In-vitro evaluation of P. fluorescens isolates for antagonistic potential against Rhizoctonia solani and Sarocladium oryzae

Abstract

Rice (Oryza sativa L.) is second most important cereal and the staple food for more than half of the world’s population. P. fluorescens is the plant growth-promoting rhizobacteria (PGPR) are the rhizosphere bacteria that can enhance plant growth by a wide variety of mechanisms like phosphate solubilization, siderophore production, biological nitrogen fixation, production of 1-Aminocyclopropane-1- carboxylate deaminase (ACC), phytohormone production, exhibiting antifungal activity, production of volatile organic compounds (VOCs), induction of systemic resistance, promoting beneficial plant-microbe symbioses, interference with pathogen toxin production etc. In the study of Twelve different isolates of P. fluorescens were tested for their antagonistic potential against Rhizoctonia solani and Sarocladium oryzae pathogens. The results revealed that among all isolates the isolate P11exhibited in-vitro maximum antagonistic potential and significantly reduced mycelial growth (23.00 mm) and percent inhibition (74.44%) of Rhizoctonia solani. Whereas among all isolates maximum reduction in mycelial growth (12.66 mm) and percent inhibition (70.55%) was recorded with isolate P29 against Sarocladium oryzae.