水稻细菌性基腐病株的空间分布及其抽样研究

ON THE SPATIAL DISTRIBUTION PATTERNS OF THE BACTERIAL FOOT ROT OF THE RICE IN THE FIELDS

经五种聚集度指标测定和Taylor,Iwao法检验,细菌性基腐病株在一切密度下都呈聚集型,属一般负二项分布。病株空间结构以疏松个体群形式存在,个体群间是聚集的,个体群内是随机的。个体群平均大小为0.1～0.2m^2。利用分布型参数K、α、β值,分析了病株聚集的原因;探讨了平均密度与k值的关系;确定了理论抽样数。比较几种顺序抽样方法,以平行线法效果最佳。依(?)=41.5032Pe^(1·2603)关系可由病丛率来估计病株密度。

Five aggregation indices and the methods of Taylor and lwao were used to determine the spatial distribution pattern of the bacterial foot rot of the rice.All the indices indicated that the distribution of the diseased plants was in the aggregative pattern.The parameters α,β of Iwao could be used to prove that the diseased plants in rice fields fit general negative binon(?)ial distribution. (?)y using the paraneters k,σ,β of the distribution pattern, the causes of aggregating of the diseased plants and the relati(?)n of the nean density were analysed, as a result the retical quantities of sampling were determined. Using the equation: X=4l.5032pe^(1·2603), the mean density of the diseased plant could be estimated by diseased hill rate.