this study screened the microbial consortium with corn straw degradation under low temperatures.Fifty-seven bacterial source samples from different areas of Inner Mongolia were selected as screening objects by enrichment culture in a low temperature(15℃)subculture with corn straw as the carbon source,and using the straw degradation rate and enzyme activity of different cultures as screening indexes.The compound strains with high efficiency in degrading corn straw were selected.The degradation characteristics and microbial community diversity of complex strains were determined.The results showed that three complex strains,numbered M44,M14,and M2,with corn straw degradation under low temperature were screened from the 57 materials using the multi-level progressive method.The corn straw degradation rates of M44,M14,and M2 were 35.33%,33.34%,and 31.33%at 15℃for 20 d,respectively.Among the corn straw degradation rates,that of M44 was 12.25%higher than that of the control(GF-20);the hemicellulose and lignin degradation rates of straw were 5.47%and 23.13%higher than those of the control,respectively.The activities of filter paper enzyme,endoglucanase,xylanase,and laccase were 7.41%,1.44%,13.85%,and 17.88%higher than those of the control,respectively.High-throughput sequencing revealed that Proteobacteria,Firmicutes,and Bacteroidetes were the dominant phyla in all consortia.M44 and M14 were predominantly composed of Trichococcus,Acinetobacte,Azospirillum,and Enterococcus.M2 was mainly composed of Delftia and Sphingobacterium.From this analysis,it is conclude that the compound strain M44 obtained using corn straw as a carbon source can effectively degrade corn stalks at low temperatures(15℃).

关 键 词：低温 玉米秸秆 复合菌系 降解特性 菌种组成 

分 类 号：X172[环境科学与工程—环境科学] X71