Vertical zonality of the gynoecium in Sansevieria Thunb. and Dracaena Vand. ex L. species (Asparagaceae)

Abstract

Oksana Fishchuk, Anastasiya Odintsova

In ten Sansevieria and two Dracaena species the vertical zonality of the gynoecium after W. Leinfellner (1950), as well as the structure of the septal nectary after the concept of its vertical zonality were studied. It was revealed four vertical zones in the gynoecium of S. hyacinthoides, S. spicata, S. aetheopica, S. grandis, S. suffruticosa, D. fragrans and D. surculosa (synascidiate, hemisynascidiate, hemisymplicate and asymplicate) while in the gynoecium of S. grandicuspis, S. fernwood, S. parva, S.trifasciata and S. doonerу hemisymplicate zone is absent. Septal nectary in the studied Sansevieria species (except S. suffruticosa) and in D. fragrans is devided into the zones of distinct, common and external nectary (nectary split), while in D. surculosa and S. suffruticosa the zone of distinct nectary is absent. In all studied species septal nectary height is more than the locules height, moreower the most height of the septal nectary is in the species with the greatest height of the ovary (S. hyacinthoides and S. grandis). In the studied species five types of the vertical zonality of the ovary and septal nectary were detected. In Dracaena species septal nectary has relatively smallest height.