Infestation of pulse seeds by bruchids commences in the field before the seeds are harvested.

There are many constraints hindering productivity of pulses including the heavy losses during storage which forces us to import pulses from other countries to meet the growing needs of the burgeoning population.

Damage starts right from the field and hence the pest is referred to as carry-over pest. Though the field infestation ranges from 7-10 per cent it reaches 100 per cent during storage.

During storage, the females of Callosobruchus lay single eggs on legume seeds. The hatching larva chews and bores into the seed beneath the oviposition site and feeds on the tissues.

The life cycle from egg to adult is completed in 25-30 days. However, the lifecycle varies with the type of pulse and season.

— The seeds should be sun-dried adequately to reduce the moisture content.

— The seeds meant for consumption can be stored as split dal to avoid bruchid infestation. Gunny or cloth bags can be used for short term storage while poly-lined gunny bags would be helpful for medium term storage.

— Soaking the gunny bags with malathion at 3 ml/lit prior to storage checks the infestation effectively. Spraying of the cloth/gunny bags and walls of the storage godown with malathion at 2 ml/lit or dichlorvos 2 ml/lit may also be followed.

— The seeds can be mixed with malathion 5 per cent D (1 kg) or neem oil (1 lit) or pungam oil (1 lit) or monocrotophos 36 SL (400 ml) per 100 kg of seeds meant for sowing.

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