Effects of genotype and environmental factors on the survival of European honeybee colonies
Résumé
To better understand the role of bee genetics in the Europe-wide occurrence of colony losses an experiment on genotype – environment interactions (GEI) was started by Coloss working group 4 in July 2009. 621 honeybee colonies, representing 18 different genotypes, were comparatively tested in 16 apiaries across Europe. The colonies were kept without any chemical treatments against Varroa destructor and other diseases. Colony and queen survival were registered continuously, besides bee population development, productivity, feed balance, swarming, gentleness, hygienic behaviour and the infestation with Varroa, Nosema and viruses. The tested genotypes clearly differed in their honey productivity, gentleness and swarming tendency which can at least partially be explained as a consequence of different breeding intensity for these traditional selection characters. However, it is important to note that even for these traits highly significant genotype – environment interactions were observed. To sum up our primary results, we can state a high relevance of interactions between honeybee genotypes and different environmental conditions within Europe. Obviously, the genetic adaption of honeybees to a specific environment influences its population dynamics, health status, and productivity. Consequently, the conservation of European honeybee diversity and the support of local breeding activities should be encouraged.