Disease Symptom and Effect of Water Potential on Mycelial Growth of Botryosphaeria dothidea Associated with Chestnut Tree

Botryosphaeria dothidea에 의한 밤나무의 병징과 병원균의 균사생장에 미치는 Water Potential의 효과

Infection rate of chestnut tree by Botryosphaeria(Dothiorella) dathidea was about $10\%$ at Gapyung area. disease symptom of chestnut did not appear in October but appeared in November, showing $50\%$ in May in ext year. B. dothidea was more pathogenic to chestnut than did Catinula sp. and Fusicoccum sp. B. dothidea uses soft rot, but Catinula sp. and Fusicoccum sp. causes dry rot. Mycelial growth of B. dothidea was optimal at $28^{\circ}C$. Mycelial growth was stimulated when water potential decreased from -2 bars to -12 bars and declined from -12 bars to -60 bars.