A study of histogenesis of integuments in Euphorbiaceae using phase contrast, and an pplicatin of its utility to embryology.

利用相位对比和Nomarski干涉光学技术，重新研究了被子植物中罕见的大戟科被珠的组织起源，并对这些新方法在观察茜草科和乌兰科胚胎学特征中的应用进行了探讨。根据对南方菖蒲（Acalypha australis）、大戟（Euphorbia helioscopia）、棘叶菖蒲（E. supina）和尿叶菖蒲（Phyllanthus urinaria）的观察，发现其内被属真皮起源，而不是先前报道的真皮下起源（Bor & Bouman, 1974; Bor & Kapil, 1976）。诺玛斯基干涉光学清晰地区分了发育被的细胞衍生物。结果表明，大戟科植物被毛的组织发生模式与其他被子植物不再存在差异。本文首次对geltidaceae - ulmacae（15（-18）属）的花粉细胞数量进行了广泛的观察。双细胞花粉存在于石竹科（Aphananthe aspera）、石竹科（Chaetacme aristate）、石竹科（Holo-ptelea integrgrifolia）和石竹科（Hemiptelea davidii）；水生Planera aquatica和泽尔科Zelkova serrata（榆科）的2细胞和3细胞花粉；榆属植物的3细胞花粉。结果表明，从2细胞到3细胞花粉的进化变化发生在榆科的几个属的有限类群中，而在草苔科没有发生。通过对小黄芽胚珠的观察，发现Nomarski干涉光学很容易表现出一些胚胎学特征，如咬痕、抱核状态等。

Using phase contrast and Nomarski interference optics, the histogenetic origin of integuments in Euphorbiaceae that has been reported to be unusual in angiosperms in reinvestigated, and the utility of those new approaches is examined in observing embryological features of Celtidaceae and Ulamceae.1. The inner integument of Euhorbiaceae, based on observations in Acalypha australis, Euphorbia helioscopia, E. supina, and Phyllanthus urinaria, is found to be of dermal origin, rather than is it of subdermal origin as reported earlier (Bor & Bouman, 1974; Bor & Kapil, 1976). Nomarski interference optics clearly distinguish cell derivatives in developing integuments. This result concludes that there is no longer a gap in histogenetic pattern of integument between Euphorbiaceae and other angiosperms.2. An extensive observation on pollen cell number in Geltidaceae-Ulmaceae (comprising 15(-18) genera) is made for the first time. Two-celled pollen is found to occur in Aphananthe aspera, Chaetacme aristate (Celtidaceae), Holo-ptelea integrifolia and Hemiptelea davidii (Ulmaceae); both 2- and 3-celled pollen in Planera aquatica and Zelkova serrata (Ulmaceae); 3-celled pollen in Ulmus davidiana. The results suggest that an evolutionary change from 2- to 3- celled pollen has occurred in a restricted group of several genera in Ulmaceae but not in Celtidaceae.3. Based on observation of young ovules of Aphananthe aspera, it is found that Nomarski interference optics easily demonstrate some embryological features such as the bitemy, crassinucellate condition, etc.