小麦与赖草远缘杂交的受精和胚胎发育

对小麦（Ｔｒｉｔｉｃｕｍ ａｅｓｔｉｖｕｍ Ｌ．）和赖草（Ｌｅｙｍ ｕｓｓｅｃａｌｉｎｕｓＴｚｒｅｌ．）杂交的受精和胚胎发育进行了观察．赖草花粉在小麦柱头上萌发良好，花粉管可顺利长入花柱和胚囊，在检查过的３１９个小麦子房中，６２个（１９．４４％ ）发生了双受精，产生了胚和胚乳，但胚乳的发育往往落后于胚的发育；４９个（１５．３６％ ）发生了单卵受精，只产生胚而无胚乳；７个（２．１９％ ）发生了单极核受精，只产生胚乳而无胚．小麦×赖草虽然总受精率可高达３６．９９％ ，然而由于胚乳的缺乏或发育不完全，致使最后结实率很低．从１５０朵授过赖草花粉的小麦颖花中，只得到１粒种子．表明利用胚培养技术对杂种胚进行早期离体培养，可望提高杂种植株的获得率

FERTILIZATION AND EMBRYO DEVELOPMENT IN HYBRIDIZATION BETWEEN WHEAT AND LEYMUS

Observations were made of the fertilization and embryo development in intergeneric cross between Triticum aestivum L. cv. Chinese Spring and Leymus secalinus Tzrel. The pollen germination of Leymus secalinus appeared normal on the stigma of Triticum aestivum and the pollen tubes grew into the style and entered the embryo sacs. Double and simple fertilization were observed in the pollinated florets. Of the 319 ovaries examed 62 (19.44%) had double fertilization and had embryo and endosperm, but endosperm development was slower than that of the embryos, 49 (15.36%) had only embryo and 7(2.19%) had only endosperm. The total percentage of fertilization was as high as 36.99%. However, only 1 seed was obtained from 150 wheat florets pollinated with Leymus secalinus. This was obviously due to the absence or poor development of the endosperm. It may be suggested that the potential of increasing the frequency of hybrid plant obtainment was great in the cross between wheat and leymus, if embryo culture technique is employed at the early stage of hybrid embryo development.