Fungal Pathogens Associated with Postharvest Rotting of Tomato (Lycopersicon esculentum Mill.) in Eastern Ethiopia

Tomato is a very perishable and highly susceptible to postharvest fungal diseases that cause rotting of the fruits in many parts of the world including Ethiopia. Investigations were conducted to isolate and identify fungal pathogens causing post-harvest rotting of tomato fruits. Samples were collected from stores and markets in Dire Dawa, Harar, Haramaya, and Bate towns and fungal pathogens were isolated and identified. Fourteen different fungal genera were found associated with the evaluated tomato fruits. These were Fusarium spp., Alternaria spp., Saccharomyces spp., A. niger, Geotrichum spp., Penicillium spp., Mucor spp., Phoma spp., Trichoderma spp., Cladosporium spp., Helminthosporium spp., Colletotrichum spp., Rizhoctonia spp., and Diplodia spp. Fusarium spp. had the highest (46.2%) frequency of occurrence, while Trichoderma spp. were the least (0.22%) encountered. Pathogenicity tests revealed that all of the isolated fungi except Trichoderma spp. were pathogenic. Penicillium was the most aggressive genus which produced lesion diameter of 42 mm in five days. A. niger was the least (9.5 mm) aggressive species. Fusarium was identified to species level and F. oxysporium, F. chlamydosporium, F. avenaceum, F. solani, F. acuminatum, and F. sporotrichiodes were recovered. F. oxysporium was the most frequently (54.21%) recorded one, while the lowest (0.93%) was F. acuminatum. Also the highest (28.25 mm) lesion diameter was produced by F. oxysporium, while the least (20 mm) was by F. avenaceum. In conclusion, the study revealed high occurrence and distribution of diverse fungi associated with post-harvest rotting of tomato fruits in eastern Ethiopia. However, further studies are important for identifing the isolated fungal pathogens to species level except fusarium and to develop appropriate manegement options for fruit rotting fungi.