摘要
对秋甜玉米田的斜纹夜蛾不同发生密度田块调查 ,取得了 7组样本资料 ,运用聚集度指标法、Iwao法和Taylor法等对其空间分布型进行测定检验 ,结果表明斜纹夜蛾幼虫呈聚集分布 ,其聚集原因经Blackith种群聚集均数测定 ,当m <3 .2 60 4时 ,其聚集是由于某些环境如气侯、土壤湿度、植株生长状况等所致 ;当m >3 .2 60 4时 ,其聚集是由于害虫本身的群集行为与环境条件综合影响所致。在此基础上 ,通过几种抽样方式比较以五点式为最佳 ,并提出了最佳理论抽样数和最佳序贯抽样模型 :N =1 D2 (3 .8981 m +0 .75 0 3 ) ,To(n) =0 .5n± 2 .865n。
Three methods of aggregated indices and Iwao's way (regressive relation by M*-m) and power law of Taylor were used to test the spatial disritbution pattern of Prodenia litura in the vegetable corn field. The results showed that the larvae of P. litura belong to the pattern of aggregation distribution. It was tested by Blackith,s method,when m<3.2604 their aggregation caused by some environmental factors such as elimate and soil humidity and growth and so on ,when m>3.2604 their aggregation caused by their mass conduct Based on this distribution pattern a suitable sampling mode has been provided ,the errors of several sampling methods for sampling larval population in the field were compared,and the five points method was best .The model for determining the optimun theoretical sampling number and the optimun sequential sampling are proposed .The model are as follows: N=1/D2(3.8981/m+0.7503)and T-o(n)=0.5n±2.865n.
出处
《昆虫知识》
CSCD
北大核心
2004年第6期585-588,共4页
Entomological Knowledge
基金
浙江省重点课题资助项目 (2 0 0 3C2 2 0 2 7)
临海市重点科技项目 (0 3412 )
