Ovule orientation, curvature and internal structure in the Aloaceae

Abstract

This scanning electron and light microscope study, conducted on mature ovules of arbitrarily chosen species of the genera Aloe L., Astroloba Uitew., Chortolirion A.Berger, Gasteria Duval, Haworthia Duval and Poelinitzia Uitew., indicated that the Aloaceae are exclusively hemitropous. This report is, seemingly, the first account of a consistently hemitropous monocotyledonous family. At generic rank, additional unifying embryological characters were found in the orientation of the ovules, the organisation of the integuments, the position of the remaining nucellar tissue and the structure and arrangement of the embryo sac elements.