Effect of fungal and bacterial bioagent application on total phenolic content in rice leaves pre-inoculated with Xanthomonas oryzae pv. oryzae (Uyeda and Ishiyama) Dowson

Abstract

Present study was carried out to observe the effect of fungal and bacterial bioagents on total phenolic content in rice leaves pre-inoculated with Xanthomonas oryzae pv. oryzae and on disease severity of bacterial leaf blight of rice. Two commercial formulations of Trichoderma harzianum (PBA-1) and Pseudomonas fluorescens (PBA-2) and four formulations of fluorescent pseudomonads and Trichoderma spp. viz, P. fluorescens (Pf 83, rice leaf isolate), fluorescent pseudomonad (FLP 88, rice leaf isolate), T. harzianum (rice leaf isolate), Trichoderma spp. (isolate 40, isolated from rice field soil) were evaluated. Significantly higher mean value of total phenolic content of rice leaves was observed with the application of bioagent formulations as compared to check (pre-inoculated with X. oryzae pv. oryzae), chemical treatment and healthy plant. Maximum mean total phenolic content (342.22 ?l/g) in rice leaves was observed with Pf 83, which was followed by PBA-2 (334.44 ?l/g) and T. harzianum (330.00 ?l/g). Decrease in disease severity of bacterial leaf blight was observed with the increase of total phenolic content in rice leaves which resulted in increased grain yield and 1000 grain weight.