Author
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Kemp, William - Bill |
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BOSCH, JORDI - UAB,BELLATERRA,SP |
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Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/1/2005 Publication Date: 12/8/2005 Citation: Kemp, W.P., Bosch, J. 2005. Effect of temperature on Osmia lignaria (hymenoptera:megachilidae) prepupa-adult development, survival, and emergence. Journal of Economic Entomology. 98(6):1917-1923. Interpretive Summary: Interpretive summary: The American Beekeeping Federation estimated that during 2005 about 50 percent of the honey bee colonies used for pollination in California almonds were either killed or severely weakened from varroa mite infestations. Press reports suggest that the chemical treatments that beekeepers rely on to combat varroa mites are being rendered ineffective due to the continued development of resistance in the mites. The solution to this pollinator crisis will likely come from two areas: 1) further research on honey bee genetics and novel pest management options, and 2) developing new bees for pollination to diversify our Nation’s pollinator portfolio. The blue orchard bee, Osmia lignaria, is being developed as a manageable orchard pollinator throughout North America. Adults of this species are active in the spring, building and provisioning nests with brood, and provide outstanding pollination for early flowering tree fruit crops including almonds, apples, sweet cherries, plums, and pears. In this article, we report on the second of two experiments on the development, mortality, and emergence of O. lignaria at selected laboratory temperature regimes and outdoors that we conducted during 1997-1998. In the first experiment (published previously), we compared temperature treatments for their adequacy in maintaining healthy O. lignaria populations. In a second experiment (reported here), we determined the relationship between rearing temperatures and prepupa-adult development rates, as well as emergence time and longevity after wintering and incubation the following spring. We observed important differences in O. lignaria prepupa versus pupa responses to selected temperature treatments. The implications of these results to the ultimate development of regionally adapted pollinator populations are discussed. Technical Abstract: Technical abstract: The solitary bee Osmia lignaria Say is being developed as an orchard pollinator in throughout North America. Female bees are active during the early spring and construct nests consisting of a linear series of unlined cells delimited by mud partitions. Cells are provisioned with a pollen/nectar mass on which an egg is deposited, and nests are sealed with a mud plug. In 1997, we initiated two experiments on the development, mortality, and emergence of O. lignaria at selected laboratory temperature regimes and outdoors. In the first experiment (published previously), we compared temperature treatments for their adequacy in maintaining healthy O. lignaria populations. In a second experiment (reported here), we determined the relationship between rearing temperatures and prepupa-adult development rates, as well as emergence time and longevity after wintering and incubation the following spring. We observed important differences in O. lignaria prepupa versus pupa responses to selected temperature treatments. The relationship between temperature and days to pupa was U-shaped, with additional time to transit the prepupa-pupa interval at temperatures above and below 26ºC. The negative relationship between temperature and the length of the pupa to adult interval contrasts with the U-shaped thermal response observed for prepupae. Thus, with each increase in thermal heat units over the range of temperature treatments tested, we observed an additional reduction in the pupa-adult interval. Individuals reared at constant 18ºC required 2.4 times as many days to transit the pupa-adult interval compared with those at constant 32ºC. The implications of these results to the ultimate development of regionally adapted pollinator populations are discussed. |
