Abstract

Resistance-related enzymatic activities due to selected strains of Pseudomonas fluorescens were assayed by split root bioassay in tomato under glass house conditions. Application of P. fluorescens as seedling root dip increased the level of peroxidase (PO), polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) in tomato roots indicated the systemic resistance induced by the bacterial formulations against root knot nematode, Meloidogyne incognita. Among the four P.fluorescens isolates tested alone and in consortium with Bacillus subtilis, Bbv 57, consortial application of P. fluorescens, Pf 128 with B. subtilis, Bbv 57 recorded the highest enzymatic activity in tomato roots compared to other strains either alone or in consortium. Results indicated that P. fluorescens was capable of inducing systemic resistance against M. incognita in tomato by the accumulation of the defense enzymes like PO, PPO and PAL.

Keywords: Tomato, Plant Growth Promoting Rhizobacterium, Meloidogyne incognita, systemic resistance