The incidence of the Southern Blight (Sclerotium rolfsii) in green beans (Phaseolus vulgaris) in Çanakkale province and the effectiveness of some fungicides against the disease

ABSTRACTSouthern blight, incited by Sclerotium rolfsii Sacc., is a destructive disease ofmany horticultural and agronomic crops in tropic and sub-tropic regions of the world.As like many soil-borne fungal pathogens, S. rolfsii is also hard to control once it isestablished in the field. The fungus threats the green-bean growing areas in Çanakkaleprovince. The aims of this research are to find out the distribution and severity ofsouthern disease in Ayvacık and Ezine, Çanakkale. Twenty five gren beans fields inAyvacık and Ezine was included in the survey. Each field was surveyed three times in aseason in a week intervals. Out of 25 fields, only 6 were found to be not infested withthe pathogen. The disease severity varied between %0 and %40 in survey areas. Inorder to evaluate the effectiveness of the fungicide, detached leaf experiment wasperformed.seven diiferent fungicides containing different active ingredients were used:captan, benomyl, azoxystrobin, diniconazole, tebuconazole, iprodion and metalaxyl. Asa result of the experiment tebuconazole, azoxystrobin and diniconazole was the mosteffective fungicides, while ipradion, captan and metalaxyl exhibited less effectiveness.Benomyl had no effect on the lesion size and mycelial growth. More resistant varietiesand suitable control measurements should be developed for the such pathogens withwide host spectrum.Key words: green beans, Sclerotium rolfsii, white mold, fungisides, plant diseaseresistanceII