Cotton Bollworm Helicoverpa Armigera (Hubner, 1809) (Lepidoptera: Noctuidae) and Development of Integrated Pest Management Platform

Abstract

The cotton bollworm Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae),is a polyphagous and adaptive pest that currently attacks several crops including cotton.The present article undertakes the assessment of feeding preference and damage potential of this pest as well as better control options are made. In cotton, all stages of plant growth may be attacked, but reproductive tissue is preferred. Seedlings can be tipped out when terminal buds are eaten, chewing damage to squares and small bolls may cause them to shed, and injury to maturing bolls can prevent normal development and can lead to secondary fungal infections such as boll rot. Consequently, cotton bollworm larvae damage to squares, flowers, green bolls and tender shoots results in significant reduction both in yield and quality of cotton. Third instar larvae prefer to feed more on flowerswhile fifth instars on bolls. In case of H. armigera pest control, the most appropriate alternative to insecticidesis to adopt a system to monitor the pestilence and the level of pesticide control in order to make a proper decision. A direct egg and first instar caterpillar count is recommended for cotton crop for two times per week at the beginning of the plant’s germination and until 30 or 40% of the plants show open buds. The light traps and pheromone traps are sensitive for the detection of initial populations, they are more specific and make counting easier and quicker.Destroy left over material from crop and use resistant materials like genetically modified plants, which expel Bacillus thuringiensis (Bt) toxins.Biological control is mentioned as a supporter in the management of H. armigera, wherein more than 15 species of the parasitic Trichogramma, attack to the eggs.Management of beneficial parasites or insects and the use of microbial agents like baculovirus can be encouraged.Chemical pesticides should be used at pest’s levels of action and use selective pesticides, with rotation of the mechanism of action of the products, in order to alleviate the pressure from the selection of active ingredients. The strategy to prevent insecticide resistance includes rotation between chemical groups with different modes of action, limiting the time period during which an insecticide can be used and limiting the number of applications of one particular insecticide. A regional approach is suggested for the management of H. armigera, by taking into consideration the number of generations, migration capacity and its highly polyphagous quality.