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研究了一种新的用于检测储藏小麦害虫感染的方法———顶空固相微萃取法（SPME），实验结果表明：利用SPME法所提取的几种常见储粮害虫（谷蠹 Rhyzopertha dominica、赤拟谷盗 Tribolium castaneum、扁谷盗 Cryptolestes ferrugineus与锈赤扁谷盗Cryptolestes pusillus）所释放的挥发性信息素可以作为粮食受害虫感染的检测指标，同时由于它们所释放的信息素量不同（谷蠹最高，其次分别是赤拟谷盗﹑扁谷盗和锈赤扁谷盗），这也直接导致了SPM E法检测灵敏度的不同，实验结果表明：在1 kg的储藏小麦中能够成功地检测出1头赤拟谷盗和1头谷蠹，而扁谷盗和锈赤扁谷盗则需要更多的数量才能够被检测出来。“,”In this study ,new method was investigated using solid phase microextraction (SPME) for detection of insect infestation in stored wheat . The results show that volatile pheromones isolated from a number of common stored grain insects ,can be used to indicate infestation . The amounts of pheromone released varied between species . Rhyzopertha dominica ( F .) was the highest volatile pheromone producer among the spe‐cies investigated ,then it was followed by Tribolium castaneum ( Herbst) ,Cryptolestes ferrugineus ( Ste‐phens) and Cryptolestes pusillus ( Schonherr) ,respectively . This resulted in different sensitivity when SPME was used for detection . A single specimen of T . castaneum and R . dominica could be successfully detected in 1 kg of wheat ,whereas more number of C .ferrugineus and C .pusillus beetles were required for detection in the same quantity of grain . Extraction period and temperature affected the sensitivity of the SPME method . Longer exposure time and higher temperature allowed more analytes to be collected . Consequently ,extraction for 4 h at 50 Cap‐peared to be the optimum condition for extracting pheromones produced by the beetles covered by this study . The method was further adjusted to be more practical and this resulted in changing the sensitivity . Detection of a single R . dominica could still be successfully achieved ,even though the time and the temper‐ature w ere reduced ,w hereas for the remaining species ,the minimum number of insects required had to be increased by about 40e60% in order to detect volatile pheromone in headspace . In conclusion , the SPME technique in detection of infestation is still required further development to be applied to the grain indus‐try . Dynamic headspace may help improve the sensitivity of technique .