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51.
Inheritance of Partial Male-Sterility in Guar 总被引:1,自引:0,他引:1
R. E. Stafford 《Plant Breeding》1989,103(1):43-46
A partial male-sterility system was found in a released guar, Cyamopsis tetragonoloba (L.) Taub. (2n = 2x = 14), breeding line, TX76-3285. Partially male-sterile plants produce some functional pollen, but with suitable genetic markers may be used to facilitate crossing in breeding programs. In addition, self fertilization allows partially male-sterile plants to be propagated sexually as homozygotes, once placed in breeding lines. The objective of the present study was to determine the inheritance of a partial male-sterility system in guar. Partial male-sterility appeared to be controlled by two genes, with one gene acting in a dominant epistatic manner and the second gene by incomplete dominance. The trait was expressed on every raceme beginning at about 4 to 6 weeks after planting in field-grown plants. The gene symbols, “pms 1” and “Pms 2” are proposed for the new trait. Segregation data indicated that alleles for pubescence segregated independently of alleles for partial male-sterility. Partial male-sterility in guar may be useful in the production of hybrid seed for breeding and genetic research. 相似文献
52.
Phuong Dang Thai Phan Hiroki Kageyama Ryo Ishikawa Takashige Ishii 《Breeding Science》2012,62(3):256-262
The Asian wild rice, Oryza rufipogon, has partial outcrossing behavior and shows high levels of genetic variation. To estimate an accurate outcrossing rate of annual form of O. rufipogon, two backcross lines (Lines R1 and R2) between Oryza sativa Nipponbare and O. rufipogon W630 were examined under field conditions. A chromosome survey confirmed that these lines had wild chromosomal segments at more than 92% of marker loci. As for the traits of glume, stamen and pistil, Line R1 showed similar floral morphology as that of O. rufipogon W630, whereas Line R2 had larger glumes. In 2005, 2006 and 2008, a total of 22 backcross plants were planted in the middle of wild rice plots. The successive progenies of each plant were examined using microsatellite markers that could clearly detect self-pollination and outcrossing. The outcrossing rates of Line R1 plants ranged from 4.04% to 25.50% with an average of 10.20%. This indicates that cross-pollination of wild rice is a chance event affected by many environmental factors. The outcrossing rates of Line R2 plants also varied, however, no significant difference was observed between the averages of Lines R1 and R2, suggesting that the glume sizes are not critical for outcrossing ability. 相似文献
53.
从黄土地区的特殊地质出发,以109国道清水河至十七沟段为试验研究对象,概要地论述黄土地区路基压实施工存在的问题,提出了今后施工具体操作方法及注意事项。 相似文献
54.
大白菜回交导入系群体构建及其遗传分析 总被引:3,自引:1,他引:2
利用大白菜栽培品种的DH系Z16和白菜型油菜自交系L144杂交的F1获得包括119个株系的DH群体。用相同亲本的F1与Z16进行独立回交, 利用25个独立回交的BC2分别得到这些株系的DH系,选择每个BC2的4~6个DH系构建121个株系的BIL群体。进一步利用SSR和SRAP标记构建了DH群体遗传图谱, 由10个连锁群组成, 包括245个分子标记, 总长度714 cM, 平均遗传图距2.9 cM。再以此图谱为参照, 用锚定在染色体上的97个SSR标记研究供体亲本L144的染色体片段在B IL群体中覆盖基因组比率。在BIL群体中来源于L144的基因组片段占0.84% ~35.00% , 平均为11.31% , 接近理论遗传预期值12.50%。在25个BC2的BIL株系中供体亲本L144等位位点占1.69% ~27.36% , 平均为11.03%。 相似文献
55.
56.
利用垂直板聚丙烯酰胺凝胶电泳法对白色力克斯兔(WR)、哈尔滨白兔(HW)及其杂种一代(F_1,♂WR×♀HW)和回交一代[B_1,♂WR×♀F_1包括分离出的力克斯毛型(B_1R)和正常毛型(B_1N)]血液中的红细胞酯酶(Es—1、Es—2和Es—3)、血清转铁蛋白(Tf)、前转铁蛋白(Prt)、后白蛋白(Po)、血红蛋白(Hb)、血清过氧化氢酶(Cat)、血清过氧化物酶(Pod)和红细胞乳酸脱氢酶(LDH)等10个蛋白位点进行了测定.结果表明,Hb、Cat、Tf和LDH呈单态,其他位点呈多态.在多态位点中,Es—1、Es—2、Es—3、Po和Prt分别出现3,3,3,3和6种表型,受2,2,2,2和3个共显性等位基因控制.Pod共有5种表型,在WR群体中只有表型Ⅰ呈单态.x~2检验表明,哈尔滨白兔在Es—1、Es—2、Es—3、Po和Prt5个位点上均处于平衡状态,而其他群体则不同程度出现不平衡状态. 相似文献
57.
