Varroa destructor mite causes mortality of Apis mellifera bees throughout the world. Its greatest damage to these colonies has been reported in European countries and North America. The impact of the mite is related to the climate and the bee race on each region in which the plague has been established. Varroa causes little damage to the colonies of africanized honeybees in Brazil and the levels of infestation are relatively small and stable. The reproductive ability of Varroa females was evaluated in pupae of workers of 17-18 days of age, obtained from eight beehives of africanized bees for twelve months. The average number of offspring (deutonymphs, protonymphs and eggs) each Varroa produced was 3.18 ± 0.19. The average total number of deutonymph and protonymph was, respectively, 1.57 ± 0.15 and 1.61 ± 0.14. The levels of infestation demonstrated that the plague continue reaching low levels, the average was 4.11 ± 3.42.

Reproductive ability and level of infestation of the Varroa destructor mite in Apis mellifera apiaries in Blumenau, State of Santa Catarina, Brazil

SummaryThe effective reproductive capacity of Varroa destructor in honey bee colonies is currently calculated on the basis of the number of female deutonymphs found in singly infested worker brood cells at 17–18 days (two to three days before the bee emerges). This calculation presumes that the deutonymphs will reach the adult stage by the time that the adult bee ecloses. Some deutonymphs may not, however, reach the adult phase and there also could be mortality. In order to examine this possibility, we studied mite reproduction in worker brood of Africanized honey bee colonies at 17–18 days and then selected eight colonies in which over 90% of the infested brood cells contained a single original female mite. The mean proportion of singly infested worker brood cells in these colonies was 96.3%. Consequently, by subtracting one from the total number of adult female mites found at the time the bee emerged we would be able to estimate the effective reproductive capacity of the original mites, with little erro...

Diego Fagundes Kolling

Papers

A new approach for detecting effective reproductive ability of Varroa destructor (Acari: Varroidae)