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1.
M. Leflon    A. Hüsken    C. Njontie    S. Kightley    D. Pendergrast    J. Pierre    M. Renard    X. Pinochet 《Plant Breeding》2010,129(1):13-18
At the field scale, the co-existence of different farming production systems requires strategies to prevent gene flow between adjacent crops. Oilseed rape produces pollen dispersed by wind and insects and the risks of pollen mediated gene flow are significant for this crop. Cleistogamy, the trait of non-opening flowers, could be used to reduce pollen flow. Cleistogamous oilseed rape genotypes were obtained by INRA in France and were bred in order to improve the stability of this trait. In this paper, we examine the reliability of the cleistogamous trait for two inbred lines. The flower opening level was measured at different dates during the flowering period in six field experiments (three sites × 2 years). The results showed that some flowers were partially opened with rates varying from 0.5% to 33% principally depending on genotypes, trials (site and year) and recording dates. Given that other studies have shown that cleistogamy could reduce pollen dispersal, we consider that, even when partially unstable, cleistogamy could be beneficially used in combination with other means in a containment strategy.  相似文献   

2.
Summary The aim of this study was to evaluate the interest of beginning the selection process on a new genetic characteristic, cleistogamy, to manage gene flow in oilseed rape. The first step was to introduce this characteristic in an existing model of gene flow between oilseed rape populations in time and space, GeneSys-Rape. The second step was to evaluate the parameters of the model linked to this characteristic using field experimentations. Cleistogamous oilseed rape was shown to have an autogamy rate as high as 94% and to emit 10 times less pollen than an open-flowered oilseed rape in the same conditions. But the cleistogamous character was also shown to be unstable in the genotypes tested. The third step was to evaluate the interest of cleistogamy using simulations comparing several genotypes with or without cleistogamy in two different cropping systems. These simulations showed that an oilseed rape both dwarf and cleistogamous was interesting to limit gene escape and that a 99%-autogamous oilseed rape was interesting to limit both gene escape from and harvest contamination of the 99%-autogamous oilseed rape.  相似文献   

3.
In this paper, we described the breeding of transgenic rice restorer line for multiple resistance against bacterial blight, striped stem borer (SSB) and herbicide by conventional crossing of two transgenic parental lines transformed independently with different genes. Two stable transgenic rice lines used as donor parents were developed, one was Zhongguo91 which contained cry1Ab gene (for insect resistance) and bar gene (for tolerance of herbicide), and the other was Yujing6 which contained Xa21 gene (resistance to bacterial blight). The elite restorer line Hui773 was used as recipient and crossed with the two stable transgenic rice lines. Then five successive backcrosses were made using Hui773 as recurrent parent. Two rice elite restorers, T773-1 expressing cry1Ab and bar genes and T773-2 expressing Xa21 gene, were obtained, which were confirmed by PCR analysis and testing selectable marker genes in the hybrid progenies. The cross was made between T773-1 and T773-2 to select stable restorer line carrying Xa21, cry1Ab and bar genes. Finally, we obtained transgenic restorer line T773 with good agronomic traits and obvious multiple resistance to Xanthomonas oryzae pv. oryzae, striped stem borer (Chilo suppressalis) and herbicide. The hybrid F1 generation produced from the cross between transgenic restorer line T773 and a corresponding male sterile line Zaohua2A maintained obvious resistance to rice bacterial blight, rice leaffolder and striped stem borer, and showed significant heterosis. Our results indicate that it is feasible to develop transgenic hybrid rice cultivar through breeding transgenic restorer lines.  相似文献   

