Biological significance of methyl eugenol which attracts males of fruit flies

甲基丁香酚（Methyl eugenol， ME）是一种对桔小实蝇（Bactrocera dorsalis, Hendel）及其复种的强引诱剂。在日本冲绳岛的孤岛上，以每月2块（4.5 × 4.5 × 0.9cm）的纤维块（每公顷10克中毒ME）为诱饵，彻底消灭了东方果蝇种群。在一年左右的时间里，每个岛上的根除工作都完成了。这与其他雄性诱饵，如cue lure和trimedlure形成对比。所以问题是为什么甲基丁香酚与其他果蝇诱饵相比如此有效。为了回答这个问题，在印度尼西亚研究了甲基丁香酚（ME）对焦小实蝇（Bactrocera carambolae, Drew & Hancock）的吸引力，焦小实蝇是B.borsalis复群的一种。大约600只新出的雄性和雌性在2天大的时候被释放到一个室外的纱笼里。筛笼内放置MEtrap、杨桃盆栽、杨桃Averrhoa carambola L.和成虫食物。男性在释放后立即开始对ME有反应。在暴露于ME期间，至少有2只雄鼠与雌鼠交配，而由于诱捕或其他因素，记录的雄鼠死亡的比例为50%至99%。这些结果表明，大多数男性在性成熟之前就对ME有反应。讨论了提高ME效率的一些因素。

Methyl eugenol (ME) is knownto be a powerful attractant to the oriental fruit fly, Bactrocera dorsalis (Hendel), and its complex of species. Monthly distribution of 2 fiber blocks (4.5 by 4.5 by 0.9cm) baited with 10g of poisoned ME per hectare resulted in complete eradication of oriental fruit fly populations on the isolated islands of Okinawa, Japan. Eradication was accomplished on each island within a year or so. This is contrasted to other male lures such as cue lure and trimedlure. So the question is why is methyl eugenol is so effective as compared with other fruit fly lures. Toanswer this question, the attractiveness of methyl eugenol (ME) to Bactrocera carambolae (Drew & Hancock), which is a species of the B.borsalis complex, was examined in Indonesia. Approximately 600 newly emerged males and females were released into an outdoor screen cage when they were 2 days old. An MEtrap, a potted carambola fruit tree, Averrhoa carambola L., and adult food were placed in the screen cage. Males began to respond to ME immediatrly after release. At least 2 males mated with females during exposure to ME,whereas>99% of the males were recorded as dead by trapping or other factors. These results indicate that most males respond to ME before they become sexually mature. some factors which may enhance the efficiency of ME were discussed.