ABSTRACT
Viruses are considered as one of the most potential groups of pathogenic microorganisms under consideration for control of biological insect pest. Approximately, more than 1200 virus–host associations have been discussed and majority of them are found in order Lepidoptera (83%), Hymenoptera (10%), Diptera (4%), and few examples from Coleoptera, Neuroptera, Orthoptera, etc. Biopesticides are gaining escalating significance as they are alternatives to chemical pesticides and are central component of many pest management programs including bacteria, fungi, entomopathogenic viruses, nematodes, and plant secondary metabolites. The virulence potential of several biopesticides (nuclear polyhedrosis virus (NPV), bacteria, and plant product) was successfully examined under laboratory conditions and the selected ones were also evaluated under field situation with huge promises. In recent years, there has been a large number of agreements between pesticide companies and bioproduct companies that advocate the 72commercial importance of viral-biopesticides. In comparison to chemical pesticides, viral-biopesticides are more effective, environment friendly and economical, because they have no detrimental residues detected, biodegradable and can be cheaper when locally produced. Three major classes of biopesticides are available such as microbial pesticides consisting of entomopathogenic bacteria (e.g., Bacillus thuringiensis), fungi (e.g., Trichoderma spp.), or viruses (e.g., Baculovirus) including their metabolites in some cases, entomopathogenic nematodes and protozoa also used. Biopesticides can be applied through various ways such as, augmentative releases, or through conserving existing field populations of natural pest control agents. The main aim of this chapter is to review the important and basic functions of major viral-biopesticides in the past and also discuss the future prospects for the development of new biopesticides.
