Reaction of Gidami Coffee Collections against the Major Diseases

Ethiopia's largest export commodity is coffee arabica, one of the most significant goods that significantly contribute to the national economy. However, diseases including coffee berry, coffee leaf rust, and coffee wilt have been significantly reducing its yield. In order to assess Gidami coffee arabica accessions’ reaction to serious fungal infections, this study was started. The total of 100 genotypes was evaluated under Gera and Haru field situations for these major diseases. Whereas, 92 accessions with two checks were tested under greenhouse condition for coffee wilt. The results showed a highly significant variation (p<0.001) among genotypes in both conditions with 0–51%, 4–36%, and 0–100% disease severity ranges respectively. Except the four accessions namely G67/13, G71/13, G54/13, and G66/13, most of them showed susceptible reactions to CBD under Gera conditions. As well, 36 and 12 coffee accessions revealed <10% CLR reactivity at Haru and Gera conditions respectively. But none of the accessions had resistance levels higher than the two checks (Challa and 8136) at either of the locations. In other word, Gera had much greater levels of CBD and CLR pressure than Haru. On the other hand, only two accessions, G57 and G20, showed 100% CWD survival rate in greenhouse environments. This study showed how plant genetics and environmental variables affect diseases development and demonstrated that the response of Gidami coffee accessions to the major coffee diseases highly influenced by geographical and genetic variables. Therefore, continual and massive genotype screening across the locations must be taken into account in order to get resistance genotypes as the best disease mitigation to overcome the coffee diseases problem.