水稻纹枯病菌拮抗细菌的筛选及鉴定  

Screening and evaluation of antagonistic bacteria against Rhizoctonia solani

作　　者：陈思宇[1] 陈志谊[1,2] 张荣胜[2] 

机构地区：[1]南京农业大学植物保护学院,南京210095 [2]江苏省农业科学院植物保护研究所,南京210014

出　　处：《植物保护学报》2013年第3期211-218,共8页Journal of Plant Protection

基　　金：公益性行业(农业)科研专项(201103002-3);江苏省自主创新资金项目(CX(11)2045)

摘　　要：为获得对水稻纹枯病有生防效果的拮抗细菌,从江苏南京、徐州和常州等地采集的土样中分离细菌分离物1914株,采用平板对峙法筛选获得70株对水稻纹枯病菌有较强抑菌活性的分离物,其中11株对5种水稻病害病原菌均有抑制作用;对11株拮抗菌进行田间防效和室内促生试验,测定菌株分泌的抑菌物质和促生物质,并进行种属鉴定。结果表明,拮抗菌对水稻纹枯病的盆栽和田间小区防效在48.41%和43.03%以上;均可产生蛋白酶与嗜铁素,而不产生几丁质酶,除XF-174外其余10个菌株均可产生纤维素酶;对水稻苗株高和鲜重具有促生作用,并均可产生赤霉素(GA3);除ZF-273和XF-174外的9个菌株可产生吲哚乙酸(IAA),且细菌发酵液中IAA和GA3含量与水稻株高和鲜重的增长率呈正相关。结合各菌株形态特征、生理生化特性和16S rDNA与gyr-B序列分析结果,鉴定SF-181为枯草芽胞杆菌Bacillus subtilis,XF-174为荧光假单胞菌Pseudo-monas fluorescens,其余9个菌株为解淀粉芽胞杆菌B.amyloliquefaciens。To obtain antagonistic bacteria for biocontrol on rice sheath blight, 1 914 bacterial strains were isolated from the rice soil, vegetable soil and other wild soil covered by plants in Nanjing, Xuzhou, and Changzhou in Jiangsu Province. Seventy strains which had strong inhibitory activities against Rhizoctonia solani were screened using plate confrontation method. Eleven strains could inhibite 5 kinds of rice pathogens had broad-spectrum antimicrobial effects. The field efficacy and indoor growth-promoting test of the 11 strains were carried out, bacteriostatic substances and growth-promoting productions were determined, and 11 strains were taxonomically identified. The results showed that the 11 strains antagonistic bacteria had great effects on control of rice sheath blight, with the efficacy more than 48.41% and 43.03% in pot and field trials, respectively. All of 11 strains antagonistic bacteria could produce protease and siderophore, but not produce chitinase, and 10 strains could produce cellulose except XF-174. The 11 strains antagonistic bacteria had promoting effects on rice stem length and fresh weight. All of them could produce GA3, 9 strains could produce IAA except ZF-273 and XF-174, meanwhile IAA and GA3 contents in the fermentation broth were positively correlated with the growth rate of stem length and fresh weight. Base on morphological characteristics, physicochemical properties, 16S rDNA and gyr-B sequence analysis appraisal, SF-181 was identified as Bacillus subtilis, XF-174 was identified as Pseudomonas fluorescens, other 9 strains were identified as B.amyloliquefaciens. These bacterial biocontrol agents could be recognized as resources for well biologically controlling the rice diseases.

关 键 词：水稻纹枯病菌 拮抗细菌 筛选 防治效果 促生作用 

分 类 号：S435.111.42[农业科学—农业昆虫与害虫防治] S476[农业科学—植物保护]