Importance of spittle bugs, Locris rubens (Erichson) and Poophilus costalis (Walker) on sorghum in West and Central Africa, with emphasis on Nigeria.

摘要

Locris rubens and Poophilus costalis are endemic pests of sorghum (Sorghum bicolor) in Nigeria and some other countries in West and Central Africa. Other hosts are maize, pearl millet, rice, sugarcane, and grasses. On sorghum, L. rubens lays eggs inthe epidermis of the leaf sheath. There are five nymphal instars and development from egg to adult takes about 33 days. Both species of spittle bugs feed on all growth stages and all parts of sorghum, including the panicle. Feeding symptoms include yellow leaf blotching. Severe infestations often kill young leaves and plants. Under artificial infestation in cages, the severity of damage and associated symptoms as well as grain yield loss increased with an increase in the population density of spittle bugs. Infestation by 15 pairs of adult L. rubens over a period of 5 wk reduced grain yield by 35% in 1994. It is concluded that spittle bugs are important pests of sorghum in Nigeria.