Biological Control of the Cassava Hornworm Erinnyis ello (Lepidoptera: Sphingidae)

Several Lepidoptera attack cassava; of these the cassava hornworm, Erinnyis ello (L) (Sphingidae), is the only serious lepidopteran pest throughout the cassava-growing regions of the Neotropics. Severe attacks cause complete plant defoliation, losses in bulk root production, and lower root quality. Hornworm attacks may be sporadic, are often cyclic and usually unpredictable. Farmers often react to severe attacks by excessive, ill-timed applications of pesticides that may result in resurgence of this pest. Biological control offers an economically feasible and environmentally sound alternative. Approximately 40 natural enemies have been identified including egg and larval parasites, egg, larval, and pupal predators, fungi, bacteria and a virus. Because of the migratory behavior of hornworm adults, this abundance of natural enemies does not prevent periodic hornworm outbreaks. A hornworm baculovirus is highly effective in control of E. ello, and is being utilized by cassava farmers in southern Brazil.