Biological control of chickpea pod borer, Helicoverpa armigera Hubner (Lepidoptera: Noctuidae): A global concern

Chickpea (Cicer arietinum L.) is grown widely in the world because the seeds are rich source of protein for the rapidly increasing population. However, the production and productivity of chickpea have been experienced drastically because of biotic and abiotic stresses. It is vulnerable to a broad range of pathogens and the mainly severe pest being gram pod borer, Helicoverpa armigera. For the management of this serious pest, application of insecticides has several adverse effects on living organisms and the environment as a whole, the use of biological agents for chickpea improvement appears to be appropriate approach. Various studies by different scholars on the effect of different bio-agents against H. armigera have been carried out and found to confer resistance to pod borer. The use of Bacillus thuringiensis (Bt) based microbial insecticides have become an integral part of IPM approaches, particularly because these preparations provide an environmentally suitable alternative to the generally hazardeous broad-spectrum chemical insecticides. These bacterial insecticides like Nuclear Polyhedrosis Virus (NPV), which is target specific and exert no effect on beneficial organisms (e.g. parasitoids and predators). Most natural populations of H. armigera have at least some degree of infection by species-specific NPVs. When the degree of NPV infection can be enhanced, H. armigera larval population can be decimated, without deleterious effects on any other organisms. Various potentially effective parasitoids, like ichneumonid, Campoletis chloridae and Trichogramma spp., are found parasitizing eggs and larvae of H. armigera infesting chickpea. Various insectivorous birds and use of bird perches have long been observed to be effective predators of H. armigera larvae. Similarly various plant extracts have shown insecticidal properties and can be used effectively on field crops. Use of different bio-agents and botanicals having easy ways of formulation, cost effective, environmentally suitable and no or