AN UPDATE ON POLLINATION AND RELATIVE ATTRACTION OF WILD FRUIT FLY MALES TO DACINIPHILOUS BULBOPHYLLUM CHEIRI SUBSPECIES CHEIRI (ORCHIDACEAE) FLOWERS

Abstract

The fruit fly orchid, Bulbophyllum cheiri subspecies cheiri is found in coastal vegetation and lowland tropical rain forest in Southeast Asia. Its flowers attract males of the Oriental fruit fly which are strongly attracted to methyl eugenol (ME) that is found in >450 plant species. This study shows that wild Oriental fruit fly males were not attracted to the non-resupinate fruit fly orchid flower via color nor shape. Instead, male flies were attracted solely to the flowers, when covered by cotton or synthetic fabric, via floral volatiles. Natural pollinarium removal and pollinia deposition were observed; and were exclusively performed by the oriental fruit fly males. Comparison of fly attraction to a day-one or day-two (d-1 or d-2) flower versus a Steiner trap, baited with 6 g commercial ME set 20 m apart in the field showed a significant difference between d-1 and d-2 flowers with ca. 29 and 18% of total captured flies per day, respectively.