Parasitism Rates of Psyllaephagus bliteus in Eastern and Western Kenya for Biocontrol of Glycaspis brimblecombei

Abstract

The principal natural enemy of Glycaspis brimblecombei is a parasitoid Psyllaephagus bliteus Reik which has been studied to control its host. The foremost objective of this work entails studying the parasitism rates of P. bliteus in Western and Eastern Kenya after the National Forestry Resources Research Institute (NaFORRI) released P. bliteus in their Eucalyptus camaldulensis plantations bordering Western Kenya. Plantations in Busia, Bungoma and Siaya counties in Western Kenya and; Ndufa and Kiamuringa Kenya Tea Development factory in Embu County were assessed. Ten (10) E. camaldulensis trees were randomly selected from each plantation. Adult P. bliteus population was sampled by placing two yellow sticky traps on each sample tree while immature stages were assessed by opening mature lerps and observing for the presence of developing parasitoid forms, mummified nymphs or exit holes. Three assessments were carried out in three different months and generated data analyses were performed using R statistical software. Distribution maps were drawn using ArcGis. The number of exit holes differed significantly among the counties and months of assessment. The number of lerps with exit holes was highest in both December (1.81±0.21) and June (1.59±0.34) in Bungoma County. Bungoma recorded the highest parasitism rate of P. bliteus (11.61%), followed by Siaya (7.92%), Embu (5.08%) and Busia (3.54%), indicating that P. bliteus found its way into Kenya. This study provides important information on the parasitism rates of P. bliteus in Kenya, and this would guide the implementation of biocontrol program for sustainable management of G. brimblecombei in Kenya.

Keywords: Classical biocontrol, Eucalypts, integrated pest management, red gum lerp psyllid

DOI: 10.7176/JNSR/15-3-04

Publication date: September 30^th 2024