小麦和无融合生殖小麦草杂交后代(BC_2F_2)的生物学特性及根尖染色体数目变化研究

Studies on the Biological Characteristics and the Variation of Chromosome Numbers in BC 2F 2 between Wheat and Wheat Grass

对小麦 (Triticumaestivum)和无融合生殖小麦草 (Elymusrectisetus)的杂种后代 (BC2 F2 )生物学特性和根尖染色体数目变化情况进行了的研究。结果表明 ,BC2 F2 的生物学特性处于小麦和小麦草之间 ,但更趋向于小麦 ,这是由于杂交后代经 2次回交所致。根尖染色体检查发现 ,BC2 F2 的体细胞染色体数目存在 1个很大的变异范围 ,从 2 9条到 6 9条不等 ,但大部分细胞内的染色体数目是 42条。杂种后代的体细胞染色体数目的变化一方面与远缘杂交有关 。

Studies were been made on the biological characteristics and the variation of chromosome numbers of root tip in BC 2F 2 offsprings between wheat and wheat grass. The hybrid's biological characters are between wheat and wheat grass, but are more closel to wheat because the hybrid was backcrossed twice by wheat. The cytological research revealed that there was a varied range of chromosome numbers (the number is from 29 to 69). The rale of plants with 42 chromosomes was up to 49.3%. The variation of chromosome may have a connection with apomixis.\;