对进境高粱种子中高粱炭疽病菌疏纹刺盘孢的检疫

Quarantine identification of Colletotrichum sublineola on imported Sorghum bicolor seeds

从一批进境的美国高粱种子样品中分离得到一株与疏纹刺盘孢Colletotrichum sublineola形态相似的菌株6222-1。经形态学观察发现该菌产生大量镰状或梭形分生孢子,在菌丝末端形成膨大的附着胞。经多位点基因(ITS、GAPDH、CHS-1、HIS3、ACT、TUB2)系统发育分析,发现该菌株与C.sublineola模式菌株聚集在同一个分支上,支持率达到100%。经病原菌接种高粱幼苗叶部,引起典型的炭疽病症状。根据上述研究结果,确认该菌株为疏纹刺盘孢。这是我国首次截获该危险性病原真菌。

A fungal isolate 6222-2 was generated from the imported sorghum seeds shipped from America. It wasmorphologically similar to Colletotrichum sublineola producing falcate or fusiform conidia and hyphopodial appressoria on PDAmedium. The multi-locus （ITS, GAPDH, CHS-1, HIS3, ACT and TUB2） phylogenetic analysis revealed that the isolate was clusteredwithin the type strain of C. sublineola. The pathogenicity test revealed that it infected sorghum leaves by forming typicalanthracnose symptom. Based on the above results the isolate was identified as C. sublineolo. This is the first interception reportof C. sublineola from the imported American sorghum seeds by Chinese quarantine agency.