甜瓜白粉病病原菌鉴定及抗病种质资源筛选

Identification of Melon Powdery Mildew Pathogen and Screening of Germplasm Resources Resistant to Powdery Mildew

三亚是海南甜瓜的重要产区,也是甜瓜白粉病的高发区。利用镜检法、分子生物学方法以及国际通用的13个标准鉴别寄主对三亚甜瓜试验基地自然发病的白粉病病原菌进行生理小种鉴定,并从自主选育的第4代甜瓜种质资源中挑选30个材料进行白粉病苗期抗病性鉴定和筛选。结果表明,通过病原菌孢子的形态特征分析、ITS序列比对以及13个标准寄主对白粉病病原菌接种的感抗反应,综合判定该病原菌为瓜单囊壳白粉菌(Podosphaera xanthii)的Race 2France生理小种。另外,从30份厚皮甜瓜材料中筛选出对白粉病免疫的材料2份(22-7-2、22-16-1),对白粉病高抗的材料3份(06-4-1、14-8-1、23-8-1);2份免疫材料均为黄皮、椭圆、网纹类型,3份高抗材料均为网纹类型。

Sanya city is an important producing area of Hainan Melon,and also a high-incidence area of melon powdery mildew.This study identified the physiological race of powdery mildew pathogen naturally occurring at Sanya melon test base by using microscopic,molecular biology methods,and 13 internationally recognized standard identification hosts.Besides,the study chose 30 materials from the self-selected 4th generation melon germplasm resources for identification and screening of resistance to powdery mildew during seedling stage.Results showed that through analysis on morphological characteristics of pathogenic spores,bacteria ITS sequences alignment,and inductive reaction of 13 standard hosts to powdery mildew pathogen inoculation,the pathogen was determined to be the Race 2France of Podosphaera xanthii.Additionally,2 materials(22-7-2,22-16-1)were found to be immune to powdery mildew out of 30 thick-skinned melons;and 3 were found to be highly resistant to powdery mildew(06-4-1,14-8-1 and 23-8-1).The 2 immune materials were all of yellow-skinned,elliptical,and reticulated types.While,the 3 were all high-resistant materials of reticulate type.