一种可用于桔小实蝇表皮碳氢化合物分析的固体进样技术

A solid injection technique suitable for cuticular hydrocarbon analysis of Bactrocera dorsalis( Diptera: Tephritidae)

【目的】利用表皮碳氢化合物进行昆虫鉴定是目前昆虫分类学中非常活跃的研究方向之一。昆虫表皮碳氢化合物的液体浸提及进样技术是GC-MS常规的进样方法之一,随着现代技术的发展,固体进样也被广泛地用于昆虫表皮碳氢化合物的鉴定及昆虫的分类与进化分析。本研究探索利用固体进样法开展实蝇表皮碳氢化合物的提取与分析,探索并获得简便可行的取样与进样技术,为检疫性实蝇的快速鉴定提供新方法。【方法】以桔小实蝇Bactrocera dorsalis（Hendel）成虫为材料,采用固体进样与液体浸提进样方法,开展实蝇表皮碳氢化合物组成成分鉴定与分析;比较获得桔小实蝇成虫取样部位,并分析标本保存时间对桔小实蝇表皮碳氢化合物组成的影响。【结果】利用固体进样技术获得的桔小实蝇翅表皮碳氢化合物种类（39）较液体进样的（36）略多,且翅和中足的表皮碳氢化合物含量分别为0.18~23.37和0.03~4.13 ng/μg,极显著地高于用液体进样法检测到相同部位的化合物含量（分别为0.05~3.93和0.01~0.68 ng/μg）（P〈0.01）,而且前者的检测灵敏度是后者的1.7~10.8倍;同时,翅样品的表皮碳氢化合物含量显著地高于足中的含量（P〈0.01）。利用固体进样获得的桔小实蝇成虫翅、足或胸部的表皮碳氢化合物图谱与对照处理所得图谱相似。干燥保存30 d的桔小实蝇翅的碳氢化合物的种类及含量与新鲜标本（保存0 d）无显著性差异（P〉0.05）;但保存30,60和150 d标本的碳氢化合物存在显著差异（P〈0.05）,主要是含量的差异。【结论】研究表明,利用固体进样检测昆虫表皮碳氢化合物的灵敏度较高,而且桔小实蝇成虫的主要表皮碳氢化合物种类较稳定,因此可以作为我国口岸检疫性实蝇表皮碳氢化合物获取与分析的一种新方法,而且检测中翅是固体进样的较合适取样部位。

【Aim 】 Insect cuticular hydrocarbon profiles have been actively studied in insect chemotaxonomy. Liquid injection with solvent is commonly used technique for extraction and sample introduction. This study explored an easier and simpler extraction and sample introduction technique using solid injection. We discussed the feasibility of the technique in rapid identification of fruit flies. 【Methods】The cuticular hydrocarbon profiles of adult Bactrocera dorsalis（ Hendel） were compared using thermal separation probe（ TSP）（ a solid phase injection device） and a liquid injection technique. Then the cuticular hydrocarbon profiles from head,thorax,abdomen,forewings,and legs of the fruit fly using solid injection were compared with those from the whole body extracts using liquid injection. Finally the cuticular profiles of the adult specimen preserved for various time periods were analyzed. 【Results】The results showed that cuticular hydrocarbon components obtained from adult wing using solid injection（ 39components） were higher than those obtained using liquid injection（ 36 components）. The quantities of cuticular hydrocarbons from both wings and legs obtained using solid injection were 0. 18- 23. 37 and0. 03- 4. 13 ng / μg,respectively. They were extremely significantly higher than those obtained using liquid injection（ 0. 05- 3. 93 and 0. 01- 0. 68 ng / μg from wings and legs,respectively）（ P〈0. 01）.The hydrocarbon amount from the wings was significantly higher than that from the legs（ P〈0. 01）. The detection sensitivity for cuticular hydrocarbon analysis using solid injection was 1. 7- 10. 8 times as high as that obtained using liquid injection. The cuticular hydrocarbon composition of wings,legs,and thorax using solid injection was similar to that of whole body using liquid injection. Specimens preserved for 30 d in desiccator were not significantly different from fresh specimens in the composition and content of wing hydrocarbons（ P〉0. 05）. However,the compositions of wing hydrocarbons from specimens preserved for30,60 and 150 d were significantly different（ P〈0. 05）. 【Conclusion】Solid injection technique can be used as an alternative method for cuticular hydrocarbon analysis of B. dorsalis,and adult wing is a good sampling part for the solid injection method. It is more sensitive than liquid injection method. The technique provides the technical basis for rapid identification of fruit flies during border inspection and quarantine.