披碱草 Elymus rectisetus无融合生殖及其转育的研究进展

披碱草Elymus rectisetus(Nees in Lehm）A Loeve et Connor(2n=6x=42），SSYYWW）是目前发现的小麦族（Triticeae）中唯一的无融合生殖种，属二倍性孢子形成的假受精无融合生殖类型，无融合生殖能固定杂种优势，简化育种程序，缩短育种年限，因此E.rectisetus无融合生殖及其向小麦中导入的研究一直受到遗传育种学家的重视，与有性生殖相比，无融合生殖类型大孢子母细胞（MMC）的形成有三个显著特点：（1）MMC在早前期合点形成液泡；（2）MMC核显著伸长，呈椭圆形或哑玲形；（3）MMC周围缺乏含，胼胝质的细胞壁E.rectisetus与披碱草属内的种间杂交取得较大进展，了其分类和遗传学研究。E.rectisetus与近缘属杂交成功例子逐渐增多，目前国内外已成功进行了普通小麦与E.rectisetus属间杂交，为最终将E.rectisetus无融合生殖基因导入小麦奠定了基础。

Progress in apomixis of Elymus rectisetus

Elymus rectisetus (Nees in Lehm) A Love and Connor (2n=6x=42, SSYYWW) is the only apomict found in the Triticeae , which its apomixis is very important for wheat genetic improvement, because apomixis would fix hybrid heterosis of wheat and greatly reduce cost of seed. Compared with the megasporogenesis in the close sexual relative Elymus scabrus, diplospory in E.rectisetus has three traits: (1) megaspore mother cell (MMC) nucleus is grossly elongated, assuming ellipse or bellbar shape; (2) the abnormal formation of chalazal vecuoles during early prophase; (3) the lack of callose deposition within and about the cell walls. Progress of interspecific cross in Elymus contributed to study of their taxonomy and genetics. The intergeneric hybrid F1 between T. aestivum and apomictic E.rectisetus was obtained in U S A and China. BC1 was also obtained from backcross between F1 and T. aestivum. Production of F1 and BC1 will be useful for transferring apomictic gene(s) from E.rectisetus into wheat.