作 者 :Chen Zu-Keng, Wang Fu-Hsiung, Li Zhi-Li
期 刊 :植物分类学报 1990年 3期
关键词:知母胚胎发生花粉胚囊胚乳;
Keywords:Anemarrhena asphodeloides, embryogenesis, embryo sac, endosperm, Pollen,
Abstract:
Anemarrhena asphodeloides Bunge is the only species of Anemarrhena in Li-
liaceae, which possesses three stamens. The flowers in this species have following features:
(1) Crystalliferous cells are present in the perianth and the filament. (2) Epidermal cells of
filaments and the inner perianth appears verruciform. (3) In longitudinal section, a number
of the multicellular hairs were found in the apex of the inner perianth. The above characteris-
tics of Anemarrhena are possibly important and differ from those of the other genera in
Liliaceae.
The main aim of the present paper is to deal with the female gametophyte and embryo-
genesis in Anemarrhena. The development of embryo sac is similar to that of Ornithogalum
(Tilton et al., 1981), belonging to the Polygonum type, but there is a short embryo sac hausto-
rium at the antipodal end. Before fertilization the two polar muclei fuse into a secondary nu-
cleus. The filiform apparatus was found in the synergid.
The early development of proembryo in Anemarrhena is similar to that of Najas (Hu,
1982). After fertilization the zygote has a short stage of dormancy. When the endosperm
has 12-16 free nuclei, the first division of the zygote takes place, forming an apical cell and
a basal cell. Then the apical cell undergoes transversal divisions 2 or 3 times, forming a line
of three to four cells. The basal cell usually does not further divide.
The endosperm formation in Anemarrhena is the Helobial type. The small chalazal cham-
ber is usually ephemeral and 2-4-nucleate, while the large micropylar one may be a multi-
nucleate before wall formation.