Role of plant growth-promoting rhizobacteria and their formulation in biocontrol of plant diseases

Abstract

Fungal phytopathogens are a major threat to crop plants. More than 60 fungal phytopathogens are known to cause various plant diseases. These diseases lead to the loss of 30 % crop yield that accounts to about 20,000 crore rupees per year in the global market. Different methods of chemotherapy have been used to control these diseases. However, uncontrolled use of chemical fungicides has severely affected the agroecosystem, leading to the development of pesticide-resistant pests and emergence of new species of pests. Increased dependence on chemicals is inevitably associated with environmentaland health hazards. In this regard, plant growth-promoting rhizobacteria (PGPR) have been found as an effective, eco-friendly, and sustainable replacement to the chemical fungicides. The present chapter focuses on antifungal traits such as siderophores, lytic enzymes, hydrogen cyanide, and antibiotics of PGPR, development of effective formulation of PGPR for longer shelf life and competitiveness with the natural environment, obstacles in formulation development, and characteristics of bioformulation. Biotechnologicalattributes of PGPR with respect to plant growth promotion, disease resistance, and iron nutrition are also discussed.