4.
Helianthus argophyllus is a wild species known as “silver sunflower”, which possesses several traits, including morphological traits that increase drought tolerance. Therefore, introgressions between chosen cultivated lines and two H. argophyllus accessions were made, and segregating generations were established. Important agronomic traits including single heading, high pollen fertility, silver canopy (indicating more cuticular wax), and content of cuticular waxes and oil were selected over six segregating generations. The resulting F6 lines showed introgression of water saving traits, as they had lower excise leaf water loss, with comparable yield to standard checks. However, these F6 lines were late maturing and showed poor flowering synchronization between the cultivated and introgressed lines. Introgressed line “D‐22” was particularly promising as a breeding line, with superior agronomic and drought resistance traits. This line had the potential to be used as an inbred parental line for introgression of drought resistance traits into elite sunflower germplasm. Combining ability analysis of the introgressed lines further showed their potential for heterosis breeding or to be used as parental lines in breeding programme.  相似文献   

5.
6.
以转Cry1Mb基因的水稻株系TS.9(后命名为克螟稻)为种质,与优良亲本杂交,在分离世代,通过与目标基因紧密连锁的潮霉素抗性作为筛选标记,结合田间农艺性状选择,获得目标基因位点纯合的新品系。Cry1Mb蛋白含量检测结果表明大多数新品系携带的靶基因在经杂交重组、自交纯合后保留了原亲本高效表达的特性。抗虫鉴定结果表明,对二化螟(Chilo suppressalis)、稻纵卷叶螟等(Cnapha locrocis medinalis)鳞翅目害虫表现高抗性能,同时,在株高、生育期、产量构成因子等重要农艺性状上也有显著改良。从而,对转基因水稻种质的育种利用途径和选择方法作了有益探索。  相似文献   

7.
Summary Although wild oats (Avena fatua L.) have been considered a potential source of genes for cultivated oat (Avena sativa L.) improvement, most progenies of A. sativa/A. fatua crosses have weak straw and are very susceptible to crown rust (Puccinia coronata CDA. var. avenae Fraser and Led.). Backcrossing to A. sativa has been suggested as a method of improving progeny lines while introducing new genes from wild oats to cultivated oats. In this study, A. sativa/A. fatua F1 hybrids were backcrossed twice to A. sativa, and lines from three backcross populations were selected on the basis of agronomic performance in segregating generations. The A. sativa recurrent parents were Dal (tall and late) and Stout (short and early).Backcross lines and recurrent parents were evaluated in five performance trails from 1983 through 1985. There was significant variation among backcross lines for most traits, but most backcross lines did not produce higher grain and straw yields than their A. sativa parent. Several backcross lines were higher than their recurrent parent in test weight and groat percentage. A line derived from Stout, 175BC2-6, was considered the most promising backcross line in the study. This line produced more grain, had heavier kernels, and headed 3.3 days earlier than Stout. Although 175BC2-6 does not have sufficient straw strength and crown rust resistance to be released as a cultivar, it is considered to be a new source of high grain yield, high test weight and earliness for oat breeding.  相似文献   

8.
本研究采用杂交和分子标记辅助选择技术,将亲本材料P2的水稻广谱高抗稻瘟病基因Pi-9(t)导入杂交水稻恢复系泸恢17,再利用抗稻瘟病基因Pi-9(t)的特异分子标记pB8检测该目的基因,获得68份携有Pi-9(t)基因型的回交株系。基因型鉴定表明株系WR1023、WR1043、WR1056和WR1062为均含有Pi-9(t)基因纯合的回交后代株系。表型分析表明WR1023和WR1056株系农业性状已稳定,且其株叶型、抗稻瘟病及配合力较好,我们认为可以用作育种抗性亲本材料。  相似文献   

9.
Transgenic photo-thermo sensitive genic male sterility Oryza sativa L. cv. “261S” plants with the anti-Waxy gene were successfully obtained using an Agrobacterium tumefaciens-mediated co-transformation method. Marker-free homozygous transgenic lines with the anti-Waxy gene were obtained. The setting seed rates of the transgenic plants via self-pollination or via crossing with the restorer line WX99075 rice and the 1000-grain weight of the transgenic plants and the F2 hybrid seeds obtained by crossing the transgenic or non-transgenic plants with the restorer line WX99075 rice, and the number of panicles of the transgenic plants and yields of the F2 hybrid rice, were analysed. Quality indexes of the transgenic plants and of the F2 hybrid seeds were analysed. Our researches results indicate that hybrid female and hybrid descendant edibility could be improved via the introduction of the anti-Waxy gene, but the grain yields of the reserve seeds via self-pollination of the transgenic photo-thermo sensitive genic sterile lines and of the hybrid rice were not affected.  相似文献   

