论文部分内容阅读
玉米弯孢菌叶斑病是近年来北京、河北、河南、山东、辽宁、吉林等北方玉米产区新发生的重要病害之一。其主要病原菌为弯孢菌Ｃｕｒｖｕｌａｒｉａｌｕｎａｔａ（Ｗａｌｋ）Ｂｏｅｄ．，局部地区同时存在Ｃｕｒｖｕｌａｒｉａｉｎａｅｑｕａｌｉｓ（Ｓｈｅａｒ）Ｂｏｅｄ．，但以前者为主要。弯孢菌Ｃ．ｌｕｎａｔａ生长适温为２８～３２℃，对ｐＨ适应范围广。玉米叶片浸汁可以促进分生孢子的萌发和芽管的生长。干燥条件下，病原菌在植株病残体上可以安全越冬，成为次年田间的初侵染源。病菌分生孢子形态为多态型，但单孢分离后代仍保持孢子的多态型，致病性无变化。病菌不同菌株间致病力有差异，强致病力菌株存在于北京及周边地区。人工接种鉴定１２０份玉米品种（组合）、自交系，材料间存在明显的抗性差异，抗性较好材料有农大１０８、中玉５号、高油１１５等及自交系ＣＮ９５、ＣＮ１６５等。品种抗病性随植株生长而递减。苗期抗性较好，１３叶期极为感病，因此弯孢菌叶斑病属于成株期病害。
Curvularia lunata Leaf spot is one of the most important new diseases occurred in the northern maize producing areas in Beijing, Hebei, Henan, Shandong, Liaoning and Jilin in recent years. The main pathogen is Curvularialunata (Walk) Boed. , Curvulariainaequalisis (Shear) Boed exists in some areas at the same time. , But the former is the main one. Curvularia C The optimum growth temperature of lunata is 28 ~ 32 ℃, which can adapt to a wide range of pH. Corn leaf dipping juice can promote the germination of conidia and bud tube growth. Under dry conditions, the pathogen can safely wintering on the diseased plants and become the primary source of infection in the next year. The conidial morphology of the bacteria is polymorphic, but the single spore separation progeny still maintain the spore polymorphism, pathogenicity unchanged. Pathogenicity of different strains of pathogens are different, strong virulence strains exist in Beijing and the surrounding areas. Artificial inoculation identified 120 maize varieties (combinations), inbred lines, there are significant differences between the resistance of the material, the resistance of the material Nongda 108, Zhongyu 5, high oil 115 and inbred lines CN95, CN165, etc. . Disease resistance decreased with plant growth. Seedling resistance is better, 13 leaf stage is very susceptible, Curvularia leaf spot disease belongs to the adult stage.