【作者】 周在为；

【导师】 李新奇；

【作者基本信息】 中南大学 ， 作物遗传育种， 2010， 硕士

【摘要】 杂种优势利用是大幅度提高作物产量的重要途径。雄性不育资源的获得是实现强优组合选育的重要基础,利用雄性不育系能大大提高杂种种子产量和质量。培育和推广广适性的超级杂交稻新组合,大幅度提高单位面积产量,已成为增加水稻总产的关键技术,也是解决我国粮食供求矛盾,保障国家粮食安全的重要出路。本研究应用细胞工程技术花药培养和细胞融合尝试利用新的雄性不育资源,并为水稻优良雄性不育获得保持系开辟路径。获得主要结论如下：1通过田间调查在配子体雄性不育F2代中发现了较大比例的不育株,育性表现分离。这与以往配子体雄性不育F2代一般表现可育的说法不同,显示了雄性不育遗传的多样性,能够对杂交粳稻的研究起到参考作用。上述现象产生的原因可能是由于恢复基因不够,配子体雄性不育F2代中某些植株缺乏恢复基因,产生不育株。2对配子体雄性不育F2代中的不育株进行花药培养,得到了一批育性稳定、败育彻底的花培后代植株。不育株携带的少量微效恢复基因进一步纯合而表达,经过选择而排除掉微效恢复基因,获得不育性稳定遗传,败育彻底的不育后代。说明水稻BT型、HL型等配子体雄性不育同样具有培育出完全雄性不育系的潜力,以配子体雄性不育细胞质为选择背景,经过花药培养就能够得到。3对花培后代完全雄性不育植株和常规粳稻进行不对称细胞融合,利用不育系来获得不育系的同型保持系,是我们设想的反向核代换技术。育种中,一般是通过杂交的方式育成保持系的同时得到不育系。利用反向核代换技术可能为优良配子体完全雄性不育系的选育开辟有效途径。同时还能够缩短了育种周期,丰富不育系资源。融合体目前正在培养观察之中。更多还原

【Abstract】 Heterosis is an important and effective way in increasing crop yield Cultivating and popularizing super hybrid rice combinations significantly increased yield per unit area in China and have become the key way to enhance total rice production. CMS resources are the basis for breeding excellent combinations. Male sterile lines can greatly increase the yield and quality of hybrid seeds. Anther culture and protoplast fusion were used in this study to explore new breeding method to obtain elite completely male sterile lines of gametophyte type. The research results are as fellow:1 A lot of male sterile plants were found in the F2 generation of rice gametophyte. The fertility of F2 was unstable. The phenomenon is different from previous reports. This discovery will enrich the male sterility research. If it is appropriately made use of, it may play an important part in Japonica hybrid rice breeding.2 The male sterility of gametophyte F2 generation was stable by anther culture technique. It showed mini-fertility genes in CMS lines of BT or HL type could be discarded by anther culture. CMS lines of BT or HL type has the potential to become completely male sterile in the future.3 Reverse nuclear substitution technique was designed to obtain the maintainer lines of the elite completely male sterile CMS plants mentioned above. The steps are as follow:irradiate to protoplasts of a normal variety to destroy their nuclear, retain their normal cytoplasm; treat the protoplasts of the CMS plants with iodoacetamide, fuse the two kinds of protoplasts to form cybrid cells and screen fertile plants as maintainers. Cybrid cells were obtained and the results will be get later.更多还原