First Report of Anthracnose Caused by Colletotrichum acutatum on Begonia(Begonia semperflorens Link.) Nurseries

Park, Jong Kyu; Kim, Gyoung Hee; Min, Gyung Mi; Park, Hee Jin; Hur, Jae Seoun; Kang, Beum Kwan; Kim, Heung Tae; Choi, Woo Bong; Koh, Young Jin

The Plant Pathology Journal 2006;22(1):7-10.
Published online March 31, 2006.

First Report of Anthracnose Caused by Colletotrichum acutatum on Begonia(Begonia semperflorens Link.) Nurseries

Jong Kyu Park, Gyoung Hee Kim, Gyung Mi Min, Hee Jin Park, Jae Seoun Hur, Beum Kwan Kang, Heung Tae Kim, Woo Bong Choi, Young Jin Koh

Abstract

Anthracnose severely occurred on begonia (Begonia semperflorens Link.) nurseries in Gyeongju, Gyeongbuk in July, 2004. More than 80% of begonia seedlings were diseased in the greenhouse surveyed and diseased leaves per plant were 12.1% in average. Yellowish spots occurred on the leaves of begonia as initial symptoms, and they coalesced irregularly to form large brown pleomorphic lesions. Severely infected leaves were defoliated, resulting in abnormal growth of the entire plant. Colletotrichum sp. was repeatedly isolated from the diseased plants and was identified as Colletotrichum acutatum on the basis of the mycological characteristics on potato dextrose agar and RAPD analysis. Pathogenicity of the fungus was also confirmed by artificial inoculation on healthy plants. The optimum temperature for mycelial growth of C. acutatum was around 25oC. The fungus was sensitive to azoxystrobin, bitertanol, diethofencarb-carbendazim, difenoconazole and tebuconazole. This is the first report on the anthracnose of begonia caused by C. acutatum in Korea.

Key Words: Anthracnose, Begonia, Begonia semperflorens, Colletotrichum acutatum