Genetic structure and distinctness of Apis mellifera L. populations from the Canary Islands

The genetic structure of Apis mellifera populations from the Canary Islands has been assessed by mitochondrial (restriction fragment length polymorphi sms of the intergenic transfer RNA(leu)-COII region) and nuclear (microsate llites) studies. These populations show a low level of genetic variation in terms of average number of alleles and degree of heterozygosity. Significa nt differences in the distribution of alleles were found in both data sets, confirming the genetic differentiation among some of the islands but not w ithin them. Two mitochondrial haplotypes characteristic of the Canary Islan ds are found at high frequencies, although populations are introgressed by imported honeybees of eastern European C lineage. This introgression is rat her high on Tenerife and El Hierro and low on Gran Canaria and La Gomera, w hereas on La Palma it has not been recorded. The finding of microsatellite alleles characteristic of the eastern European lineage corroborates the gen etic introgression. Phylogenetic analyses indicate that the Canarian honeyb ees are differentiated from other lineages and provide genetic evidence of their African origin.