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41.
雄性不育是水稻杂种优势利用的重要资源,对雄性不育现象的研究具有重要理论意义和实践价值。本研究以自然突变的水稻雄性不育突变体012S-3为试验材料,对其表型特征和花粉育性等进行调查,并构建遗传群体,利用分子标记对目的基因进行初步定位,然后应用基因组重测序技术对其进行精细定位。结果表明,012S-3是一个典型的无花粉普通型雄性不育材料,其不育性状受1对隐性核基因控制。初步定位分析目的基因与SSR标记RM6081存在连锁关系,其遗传距离约为34.4 c M;进一步的精细定位分析,找到3个候选基因:LOC_Os07g35880、LOC_Os07g35920和LOC_Os07g35940,其中LOC_Os07g35880和LOC_Os07g35940编码β-淀粉酶,属于水稻中新发现的花粉致死基因。该不育基因的成功定位为其进一步的分离克隆及其在水稻分子设计育种中的应用奠定了基础。 相似文献
42.
43.
Summary Six partially resistant spring barley cultivars were exposed to four barley leaf rust (Puccinia hordei) races in the field and in the greenhouse. The 24 cultivar-race combinations were tested in field plots of 1.5×1.5 m2 in two replications over two years. To reduce the interplot exchange of urediospores each plot was surrounded by winter rye.The level of barley leaf rust varied among cultivars, races and years. In both years the variance for cultivar-race interactions was highly significant and originating largely from the cultivar-race combinations Berac-22. Armelle-22, Armelle-A and Tyra-A. The Berac-22 interaction was towards higher, the other three interactions towards a lower level of barley leaf rust. The reduced rust levels of these three combinations were not due to interactions between the partial resistance of these cultivars and the aggressiveness of the races but to major genes for hypersensitivity not effective to the races 1-2-1 and F, common in Western Europe, but effective against the rare races 22 and A. This was revealed in the greenhouse experiments where all combinations had a susceptible infection type except Armelle-22, Armelle-A and Tyra-A, which showed low infection types in both the seedling and adult plant stages. The urediosori present in the field plots of these three combinations apparently arose from spores derived from other plots; this interplot interchange suggesting partial resistance.The interaction of Berac with race 22 truly was a small race-specific effect within the polygenic, partial resistance of barley to barley leaf rust like the one reported before between Julia and race 18. 相似文献
44.
Genetics of thermosensitive genic male sterility in rice 总被引:4,自引:0,他引:4
Summary Inheritance of thermosensitive genic male sterility (TGMS) in Norin PL12 and IR32364TGMS and their allelic relationship were studied from F1, F2 testcross (TC) and F3 generations of the crosses made with the two mutants and several fertile tester parents. F2, TC and F3 segregation behavior for pollen and spikelet fertility indicated that the TGMS trait in the two mutants was controlled by a single recessive gene. Allelic relationship studies indicated that TGMS genes of the two mutants were different. Since TGMS gene in Norin PL12 has been designated as tms
2
, the TGMS gene present in IR32364TGMS is tentatively designated as tms
3
(t) until allelic test is done with another TGMS gene (tms
1
) reported from China in a line 5460S seeds of which were not available. 相似文献
45.
甘蓝型(Brassica napus L.)显性核不育双低油菜杂交新品种核杂 3号的选育 总被引:5,自引:0,他引:5
以甘蓝型油菜显性核不育杂合型不育株204A与恢复系83248为材料,通过杂交、自交、兄妹交和测交等育种方法,成功地转育成双低纯合两型系48AB。然后在显性核不育三系技术基础上,用纯合两型系48AB与临保系C1按核不育二系法生产全不育系(48A×C1)CA,再用该系与恢复系RH-5杂交选育成显性核不育双低油菜杂交品种核杂3号。该杂交品种不仅产量优势显著,而且双低品质优良。 相似文献
46.
从胚胎学方面研究了粘果山羊草细胞质的小麦雄性不育系K83(21)35A与保持系83(21)35B杂交的双受精过程,胚和胚乳的发育特点,以及单倍体胚和孪生胚发生的规律。结果表明:双受精过程、胚和胚乳的发育与普通小麦自交相似。n型单倍体胚来自助细胞的孤雌生殖;n-n型双胚来自助细胞和卵细胞的孤雌生殖;2n-n型双胚中的单倍体胚来自助细胞,二倍体胚来自受精卵。适当延迟授粉,能提高单倍体发生的频率。 相似文献
47.
利用新选育出的质核互作型雄性不育系和筛选出的恢复系配制杂种,研究了恢复系恢复基因的恢复能力,并从杂种后代表现讨论了强优势组合的选配应注意的问题。 相似文献
48.
小麦光敏不育系皖901S研究初报 总被引:2,自引:0,他引:2
皖9015是安徽省农科院作物研究所发现并育成的一个新型光敏感型雄性不育系。该材料在合肥地区(N31°51°)短日低温条件下表现为全不育,在长日温暖条件下表现正常可育。在小麦正常发育的温度范围内,其育性转换过程随光周期的变化而发生,光周期对育性的影响远大于温度的影响。与其他类型雄性不育材料比较,皖901S通过长日条件下自交更易保持,且短日条件下育性表现稳定,雄性败育彻底,并能为大多数普通小麦品种所恢复。皖901S的两系杂种F1代优势明显,它的育成为小麦杂种优势利用开辟了一条新途径。 相似文献
49.
ZENG Han-lai ZHANG Duan-Pin ZHANG Zhi-yu YI Wen-kai ZHU Xin MENG Hui-jun 《中国农业科学(英文版)》2002,1(5):481-485
Peiai64S, an indica male sterile rice with a male fertility alteration under different environments, is selected from the offspring of indica rice crossed with Nongken58S. Nongken58S, a japonica photoperiod sensitive genic male sterile rice (PGMS), deriving from a natural mutant plant individual of normal japonica rice variety, Nongken58, is used as a male sterile gene donor of Peiai64S. But Peiai64S is not a typical PGMS rice, the male fertility is sensitive to temperature just as thermo-sensitive genic male sterile rice (TGMS). We have selected typical PGMS plants in F2 population of Peiai64S × Nongken58, whose ratio of fertile plants to sterile plants is nearly 3:1. The sterility inheritance conformed to one pair of gene segregation model. The result indicates the main male sterile gene in Peiai64S is not other than the PGMS gene, and comes from Nongken58S. The genetic background affects effective expression of the PGMS gene. This suggests that we ought to focus on optimizing the genetic background of the PGMS gene in PGMS rice breeding, and select an ideal genetic background as a transgenic background in molecular breeding. 相似文献
50.
光温敏核不育水稻的育性及花药的发育解剖学研究 总被引:5,自引:0,他引:5
采用形态解剖学的方法比较观察了6个光温敏雄性不育水稻品种的花药发育状况,并从始穗期起抽检花粉育性,结果表明,各不育水稻的雄蕊发育第5期的绒毡层细胞均明显小于对照品种,细胞质也不浓厚;药幅维管束的导管、筛管管腔较小,维管束鞘细胞较小。在花药发育的第8期,药隔维管束的韧皮部和木质部的界限仍不明显,药壁较厚。 相似文献