摘要
本文是毛白杨胚胎学研究的第二部份。研究了毛白杨胚珠、胚囊的构造,受精作用及胚的发育过程;找出了授粉前后花序的外部特征与胚珠发育情况之间的关系。 子房由二心皮合成。柱头四裂;花柱为开放型;基生胎座,上生2—4枚胚珠,通常1—2枚发育,其余败育。胚珠倒生型;珠柄发达;单珠被;厚珠心。直列式四分体;珠孔受精。双受精现象发生在授粉后40小时至6天之间。核型胚乳,胚的发育为简化的“十字花型”。 对珠被的特点,胶囊的发育类型,受精的方式以及胚的发育类型予以讨论。
This paper is the second part of Some embryoloical observations on Populus tomentosa Carr. the structure of ovule,development of embryo sac, fertilization and development process of embryo were studied. The relations between outside characteristics of catkin and development of ovule during pre-pollination and post-pollination were given.The ovary consists of two carpels. The stigma is 4-lobed. The style is open; placenta basal with 2 - 4 ovules;usualy only 1-2 ovules fertile. Ovule anatropous with funiculus well developed, unitegmic, crassinucellar-the megaspore tetrad linear, porogamy. Aater pollination the double fertil ization will be completed in 40 hours to 6 days. The endosperm is of 'nuclear type' . The embryogeny conforms to the simplified 'Crucifer type' .Integument characteristics, development type of embryo sac, the way of fertilization and embryogeny were discussed.
