Pathogenicity Test of Colletotrichum kahawae in Arsi Coffee Growing Areas, Southeastern Ethiopia

Coffee is a non-alcoholic and stimulant beverage crop and belongs to the family Rubiaceae and genus Coffea. Arabica coffee (Coffea arabica L.) has been threatened by various coffee fungal diseases. Among these coffee berry disease (CBD), coffee wilt disease (CWD) and coffee leaf rust (CLR) are the major economically important coffee fungal diseases in Ethiopia. Coffee berry disease (CBD) caused by Colletotrichum kahawae is the major coffee disease in Ethiopia. Experiments were conducted under both laboratory condition. All activities were carried out using completely randomized design (CRD) with three replications. Five representative C. kahawae isolates and one C. gloeosporioides were isolated and identified from infected green coffee berry sampled from the study areas. All isolates showed pathogenic to Arabica coffee. However, there was highly significant variation (P < 0.05) among isolates on level of aggressiveness. Isolate Go34 and ShK10 were more highly aggressive to susceptible variety of Arabica coffee ″Arusa² than the remaining. Any expert can use these virulent isolates in order to generate CBD resistant variety (ies) for the respective areas. Keywords : Coffea arabica L.,  Isolates, Colletotrichum kahawae, Pathogenicity