Submitted to: Journal of Kansas Entomological Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 19, 1996
Publication Date: N/A
Interpretive Summary: The North Central Regional Plant Introduction Station located at Ames, IA, has for years relied on honey bees as early spring pollinators of Brassica in field cages. In order to have enough honey bees available we must purchase them from "companies located" in southern states. This increases the risk of importing mites and it increases our costs. In 1977, Osmia cornifrons, a mason bee native to Japan, was imported into the United States for use as an orchard pollinator. Because these bees are effective early, cool season pollinators, we decided to use them to pollinate Brassica in field cages. However, for these bees to be useful pollinators, we must know how to manage them. This paper reports on testing 4 environments for storing O. cornifrons during the winter: (1) outdoors, (2) in an unheated machine storage shed, (3) in a 4-5 deg C seed storage room, and (4) in a 1-2 deg C growth chamber. Overall, the 1-2 deg C storage conditions resulted in the highest emergence of bees for early spring pollination of Brassica.
Technical Abstract: In 1977, Osmia cornifrons (Radoszkowski) was introduced from Japan into the United States as an orchard pollinator. The bee is of interest to the North Central Regional Plant Introduction Station because it is a highly efficient, cool season pollinator. We have need for early spring pollinators to possibly replace honey bees (Apis mellifera Linnaeus) for pollination of Brassica spp. in field cages. O. cornifrons overwinter as diapaused adults. We tested four overwintering storage treatments (outdoors, in an unheated machine shed, in a 4-5 degree C seed storage room, and in a 1-2 degree C growth chamber) to determine the optimal winter storage conditions for this insect. Overall storage in the 1-2 degree C growth chamber resulted in the highest emergence of bees for three test dates (April, June, and August).