|De Guzman, Lilia|
|Phokasem, Patcharin - Chiang Mai University|
|Khongphinitbunjong, Kitiphong - Mae Fah Luan University|
|Chantawannakul, Panuwan - Chiang Mai University|
Submitted to: Journal of Invertebrate Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/12/2018
Publication Date: 2/22/2018
Citation: De Guzman, L.I., Phokasem, P., Khongphinitbunjong, K., Frake, A.M., Chantawannakul, P. 2018. Successful reproduction of unmated Tropilaelaps mercedesae and its implication on mite population growth in Apis mellifera colonies. Journal of Invertebrate Pathology. 153:35-37.
Interpretive Summary: Tropilaelaps mites are serious parasites of European honey bee colonies and are known to have a competitive advantage over varroa mites in Asia. However, factors that contribute to their persistence are not well understood. In this study, we demonstrated that reproduction of tropilaelaps mites was disrupted when infested brood cells are disturbed or manipulated due to hygienic behavior. Although brood removal or recapping of infested brood cells lower the mites’ reproductive potential, their lack of phoretic period will overcome such reproductive deficit. Likewise, the potential ability of virgin daughters of tropilaelaps mites to produce both males and females significantly improves their chances of growth over varroa mites. These observations may help explain why tropilaelaps mites are the most predominant and successful parasitic mites of A. mellifera in Thailand.
Technical Abstract: Highly hygienic colonies are known to reduce the reproductive potential of Varroa destructor. For Tropilaelaps mercedesae, information on how bee behavior may influence the mite’s reproductive potential is currently unknown. In this study, we assessed the influence of recapping on the reproduction of infesting T. mercedesae and brood removal on re-invading mites in Apis mellifera colonies. In recapped cells, the total number of progeny and the number of matured daughters or sons were lower than in brood cells with normal wax cappings. In contrast, higher proportions of foundress mites that produced nymphs only or did not produce any progeny were observed in recapped cells. We also inoculated mites collected from newly sealed larvae (NSL) and tan-bodied pupae (TB) into NSL. A majority of the progeny produced by NSL mites reached adulthood; ~1/3 produced a mature son and daughter and ~½ produced mature daughters only. Although most of the TB mites reproduced, a majority produced either mature son with nymphs (33%) or nymphs only (32%). A high production (~60%) of mature daughters only was also recorded in naturally infested brood. About 84% of the inoculated foundresses that had or had not laid previously, and 78% of the new daughters that had no egg-laying experience reproduced suggesting that tropilaelaps mites can lay eggs without going through a phoretic phase. Likewise, of the eight “presumably unmated” daughters, four produced both mature sons and daughters, and four produced mature daughters only. This ability of virgin females to lay males and females, and to reproduce without spending a phoretic period on adult bees may play major roles in tropilaelaps mites’ competitive advantage over varroa mites.