White Mango Scale, Aulacaspis tubercularis, Distribution and Severity Status in East and West Wollega Zones, Western Ethiopia

Abstract

Mango is attacked by many insect pests which reduce the quality and productivity of the crop. Among the insect pests attacking mango plant, white mango scale is the most devastating insect pest. White mango scale, was reported since 2010 from Guto Gida district of East Wollega zone. The distribution and severity of white mango scale was studied in selected 5 districts and 10 kebeles of East and West Wollega and insect infestation and the degree of damage. Results of the survey showed that from the sampled five districts white mango scale distributed to all four districts except Mana Sibu. From the survey it was known that the maximum distance white mango scale dispersed from Loko Keble (Guto Gida district, which was assumed to be the source of original infestation) was 67 km to the West and 58 km to the East direction. Distribution and severity status comparisons between sampled districts and administrative kebele‟s for the formation of clusters of white mango scale per leave per mango showed significant difference at P=0.05 indicating different pest status in the study areas. Moreover, yield data before and after mango scale appearance showed high significant difference. From the current survey it was found that white mango scale is becoming the most important limiting factor for mango production in Western Ethiopia. The dispersal rate is alarming indicating that within a short period of time the pest can invade the whole of Western Ethiopia particularly Wollega zones. Hence, due attention should be given to this pest, so that ecologically friendly management options will be made available for the mango growers in that part of the country in particular and Ethiopia in general.

Keywords: White mango scale Cluster formation Insect pest Distribution Severity status