Attraction of Male <i>Bactrocera dorsalis</i>（Diptera: Tephritidae）to Fresh Fruit Volatiles of <i>Terminalia catappa</i>（Myrtales: Combretaceae）

Terminalia catappa L. （Myrtales: Combretaceae） is one of the main hosts of the oriental fruit fly, Bactrocera dorsalis（Hendel）（Diptera: Tephritidae）, the fruit of which emits methyl eugenol（ME）, which attracts male B. dorsalis. In this study, the attractiveness of fresh fruit to adult male flies was investigated. In laboratory assays using small cages and transparent traps, a significantly larger number of males were attracted to mature yellow fruits（6.78±2.56 flies）than to immature green fruits（1.06±1.77 flies）； however, similar results were observed in small cage assays with opaque white traps. These results suggest that visual information, such as fruit color, does not primarily influence the attractiveness of the fruit to male oriental fruit flies. On the other hand, additional experiments using a wind tunnel showed that the attraction of the male flies to ME was significantly reduced by 24 h exposure of the male flies to yellow fruit, but the attraction recovered in 1 week. These results suggest that the behavior of male B. dorsalis can be affected by consumption of T. catappa fruit.