水稻稻瘟病菌拮抗细菌的筛选与鉴定

Screening and identification of antagonistic bacteria against Pyricularia grisea

采用平板测定法和盆栽试验结合筛选对稻瘟病菌具有高效抑菌活性的拮抗细菌,结果表明:从江苏省南京市、丰县、泗阳县等地的50份稻田水稻根际土壤样品中,得到1 015个细菌分离物,共获得45株对稻瘟病菌具有高效抑菌活性的拮抗细菌,其中10株对稻瘟病菌、水稻纹枯病菌和水稻稻曲病菌、水稻细菌性条斑病菌及水稻白叶枯病菌均表现出较强的广谱抗菌活性(对5种水稻病原菌平均抑制率在45%以上)。水稻苗瘟的盆栽防治效果表明:拮抗细菌T429和T392具有较好的防治效果,分别达到69.4%和61.1%。结合理化特性和16S rDNA鉴定,T429为枯草芽孢杆菌(Bacillus subtilis),T392隶属伯克霍尔德菌属(Burkholderia)。

In order to screen antagonistic bacteria against Pyricularia grisea which causes rice blast,plate isolation and a pot experiment were conduced.The results showed that 1 015 bacterium strains were isolated from 50 samples of rice rhizosphere soils in Nanjing City,Fengxian County and Siyang County of Jiangsu Province.In these strains,there were 45 strains with high bacteriostatic activities to Pyricularia grisea,10 of the 45 strains antagonistic to Pyricularia grisea,Rhizoctonia solani,Ustilaginoidea oryzae,Xanthomonas oryzae pv.oryzicola and Xanthomonas oryzae pv.oryzae,with average inhibitory rates over 45%.A pot experiment revealed that T429 and T392 had good control efficacy on rice blast at seedling stage,the inhibitory rates being 69.4%,61.1%,respectively.Based on physical and chemical characters and 16S rDNA sequencing,it could be drawn that T429 was Bacillus subtilis and T392 was Burkholderia.