Morphometric Characterization of the Mango Tree's Mealy Cochineal, Rastrococcus invadens, on the Mango Tree in Senegal

Fruit production in Senegal is mainly for national consumption. The major critical point of mangoes and citrus fruits production is fruit ravaging insects such as Rastrococcus invadens (Homoptera, Pseudococcidae) (Willams, 1986). Originated in Southeast Asia, this cochineal was first identified in Senegal. Since then it has spread throughout this country and particularly in Natural Casamance region and Thies region. In each region we chose two farms in two different localities. In Casamance, we chose one farm in Diatock locality and another one in the locality of Oussouye. In Thies region, we sampled in Santhie and Khay localities. In each farm, we chose the mango tree which represents the major host plant of R. invadens. From each plant we collected 10 specimens. This enabled us to get 20 specimens from Casamance and 20 other specimens from Thies. Specimens were coded with regard to both the area and the type of plant they were collected from. The present work aims to take stock of the morphological and morphometric characteristics of the pest into space and time, as well as its socio-economic consequences since it has been reported in Senegal. The results revealed morphometric groups more or less distinct especially between the Niayes zone and low Casamance.