10.
分子标记辅助选择Xa23基因培育杂交稻抗白叶枯病恢复系   总被引:7,自引:1,他引:6  
水稻抗白叶枯病新基因Xa23抗谱广、抗性强,被定位在第11染色体上。以携带抗白叶枯病基因Xa23的抗病品系CBB23为抗源,以优良杂交稻亲本9311和1826为受体材料,采用杂交和复交,在分离群体中利用与Xa23紧密连锁的EST标记C189进行分子标记辅助选择,通过苗期分子标记检测和成株期农艺性状选择,获得160份目标基因纯合且农艺性状稳定的株系。使用鉴别菌系P6,采用人工剪叶接种法,在苗期和孕穗期对21份重点株系进行了抗性鉴定,所有株系在苗期和孕穗期都表现抗病。同时对3个不育系与其中5个株系配制的15个杂交组合进行了抗性鉴定,所有组合在苗期表现抗或中抗,在孕穗期表现抗。对其中6个杂交组合进行了品比试验,2个组合产量略低于对照两优培九,其余4个组合的产量均高于两优培九,用于测配的3个株系C6201、C6271和C6351有望作为杂交稻恢复系在生产中应用。研究表明在育种进程中利用与Xa23基因紧密连锁的分子标记C189开展抗白叶枯病分子标记辅助育种是一种有效的途径。  相似文献   

11.
以携带抗纹枯病QTL qSB-9TQ的籼稻品种特青和携带抗条纹叶枯病基因Stv-bi的粳稻品种镇稻88为优良等位基因供体亲本,江苏省推广的粳稻品种武育粳3号和武粳15为受体亲本,分别杂交并连续回交。在回交及自交分离世代,利用开发的覆盖目标基因区间的双侧分子标记对目标基因进行辅助选择。至回交BC4F1世代,同一遗传背景2个回交方向的中选单株间聚合杂交,获得2个目标基因位点均纯合的聚合F3株系。条纹叶枯病抗性鉴定和纹枯病抗性接种鉴定结果表明,聚合株系对条纹叶枯病均表现抗病;以0~9级评级标准评价,聚合株系的纹枯病较相应的轮回亲本分别低1.1~1.6级和0.8~1.4级。结合回交低世代抗性鉴定结果分析,自行开发的分子标记对目标基因的辅助选择是有效的。讨论了抗纹枯病育种及分子标记辅助选择聚合育种的相关问题。  相似文献   

12.
Ogura cytoplasmic male sterility (Ogu-CMS) is widely used in the production of commercial hybrids of Brassica oleracea. However, the widespread application of the Ogu-CMS system in B. oleracea has hindered the germplasm innovation of Ogu-CMS resources due to the lack of a natural restorer line. Previously, the Ogu-CMS fertility-restored interspecific hybrids between rapeseed 15Y403 (2n = 38, AACC) and Chinese kale JL1 (2n = 18, CC) have been successfully produced. However, these progenies, which still contained a large proportion of rapeseed genomic components, showed poor fertility and a low seed setting rate under natural pollination. To improve fertility and seed setting, a successive backcross with JL1 was performed to produce BC2 progenies. Screening with the Rfo-specific marker, five individuals harboring the Rfo gene were identified among 98 BC2 progenies. These five individuals underwent background marker screening and an evaluation of agronomic traits and fertility. One individual (code: 15Q23) was identified with higher pollen viability, better seed setting under natural pollination, and a closer genetic background to the parent Chinese kale JL1. Many morphological traits showed no significant differences (P < 0.05) between 15Q23 and the backcross parent JL1. However, the average seed setting of 15Q23 under natural pollination was 0.72 seeds per pod, which was 50 times higher than that of BC1 progenies, and the average pollen viability was 87.07%, which was significantly better than that of the F1 and BC1 plants (P < 0.01). The genetic background of 15Q23 was more closer to the parent JL1 than that of BC1 plants and another BC2 fertility-restored individual, with 82% of the polymorphic alleles being the same as those of the parent Chinese kale JL1. Thus, the individual 15Q23 could be used as a donor plant for further backcrosses. This study lays the foundation for the development of Ogu-CMS restorer material in B. oleracea.  相似文献   

