中国长春瓜类白粉菌Podosphaera xanthii形态学和分子系统学研究(英文)  

Morphological and molecular characterizations of powdery mildew,Podosphaera xanthii occurring on cucurbits in Changchun AgriExpo Garden,China

作　　者：刘淑艳[1,2] 王丽兰[1] 姜文涛[1] 李玉[1] 刘炎炎[3] 

机构地区：[1]吉林农业大学食药用菌教育部工程研究中心,长春130118 [2]吉林农业大学农学院植物病理系,长春130118 [3]吉林省实验中学,长春130022

出　　处：《菌物学报》2011年第5期702-712,共11页Mycosystema

摘　　要：2009年长春农博园瓜类白粉病大发生,而且大量闭囊产生在葫芦科的四个属(葫芦属、黄瓜属、栝楼属、南瓜属)植物上。对病害发生的严重度和病情指数进行了调查,结果表明园中栽培的所有品种均为感病品种。形态学观察显示分子孢子串生,具纤维体,闭囊壳只含有一个子囊,内含8个子囊孢子,子囊顶端孔较宽(15.6-28.8μm)。有性和无性形态学特征表明该菌应属于Podosphaera xanthii。基于rDNAITS序列的分子系统学分析表明该菌与GenBank中已报道的该种在其他地区瓜类上的序列以及在其他寄主上的序列聚在一个分枝。第一次报道了在栝楼属上发现白粉菌的闭囊壳,第一次在吉林省发现西葫芦上产生闭囊壳。此外西瓜上的白粉菌虽然未产生闭囊壳,但为吉林省新记录。有关瓜类白粉菌的寄主范围、流行学、抗病品种筛选和防治有待进一步研究。In autumn of 2009,powdery mildew broke out on cucurbits in Changchun Agri-Expon,Jilin Province,China.A large number of chasmothecia of the fungus were found on plants of four genera belonging to Cucurbitaceae（Lagenaria,Cucumis,Trichosanthes and Cucurbita）.A survey was conducted to evaluate the resistance of these plants to powdery mildew based on disease incidence,disease severity and disease index.The results indicated that almost all varieties cultivated in CCAEG are susceptible to the fungus.Morphological observation shows that the conidia were produced in chains with well developed fibrosin bodies,and chasmothecia contained a single ascus with 8 ascospores and a wide apical oculus（15.6-28.8μm）.The morphological characteristics of anamorphic and teleomorphic stages reveal that this fungus belong to Podosphaera xanthii.The molecular analyses of the nucleotide sequences of the internal transcribed spacer（ITS） rDNA regions including the 5.8S rRNA gene indicate that the fungus was clustered in the clade of P.xanthii recorded from different hosts and the same host from different regions.The teleomorphs of powdery mildew on cucurbits are rarely found.It is the first report of the sexual stage found on Trichosanthes in the world,and on Cucurbita pepo in Jilin Province,China.Moreover,Watermelon Citrullus lanatus without chasmothecia was a new host record of the powdery mildew in Jilin Province.Further research on the host range,epidemiology,resistant cucurbits selection and control is required.

关 键 词：闭囊壳 形态学 分子系统 Podosphaera xanthii 白粉菌目 葫芦科 

分 类 号：S432.44[农业科学—植物病理学]