Intra-ovarian trichomes in Bequaertiodendron magalismontanum: location, origin, structure and possible function in the reproductive process

Bifurcate, unicellular epidermal trichomes are characteristic of the Sapotaceae, but have only been reported on external surfaces of aerial plant organs. In Bequaertiodendron magalismontanum (Sond.) Heine & J.H. Hemsl. such trichomes were found inside the pistils of mature female and morphologically hermaphroditic flowers and inside young fruits. It is suggested that the intra-ovarian trichomes serve as bridges between stylar and ovarian transmitting tissue to facilitate the passing of highly selected pollen tubes across the interlocular compital space. In origin, structure and proposed function these thick-walled, intra-ovarian trichomes conform to characteristics typically assigned to obturators. Twee-armige, eensellige epidermale trigome is karakteristiek van die Sapotaceae, maar is nog net gevind op uitwendige oppervlakke van bogrondse plantdele. In Bequaertiodendron magalismontanum (Sond.) Heine & J.H. Hemsl. kom soortgelyke trigome ook binne die stampers van volwasse vroulike en morfologies hermafroditiese blomme en in jong vrugte voor. Daar word voorgestel dat die interne trigome as brûe tussen die styl- en vrugbeginseltransmissieweefsel dien, om sodoende goedgeselekteerde stuifmeelbuise in staat te stel om die interlokulêre ruimte van die kompitum te oorbrug. In oorsprong, bou en voorgestelde funksie stem hierdie dikwandige, interne vrugbeginseltrigomeo oreen met kenmerke wat vir obturators tiperend is.