中国蓝果树的胚胎学研究

中国科学院大学学报

中国蓝果树的胚胎学研究

陈令静, 钱南芬, 王伏雄

收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:1991-11-10 发布日期:1991-11-10
通讯作者: 陈令静

The Embryology of Nyssa sinensis Oliv. (Nyssaceae)

Chen Ling-Jing, Qian Nan-Fen, Wang Fu-Hsiung

Received:1900-01-01 Revised:1900-01-01 Online:1991-11-10 Published:1991-11-10
Contact: Chen Ling-Jing

摘要/Abstract

摘要：

中国蓝果树的花芽当年形成。小孢子母细胞减数分裂为同时型。孢子四分体多为四面体形。花药绒毡层分泌型，细胞具多倍体核。子房常1室，少2室。花柱实心，具引导组织。引导组织在子房室顶端形成珠孔塞。胚珠倒生，悬垂，具单珠被。假厚珠心。珠被维管束延伸进入珠被。孢原细胞1 个，位于珠心表皮细胞之下。孢原细胞直接扩大形成大孢子母细胞。珠心冠大多不存在。蓼型或葱型胚囊。近合点端的无功能大孢子最先压扁退化。珠孔受精。精卵核融合为有丝分裂前型。极核在受精时融合。反足细胞短命。细胞型胚乳。成熟胚与种子近等长，种子叶基部多少心形。子具胚乳。胚和胚乳均不具喜树碱。

同美洲产的蓝果树相比较后，本文总结了蓝果树属较稳定的有分类学意义的胚胎学特征。

关键词: 中国蓝果树, 胚胎学

Abstract:

The flower develops in March and blossoms in early May in Nanjing. The

cytokinesis of microsporocytes is simultaneous and most tetrads are tetrahedral. The tapetum

is secretory and the nuclei become polyploid at last. The style is solid and most ovaries are

unilocular, rarely bilocular. The ovule is pendulous, anatropous and unitegmic. The nucellus is

pseudocrassinucellate. An obturator formed by transmitting tissue covers the micropyle. The

raphe vascular strand extends into the integument when it reaches the chalaza and on a whole

keeps a “U” shape. The endothelium cell is uninucleate. In most cases no nucellar cap is

formed. No hypostase is found below the embryo sac. The archesporium is one-celled. The

embryo sac development conforms to the Polygonum or Allium types. The degeneration of

the megaspores in the linear tetrad usually occurs from the chalazal toward the micropylar

end. Two synergids persist during fertilization. Three antipodal cells are uninucleate and

ephemeral. Two polar nuclei fuse at the time of fertilization. The fertilization type accords

with porogamy. The syngamy is premitotic. The development of endosperm is cellular.

The initial four successive divisions of the primary endosperm cell are transverse-vertical-

transverse-transverse subsequently, giving rise to sixteen cells of the early endosperm. The

mature embryo is straight and nearly as long as the endospermous seed. The cotyledons are

more or less cordate at base. The seedoat is thin and composed of 5-11 layers of compressed

cells. Neither embryo nor endosperm contain the alkaloid camptothecine.

The major similarities of Nyssa sinensis to the American nyssas in embryology, which

may be a counted as the generic features, are the polyploid tapetum cells, the unitegmic ovule

with U-shaped vascular strand, the direct enlargement of the archesporial cell to produce the

megasporocyte, the pseudocrassinucellus, the usual absence of the nucellar cap, the

Polygonum or Allium type of the embryo sac development, the first degeneration of the

metachalazal megaspore, the ephemeral antipodal cells, a single nucleolus in the nucleus of

the primary endosperm cell, the more or less cordate base of the cotyledons.

Key words: Nyssa sinensis div., embryology

陈令静, 钱南芬, 王伏雄. 中国蓝果树的胚胎学研究[J]. 中国科学院大学学报.

Chen Ling-Jing, Qian Nan-Fen, Wang Fu-Hsiung. The Embryology of Nyssa sinensis Oliv. (Nyssaceae)[J]. .

[1]	薛春迎,何廷农,刘建全. 四数獐牙菜的胚胎学及其系统学意义[J]. 中国科学院大学学报, 1999, 37(3): 259-263.
[2]	任毅,王玛丽,胡正海. 独叶草属的胚胎学及其系统学意义[J]. 中国科学院大学学报, 1998, 36(5): 423-427.
[3]	张芝玉, 路安民, 潘开玉, 温洁. 杜仲科的解剖学和胚胎学及其系统关系[J]. 中国科学院大学学报, 1990, 28(6): 430-441.
[4]	张芝玉. 猕猴桃科的花粉形态及其系统位置的探讨[J]. 中国科学院大学学报, 1987, 25(1): 9-23.