Embryogeny in Haemmanthus Albiflos Jacquin

Abstract

There has been concern over the controversial position of the genus Allium in the classification scheme. Allium has been put into the Liliaceae because of its superior ovary and into the Amaryllidaceae because of umbels subtended by membranaceous bracts. The first purpose of this investigation is to study the embryogenesis and subsequent embryogeny of Haemanthus to evaluate affinities between Allium and Haemanthus. Since Allium has stalked cotyledons, it was thought that we could appeal to Haemanthus embryogenesis for evidence as to its relationships, since it is a genus which has been considered both primitive with the Amaryllidaceae and related to Allium. If Haemanthus is shown to have stalked cotyledons, this would tend to support the position that Allium may be closely related to the Amaryllidaceae. If not, this would tend to discourage adoption of the hypothesis that Allium is related to the Amaryllidaceae. Another phenomenon recognized in Haemanthus is the difficulty of obtaining high percentage of fruit-set. In an inflorescence of about 100 flowers only about 10 fruits are produced. Each fruit contains one or two seeds and very rarely three seeds. The second purpose is to study (1) pollen grain viability; (2) developmental stages in micro and megasporogenesis; and (3) the effects of hand-pollination on fruit-set