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以秋水仙素加倍的同源四倍体水稻三系株系具有高比率的变异胚囊.各种胚囊变异类型在抽穗前1~2d的主穗和第一分蘖穗中出现频繁,造成正常胚囊的比率大幅降低.按变异胚囊的结构特点和形成方式,变异胚囊分为4种类型:退化型、结构变异型、无融合生殖型和反足细胞增殖型.退化型胚囊包括小胚囊和完全退化胚囊,前者仍有较小的胚囊腔而后者胚囊腔缺失;结构变异包括八核七细胞结构的缺失、重复和位置异常,反映了蓼型胚囊典型结构不同形式的变异;无融合生殖胚囊发生比率极低,主要包括反足胚和卵细胞胚;反足细胞的增殖比较频繁,这导致四倍体胚囊的多样性进一步增加,也对结实性带来一定影响.相关分析表明,同源四倍体水稻结实主要来自3部分:正常胚囊、正常型小胚囊和反足细胞增殖型胚囊.这3种胚囊可能具有较好的育性,其对结实率的贡献程度分别为正常蓼型胚囊的72.44%,正常型小胚囊的15.12%,反足细胞增殖型胚囊的12.44%;完全退化型胚囊和位置异常型胚囊对结实率分别表现出显著和极显著的负相关,表明二者可能是结实性的抑制因素
The autotetraploid rice lines doubling with colchicine had a high percentage of mutagenized blastocysts.The variety of embryo sac variant occurred frequently in the main ear and the first tillering ear 1 ~ 2 days before heading, resulting in normal The ratio of embryo sacs is significantly reduced.According to the structural characteristics and formation of the variant embryo sacs, the variant embryo sacs are divided into four types: degenerative type, structural variant type, apomixis type and antipodal cell type.Degenerative embryo sacs include Small embryo sac and completely degenerated embryo sac, the former still has a smaller embryo sac and the latter embryo sac cavity is absent; structural variations include the deletion, duplication and location of the eight-nuclei seven-cell structure, reflecting the typical structure of Polygonum type embryo sac Form of variation; the incidence of apomixis is very low, mainly including anti-foot embryo and egg embryo; anti-podocyte proliferation more frequently, which led to further increase in tetraploid embryo sac diversity, but also brought about by the strong The correlation analysis showed that the autotetraploid rice mainly comes from three parts: the normal embryo sac, the normal small embryo sac and the antipodocyte proliferative embryo sac.The three embryo sacs may have better fertility, Its contribution to the rate of seed setting respectively 72.44% of normal polygamous embryo sac, 15.12% of normal small embryo sac and 12.44% of antipodal proliferating embryo sac, respectively. Completely degraded embryo sac and abnormal embryo sac showed significant and extremely significant Negative correlation, indicating that both may be a strong inhibitory factor