玉米弯孢菌叶斑病传播梯度模型

Spread gradient model of leaf spot disease (Curvularia lunata) in maize

根据植物病害流行学原理 ,采用人工接种方法 ,在田间造成玉米弯孢菌叶斑病不同的发病梯度 ,分析连续 2年玉米弯孢菌叶斑病传播动态。利用SPSS统计软件构建了此病害的传播梯度模型 ,结果表明指数模型是沈阳地区玉米弯孢菌叶斑病传播梯度的最佳模型。接种 2个月 ,掖单 13玉米弯孢菌叶斑病传播梯度最佳模型是x =9.6 0 6×EXP(- 0 .2 82 9×d) ,海试 16最佳模型是x =7.15 4×EXP(- 0 .2 35 1×d) (x:病情指数 ,d :距菌源中心的距离 )。预测玉米弯孢菌叶斑病在 2个月最远传播距离为 2 8m ;传播速度为 0 .4～ 0 .5m/d。

According to the principles of plant disease epidemiology, the dynamics of spread of leaf spot disease in two successive years was studied by artificial inoculation, which causes the disease gradient of Curvularia lunata in maize in experi_ mental fields. The disease gradient model, which was established using the software for SPSS, shows that exponential model is the optimum one in Shenyang region. During the maize growing season of two months, the results show that x=9.606×EXP(-0.2829×d) is the optimum model for the maize cultivar's Yeddan 13, and x=7.154×EXP(-0.2351×d) for cultivar's Haishi 16. The furthest spread distance of the disease is about 28 m within two months of the growth season, and the velocity of spread of the disease between 0.4-0.5 m/d.