Studies on Ecological Functions of Tephritid Fruit Fly Attractants

在任何一种重要的经济害虫中，叶蝉科的果蝇造成的经济损失是最大的。桔小实蝇(Dacus Dorsalis)的甲基丁香酚和瓜实蝇(Dacus Cucurbitae)的特异雄引诱剂已被用作有效的质量诱捕剂和种群监控剂。然而，这种特定诱饵对雄性斑潜蝇的生物学意义尚不清楚。这项研究是为了阐明这些果蝇引诱剂的生态功能。一些植物含有甲基丁香酚作为精油。雄性桔小实蝇访问植物，以植物组织为食，以获得必要的成分。在野生雄性的直肠腺中发现了两种与甲基丁香酚密切相关的苯丙烷类化合物，它们在求偶期间排放到空气中，表明该成分具有信息素功能。此外，还利用捕食性动物测定了变态功能。天南星科植物白蜡树的花吸引桔梗的一些亚种，但不含显著数量的甲基丁香酚。取而代之的是，从这种花中鉴定出了其他几种相关的化合物。金莲花散发出强烈的香味，吸引了葫芦科石斛的雄性。经鉴定，引诱剂为4-(苯基苯基)-2-丁酮。雄蝇选择性地将这种化合物积聚到直肠腺中，这表明它在求偶过程中发挥了信息素的作用。

Fruit flies of the family Tephritidae cause some of the greatest economic losses of any of the economically important pest insects. Specific male attractants, methyl eugenol for the oriental fruit fly (Dacus dorsalis) and cuelure for the melon fly (Dacus cucurbitae), have been used as the powerful mass trapping agents and the population-monitoring bates in the eradication program of these insects. However, the biological significance of such specific attraction of the lures for the male dacine flies has not yet been clarified. This study has been undertaken to clarify the ecological function of these fruit fly attractants.A number of plants contain methyl eugenol as the essential oil. D. dorsalis males visit the plants, feed on the plant tissues to acquire the essential component. Two phenylpropanoid compounds which are closely related to methyl eugenol were found in the rectal glands of wild males, which were emitted to the air during courtship period, suggesting any pheromonal function of the component. Allomonal function was also determined using predatory animals. Flowers of Spathiphyllum communatum (Araceae) attract some subspecies of D. dorsalis, but has no significant quantities of methyl eugenol. Instead, several other related compounds were indentified from the flower.Flowers of Dendrobium superbum emit fragrance which strongly attracts D. cucurbitae males. The attractant chemical was identified as 4-(phydroxyphenyl)-2-butanone. The male fly selectively accumulated the compound into the rectal glands, suggesting a pheromonal role during courtship.