葡萄晚腐病是由Glomerella cingulata (Ston.) Spanld et Schrenk所引起,無性世代為Colletotrichum gloeosporioids Penz,本菌可由同絲型方式產生有性世代。無性世代的變異甚大,依其落形態可分為菌絲型、胞子型和中間型。病原菌寄主範圍廣,可感染葡萄的果實,且本病原菌侵入幼果後,其菌絲能在果皮下組織蔓延,並產生胞子。病原菌的生長適溫為20~32℃,最適生長的酸鹼度為pH 3.4~5.0。病原菌可在休眠芽及枝條越冬,且能經由水飛濺傳播。田間已廣泛存在葡萄晚腐病菌之抗藥菌系,抗Mon乳劑菌系發生頻率已高達到43~90%之間,以二林、后里地區發生抗藥性之情形最為嚴重。
Ripe rot of berries caused by Glomerella cingulata is the most prevalent disease of grape in Taiwan. Glomerella cingulata exhibited great variation in cultural characteristics but not pathgenicity. Optimum incubation temperature is 20 to 30 C. Propagules of the pathogen surviving on dormant buds and canes are the primary sources of inoculum, while those of leaves infected by mildews and rust are the secondary sources of inoculum. Isolates of ripe rot fungus isolated from Tung-Shih, Hsin-She, Erh-Lin, Ta-Tsuen, Shi-Hu, Cho-Lan and Ho-Li areas were found to have Mon-resistant strains developed in the field. The frequency or resistant strains of these fungi ranged from 43-90% in the field.