Biology of dubas bug, Ommatissus lybicus (Homoptera: Tropiduchidae), a pest on date palm during spring and summer seasons in Panjgur, Pakistan

Abstract

Dubas bug, Ommatissus lybicus is one of the major sucking pests of date palm. Both nymphs and adults suck the sap from fronds and fruit stalks. Severe infestations cause even death of date palms. Biological parameters of the bug were studied for the four consecutive generations on Kehraba cultivar during spring and summer seasons 2009-2010. The mean fecundity and longevity of male adults of first (spring) generation were significantly lower than that of second (summer) generations 2009-2010. Mean egg laying frequency, adult longevity, incubation and post ovipositional period during 1 st and 2 nd generation were 4.90, 19.50, 147.60 and 3.60; and 5.30, 21.80, 62.70 and 4.50 days, respectively. The mean nymphal development periods were 46.9 and 49.6 days in spring and summer generations with no significant difference. On the average, females have longer life duration (27.85 days) than males (18.85 days) under the similar climatic conditions and generations. This bivoltine hibernates and aestivates in the egg stage in fronds during winter and summer and on an average completes total life cycle of 1 st and 2 nd generation in 217.25 and 136.35 days, respectively. Dubas bug passes 61.43 and 38.56 % time of life cycle in eggs stage during spring and summer generations, respectively.