番茄疫霉根腐病生防菌的分离鉴定及其防治效果

 利用平板对峙法从山东寿光采集的土样中筛选出1株对番茄疫霉根腐病菌Phytophthora capsici Leonian具有较好拮抗作用的生防菌株ZF50,抑菌率为76.26%。经形态学、生理生化特性以及系统发育树分析,确定菌株ZF50为贝莱斯芽胞杆菌Bacillus velezensis。该菌株具有较广谱的抑菌能力,且在活体盆栽和田间小区条件下,将浓度为1×10⁸ cfu·mL^-1 ZF50菌悬液10 mL灌根后,对番茄疫霉根腐病的防治效果最好,盆栽防效为55.55%,田间小区防效为43.52%;且该菌株还具有明显的促生效果和产吲哚乙酸的能力。

Identification and control effect of a biocontrol bacterium against Phytophthora root rot of tomato

A biocontrol strain ZF50 with good inhibitory effect on the growth of Phytophthora capsici Leonian, the causal agent of tomato phytophthora root rot, was isolated in the soil sample from Shouguang, Shandong Province using dual culture method. Based on morphological, physiological and biochemical characteristics, as well as phylogenetic analysis, the strain ZF50 was identified as Bacillus velezensis. This strain has a broad antibiosis spectrum. In both pot and field trials, root drenching with 10 mL culture suspension of ZF50 (1×10⁸ cfu·mL^-1) showed the best protection of tomato against Phytophthora root rot, with the efficiencies of 55.55% and 43.52% in the pot and field trails, respectively. Moreover, the strain ZF50 is able to produce indoleacetic acid and promote plant growth.