桉树枝瘿姬小蜂空间分布格局

桉树枝瘿姬小蜂（Leptocybe invasa Fisher＆La Salle）是近年来发现的一种重要的检疫性有害生物.为了研究该虫在桉树林内的空间分布格局,2011年6月在广西北海对桉树无性系DH201-2上的虫瘿和成虫进行了详细的调查研究,应用扩散系数等7种指标对其空间分布进行了测定.结果表明：该虫在桉树林中分布格局为聚集分布,叶脉、叶柄、茎上的虫瘿和成虫的聚集原因是依靠环境因素决定的,柄脉上虫瘿的聚集主要是其本身的聚集习性和环境因素共同作用引起.在此基础上,建立该虫林间理论抽样数公式,给出了不同虫口密度以及不同误差要求的最适抽样数.

Spatial Distribution Pattern of Leptocybe invasa Fisher et La Salle

Leptocybe invasa Fisher ＆ La Salle was one of main quarantine pests. In order to study the spa- tial distribution pattern of the pest in Eucalyptus forests, galls and adults in Eucalyptus clone DH201-2 were investigated detailedly in Beihai of Guangxi in June 2011. Seven indices such as diffusion coefficient were applied to test the spatial distribution. The results showed that the spatial distribution pattern was assembly distribution. The aggregation of galls and adults in leaf vein, petiole, and stem was caused by environment. The aggregation of galls in leaf vein-petiole was caused by behavior and environment. Based on this distribution pattern, the optimum theoretical sampling numbers according to different population densities and errors were gave.