Biocontrol Potential of Fluorescent Pseudomonas Spp. In Controlling Rhizoctonia Basal Stem Rot Disease Caused By Rhizoctonia Solani and Promoting Plant Growth On Chilli

Abstract

The biocontrol potential of fluorescent Pseudomonas spp. isolated from rhizosphere soil of healthy chilli was evaluated against Rhizoctonia solani in causing basal stem rot disease on chilli. A total of 50 isolates out of 115 potential fluorescent Pseudomonas spp. were selected based on its percentage inhibition radial growth (PIRG) for more than 65% from dual culture assay. All 50 isolates were further screened for production of volatile organic compound, hydrogen cyanide, phosphate solubilization and indole acetic acid. Thirty-tree isolates were identified as Pseudomonas spp. using 16s ribosomal RNA sequencing. A total of 13 most potential Pseudomonas spp. were further tested for seedlings vigour index. Pseudomonas putida B5C1, Pseudomonas aeruginosa B3C56 and Pseudomonas putida B5C7 were selected with the most prominent in promoting plumule and radicle growth and significantly (P ≤ 0.05) higher than the control. The bio-efficacy of these fluorescent Pseudomonas spp. was evaluated in glasshouse for the suppression of R. solani and enhancing plant growth of chilli seedlings.