Role of secondary metabolites of actinomycetes in crop protection

Abstract

Diseases and insect pests are the major hurdle in enhancing the production of agricultural crops. The frequent use of synthetic pesticides has led to the development of pesticide-resistant pathogens and insect pests, environmental pollution, negative effects on natural enemies, human health hazards, and pollution of underground water, thereby causing ecological imbalance. The use of bacteria having antimicrobial properties has become one of the most attractive options for enhancing the sustainability of agricultural production due to their ecofriendliness, low production cost, and reduced use of nonrenewable resources. Among them, actinomycetes are the good alternative for the management of insect pests and diseases. These are the most economically and biotechnologically valuable prokaryotes. These represent a high proportion of the soil microbial biomass and have the capacity to produce wide variety of secondary metabolites. Several strains of actinomycetes have been acknowledged as prolific producer of valuable bioactive metabolites as antibacterial, antifungal, antibiotic, antiparasitic, insecticide, and herbicide. However, only a few microbial compounds are applicable at the field level or presently commercialized. Here, the authors have provided an overview of the uses and importance of actinomycetes and their secondary metabolites with special emphasis on managing insect pests and diseases of cultivated crops.