Fusarium Wilt of Winter Daphne (Daphne odora Thunb.) Caused by Fusarium oxysporum

Severe wilt disease epidemic was found on winter daphnes (Daphne odora Thunb.) cultivated in farmers, nurseries in Suncheon, Jeonnam in 2003. Typical symptoms appeared on the leaves of winter daphne as yellowish wilts and turned brown from the lower leaves on the same plant. Severely infected leaves were defoliated, resulting in blight of stems and eventual death of the entire plant. Black decayed vascular tissues were distinctly observed in a wilted plant. Fusarium sp. was isolated from the diseased plants repeatedly and its pathogenicity was confirmed by artificial inoculation on healthy plants. The fungus was identified as Fusarium oxysporum on the basis of the morphological and cultural characteristics on potato dextrose agar and carnation leaf agar. The optimum temperature for fungal growth was around $25{\circ}C$ and the fungal growth was inhibited by metconazole, triflumizole and trifloxystrobin on potato dextrose agar. This is the first report on the wilt disease of winter daphnes caused by F.oxysporum in Korea.