Chapter 7 - Molecular aspects of biocontrol species of Streptomyces in agricultural crops

Abstract

Soil microorganisms are key players in determining the plant growth and crop productivity worldwide. Among different microorganisms, members of the genus Streptomyces are one of the major microorganisms which are either responsible for plant diseases suppression and growth regulation. In some cases, they are also reported for plant diseases. The plant beneficial roles involve the production of chitinases, glucanases, peroxidases, and other enzymes which can targets the plant pathogens. Moreover, the secretion of secondary bioactive metabolites such as siderophores, antibiotics and plant growth regulators, affects the plant development and immune responses, in which ultimately can alleviates the stress responses against biotic as well abiotic conditions. Moreover, Streptomyces spp. are found to significantly enhance the intensity of mycorrhizal root colonization in agricultural crops whereas root colonization by Streptomyces in legume crops, promote root nodulation frequency. Streptomyces spp. also help in minerals acquisition by the plants through organic acid production, phosphate solubilization, iron chelation, nitrogen fixation, and the elevation of mycorrhizal association with plants. The present book chapter highlights the different aspects of Streptomyces and their role the crop productivity and protection against environmental stresses.