4个水稻高产品种与巴西陆稻的耐旱性比较研究 总被引:5,自引:1,他引:4
在营养生长期与生殖生长期分别进行自然干旱与人工气候干旱处理,比较研究了4个水稻高产品种(组合)V989、汕优198、培两优特青及两优681与巴西陆稻IAPAR-9的耐旱性.结果:(1) 当叶片出现永久萎蔫时,4个水稻品种(组合)盆中土壤含水量为6.1%~8.5%,显著或极显著低于IAPAR-9盆中土壤含水量(9.2%);(2)当叶片出现永久萎蔫后3~5 d复 相似文献
58.
Guo Zhijun Zhao Yunlei Chen Wei Wang Hongmei Gong Haiyan Sang Xiaohui Cui Yanli Zhao Pei 《棉花学报》2019,31(4):327-334
[Objective] The aim of this study was to map quantitative trait loci (QTLs) of Verticillium wilt resistance in cotton. [Method]In this study, with the cultivar Lumianyan 28(Gossypium hirsutumL.) as the recipient parent and the F1generation obtained from the cross Hai7124 (G. barbadense) and TM-1(G. hirsutumL.) as the donor parent, an interspecific advanced backcross population was constructed. Compared with the integrated high density genetic linkage map published, simple sequence repeat(SSR) markers of polymorphism were used to construct genetic linkage map. QTLs detection was conducted by composite interval mapping method in field and disease nursery. [Result] 216 simple sequence repeated (SSR) markers of polymorphism were assigned to 26 Chromosomes with a total map distance of 3 380 cM and an average distance of about 15.77 cM between two adjacent markers. Six QTLs located on 6 chromosomes had been detected and could explain phenotypic variance with 8.56%~20.26%. Five of Six QTLs were consistent with the previous study. Moreover, one novel QTL which located on Chromosome 1 was detected in this study. These results maybe helpful for the marker-assisted development of new cultivars which were resistant to Verticillium wilt. [Conclusion] Six QTLs were detected, one of them is a new QTL on chromosome 1. 相似文献
59.
为了对转基因抗虫玉米转育株 Bt 蛋白的表达特性进行分析,用Cry1Ab/Cry1Ac 平板试剂盒定量检测了3种含 Bt 基因的玉米回交后代品系 BC1F1 ( HZ3152、HZ3342、HC0142 ) 在相同生长时期不同组织和不同生长时期相同组织中 Bt 蛋白的表达量。结果表明,在乳熟期 BC1F1 不同组织中 Bt 蛋白表达含量的高低顺序为: 叶片 >胚乳>花丝>种子苞叶;在BC1F1不同的生长发育阶段 ( 苗期、抽丝期和乳熟期 ),叶片中 Bt 蛋白的含量随生育期的推移呈明显先上升后下降趋势, Bt 蛋白含量在抽丝期达到最大,之后又开始下降;苗期 ( HC0142、HZ3152、HZ3342) Bt 蛋白的含量 (4.16、3.75和3.72 μg·g-1 ) 和乳熟期 (5.56、4.58和4.79 μg·g-1 ) 的含量分别是抽丝期 (6.05、5.36和5.50 μg·g-1) 的 68%、69%、67% 和91%、85%、87%。一般在玉米生长后期 Bt 蛋白的浓度有所下降,但幅度不大,对其抗性不会造成太大影响。该研究表明 Bt 蛋白在玉米回交后代中可以稳定表达,对 Bt 的相关研究为转基因育种等提供了参考依据。 相似文献
60.
选用广谱高抗白叶枯病的籼稻IRBB21为抗源供体(Xa-21),抗稻瘟病感白叶枯病的晚粳T91-50为轮回亲本,通过连续回交和花培转育显性抗性基因Xa-21.结果表明,连续回交结合在B2F2中选择偏粳的抗病植株花培,是籼粳亚种间转育抗白叶枯病基因的快速、有效方法,并对连续回交转育显、隐性抗性基因的技术特点、速度和效果进行了比较 相似文献