Plant endophytic Pseudomonas putida BP25 induces expression of defense genes in black pepper roots: Deciphering through suppression subtractive hybridization analysis

Abstract

Black pepper associated endophytic Pseudomonas putida BP25 displayed broad spectrum antagonistic activity against a wide range of plant pathogens. The molecular responses of black pepper upon endophytic colonization by P. putida BP25 was studied using a PCR based suppression subtractive hybridization (SSH) method. The transcripts induced by endophytic P. putida BP25 in black pepper included pathogenesis related proteins such as PR-4 and PR-1; reactive oxygen species (ROS) scavenging catalase and metallothionein; stress induced glutathione S-transferase; 5-enolpyruvylshikimate-3- phosphate synthase involved in phenylpropanoid metabolism. Differential expression of transcripts was validated by quantitative real time PCR (qPCR) for selected ESTs. This information helps in understanding the ability of an endophytic strain P. putida BP25 in inducing a wide array of defence responses in black pepper roots