Queensland fruit fly is one of the most economically important horticultural pests in Australia. Sterile insect technique (SIT) is now being reconsidered and upscaled to combat this pest so reliable discrimination of released sterile Q-flies from wild flies in monitoring traps is important for effective SIT operations. Stable isotopes provide a permanent chemical marker to discriminate sterile and wild flies when dye marking is unclear. In this study, we compared the isotopic ratios of carbon and nitrogen between Q-flies reared on different larval diets and wild flies collected from diverse locations in Australia and New Caledonia. Finally, we conducted a release–recapture study to corroborate differences in stable isotope C and N ratios in laboratory-reared and wild Q-flies. The δ¹⁵N values obtained from wild and laboratory Q-flies showed high variability that is likely related to the food source of the larval and/or adult stage and do not offer an effective means to discriminate between sterile and wild Q-flies. The δ¹³C values of examined wild Q-flies ranged from − 27.46 to − 24.37‰ VPDB, whereas those from laboratory-reared, released and recaptured Q-flies ranged from − 25.73 to − 19.26‰ VPDB. Differences in δ¹³C values resulted in 100% correct classification of wild flies and 96.88% correct classification of released flies. Measurements of intrinsic δ¹³C values offer a precise tool to discriminate between sterile and wild Q-flies in SIT programs, regardless of the composition of the larval or adult pre-release diets.

昆士兰果蝇是澳大利亚最经济重要的园艺害虫之一。目前正在考虑对不育昆虫技术（SIT）进行改进并扩大规模，以对抗这种害虫，因此在监控诱集装置中可靠区分来自野蝇的已释放不育Q蝇对于有效的SIT操作至关重要。当染料标记不清楚时，稳定的同位素提供了永久性的化学标记，可以区分不育和野生果蝇。在这项研究中，我们比较了不同幼虫饮食和从澳大利亚和新喀里多尼亚不同地点采集的野生果蝇饲养的Q蝇之间碳和氮的同位素比。最后，我们进行了释放-捕获研究，以证实实验室饲养和野生Q-蝇中稳定同位素C和N比率的差异。该δ ¹⁵从野生Q蝇和实验室Q蝇获得的N值显示出较高的变异性，这很可能与幼虫和/或成年阶段的食物来源有关，并且没有提供区分无菌Q蝇和野生Q蝇的有效手段。该δ ¹³检查野生Q-苍蝇的C值范围为- 27.46至- 24.37‰VPDB，而那些从实验室饲养，释放并收复了Q-苍蝇范围- 25.73至- 19.26‰VPDB。在δ差异^13个C值导致野生苍蝇和蝇公布的96.88％的正确分类的100％正确分类。固有δ测量¹³ C值提供无菌的和野生Q-果蝇之间的精确工具来判别在SIT方案，无论幼虫或成虫预发布饲料的组合物。