Pantnagar Journal of Research

Abstract

Sponge gourd, Luffa cylindrica (L.) Roem. is a common vegetable crop possessing hermaphrodite flowers. Investigation was carried out to study the diversity of flower visiting insects, abundance and foraging behaviour of insect pollinators, floral attributes like anthesis, flower size, anther dehiscence, flower sex ratio and the mechanism of pollen transfer from staminate to the pistillate flowers on the sponge gourd. A total of 23 species from four insect orders, Hymenoptera, Lepidoptera, Coleoptera and Diptera were recorded from the sponge gourd flowers with hymenopteran pollinators contributing to 17 of such species. Across the 11 species considered as pollinators, 1.67 insects visited 50 flowers per 5 minutes, exhibiting their peak activity during 8.30 to 10.30 am. The bee species, Tetragonula iridipennis, Apis dorsata, A. cerana and A. mellifera were recorded as more frequent visitors with a mean abundance of 5.79, 3.84, 2.41 and 1.98 bees/50 flowers/5 min, respectively. Further, Xylocopa iridipennis visited maximum number of Luffa flowers (range: 12-15) with minimum time spent on a single sitting (5-27 seconds). Whereas, the stingless bee, T. iridipennis was found to be visiting the least number of flowers (range: 2-5) in a single visit while spending maximum time on a single flower (110-170 seconds). Significance of commercial cultivation of this summer vegetable crop for beekeeping has also been discussed.