Population dynamics of insect pests and their natural enemies on okra, Hibiscus esculentus L. (Malvales: Malvaceae), in Peshawar, Pakistan

Abstract

Okra is attacked by many insect pests in Peshawar, Pakistan. For efficient control of insect pests of okra, population dynamics of insect pests and its associated natural enemies is utmost important. The present research project was carried out at the New Developmental Farm (NDF) of the University of Agriculture, Peshawar (UAP) during 2009. Whitefly Bemisia tabaci (Gennadius), aphids Aphis gossypii (Glover), leafhopper Amrasca biguttula biguttula (Ishida), leaf beetle Cerotoma trifurcate (Forster), red cotton bug Dysdercus koenigii (Fabricius) were the major insect pests while Ladybird beetle Coccinella septempunctata (Linnaeus), spider Dictyna sp. (Linnaeus) and ant Solenopsis invicta (Buren) were the natural enemies recorded on okra. Densities of insect pests as well as their natural enemies peaked in June-July. Highest density of the pests recorded were 0.81 B. tabaci per leaf on 30th June, 3.56 A. gossypii per leaf on 23 rd June, 47.03 A. biguttula biguttula per leaf on 7 th July, 0.14 C. trifurcate per leaf on 14 th July and 1.03 D. koenigii per leaf on 21 st July. Highest density of 0.58 C. septempunctata per leaf was on 21 st July, 0.36 Dictyna sp. per leaf on 21 st July and 2.25 S. invicta per leaf on 16 th June. The present work might help in devising IPM against insect pests of okra especially using its natural enemies in Peshawar.