抗叶斑病玉米种质资源的筛选及抗病机制初探

Screening of Germplasm Resources with Resistance to Leaf Spot and Preliminary Exploration on Its Disease Resistance Mechanism

[目的]了解不同玉米品种对弯孢菌叶斑病的抗性。[方法]以掖单22（感病）为对照，通过室内和田间接菌试验，研究金海5号、郑单958等11个品种对弯孢菌叶斑病的抗性差异。[结果]室内接菌条件下，接菌3d后玉米开始发病，5—10d内病情发展迅速，10d后病情趋于稳定；接菌10d时，掖单22和金海5号最感病，农大108最抗病。田间接菌条件下，玉米发病症状较室内接菌严重，大部分品种表现为中感和感病，仅鲁单981、LN3和农大108表现为中抗，接菌10d后病情指数最高达76．8％，较室内接菌高36．3％。[结论]对弯孢菌叶斑病抗性较好的品种为LN3和农大108，抗性较差的品种为掖单22和金海5号。

[Objective] The aim was to understand the disease resistance of maize varieties to Curvularia leaf spot. [Method] With Yedan 22 （suscepti- ble） as CK, through indoor and field inoculation test, the resistances of 11 maize varieties such as Jinhai 5, Zhengdan 958 etc. to Curvularia leaf spot were studied. [Result] Under indoor inoculation condition, maize started to infect disease after 3 d of inoculation, the disease developed quickly within 5-10 d of inoculation and the disease tended to be stable after 10 d of inoculation. After 10 d of inoculation, the disease of Yedan 22 and Jinhai 5 were the most seriously, and that of Nongda 108 was the most slightly. Under field inoculation condition, the disease symptom of maize was more serious than that in indoor inoculation, most varieties showed moderate infection and infection and only Ludan 981, LN3 and Nongda 108 showed moderate resistance. After 10 d of inoculation, the highest disease index was 76.8%, being 36.3% higher than that of indoor inoculation. [ Conclusion] The resistances of LN3 and Nongda 108 to Curvularia leaf spot were better, and those of Yedan 22 and Jinhai 5 to Curvularia leaf spot were worse.