Role of Plant Growth Promoting Rhizobacteria in Disease Management

The change in global climate over the past decades led to rapid increase of various new plant disease outbreaks. Utilizing synthetic chemicals for controlling diseases has always been the ultimate option for disease management. However, modernday agriculture calls for a sustainable approach towards disease management which will improve crop health as well as be environmentally sound. Plant growth-promoting rhizobacteria (PGPR) play a crucial role in this approach. They are a free-living, diverse group of beneficial microorganisms that colonizes plant roots and improve plant health by suppressing soil-borne pathogens and inducing systemic resistance. They achieve this through various mechanisms, such as, antibiotic and siderophore production, that aid in pathogen control and promoting plant health, through competition with pathogens for resources, minimizing the pathogen population and also modulating plant defense responses through induce resistance via jasmonic acid and ethylene dependent pathways. Unlike synthetic chemicals, which have a negative impact on human health and the environment, PGPRs are natural and non-toxic. They can be used as an alternative to traditional synthetic agro-chemicals. They are effective in controlling soil-borne diseases and also act as bio-inoculants or biofertilizers to enhance crop yield. Bacterial strains like Bacillus, Pseudomonas and Streptomyces are known to exhibit effective control for soil-borne diseases in crops like rice, wheat and maize. Integrating PGPR into agricultural practices not only reduces the heavy reliance on synthetic chemicals but also, directly and indirectly, enhances the soil health and promotes environment-sound agriculture. This chapter explores the potential of PGPR as a key player in innovative and eco-conscious plant disease management strategies.