02217nas a2200217 4500000000100000000000100001008004100002260007000043653001800113653002100131653002200152653001500174653002400189653003000213100001400243700001300257245016400270490000800434520154300442022001401985 2018 d c11/2018bSchlütersche Verlagsgesellschaft mbH & Co. KGaHannover10aColony losses10alocal adaptation10aVarroa destructor10aNosema spp10adeformed wing virus10aacute bee paralysis virus1 aM Meixner1 aA Uzunov00aGenotype-environment-interactions and the occurrence of honey bee diseases affect the survival of honey bee colonies – summary from a pan-European experiment0 v1313 aTo explore genotype-environment-interactions in honey bees, the survival and performance of 597 colonies, representing five subspecies and 16 different genotypes, were comparatively studied in the framework of the COLOSS project. The study was carried out from 2009 to 2012 in 21 apiaries across Europe. The colonies were continuously assessed for traits of apicultural interest and closely monitored for pests and pathogens. During the experiment, chemical treatments against any disease were not permitted. Infestation with the parasitic mite Varroa destructor was the main reason for losses, followed by queen problems and infection with the gut parasite Nosema spp. On average, colonies with queens from local origin survived significantly longer compared to non-local origins (83±23 days; p lt;0.001). The occurrence of all diseases (Varroa, Nosema, viruses) was strongly affected by environmental factors (apiary effects). An in-depth analysis was carried out in one apiary as a case study; here, it was observed that pathogen levels were significantly lower in local colonies compared to non-local ones. Over all, the results of the experiment demonstrate strong genotype-environment-interactions and show that locally adapted populations perform better and survive longer than foreign genotypes. To preserve such populations, the support of local breeding activities needs to be prioritised in order to optimise sustainable productivity and to increase their acceptance through beekeepers, and to prevent colony losses. a0005-9366