福建坛紫菜赤腐病的病程及病原鉴定

于2011年10月-2012年2月,对福建省福鼎市、霞浦县、泉州市和晋江市等海区发生的坛紫菜腐烂病害进行了研究.通过观察发病特征以及镜检,详细记录了该病害的侵染过程,并在发病组织中观察到双鞭毛游动孢子以及孢子囊、雄器和藏卵器等重要结构特征,病菌形态与条斑紫菜上的紫菜腐霉相似;利用半海水玉米琼脂培养基分离提纯该病菌,命名为FM1.经感染试验证实,FM1引起的发病症状与自然海区患病紫菜的症状一致,说明FM1为致病菌.通过扩增该菌核糖体DNA ITS序列,并构建基于ITS+5.8S序列的N-J系统发育树,结果显示FM1菌株与紫菜腐霉的ITS区相似度很高,达到99%.综合形态学及ITS序列分析确定,紫菜腐霉是导致此次病烂的主要病原菌,该病原菌引起的病害称为"赤腐病".

Infection process and pathogen identification of red rot disease in Porphyra haitanensis from Fujian

Different samples of Porphyra haitanensis were collected from Fuding,Xiapu,Quanzhou and Jinjiang areas respectively in Fujian Province from October,2011 to February,2012.The development and characteristics of disease were recorded,and biflagellate zoospores,sporangium,antheridium and archegonium were found.The results of observation indicated that the symptoms of rot on Porphyra haitanensis thalli was similar to Pythilum porphyrae on Porphyra yezoensis.The mycelia strain FM1 was isolated from diseased thalli and maintained on corn-meal seawater agar(CMSA).The artificial infection experiment displayed that the experimental thalli was rotten like the thalli collected from the sea field,which meant strain FM1 was pathogen.According to analysis of the ITS rDNA(contained 5.8S),strain FM1 was highly similar to Pythilum porphyrae(99%).Combining morphology with molecular methods,this study revealed that Pythilum porphyrae was the pathogen which caused the rot of Porphyra haitanensis,the disease was called red rot disease.