葡萄品种霜霉病抗性的田间自然鉴定

葡萄霜霉病(Downymildew)是发生最为广泛、危害最为严重的真菌病害之一。于葡萄霜霉病发病盛期,对在陕西省杨凌区新引进栽培的不同葡萄新品种霜霉病抗性进行田间自然鉴定,摸清不同葡萄品种抗病性,为葡萄霜霉病的田间防控和葡萄抗病育种提供理论依据。通过对新引进的38个葡萄品种叶片的田间发病情况统计,并对霜霉病的抗病指数和病叶率进行常规分析和聚类分析。结果显示,在调查的38个葡萄品种中,6个品种表现为高抗,病情指数为4.47;6个品种表现为抗病,病情指数为20.00;18个品种表现为感病,病情指数为34.47;8个品种表现为高感,病情指数为62.00。受霜霉病的感染,葡萄的病叶率达82.90%,且随着抗病等级的降低,叶片病害等级也随之增加。综上所述,不同品系葡萄对霜霉病的抗病等级为:山欧杂交种山葡萄欧美杂交种欧亚种,且不同葡萄品种间的抗病性存在显著差异。

Field Identification of Disease Resistance for Downy Mildew in Grape Varieties

Downy mildew is one of the most prevalent and serious fungal diseases in grapevine (Vitis. spp).The downy mildew resistance of a total of 38 genotypes which were newly introduced to Yangling in Shaanxi province were identified for making clear the resistances to different varieties under natural condition during the full incidence period.The findings not only understood more about the field management of grape downy mildew, but also laid the foundation for breeding grapevines resistant to downy mildew in the future. We collected the field downy mildew incidence under natural condition and the disease index. In addition,the diseased incidence of downy mildew was also analyzed routinely and clustered. Among the investigated varieties, there were 6 high-resistant grape varieties, 6 disease-resistant grape varieties, 18 susceptible grape varieties and 8 high-susceptible grape varieties; the disease index was 4.47, 20.00, 34.47, 62.00, respectively. We found that the rate of diseased leaves was 82.90%. Furthermore, the leaf disease level was increased with the decrease of the disease resistance level. All in all, the grade of downy mildew resistance is V. amurensis.×V. vinifera.>V. amurensis.>V. vinifera.×V. labrusca.>V. vinifera., and there are significant differences in disease resistance among these grapevine varieties.