Induction of systemic resistance by plant growth promoting rhizobacteria in crop plants against pests and diseases

Plant growth promoting rhizobacteria (PGPR) belonging to Pseudomonas spp. a re being exploited commercially for plant protection to induce systemic res istance against various pests and diseases. Mixtures of different PGPR stra ins have resulted in increased efficacy by inducing systemic resistance aga inst several pathogens attacking the same crop. Seed-treatment with PGPR ca uses cell wall structural modifications and biochemical/physiological chang es leading to the synthesis of proteins and chemicals involved in plant def ense mechanisms. Lipopolysaccharides, siderophores and salicylic acid are t he major determinants of PGPR-mediated ISR. The performance of PGPR has bee n successful against certain pathogens, insect and nematode pests under fie ld conditions. (C) 2001 Elsevier Science Ltd. All rights reserved.