13.
To identify quantitative trait loci (QTLs) associated with the primary target traits for selection in practical rice breeding programs, backcross inbred lines (BILs) derived from crosses between temperate japonica rice cultivars Nipponbare and Koshihikari were evaluated for 50 agronomic traits at six experimental fields located throughout Japan. Thirty-three of the 50 traits were significantly correlated with heading date. Using a linkage map including 647 single-nucleotide polymorphisms (SNPs), a total of 122 QTLs for 38 traits were mapped on all rice chromosomes except chromosomes 5 and 9. Fifty-eight of the 122 QTLs were detected near the heading date QTLs Hd16 and Hd17 and the remaining 64 QTLs were found in other chromosome regions. QTL analysis of 51 BILs having homozygous for the Koshihikari chromosome segments around Hd16 and Hd17 allowed us to detect 40 QTLs associated with 27 traits; 23 of these QTLs had not been detected in the original analysis. Among the 97 QTLs for the 30 traits measured in multiple environments, the genotype-by-environment interaction was significant for 44 QTLs and not significant for 53 QTLs. These results led us to propose a new selection strategy to improve agronomic performance in temperate japonica rice cultivars.  相似文献   

14.
Seed storability in rice (Oryza sativa L.) is an important agronomic trait. Two segregating populations with N22 (indica) as a common parent, viz. a set of 122 backcross-inbred lines (BILs) derived from the backcross Nanjing35 (japonica)/N22//Nanjing35 and another population comprising 189 recombinant inbred lines (RILs) from the cross of USSR5 (japonica) and N22, were studied to detect quantitative trait loci (QTL) controlling seed storability. Germination percentage (GP) was used to evaluate seed storability after aging treated under three different conditions, viz. natural, artificial and combined aging treatments. A total of seven QTLs were identified on chromosomes 1, 2, 5, 6 and 9. Among them, a major QTL, qSSn-9, was common in the two populations. In contrast, four QTLs (qSSnj-2-1, qSSn-2-2, qSSn-5 and qSSn-6) were detected in BILs and the QTL qSSn-1 was identified in RILs, which was a new QTL for seed storability. The N22-derived alleles increased the seed storability at all the loci except qSSnj-2-1. We also investigated the effect of QTLs using five selected lines with high storability from BILs and verified qSSn-5 with a near-isogenic line (NIL). These results provide an opportunity for pyramiding or map-based cloning major QTLs for seed storability in rice.  相似文献   

15.
Inheritance of cleistogamic flowering in durum wheat (Triticum durum)   总被引:1,自引:0,他引:1  
Summary Generally durum wheat flowers are chasmogamous but very rarely, cleistogamy may be observed. Genetic studies based on six crosses and back crosses showed that chasmogamy was determined by a single dominant gene Cl, plants homozygous for the recessive allele, cl, were cleistogamous. The flowering behaviour phenotypes were unaffected by environmental conditions. Cleistogamy was attributed to poorly developed lodicules and stiff perianth.  相似文献   

