Title The Use of Pseudomonas fluorescens P13 to Control Sclerotinia Stem Rot (Sclerotinia sclerotiorum) of Oilseed Rape
Author Hui Li1,2, Huaibo Li1, Yan Bai1, Jing Wang1, Ming Nie2, Bo Li2, and Ming Xiao1*
Address 1College of Life and Environmental Sciences, Shanghai Normal University, Shanghai 200234, P. R. China, 2Institute of Biodiversity Science, Fudan University, Shanghai 200433, P. R. China
Bibliography Journal of Microbiology, 49(6),884-889, 2011,
DOI
Key Words Pseudomonas fluorescens, biocontrol, sclerotinia stem rot, mechanisms, growth promotion
Abstract Sclerotinia stem rot (SSR) caused by the fungus Sclerotinia sclerotiorum has been an increasing threat to oilseed rape (Brassica napus L.) cultivation. Efficient and environment‐friendly treatments are much needed. Here we focus on microbial control. The Pseudomonas fluorescens P13 that was isolated from oilseed rape cultivation soil, proved to be a useful biocontrol strain for application. Morphology, physiological and biochemical tests and 16S rDNA analysis demonstrated that it was P. fluorescens P13 and that it had a broad antagonistic spectrum, significantly lessening the mycelial growth of S. sclerotiorum by 84.4% and suppressing sclerotial formation by 95‐100%. Scanning electron microscopy studies attested that P13 deformed S. sclerotiorum mycelia when they were cultured together. P13 did not produce chitinase but did produce hydrogen cyanide (HCN) which was likely one of the antagonistic mechanisms. The density of P13 remained at a high level (≥106 CFU/ml) during 5 weeks in the rhizosphere soil and roots. P13 reduced SSR severity at least by 59% in field studies and also promoted seedling growth (p<0.05) at the seedling stage. From these data, our work provided evidence that P13 could be a good alternative biological resource for biocontrol of S. sclerotiorum.