AGGREGATION PHEROMONES OF DROSOPHILA IMMIGRANS, D-PHALERATA, AND D-SUBOBSCURA

Aggregation pheromones of Drosophila immigrans, D. phalerata and D. su bobscura were demonstrated by testing attraction of adult flies to hex ane extracts of the flies in a windtunnel bioassay. Extracts of adult males of all species attracted conspecific males and females. However, D. subobscura flies were attracted only when the extract was applied on food. CC-MS analysis identified (Z)-11-octadecenyl acetate (cVA) in the extracts of adult male D. immigrans and D. phalerata. Both specie s were attracted to synthetic cVA. Male and female D. subobscura produ ced 5,9-pentacosadiene, 5-pentacosene, 2-methylhexacosene and 5,9-hept acosadiene, while only male D. subobscura produced (Z)-5-tricosene and minor amounts of cVA.