Gram Pod Borer
· Gram · Pigeonpea · Chickpea
The larvae feed on all parts of the plant, but they prefer flowers and pods. Black holes are visible on the pods. Sometimes larvae can be observed hanging out of the pods while feeding. If no flowers or pods are available - larvae may also feed on leaves and shoots. Severe infestations cause defoliation
Adults are about 1.5 cm long and have a wingspan of nearly 4.0 cm. Their grey, brownish body has a hairy thorax and light-brown forewings with a dark brown band lined with blackish spots on the margins. The hindwings are white with a yellowish outline and a broad black band with a paler patch along the margin. Females lay yellowish white eggs on flowering plants or plants that are about to flower. The larvae's aspects vary depending on their development stages, but they all have a uniformly pale belly. As they mature, they develop little black spots and two bright white or yellow stripes along their flanks. The duration of the different life stages is tightly linked to environmental conditions, mostly temperature and the availability of food.
This approach is highly dependent on the type of crop. Try to keep up a population of beneficials insects parasitizing or attacking Helicoverpa in and around your field. Trichogramma wasps, Microplitis, Heteropelma, Netelia sp., predatory bugs like the big-eyed bug, glossy shield bug and spined predatory shield bug limit its development. Ants and spiders attack the larvae. Bio-insecticides based on NPV (Nucleopolyhedrovirus), Metarhizium anisopliae, Beauveria bassiana and Bacillus Thuringiensis can also be used. Botanical products, such as neem extract and chili or garlic extract can be sprayed on the foliage to control the pest.
Consider an integrated approach with preventive measures together with biological treatments. Monitor population levels to ascertain the necessity of a chemical approach. The insect has developed a certain degree of resistance to insecticides based on pyrethroid.