Article

Reproduction of Varroa destructor in South African honey bees: Does cell space influence Varroa male survivorship?

Department of Zoology and Entomology, University of Pretoria, Πρετόρια/Πόλη του Ακρωτηρίου, Gauteng, South Africa
Apidologie (Impact Factor: 1.68). 01/2002; 33(1). DOI: 10.1051/apido:2001007

ABSTRACT

The ability of Varroa destructor to reproduce in the African honey bee Apis mellifera scutellata was studied. In addition, the effects of space within the brood cell and short brood developmental time on mite reproduction, was investigated using A. m. scutellata cells parasitised by a A. m. capensis worker pseudo-clone. In A. m. scutellata worker cells Varroa produced 0.9 fertilised females per mother mite which is the same as found in susceptible European honey bees, but greater than the 0.4 produced in cells containing the pseudo-clone. Low mite reproductive success in cells containing pseudo-clone was mainly as a result of increased mite mortality. This was caused by male protonymphs and some mothers becoming trapped in the upper part of the cell due to the pseudo-clone being 8% larger than their host and not due to their short developmental time. Therefore, mite populations in South African A. m. scutellata and A. m. capensis honey bees are expected to increase to levels observed in Europe and USA.

Download full-text

Full-text

Available from: Per Kryger
  • Source
    • "By contrast to Brazil, only the Korean mite haplotype has been reported in this region (Anderson and Trueman 2000). When the mite was found in South Africa, mites reproduced as successfully in A. m. scutellata brood as they did in European races and it was suspected that apiculture in Africa would experience a similar negative impact from the presence of mites (Martin and Kryger 2002). Some colony losses were reported just after the mite was introduced, but the situation is now stable, which could suggest that an adaptive response by the host has occurred in response to mite infestation (Allsopp 2006). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The Varroa destructor mite is the largest threat to apiculture worldwide and has been responsible for devastating losses of wild honeybee populations in Europe and North America. However, Varroa mite-resistant populations of A. mellifera honeybees have been reported and documented around the world with a variety of explanations for their long-term survival with uncontrolled mite infestation. This review synthesizes the work on naturally occurring survival to Varroa mites and discusses what these honeybee populations can signify for apiculture.
    Full-text · Article · Dec 2015 · Apidologie
  • Source
    • "Such negative effects could result in significant selection among colonies exposed to the mites, especially in honeybee populations that are not being managed by beekeepers , e.g. the wild population in Africa (Dietemann et al. 2009; Pirk et al. 2014). In South Africa, the presence of Varroa mites was first recorded in savannah (Apis mellifera scutellata) and Cape (Apis mellifera capensis) honeybee colonies in the late 1990s (Allsopp, 1997, 2006; Martin and Kryger, 2002). It has been suggested that in both South African sub-species there has been selection among colonies for survival to mite infestation. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Varroa destructor is considered the most damaging parasite affecting honeybees (Apis mellifera L.). However, some honeybee populations such as the savannah honeybee (Apis mellifera scutellata) can survive mite infestation without treatment. It is unclear if survival is due to resistance mechanisms decreasing parasite reproduction or to tolerance mechanisms decreasing the detrimental effects of mites on the host. This study investigates both aspects by quantifying the reproductive output of V. destructor and its physiological costs at the individual host level. Costs measured were not consistently lower when compared with susceptible honeybee populations, indicating a lack of tolerance. In contrast, reproduction of V. destructor mites was distinctly lower than in susceptible populations. There was higher proportion of infertile individuals and the reproductive success of fertile mites was lower than measured to date, even in surviving populations. Our results suggest that survival of savannah honeybees is based on resistance rather than tolerance to this parasite. We identified traits that may be useful for breeding programmes aimed at increasing the survival of susceptible populations. African honeybees may have benefited from a lack of human interference, allowing natural selection to shape a population of honeybees that is more resistant to Varroa mite infestation.
    Full-text · Article · Dec 2015 · Parasitology
  • Source
    • "It has been suggested (e.g., Medina and Martin 1999) that smaller cells may cause higher mortality of immature mites, because the mites develop directly beside immature bees in cells (Donzé and Guerin 1997) so a smaller space between the developing bee and the cell wall might hamper the movements of the immature mites, reducing their ability to feed and thereby raising their mortality. One study that has provided support for the concept of small-cell combs for Varroa mite control was conducted in South Africa with African honeybees (Martin and Kryger 2002). Colonies were established in which larger bees (Apis mellifera capensis, similar in size to European bees) and smaller bees (A. m. scutellata , smaller than European bees) were reared together in small-cell (4.6 mm) combs, and it was found that both mother mite mortality and male offspring mite mortality were higher in the cells with larger bees. "
    [Show abstract] [Hide abstract]
    ABSTRACT: We tested the idea that Varroa destructor can be controlled in colonies of the European subspecies of Apis mellifera by providing them with combs built of small cells, in which immature mites might have difficulty developing for lack of space. We established seven pairs of equal-size colonies that started out equally infested with mites. In each pair, one hive contained only standard-cell (5.4mm) comb, and the other contained only small-cell (4.8mm) comb. We measured the colonies' mite loads at monthly intervals across a summer. No differences arose between the two treatment groups in their mean mite loads (mites per 100 worker bees or mite drop per 48h). We suggest that providing small-cell combs did not inhibit mite reproduction because the fill factor (thorax width/cell width) was only slightly higher in the small cells than in the standard cells (79% and 73%, respectively). Keywords Apis mellifera – Varroa destructor –small cell–mite control–cell size
    Full-text · Article · Aug 2011 · Apidologie
Show more