Trichomes of Cotton Leaf as an Aspect of Resistance to Sucking Insect Pests

Abstract

Field experiments were conducted to study the effect of cotton leaf phenology and morphology on incidence and population buildup of sucking insect pests of cotton. Fifteen cotton cultivars were screened for trichome density and population buildup of jassids, thrips and white fly. The effect of leaf type on incidence of sucking insect pests was also determined. The results revealed that Trichome density varied with the cotton cultivars and it decreased with the age of the leaves of respective cotton cultivars. Jassid population had negative significant correlation with Trichome density. Thrips also had negative but non-significant correlation with Trichome density. However, white fly population buildup had positive significant correlation with trichome density on cotton leaves of respective cultivars. Cotton varieties with okra leaves harboured less jassids and thrips infestation as compared with normal leaf variety. However, jassids and thrips population was significantly the least on red and super okra leaves respectively. The white fly population was also significantly the least on red leaf variety Red Russian.