Inheritance of Fertility Restoration for Cytoplasmic Male Sterility in a New Gossypium barbadense Restorer

In order to clarify inheritance mechanism of fertility restoration for cytoplasmic male sterility （CMS） in a new Gossypium barbadense restorer line Hai R which was found in the fertility test crossing of G. hirsutum CMS lines with G. barbadense germplasms. 23 fertility segregation populations of F2 and backcross were used to analyze the inheritance of fertility restoring gene（s） of Hai R. The result showed that Hai R had one major dominant gene （RfB） to control the CMS fertility restoration and this fertility restoration gene functioned at the sporophytic level. The sterile cytoplasm background might not only influence the transmission rate of male gamete but also that of female gamete when the restorer gene was recessive. It could be deduced that this fertility restoration gene might come from G. harknessii cotton, Hai R is of value in the application of cotton interspecific hybrid breeding.

Breeding for Male-Sterility Line with G. barbadense Nuclear Background and Cytological Observation of Its Microsporogenesis

To study the feasibility of utilizing the heterosis of interspecific （Gossypium barbadense x G. hirsutum） hybrid cotton based on cytoplasmic male-sterility system, a G. barbadense male-sterility line HaiA with G. harknessii cytoplasm and its maintainer HaiB were developed by replacing nuclear genome from G. hirsuturn to G. barbadense in a backcross breeding program. Its male cell abortion was observed using a light microscope through a paraffin slice for H.E staining technique. The results showed that the abortion characteristics in HaiA were not significantly changed at the cytological level, although G. hirsuturn nuclear genome of sterile line was replaced by G. barbadense nuclear genome, and its abortion mainly took place at the stage of the microspore mother cell meiosis. HaiA sterility was very stable because of its early abortion and no-pollens in anthers. Hybrids between HaiA and G. hirsuturn restorers were high in pollen viability, boll setting rate, boll weight and lint percentage which contributed to high yield heterosis. It is suggested that HaiA is of great value in the application of cotton interspecific hybrid seed production.

细胞质雄性不育海岛棉的选育和细胞学观察

【目的】利用细胞质雄性不育海岛棉和陆地棉种间的杂种优势。【方法】采用回交育种技术,选育了一套具有哈克尼西棉细胞质的海岛棉不育系“海A”和保持系“海B”,并用石蜡切片的方法对所选育的海岛棉不育系和保持系的小孢子发生进行了细胞学观察。【结果】育成的海岛棉不育系,虽然核背景由陆地棉被置换成了海岛棉,但败育的基本特征没有发生明显改变:“海A”的败育时期主要在小孢子母细胞减数分裂时期,花药无花粉粒,具有败育早、稳定和不受环境影响的特性;“海A”与陆地棉恢复系杂交,杂种F1花粉育性好,结铃率高,铃重增大,衣分提高。【结论】选育的“海A”在海岛棉与陆地棉种间杂种优势利用研究中具有良好的利用前景。

Wnafstu棉花雄性不育系遗传类型研究

以中棉所41、陕7359(系)、陕2089(系)、陕2234、陕024(系)5个陆地棉种质和8046-1、8046-2、8046-3三个与不育系具相同遗传背景的可育种质为测试父本,采用连续多代和多父本分别株对株测交,对西北农林科技大学发现的暂定名Wnafstu的雄性不育系进行研究。结果表明,5个陆地棉种质父本与不育系测交后,子代均为100%不育株;3个与不育株具相同遗传背景的可育株分别与不育株测交后,子代有不育和可育株两种类型,分离没有规律。据此认为,该不育系属细胞质雄性不育类型。一般陆地棉种质与其杂交,都可保持其不育性。与其具相同遗传背景的可育种质对不育系育性有恢复功能。提出了对该不育系下一步研究的方向。

细胞质雄性不育海岛棉恢复系恢复基因的遗传分析

【目的】在陆地棉细胞质雄性不育系与海岛棉种质材料进行测恢筛选时,选得一个对不育有恢复力的海岛棉材料"海R",本研究的目的是了解其育性恢复的遗传方式。【方法】构建23种不同的F2群体和回交群体,分析和明确恢复基因的遗传。【结果】"海R"恢复基因属孢子体遗传,由一个主效显性基因(RfB)控制。在恢复基因呈隐性时不育胞质不但对雄配子的传递有影响,而且对雌配子的传递也有影响。【结论】推测此海岛棉恢复系的育性恢复基因来源于哈克尼西棉基因组,在陆地棉与海岛棉的种间杂种优势利用中具有应用价值。