ARS | Publication request: Patriline variation of Nosema ceranae levels in Russian and Italian honey bees

Submitted to: Cold Spring Harbor Meeting
Publication Type: Abstract Only
Publication Acceptance Date: April 8, 2011
Publication Date: May 8, 2011
Citation: Bourgeois, A.L., Rinderer, T.E., Sylvester, H.A., Holloway, B.A. 2011. Patriline variation of Nosema ceranae levels in Russian and Italian honey bees. Cold Spring Harbor Meeting. 17.

Technical Abstract: The microsporidian Nosema ceranae has invaded managed honey bee colonies throughout the world. While the presence of N. ceranae is common, infection levels are highly variable, even among bees within a single colony. The underlying mechanisms driving this variation are not well-understood. The high degree of individual variation within a colony suggests some degree of genetic resistance to N. ceranae infections may exist among managed honey bee colonies. One likely source for this variation stems from the polygamous nature of honey bee queens, producing multiple patrilines within each colony. We investigated the relationship between infection levels of N. ceranae and patriline membership by sampling individual bees from colonies from both Russian and Italian stocks. A total of 720 bees were collected from 5 Russian and 5 Italian colonies. Individual bees were tested for N. ceranae infection levels using qPCR, and were genotyped to determine patriline membership. Levels of N. ceranae varied significantly at the stock level (Russian: 3.68 x 106 ± 1.88 x 106 nosema/bee and Italian: 9.14 x 106 ± 4.62 x 106 nosema/bee; P = 0.008) and at the colony level for both Russian (P = 0.002) and Italian (P = 0.003) bees. Patriline-based variance was evident among only the Russian bees (P = 0.024). There was substantial variation in N. ceranae levels among Italian bees, ranging from 0 to 2.12 x 109 nosema/bee, however this variation was not associated with patriline membership (P = 0.742). The variance in N. ceranae infection among Russian honey bee patrilines demonstrates a genetic basis for resistance to N. ceranae infection which conforms to predictions of models that relate patriline variance and abundance to disease resistance in honey bees. This difference between Russian and Italian honey bees may derive from Italian honey bees having only a short history of exposure to N. ceranae while Russian honey bees may have had 150 years of exposure.