稻麦胚乳游离核的分裂

用整体解剖法和树脂切片法观察了水稻、小麦和大麦胚乳游离核结构和分裂过程。结果表明，（１）胚乳游离核和胚乳细胞的分裂有２种形式：无丝分裂与有丝分裂，其中麦类以有丝分裂为主，水稻则以无丝分裂所占的比例很大；（２）核期结束时，游离核之间产生成膜体，由成膜体形成细胞壁；（３）胚乳核的分裂受多种因素影响，温度对胚乳核分裂影响最显著，气温高时分裂加快，核期缩短；（４）种间的胚乳核差异较大。通常细胞核小的种，核分裂的周期短。

DIVISION OF FREE NUCLEI OF RICE ANDWHEAT ENDOSPERM

Structure and division process of free nuclei of endosperm of rlce,wheat and barley were observed bythe method Of total dissection and resin-embedding sections,Main results were as follows:(1)In endosperln,the divi-sion of free nuclei and cells had two kinds of forms:amitosis and mitosis. In wheat and barlev endosperm,main formwas mitosis and in rice endosperm amitosis took a large proportion;(2)When nuclear phase ended,the phragmoplastwas formed among free nuclei,then the cell wall was developed;(3) Division of endosperm nuclei was affected by sev-eral factors.Temperature was the most important factor. When temperature rised,the rate of division increased,andnuclear phase shortened.(4) The difference of endosporm nuclei was relatively obvious among those of famllies, Gen-erally the smaller a nucleus was,the shorter the nuclear division phase was.