Factors affecting duration of the postcapping period in brood of the honey bee (Apis mellifera carnica)
Reducing the duration of the length of the capped brood phase is considered to be a good approach for breeding honey bees resistant to Varroa jacobsoni. In cross-fostering experiments using six colonies of Apis mellifera carnica, in addition to the genotype of worker brood, the nursing colony also affected the duration of the postcapping stage. Regression analysis of postcapping duration on precapping duration showed that the relationship was negative and highly significant (b = -0.05, P < 0.001), so that a shorter postcapping stage was partly compensated for by a longer precapping period. The ratio between postcapping and precapping periods was significantly affected by genotype of worker brood (P < 0.001), by effects of the precapping nurse colony (P = 0.008) and by effects of the postcapping nurse colony (P < 0.001). The duration of the precapping and postcapping stages and the inverse relationship between them was shown to have a genetic basis. The results show that the nurse colony has an important impact on the duration of the postcapping stage and this should be considered in selection programmes.