棉田烟粉虱成虫空间分布型与序贯抽样技术

为探讨烟粉虱成虫在长江下游的江苏沿江棉区不同棉田(Bt棉和常规棉)的种群空间分布型,指导田间取样,本研究应用5种空间分布型聚集度指标和2种回归方法(Iwao回归法及Taylor幂法则),于2008年测定和分析了烟粉虱成虫的空间分布格局.结果表明:烟粉虱成虫种群不论在Bt棉田还是在常规棉田,种群空间分布格局均一致,8月1日之前和10月3日以后,烟粉虱成虫在3个不同品种棉田中都呈均匀分布;8月1只至10月3日期间,符合聚集分布的检验标准.本文还探讨了影响其聚集的原因,并利用分布型参数确定了棉田烟粉虱成虫的理论序贯抽样数.

Spatial Distribution Pattern and Sequence Sampling Technique of Bemisia tabaci(Gennadius) Adult in Cotton Field

In order to investigate the spatial distribution patterns of Bemisia tabaci(Gennadius)adult,its population aggregating indexes in two types of cotton fields(Bt cotton and non-Bt cotton)were calculated based on the five differentkinds of related index formulae and two regression methods(Taylor's and Iwao's regression formulations).The results indi-cated that the spatial distribution patterns of B.tabaci were unanimous on Bt cotton and non-Bt cotton,and the adults were even distribution before August 1 and after October 3.The spatial distribution of adult exhibited aggregated from August 1 and October 3.In addition,the theoretical sequence sampling number was obtained from the parameters of the distribution pattern.