ISOLATION OF INSECTICIDAL MOLECULES FROM CASSAVA AND FORMULATION OF BIO-PESTICIDES AGAINST SOME IMPORTANT PESTS OF HORTICULTURAL CROPS

Injudicious use of chemical inputs in agriculture poses challenge to sustainable agriculture. Cassava (Manihot esculenta Crantz) is a climate resilient crop cultivated in tropical and subtropical countries for its tuber as food, feed, and industrial products. Nevertheless, owing to the presence of Cyano-glucosides, leaves and tuber rinds are often thrown as waste or rather underutilized. The insecticidal principles from such bio-waste have been isolated and made formulations to manage certain important pests of horticultural crops. Current management strategy relies upon application of very toxic synthetic insecticides, although complete control of the pests could not be achieved. An extensive laboratory and field study was conducted on insects of contact applications were possible. Excellent package of control was developed both by prophylactic and curative means against the banana weevil (Odoiporous longicollis Oliver and Cosmopolitus sordidus Germer) management and over many of the noxious pests of vegetable and fruit crops. Lethality studies suggest the scope of cassava bio-pesticides as an alternative over synthetic pesticides specifically to the borer and sucking pests. The thick waxy coating of mealy bug and white fly were a major hurdle to the synthetics to act while cassava bio-pesticide formulation removes it by a spray to expose it and kill. Dose, concentration and application strategies of the bio-formulation have been standardised individually for some of the major pests, and large scale validation was done at the farmers’ fields in three geographically and agro-climatically distinct zones of Kerala state, India and established its potency to manage the dreaded pests.