Differential effects of plant growth promoting rhizobacteria on chilli (Capsicum annuum L.) seedling under cadmium and lead stress

Rapidly increasing worldwide industrialization has led to many environmental problems by the liberation of pollutants such as heavy metals. Day by day increasing metal contamination in soil and water can be best coped by the interaction of potential plant growth promoting rhizobacteria for plant growth. The effect of plant growth promoting rhizobacteria (PGPR) treatment on growth of chilli plant subjected to heavy metal stress was evaluated. Growth of chilli plant was examined with inoculation of two isolated PGPR (Lysinibacillus varians and Pseudomonas putida) under cadmium (30 ppm), lead (150 ppm) and the combination of heavy metal (Cd+Pb) stress condition. Among these two bacteria L. varians produced slightly better plant growth enhancement. Different growth parameters of chilli plants were reduced under heavy metal stress. Whereas, Cd and Pb tolerant PGPR inoculation, in root associated soil, enhanced plant growth development under test heavy metal contaminated soil. So, these PGPRs may easily be used as bio-fertilizers which will nullify the adverse effect of heavy metal on plant growth.