Juvenile hormone titer and reproduction of Varroa jacobsoni in capped brood stages of Apis cerana indica in comparison to Apis mellifera ligusticaP. Rosenkranza, N.C. Tewarsonb, A. Rachinskya, A. Strambic, C. Strambic and W. Engelsa
a LS Entwicklungsphysiologie, Zoologisches Institut der Universität, Auf der Morgenstelle 28, D-72076 Tübingen, Germany
b Department of Zoology, Ewing Christian College, Allahabad-211003, India
c Laboratoire de Neurobiologie, CNHS, BP 71, F-13402 Marseille Cedex 9, France
Abstract - The juvenile hormone (JH) III hemolymph titer of late larval and early pupal stages as determined by radioimmunoassay (RIA) does not differ significantly in Apis cerana and Apis mellifera, particularly in freshly-sealed worker brood. In drone brood, slightly higher JH III hemolymph concentrations were recorded. These results do not agree with the hypothesis that reproduction of the parasitic bee mite Varroa jacobsoni is regulated by host-derived JH. After checking over a thousand capped brood cells containing pupae, it was confirmed that in Apis cerana colonies fertility of female mites is restricted to drone hosts.
Key words: Apis cerana indica / Apis mellifera ligustica / juvenile hormone titer / reproduction / Varroa jacobsoni