Abstract

Exploring of endophytic Bacillus subtilis as an agent of biocontrol for walnut canker

Author(s): ZhongdongYu, JiaoliWang, Guanghui Tang, Meizhi Zhai

One endophytic bacteria was found with strong inhibition to walnut canker pathogen, Botryosphaeriadothidea, on medium PDA during dual culture. Field investigation within 2 years after scaled inoculation verified this bacteria can be explored as potential function agents of biocontrol for walnut canker disease, with 84.1% cured rate and 9.6% new occurred rateat 3 months later at Sept., and 3.2% new occurred rate at next Sept, compared with 60.5% cured rate and 24.5 % new occurred rate of fungicide tebuconazole at current year, while 25.6% of new occurred rate in next Sept. Sequences of 16S ribosome DNA showed this bacteria is identical with Bacillussubtilis. Functional gene of TasA detection revealed it secret antimicrobe piptidase, which can inhibit pathogen sporulation and can be used in field for walnut canker suppression.