入侵害虫红脂大小蠹的适生区和适生寄主分析

根据发生区内的历史气象资料研究分析得出,1997年的春季干旱气候是造成1998年红脂大小蠹在山西突然暴发的原因,其中主要影响因子为春季的空气相对湿度和降水.据此利用地理信息系统软件Arcview3.2和全国305个站点的气候数据预测出该害虫在我国的气候适生区,确定目前发生区并非其最佳适生区,而是稍偏北的更加干旱地区.在这些地区如果有适宜寄主存在,一旦传入害虫将会严重发生.而目前发生区害虫种群密度则随气候转常会逐渐降低直至条件适宜再度暴发.以目前最适寄主油松为参照,对发生区及潜在区的主要针叶植物挥发物组成和比例进行相似性分析,并据此对潜在寄主进行判断,确定白皮松和云杉是除油松外较危险的侵入树种.

Preliminary Deduction of Potential Distribution and Alternative Hosts of Invasive Pest, Dendroctonus valens ( Coleoptera : Scolytidae)

According the analysis of the history record of the climate, the low humidity and fewer precipitation in spring time of 1997 in Shanxi are the main factors for the infestation of the Dendroctonus valens in 1998. With the data of 305 weather stations around the country and Areview3.2, the pest potential distribution area are supposed and shows that the climate suitable area is with more drought, north to the present infested area. Once the pests are introduced there, there will be more serious than present occurrence area. The pest population density in infested area will decrease following the regular climate recurring. The similarity analysis of monoterpene volatiles involved the attraetant of the beetles shows that Pinus bungeana and Picea asperata are more dangerous host species besides Pinus tabulaeformis in the infest area.