Distribution of Coffee Berry Disease (Colletotrichum kahawae) in Seyo Nole District, Oromia Region of Ethiopia, and In-vitro evaluation of plant extracts and Fungicides against the pathogen
Fikadu Dingeta1, Ararsa Leta2, Amsalu Abera3, B. Chandra Sekhar Singh4*
1,2,3,4Department of Plant Sciences, School of Agriculture, College of Agriculture and Veterinary Sciences, Gudar Mamo Mezemir Campus, Ambo University, P. O. Box: 19, Ambo, Ethiopia East Africa 4*Corresponding author - Email: singhsekhar960@gmail.com
ABSTRACT
Coffee Berry Disease (CBD), caused by Colletotrichum kahawae is a significant challenge to Arabica coffee cultivation in Ethiopia. This study aimed to assess the current status of CBD in the Seyo-Nole district of the West Wellega Zone and evaluate the effectiveness of various plant extracts and fungicides against the pathogen. Ninety coffee farms were surveyed to determine the disease’s prevalence and severity. Diseased berries were collected from each farm for pathogen isolation, characterization, and in-vitro antifungal management evaluation. The evaluation of botanicals and fungicides was conducted using food poison techniques, measuring the radial growth of the fungus to determine antifungal activity. Seven aqueous and five ethanol extracts of medicinal plants were tested at 25% (w/v) concentration, along with two fungicides at 2000 ppm. The survey results showed significant variation in CBD distribution and status among and within Peasant Associations, with disease incidence ranging from 25% to 45.3% and disease severity from 23.5% to 45.23%. The in-vitro antifungal assay results indicated that both fungicides and medicinal plant extracts significantly inhibited (p<0.01) the pathogen. Propiconazole and Difenoconazole achieved the highest inhibition (100%).Among the aqueous plant extracts, Papaya Leaf Extract showed the highest inhibition (97.71%), followed by Eucalyptus Leaf Extract (96.50%), with the lowest inhibition recorded for Orange Leaf Extract (77.10%). The ethanol extracts exhibited superior results, with Papaya Leaf Ethanol Extract achieving 99.28% inhibition, followed by Eucalyptus Leaf Ethanol Extract (98.34%), and the lowest inhibition by Acacia Leaf Ethanol Extract (87.29%). The use of Propiconazole, Difenoconazole, and plant extracts from Carica papaya, Eucalyptus saligna, and Datura stramonium for the management of Coffee Berry Disease. The plant extracts exhibiting significant inhibition should undergo further testing and formulation.