Paenibacillus lentimorbus induces autophagy for protecting tomato from Sclerotium rolfsii infection

Publication date: Available online 19 July 2018Source: Microbiological ResearchAuthor(s): Ritu Dixit, Lalit Agrawal, Surendra Pratap Singh, Prateeksha, Poonam C. Singh, Vivek Prasad, Puneet Singh ChauhanAbstractDuring biotic stress, plants use several mechanisms to protect themselves that include the production of reactive oxygen species (ROS), induction of pathogenesis-related proteins and cell death. Some plant growth promoting rhizobacteria (PGPR) are known to act as bio-control agents that protect crops against pathogens. The biocontrol activity of PGPR Paenibacillus lentimorbus (B-30488) against Sclerotium rolfsii showed previously where several defense-related genes were upregulated with ROS induction in tomato. We further evaluate the other possibility, i.e. role of autophagy in enhancing defense in tomato using PGPR. Confocal microscopy revealed the presence of an acidotropic dye Mono Dansyl Cadaverine (MDC) stained autophagosomes in B-30488 treated healthy and infected plants. These autophagosomes almost disappeared in plants treated with an autophagy inhibitor chloroquine. The results were also confirmed by ultrastructural analysis of leaf tissues using transmission electron microscopy. Enhanced expression of autophagy-related genes was also monitored in B-30488 primed fungal infected tissues as compared to control by qRT-PCR. Results of ROS accumulation, fluorescence, confocal and transmission electron microscopy and gene expression analysis revealed induction of a...
Source: Microbiological Research - Category: Infectious Diseases Source Type: research