Abstract:Observations were made of the fertilization and embryo development in intergeneric cross between Triticum aestivum L. cv. Chinese Spring and Leyrnus 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 I seed was obtained from 150 wheat ftorets 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.