小蜂对杨圆蚧的趋性及杨圆蚧挥发物分析

采用四臂式嗅觉仪测定了长棒四节蚜小蜂和黄胸扑虱蚜小蜂对杨圆蚧1龄固定若虫的虫体、介壳、虫体与介壳复合体的趋性。结果表明，介壳和虫体与介壳复合体对两种小蜂具有较强的吸引力。两种小蜂对气味源的剂量都比较敏感。采用敢相色谱－质谱联机分析方法，分析了杨圆蚧1龄固定若虫虫体及介壳所释放的挥发性物质的成分和各组分所占比例，分析表明，虫体和介壳中释放出的挥发性物质均含有9个组分，但这9个组分在虫体和介壳挥发物中的比例略有变异。

The Taxis of Chalcid Parasitoids to Their Host and Analysis of the Volatile from Fixed First Instar Nymphae of Quadraspidiotus gigas (Thiem & Gerneck)

Four armed olfactory instrument was used to test the taxis of Encarsia gigas (Tshumakova) and Pteroptrix longgiclava (Girault) to the body of fixed first instar nymphae of Quadraspidiotus gigas (Thiem & Gerneck), or to their scale, or to the combination of their body and scale. The results showed that scale and the combination of scale and body were more attractive to those two kinds of chalcid parasitoids than that of the body of fixed first instar nymphae. Those two parasitoids were sensitive to the dosage of the odor resources. The chemical components of the volatile from the body or scales of first instar nymphae of Quadraspidiotus gigas (Thiem & Gerneck) have been analyzed using GC-MS method. The ratio of those compounds contained in the volatile was detected at the same time. Analyses show that both volatiles produced by either body or scales is consisted of 9 compounds. The proportions of those ingredients composing these volatile are slightly different.