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International audienceWe investigated the relationship between infestation levels of Nosema ceranae and patriline membership by sampling individual worker bees from five colonies from both Russian and Italian lineages. Individual workers were tested for N. ceranae infestation level using qPCR, and then genotyped to determine their patriline membership. Levels of N. ceranae infestation differed significantly between lineages and colonies for both Russian and Italian workers. Patriline-based variance was evident only among the Russian workers. There was substantial variation in N. ceranae levels among Italian workers, ranging from 0 to 2 × 109 Nosema/bee, but this variation was unrelated to patriline membership. The results for Russian honey bees are congruent with predictions derived from the parasite hypothesis for the evolution of polyandry-patrilinial variance in parasite tolerance contributes to colony level resistance by reducing the probability of catastrophic failure that might occur if a colony was genetically homogeneous

SUMMARYIn the Americas, almost all colonies of Africanized and European honey bees that are building their own comb can be identified in the field, by measuring the distance spanned by 10 worker cells. Discriminant analysis of worker bee morphometric characteristics can be used to identify bees which are not producing their own comb. The simplest analysis uses measurements of fore-wing length and correctly identified 86 % (P > 0.90) of 86 Africanized and 50 European colonies, with no misidentifications. A multivariate analysis of fore-wing length, partial hind-wing length, femur length and « clean weight », correctly identified 91 % (P > 0.90) of these samples, with no misidentifications. The formulae, constants and procedures for these analyses arc provided.

A genetic stock certification assay was developed to distinguish Russian honey bees from other European (Apis mellifera L.) stocks that are commercially produced in the United States. In total, 11 microsatellite and five single-nucleotide polymorphism loci were used. Loci were selected for relatively high levels of homogeneity within each group and for differences in allele frequencies between groups. A baseline sample consisted of the 18 lines of Russian honey bees released to the Russian Bee Breeders Association and bees from 34 queen breeders representing commercially produced European honey bee stocks. Suitability tests of the baseline sample pool showed high levels of accuracy. The probability of correct assignment was 94.2% for non-Russian bees and 93.3% for Russian bees. A neighbor-joining phenogram representing genetic distance data showed clear distinction of Russian and non-Russian honey bee stocks. Furthermore, a test of appropriate sample size showed a sample of eight bees per colony maximizes accuracy and consistency of the results. An additional 34 samples were tested as blind samples (origin unknown to those collecting data) to determine accuracy of individual assignment tests. Only one of these samples was incorrectly assigned. The 18 current breeding lines were represented among the 2009 blind sampling, demonstrating temporal stability of the genetic stock identification assay. The certification assay will be used through services provided by a service laboratory, by the Russian Bee Breeders Association to genetically certify their stock. The genetic certification will be used in conjunction with continued selection for favorable traits, such as honey production and varroa and tracheal mite resistance.