滇黄精炭疽病菌的初步鉴定及其对3种杀菌剂的敏感性

对2019年采集自云南省3个滇黄精产区的炭疽病菌进行形态学及ITS序列分子鉴定，并采用菌丝生长速率法，测定了40株黄精炭疽病菌对氟啶胺、咪鲜胺和苯醚甲环唑的敏感性。结果表明:从滇黄精炭疽病病叶上分离得到的40株炭疽病菌可能分别属于炭疽菌属中的胶孢炭疽菌Colletotrichum gloeosporioides、果生炭疽菌C. fructicola、博宁炭疽菌C. boninense和尖孢炭疽菌C. acutatum，其中果生炭疽菌29株，占总分离菌株的72.5%，为优势病原菌。3种杀菌剂对 40 株供试菌株的菌丝生长有明显的抑制作用，氟啶胺、咪鲜胺和苯醚甲环唑的EC₅₀ 值分别介于0.028~0.53 mg/L、0.018~2.69 mg/L 和 0.158~2.57 mg/L 之间，即供试菌株对氟啶胺的敏感性高于其对咪鲜胺和苯醚甲环唑的敏感性。目前，3个滇黄精产区的炭疽病菌尚未对氟啶胺、咪鲜胺和苯醚甲环唑产生抗药性。

Preliminary identification of the pathogen causing Polygonatum kingianum anthracnose and their sensitivities to three fungicides

A total of 40 Colletotrichum strains causing anthracnose on Polygonatum kingianum were isolated and identified by morphology and ITS sequence in 2019. They were collected from three producing regions in Yunnan Province. Their sensitivities to fluazinam, prochloraz and difenoconazole were tested using the mycelium growth rate method. The results showed that all the 40 strains isolated from P. kingianum diseased leaves might belong to genus of Colletotrichum, i.c. C. gloeosporioides, C. fructicola, C. boninense and C. acutatum. Among them, 29 strains belong to C. fructicola, accounting for 72.5% of the total isolated strains. Fungicide sensitivity tests indicated that fluazinam, prochloraz and difenoconazole showed strong antifungal activities against the growth of all the tested strains. The EC₅₀ values of fluazinam, prochloraz and difenoconazole to all tested strains were in the range of 0.028-0.53 mg/L, 0.018-2.69 mg/L and 0.158-2.57 mg/L, respectively. The sensitivities of all strains to fluazinam were higher than those to prochloraz and difenoconazole. No resistant strains to fluazinam, prochloraz and difenoconazole were found in those three producing regions of Yunnan Province.