Coffee Thrips, Diarthrothrips Coffeae Williams (Thysanoptera: Thripidae) a Threatening Pest to Coffee ( Coffeaarabica L.) Production in Southern Ethiopia

Ethiopia is the origin of coffee (Coffeaarabica L.) and coffee is one of the most valuable crop in the country. However, its production is constrained by various factors both biotic and abiotic such as insect pests, diseases, weeds, poor management practices, soil infertility and poor pricing. Among insect pests, coffee thrips (Diarthrothripscoffeae) is becoming potentially important insect pest of coffee production in Southern Ethiopia. The aim of this study was to assess the occurrence, incidence and distribution of coffee thrips in the major coffee growing of southern Ethiopia. Following the outbreak of a coffee thrips infestation on coffee trials at Awada Agricultural Research Sub-center in March 2017, field surveys were conducted at different coffee testing site and farmers’ fields. During surveys, coffee plants were examined visually as well as aided with magnifying glasses at different growth stages of the crop. The infestation of the coffee thrips was carefully examined by randomly taking ten to fifty plants from each field using a 10x hand lens for the presence or absence of coffee thrips. Result indicated that the pest was heavily infested and widely distributed in survey areas of coffee plantation field. High infestation level and damage level occur at Awada Agricultural Research Sub-center station and followed by Amarokelle sub-station site, Dale Woreda (farmers’ fields) and Lekutesting site. Low infestation and damage level occour at Wonago sub-station site, Kumatotesting site, Dillatesting site, Shakiso Woreda (farmers’ fields) and Adola Woreda (farmers’ fields). A large mass of coffee thrips were visible on upper and lower leaves coffee and observed at surveys areas regardless age and varieties coffee plants. Coffee thrips was found to feed on upper and lower leaves of coffee and green shoots makes irregular grey or silvery patches covered by numerous tiny black spots as a result of the sucking of the plant fluids and removal of the chlorophyll and other plant pigments. Attacked of the plant by the pest gradually drying of the leaves and ultimately leading to the death of the whole plant. Highest infestation and damage level were occurred in March and become lower and lower in April and May and disappear in June of 2017.This may due to high drought and high temperatures occur in the March. This study important for farmers, researchers, agricultural extension experts and development agentsto aware the problem coffee thrips need to be alerted, trained on the identify and damage symptoms so that they can detect the infestation by the coffee thrips as early as possible.