小麦白粉病不同分级标准的比较研究

Comparative Studies on Several Seriousness Gradation Standards or Wheat Powdery Mildew

本文对４种常用的以株为单位的小麦白粉病成株期分级标准的比较研究表明：４种分级标准的病情指数调查值问，除在病情指数低于６．３时外，均存在显著差异。进一步统计分析表明：不同分级标准的病情指数调查值间分别呈线性关系或幂函数关系。利用数学模型可使按不同标准调查、计算的病指数据相互转换并得以统一，便于各地资料的交流、比较和利用。

The comparative studies on the 4 commonly used seriousness gradation standards of wheat powdery mildew were carried out through field investigations and statistical analyses. The relationships among the disease indices (DI's) of the 4 standards were studied, and the mathematical models of these relationships as well as disease index transformation models were built respectively.