藜麦(Chenopodium quinoa)内生菌LMJB-14的鉴定与生防促生功能研究

Study on the Identification,Biocontrol and Growth-Promoting Function of Endophytic Strain LMJB-14 from Chenopodium quinoa

采用平板对峙法,从藜麦内生菌中筛选出对链格孢属(Alternaria sp.)、镰孢菌属(Fusarium sp.)、刺盘孢属(Colletotrichum sp.)3种常见植物真菌性病害具有较强拮抗作用的细菌,通过菌悬液浸种实验测定其对藜麦种子的促生效果,结合形态学特征、生理生化特征、基因测序分析以确定其分类学地位。结果表明:细菌LMJB-14对3种常见植物病原真菌具有不同程度的拮抗效果,其中对刺盘孢属病原菌拮抗效果最好(抑菌率为31.2%),其次为镰孢菌属病原菌(抑菌率为23.2%),对链格铇属病原菌抑菌率最低(19.2%);以菌株LMJB-14菌悬液浸种对藜麦种子萌发具有促进作用;经鉴定该拮抗菌株为贝莱斯芽孢杆菌。

Aiming at three common plant pathogenic fungi,Alternaria sp.,Fusarium sp.,and Colletotrichum sp.,the antagonistic bacteria were screened from the endophytic bacteria of Chenopodium quinoa by plate confrontation method.The growth-promoting effect of bacteria on quinoa seeds is determined by suspension soaking experiment,and their taxonomic status was determined by morphological,physiological and biochemical characteristics and gene sequencing analysis.The results show that bacterial LMJB-14 had antagonistic effects on three common plant pathogenic fungi in varying degrees,among which the antagonistic effect against Colletotrichum sp.is the best,with an inhibition rate of 31.2%,followed by Fusarium sp.with an inhibition rate of 23.2%and 19.2%against Alternaria sp.Soaking seeds with strain LMJB-14 suspension can promote the germination of quinoa seeds.The antagonistic strain is identified as Bacillus velezensis.