Submitted to: Blueberry Research Extension North American Workers Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: April 15, 2003
Publication Date: July 27, 2004
Citation: Sampson, B.J., Stringer, S.J., Cane, J.H., Spiers, J.M. 2004. Screen House Evaluations of a Blue Orchard Bee Osmia ribifloris (Hymenoptera: apidae) as a Supplemental Pollinator for Southeastern Blueberries. Blueberry Research Extension North American Workers Conference Proceedings. 3(15):381-392. Interpretive Summary: Osmia ribifloris is a docile, wild bee that is being domesticated as a commercial blueberry pollinator. Larvae and pupae of this bee develop normally in Mississippi, and adults can forage under weather conditions considered to be less clement to honey bees. Osmia ribifloris was an efficient blueberry pollinator, as fruit were set by two-thirds of the flowers visited by the bee. Without any bee visitation to flowers, southern blueberries set no fruit. It was estimated that the lifetime pollination efforts of one healthy O. ribifloris female contributed to the production of 12 to 24 dollars worth of fresh blueberries.
Technical Abstract: The behavioral traits and the pollination efficiency of Osmia ribifloris Cockerell (Hymenoptera: Megachilidae) were studied to assess the potential value of this bee for pollinating southern blueberry crops (Vaccinium sect. Cyanococcus). Emergence for this typically univoltine bee can be made to coincide with blueberry flowering, but there were some unusual patterns. For example, some bees delayed prepupal development and emerged one year late (i.e. parsivoltinism). Adults began foraging at blueberry flowers at air temperatures as cool as 9 deg. C. Thirty-three to 67 percent of open-pollinated rabbiteye blueberry (Vaccinium ashei Reade) flowers visited solely by female O. ribifloris set seeded fruits. Bagged flowers that excluded O. ribifloris resulted in 0-5 percent seedless fruit. Calculations based on flower visits and fruit set for female bees suggest that the monetary return a farmer receives from each female bee that nests in the orchard is about 12.00 to 24.00 dollars.