春小麦白粉病田间分布型及抽样技术研究

Study on Field Distribution Pattern and Sampling Techniqueof Spring Wheat Powdery Mildew

在春小麦白粉病发病初期,采用不同抽样方法调查小麦白粉病的病株率,运用4种空间分布型聚集指标和Iwao回归分析法、Taylor幂法则对春小麦白粉病病株的田间分布型进行测定。结果表明,棋盘式取样法更适用于发病初期春小麦白粉病的田间调查,准确度更高。春小麦白粉病发病初期的田间分布型为均匀分布,田间分布的基本成分为相互排斥的个体。根据平均拥挤度(M*)与发病级别均值(m)之间的Iwao回归关系,建立春小麦白粉病田间最适抽样模型为N=t^(2)(0.836/m-0.018)/D^(2)及序贯抽样模型T(1,2)=0.8 n±1.589√n。

In the early stage of spring wheat powdery mildew,the incidence of powdery mildew was investigated by different sampling methods,and the field distribution pattern of spring wheat powdery mildew was determined by using four spatial distribution aggregation indexes,Iwao regression analysis and Taylor power law.The results showed that the chessboard sampling method was more suitable for the field investigation of spring wheat powdery mildew at the beginning of the disease,and its accuracy was higher.The field distribution pattern of spring wheat powdery mildew at the early stage was even,and the basic components of field distribution were mutually exclusive individuals.According to the Iwao regression relationship between the average crowding degree(M*)and the mean disease level(m),the best sampling model for spring wheat powdery mildew in the field was N=t^(2)(0.836/m-0.018)/D^(2) and the sequential sampling model T(1,2)=0.8 n±1.589√n.