ARS | Publication request: Visiting bees of cucurbita flowers (cucurbitaceae) with emphasis on the presence of peponapis fervens smith (eucerini - apidae)

Submitted to: Oecologia Australis
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 17, 2010
Publication Date: March 31, 2010
Citation: Krug, C., Alves-Dos-Santos, I., Cane, J.H. 2010. Visiting bees of cucurbita flowers (cucurbitaceae) with emphasis on the presence of peponapis fervens smith (eucerini - apidae) - Santa Catarina, Southern Brazil.. Oecologia Australis. 14(1): 128-139.

Interpretive Summary: Squashes and pumpkins are grown extensively in southern Brazil. As in the US, they require bees for pollination. In North America, we have found that at most locations, native squash bees of the genus Peponapis are responsible for most of the fruit set at commercial and garden squashes and pumpkins. Relatives of this bee are reported from southern Brazil, but their importance for pollination was not known until now. We have found Peponapis bees to abundantly visit flowers of squashes at Brazilian farms that are either organic or use their insecticides conscientiously. Just as in the US, these specialist bees have followed the cultivation of squashes beyond the boundaries of their former ranges, providing reliable, cost free pollination service to cultivate squashes and pumpkins. Brazilian farmers are being educated about this bee and its value so that more of them can implement stewardship practices that favors Peponapis bees on their farms.

Technical Abstract: Cucurbita flowers are monoecious, the male and female requiring a pollinator to transfer pollen. Bees were systematically collected as they visited flowers of three cultivated Cucurbita species grown at seven separate localities of Santa Catarina state in southern Brazil. Additionally, pantraps were used to estimate the general bee diversity at three of these locations. In total, 3,270 bees were sampled representing 50 species, with 3.153 bees (24 species) counted during censuses on the flowers and 117 individuals of 30 species in the pantraps. The most abundant bee species was Apis melifera (32%) followed by the squash specialist, Peponapis fervens (25%). This latter species was present at five of the seven study localities. It was the most abundant bee at Cucurbita in three of these places. Nests of P. fervens were found in two localities. Each vertical nest was excavated in clay soil and occupied by a single female. Pollen analyses of the larval provision revealed that the females collect pollen only on squash flowers (100% Cucurbita pollen grains) confirming its specialization. The presence of this bee species in the study area seems to be related to the good environmental condition and stewardship by the farmers, especially their careful use of insecticides.