西卡柱花草受精作用和胚及胚乳发育的研究

应用常规石蜡切片与压片方法，用铁矾苏木精、汞溴酚蓝和PAS反应等进行染色观察西卡柱花草（Stylosanthes scabra cv.seca）受精作用和胚及胚乳发育过程。开花后3－6h，发生双受精作用。卵核的受粗作用属有丝分裂前配子融合类型。核核受精过程有2种类型：（1）两极核融合成次生核，然后次生核与精核融合；（2）精核先也上极核融合，受精极核与另一极核直到有丝分裂开始时才融合。花后22－23h，合子分裂为二细胞原胚，经历单列细胞胚、长棒形胚、球形胚、心形胚、鱼雷表胚、幼胚、扩大生长胚阶段，花后25－30d胚发育成熟。胚发育属于茄型。在扩大生长胚时期胚体开始积累淀粉和蛋白质，花后8－9h初生胚乳核分裂，胚乳发育为核型。至胚长大，充满整个胚囊时胚乳开始退化，胚发育成熟时胚乳仅余残迹。

Fertilization and Development of Embryo and Endosperm in Stylosanthes scabra cv. Seca

The fertilization and embryo development of S.scabra were studied by means of squash and paraffin sectioning stained with iron hematoxylin, mercury-bromophenol blue and PAS. The double fertilization proceeded normally 3-6 h after anthesis. The fertilization of the egg nucleus with the sperm and polar nuclei with another sperm took place almost at the same time. The fertilization of the egg belonged to the premitotic type of syngame. The polar nuclei exhibited a similar fertilization procedure as the egg. Two types of fertilization for the polar nuclei with the sperm were observed: (1) The two polar nuclei were fused to form a secondary nucleus and then fused with the sperm; and (2) The sperm was fused with the upper polar nucleus to form a fertile polar nucleus, which would not be fused with the lower polar nucleus until the mitosis took place. After 22-23 h of anthesis the zygote started its first division to form a two-celled proembryo and experienced a series of development stages such as single-row celled, bat-like, globular, heart, tor- pedo, juvenile and spreading-growth stages. The embryo matured 25-30 d after anthesis. The development of the embryo was of the solanad type. At the enlarging stage, the embryo began the accumulation of starch and protein sequentially. The primary endosperm nucleus began to carry on mitosis 8h after anthesis. The development of endosperm was designated as nuclear type. The endosperm started to degenerate as the embryo grew up to fill almost the whole embryo sac and disintegrated completely but with a thin layer of remains left when the embryo matured.