Abstract: To determine whether the resistance of plant to powdery mildew is related to the leaf surface structure or anatomical structure,three Poa pratensis cultivars were inoculated with Erysipelas Graminis for disease investigation. The stomata,mastoid process,surface structure and anatomical structure of leaves were measured by SEM and paraffin section combination. The results showed that:the incidence,disease index and resistance to powdery mildew of different Kentucky bluegrass varieties were different,and the resistance was divided into:mid-resistance (Moderate disease resistance,MR) in Poa pratensis ‘Midnight Ⅱ’,mid-sense (Moderate susceptibility,MS) in Poa pratensis ‘All Spring’，extreme sense (Easy susceptibility,ES) in Poa pratensis ‘Ever Glade’. The stomata length,stomata length-width ratio of different bluegrass varieties were negatively correlated with powdery mildew resistance;While mastoid density,mastoid width,upper and lower epidermis thickness were positively correlated with powdery mildew resistance. The thickness of the epidermis on the leaves of disease-resistant varieties of Kentucky bluegrass was thick,and the papillae distributed on the epidermis was dense and large,which were the structures of varieties that are resistant to powdery mildew infection.

Key words: Poa pratensis, Leaf surface structure, Anatomical structure, Powdery mildew

摘要： 为了探究叶片表面结构和解剖结构与白粉病的抗性的关系，以3个草地早熟禾（Poa pratensis L.）品种为试验材料，接种禾布氏白粉病菌（Erysiphe graminis DC.ex Merat）进行病情调查，采用扫描电镜法和石蜡切片法相结合，测定叶片的气孔、乳突、表面结构和解剖结构等指标。结果表明：不同草地早熟禾品种的发病率、病情指数和对白粉病的抗性存在差异，抗性划分为：‘午夜2号’表现为中抗（Moderate disease resistance，MR），‘四季青’表现为中感（Moderate susceptibility，MS），‘超级哥来德’表现为极感（Easy susceptibility，ES）；不同草地早熟禾品种气孔长度、气孔长宽比与白粉病抗性均呈负相关；乳突密度、乳突宽度、叶片上下表皮厚度三者与白粉病抗性均呈正相关；草地早熟禾抗病品种叶片上下表皮厚度大，且表皮上分布的乳突密而大，是抗性品种具备的防御白粉病菌侵染的结构。

关键词: 草地早熟禾, 叶表结构, 解剖结构, 白粉病