16.
以珍汕97B和9311为背景的导入系构建及其筛选鉴定   总被引:9,自引:0,他引:9  
以我国主要推广的优良杂交稻亲本(珍汕97B和9311)为受体亲本,以从国际合作网络所征集的品种资源150多份为供体材料,进行了大规模杂交、3-4次回交,1~2次自交,培育珍汕97B和9311为背景的近等基因导入系近5000多份。通过对导入系材料进行品质、耐盐、耐旱、磷高效、氮高效利用等性状的筛选鉴定,获得了大量目标性状的导入系。通过对品质性状导入系的基因型分析,定位了影响粒型的15个染色体区段(或基因)。同时,构建了一套来源于粳稻日本晴的单片段导入系群体。创建的近等基因导入系(群体)为目标基因的发掘、新品种的培育提供重要的材料基础。  相似文献   

17.
利用MAS手段改良恢复系R838稻瘟病抗性研究   总被引:1,自引:1,他引:0  
为了提高杂交水稻恢复系R838稻瘟病的抗性水平,利用MAS手段将抗稻瘟病基因pigm导入目标受体,通过连续多代回交并对其回交后代进行分子标记检测或稻瘟病抗性表型鉴定。筛选回交高世代群体自交,并用三系不育系进行测配。结果表明:F1目标基因占有率为52.4%,随着回交世代的增加,其所含目标基因的占有率稳定在50%左右,通过回交高世代群体苗瘟表型鉴定,苗叶瘟抗性3~9级,株系间差异明显;用三系不育系配组,F1苗叶瘟抗性随入选父本抗性提高而提高,且农艺性状与R838基本保持一致。因此,通过分子标记辅助育种技术,用pigm稻瘟病抗性基因改良目标受体的稻瘟病抗性是一个有效途径。  相似文献   

18.
转基因水稻的研发以及环境释放,外源基因通过花粉逃逸到野生近缘种中,可能带来的生态效应愈来愈受到人们的关注.本研究采用人工杂交技术将CrylAc/CpTI双价抗虫基因从转基因栽培稻渗入普通野生稻(Oryza rufipogon Griff.)中,获得普通野生稻F1及分离后代F2、F3、F4、F5和回交后代BC1F1和BC...  相似文献   

19.
Marker assisted backcrossing has been used effectively to transfer the submergence tolerance gene SUB1 into popular rice varieties, but the approach can be costly. The selection strategy comprising foreground marker and phenotypic selection was investigated as an alternative. The non-significant correlation coefficients between ranking of phenotypic selection and ranking of background marker selection in BC2F1, BC3F1 and BC3F2 generations indicated inefficiency of phenotypic selection compared to marker-assisted background selection with respect to recovery of the recipient genome. In addition, the introgression size of the chromosome fragment containing SUB1 was approximately 17 Mb, showing the effects of linkage drag. The significant correlation coefficient between rankings of phenotypic selection with the percentage of recipient alleles in the BC1F1 generation suggested that background selection could be avoided in this generation to minimize the genotyping cost. The phenotypically selected best plant of the BC3F1 generation was selfed and backcross recombinant lines were selected in the resulting BC3F4 generation. The selection strategy could be appropriate for the introgression of SUB1 QTL in countries that lack access to high-throughput genotyping facilities.  相似文献   

20.
Search for male sterility-inducing cytoplasm in wild species of the genus Oryza was attempted with a view to diversify the base of the cytoplasmic genetic male sterility system currently used in the development of commercial rice hybrids. A total of 132 interspecific crosses were made involving accessions of four wild and two cultivated species, all belonging to the A genome. Wild accessions possessing sterility-inducing cytoplasms were identified following reciprocal and sterile F2 backcross methods. Sterile segregants were pursued through substitution backcrosses to develop cytoplasmic male-sterile (CMS) lines. CMS lines were developed with the cytoplasm of either O. rufipogon (VNI) or O. nivara (DRW 21018, DRW 21001, DRW 21039, DRW 21030 and RPW 21111). Based on shape, staining, and abortive pattern of pollen and also on type of interaction with a set of restorers and maintainers for known cytoplasmic male steriles of WA source (V 20A), the newly-developed CMS lines were grouped into four classes. Of these, RPMS 1 and RPMS 2 showed gametophytic male sterility with a restorer reaction different from WA cytoplasmic male-sterile stocks.  相似文献   

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