论文部分内容阅读
亚洲栽培稻(Oryza sativa)与高秆野生稻(O.alta)分别属于AA和CCDD染色体组,其种间生殖隔离影响着高秆野生稻的有利基因向栽培稻的转移和利用.本研究从不可交配性和杂种不育性两个方面系统研究了栽培稻与高秆野生稻种间生殖隔离的细胞学机理.结果表明,其不可交配性的细胞学原因在于:(ⅰ)胚囊亲和性障碍,表现为不同程度的受精障碍,包括不受精、受精停滞和单受精等;(ⅱ)杂种不活障碍,表现为杂种胚胎发育停滞以至胚胎夭亡,这是导致不可交配性的主要原因.杂种F1不育包括胚囊败育和花粉败育,其中杂种胚囊完全败育,以胚囊退化为主;杂种花粉高度败育则主要表现为典败;杂种胚囊和花粉败育的细胞学原因主要在于其大小孢子母细胞减数分裂过程的异常,即染色体不育导致了杂种的高度败育.由此提出了克服栽培稻与非AA染色体组野生稻种间生殖隔离的可行办法.
Oryza sativa and O. alta belong to the AA and CCDD genomes, respectively, and their interspecific reproductive isolation influences the transfer and utilization of the favorable genes of high-stalk wild rice to cultivated rice Cytocompatibility between cultivated rice and tall wild rice (Oryza sativa L.) was studied systematically.The results showed that the cytological reasons for its non-malleability were: (i) embryo sac affinity Sexual disorders, manifested as varying degrees of fertility disorders, including insemination, stagnation of fertilization and single fertilization, etc .; (ii) Inhybrid disorders, manifested as stagnant hybrid embryos and embryonic deaths, which are the main causes of non-malaria. Hybrid F1 sterility, including embryo sac abortion and pollen abortion, including hybrid embryo sac completely aborted, mainly to embryo sac degradation; hybrid pollen height abortion is mainly the classic defeat; hybrid embryo sac and pollen aborted cells The main reason is the abnormality of the meiosis of megaspore mother cells, that is, the chromosome infertility leads to the high abortion of hybrids.Therefore, it is proposed to overcome the possibility of reproductive isolation between cultivated and non-AA genome wild rice .