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采用分层随机取样法调查大麦田20块,经四个聚集指标测定和 Taylor 的幂的法则、Iwao 的 m～x回归检验,明确了大麦条纹病株在田间的分布为聚集型,且聚集度随平均密度的升高而增加。比较几种顺序的抽样方法,以平行线、棋盘式,Z 形误差小,在实际调查中不宜采用对角线法。理论抽样数目可依据公式 n=43.25/X+2.75确定.大麦条纹病近年危害严重。为了能正确地估计其田间发病程度,提高病害损失预报水平,我们于1987年进行了大麦条纹病的田间分布型及抽样技术研究。现将结果报告如下:
A total of 20 barley fields were surveyed by stratified random sampling method. The results showed that the distribution of barley stripe diseased plants was aggregated in the field with four aggregation indexes and Taylor’s power law and Iwao’s m-x regression test. Increasing with increasing average density. Comparison of several sequential sampling methods to parallel lines, checkerboard, Z-shaped error is small, in the actual investigation should not be used diagonal method. The number of theoretical samples can be determined according to the formula n = 43.25 / X + 2.75 Barley stripe disease is seriously endangered in recent years. In order to correctly estimate the degree of disease in the field and improve the prediction of disease damage, we conducted a field study on the distribution and sampling techniques of barley stripe disease in 1987. The results reported below: