一种新发生的玉米细菌性叶腐病病原菌分离鉴定  

Isolation and identification of pathogen of a new maize bacterial leaf rot

作　　者：王春明[1] 郭成[1] 周天旺[1] 洪流[1] WANG Chunming;GUO Cheng;ZHOU Tianwang;HONG Liu(Institute of Plant Protection,Gansu Academy of Agricultural Sciences,Lanzhou 730070,China)

机构地区：[1]甘肃省农业科学院植物保护研究所,兰州730070

出　　处：《植物保护》2023年第4期256-262,共7页Plant Protection

基　　金：甘肃省科技计划(20JR5RA108);嘉峪关市科技计划(20-17)。

摘　　要：为了明确一种引起玉米叶片腐烂的细菌性病害的病原菌种类,于2021年7月在甘肃省景泰县条山农场玉米种植区采集病样,经稀释分离法进行病原菌分离纯化,并通过致病性测定、形态学观察、生理生化特征观察及16S rDNA和gyrB序列分析相结合的方法对病原菌进行鉴定。结果表明,选取的代表性菌株B1-0和B2-1均能使玉米叶片发病,为革兰氏阳性致病菌,产芽胞;该病原菌需氧性、运动性、明胶液化、接触酶试验、柠檬酸盐利用、马铃薯腐烂试验均为阳性;甲基红试验阴性;能利用D-甘露醇、麦芽糖和葡萄糖,不能利用甘油和肌醇,不能水解淀粉,在4℃、40℃和5%NaCl条件下均能生长。构建基于16S rDNA和gyrB的系统发育树,B1-0和B2-1与短小芽胞杆菌Bacillus pumilus(ATCC7061、BKS1-108、AUEC29、BP-hd-1、NMTD17和17)亲缘关系最近,聚在一个分支。因此,将该病原菌鉴定为短小芽胞杆菌B.pumilus。研究结果将为玉米细菌性叶部病害的研究和综合防治提供基础数据。In order to identify the pathogen that caused maize leaf decay,disease samples were collected in July 2021 in the maize planting region of Tiaoshan Farm,Jingtai county,Gansu province.The pathogen was isolated from diseased tissue by method of dilution separation,single colony was purified,and pathogenicity was tested through spray inoculation indoors.The pathogen was identified by morphology observation,biochemical and physiological characteristics analyses,and phylogenetic relationship analysis of 16S rDNA and gyrB.The results showed that the two strains(B1-0 and B2-1)reproduced the original symptoms,therefore they were the causative agent of the observed maize leaf rot disease.The two strains were Gram-positive pathogenic bacterium,and produced endospore.These indexes were positive,including aerobism,motility,gelatine liquefaction,catalase test,citrate utilization and potato rot test,while methylene red test was negative.They could utilize D-mannitol,maltose and glucose,grow in 5%sodium chloride solution,at 4℃and 40℃,but couldn’t utilize glycerol and inositol and hydrolyze starch.In addition,construction of the phylogenetic tree of strains B1-0 and B2-1 based on 16S rDNA and gyrB indicated that they had the closest phylogenetic relationship with Bacillus pumilus strains(ATCC7061,BKS1-108,AUEC29,BP-hd-1,NMTD17 and 17)due to their cluster in one branch.Thus,the pathogen causing maize leaf rot was identified as B.pumilus.The above results will provide basic data for the study and comprehensive control of maize bacterial leaf diseases.

关 键 词：玉米 细菌性病害 短小芽胞杆菌 分离鉴定 16S rDNA GYRB 

分 类 号：S435.131[农业科学—农业昆虫与害虫防治]