辣椒疫霉菌拮抗细菌的筛选、鉴定及防效测定

从天津、河北、山东、山西、福建、河南及江苏等地蔬菜根际土壤中分离细菌1万余株,从中筛选出对辣椒疫霉菌Phytophthora capsici有明显拮抗作用的细菌802株,进一步用立枯丝核菌Rhizoctonia solani、番茄灰霉菌Botrytis cinerea及瓜果腐霉菌Pythium aphanidermatum为靶标筛选出对以上病原真菌有较好拮抗作用的菌株62株。对辣椒疫病防效温室盆栽实验结果表明,6个菌株防效在70%以上,其中菌株TB1340防效最高,达到82%。菌株TB1340生物学特性测定结果表明其具有较强的产生几丁质酶、纤维素酶和β-1,3-葡聚糖酶活性。经16S rRNA基因序列分子鉴定结合形态学观察,菌株TB1340被初步鉴定为芽孢杆菌Bacillus sp.。

Screening,identification and biocontrol effect determination of antagonistic bacteria against Phytophthora capsici

More than 10 000 bacterial strains were separated from rhizosphere soil of vegetables from Tianjin, Hebei, Shandong, Shanxi, Fujian, Henan and Jiangsu, from which 802 strains exhibiting obvious antagonistic effect on Phytophthora capsici were selected. We further screened 62 strains having better antagonistic effect on Rhizoctonia solani, Botrytis cinerea and Pythium aphanidermatum from these 802 strains. Greenhouse pot experiments against P. capsici show that control effects of 6 strains are higher than 70%, Control effects of strain TB1340, 82%, are highest. Determination results of its biology characteristics demonstrate that it has stronger activity producing chitinase, cellulase and β-1,3-glucanase. It is preliminarily identified as Bacillus sp. by 16S rRNA sequence analysis combined with morphology observation.