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1.
The present study was carried out with the objective to validate the molecular markers, which have been previously reported to be linked to fertility restorer (Rf) gene(s) for WA-CMS lines of rice. Two mapping populations involving fertility restorer lines for WA-cytoplasm, viz., (i) an F2 population derived from the cross IR58025A/KMR3R consisting of 347 plants and (ii) a BC1F1 population derived from the cross IR62829A/IR10198R//IR62829A consisting of 130 plants were analyzed. Nine SSR and three CAPS markers reported to be linked to Rf genes along with two previously unreported SSR markers were analyzed in the mapping populations. In both the populations studied, the trait of fertility restoration was observed to be under digenic control. Eight SSR markers (RM6100, RM228, RM171, RM216, RM474, RM311, MRG4456 and pRf1&2) showed polymorphism between the parents of the F2 population, while the SSR markers RM6100 and RM474 showed polymorphism between the parents of both the F2 and BC1F1 populations. Only one CAPS marker, RG146FL/RL was polymorphic between the parents of the BC1F1 population. RM6100 was observed to be closely segregating with fertility restoration in both the mapping populations and was located at a distance of ~1.2 cM. The largest phenotypic variation was accounted for the region located between RM311 and RM6100. Using the marker-trait segregation data derived from analysis of both the mapping populations, a local linkage map of the genomic region around Rf-4, a major fertility restoration locus on Chromosome 10 was constructed, and RM6100 was observed to be very close to the gene at a distance of 1.2 cM. The accuracy of the marker RM6100 in predicting fertility restoration was validated in 21 restorers and 18 maintainers. RM6100 amplified the Rf-4 linked allele in a majority of the restorers with a selection accuracy of 94.87%. Through the present study, we have established the usefulness of the marker RM6100 in marker-assisted selection for fertility restoration in segregating populations and identification of restorers while screening rice germplasm for their fertility restoration ability.  相似文献   

2.
H. Ghiasi  K. A. Lucken 《Euphytica》1982,31(1):253-259
Summary Many conventional hard red spring wheat (Triticum aestivum L. em Thell) lines, including several North Dakota cultivars, carry a gene (or genes) which restore partial male fertility to male sterile plants with Triticum timopheevi Zhuk. cytoplasm. Since this gene has no fertility restoration function in T. aestivum cytoplasm, the postulation can be made that it is being retained in conventional lines because of pleiotropic effects, favorable linkages or chance. The research reported in this paper examined these possibilities. Forty F6 lines, derived from a single F2 plant which was heterozygous for a gene (or genes) for partial fertility restoration, were evaluated for two years in a yield trial planted at Fargo, North Dakota. The 40 lines were testcrossed to a male sterile line having T. timopheevi cytoplasm, and the mean seed set of testcrosses was used as a measure of a line's fertility restoration potential. Twenty-seven lines had the gene for partial fertility, and 13 lines apparently lacked this gene. The 40 lines differed for heading date, anther extrusion, plant height, grain yield, 200-kernel weight, test weight, and grain protein percentage. However, comparisons of lines having the restorer gene with those lacking the gene did not provide any obvious explanation for the retention of the partial fertility restorer gene in the breeding stocks of the North Dakota conventional hard red spring wheat breeding program. The possibility that the restorer gene was linked with genes for resistance to stem rust or leaf rust also was evaluated by testing lines for their reaction to several races of rust. No conclusive association was found.Contribution from the Agric. Exp. Sta., North Dakota State University, Fargo, ND 58105, Journal Article no.  相似文献   

3.
W. C. Zhou    Y. H. Zhao    M. L. Zou  S. W. Wang 《Plant Breeding》1999,118(3):221-224
The paper summarizes the selection and improvement of pollen fertility restoration in cytoplasmic male-sterile lines during the past 30 years at Jiangsu Province, China. A fertility restorer line (R16) with a good history of strong and stable restoring ability to different sterile lines was bred by accumulating fertility-restoring genes from derivatives of T797 and other restorer lines such as Primepi. A series of well-performing restorer lines with similar fertility-restoring ability has been bred by improving agronomic characters, disease-resistance and kernel size of R16. The restoring ability of these restorer lines using different male-sterile lines demonstrates that fertility restoration is no longer an obstacle for commercial utilization of hybrid wheat with the Triticum timopheeviii cytoplasmic male-sterile system. Line 2114 is a restorer with a single restoring gene transferred from Aegilops umbellulata. Its restoring ability, using both difficult and easily restored lines was 82% and 93.3% respectively. Maiyou No. 5, one hybrid variety, showed 13.2% yield advantage over the control variety in the Jiangsu Province registration test in 1997-1998 and was superior to nine other varieties adapted to the Jiangsu Province.  相似文献   

4.
The pol cytoplasmic male-sterility system has been widely used as a component for utilization of heterosis in Brassica napus and offers an attractive system for study on nuclear–mitochondrial interactions in plants. Genetic analyses have indicated that one dominant gene, Rfp, was required to achieve complete fertility restoration. As a first step toward cloning of this restorer gene, we attempted molecular mapping of the Rfp locus using the amplified fragment length polymorphism (AFLP) technique combined with bulked segregant analysis (BSA) method. A BC1 population segregating for Rfp gene was used for tagging. From the survey of 1,024 AFLP primer combinations, 13 linked AFLP markers were obtained and five of them were successfully converted into sequence characterized amplified region (SCAR) markers. A population of 193 plants was screened using these markers and the closest AFLP markers flanking Rfp were at the distances of 2.0 and 5.3 cM away, respectively. Further the AFLP or SCAR markers linked to the Rfp gene were integrated to one doubled-haploid (DH) population derived from the cross Quantum × No.2127-17 available in our laboratory, and Rfp gene was mapped on N18, which was the same as the previous report. These molecular markers will facilitate the marker-assisted selection (MAS) of pol CMS restorer lines.  相似文献   

5.
We have established marker-aided selection strategies for the two major Rf genes (Rf3 and Rf4) governing fertility restoration of␣cytoplasmic-genetic male sterility (CMS) in rice. Polymorphisms between restorer and non-restorer␣lines were observed using RG140/PvuII for Rf3 located on chromosome 1 and S10019/BstUI for Rf4 located on chromosome 10. DNA polymorphisms associated with these two loci in restorer lines of wild abortive (WA), Dissi, and Gambiaca cytoplasm are conserved, suggesting that similar biological processes control pollen fertility in this diverse cytoplasm. Because of their close linkage to Rf genes and distinct banding patterns, STS markers RG140/PvuII and S10019/BstUI are well suited for marker-aided selection, enhanced backcross procedures, and pyramiding of Rf genes in agronomically superior non-restorer lines. The combined use of markers associated with these two loci improved the efficiency of screening for putative restorer lines from a set of elite lines. Positional analyses of Rf4 and the inheritance pattern of the polymorphism in S10019/BstUI suggest that Rf4, governing fertility restoration in WA-CMS in rice, is likely to be the same gene governing fertility restoration in BT- and HL-CMS that has a gametophytic effect, which explains why 100% pollen fertility in hybrids is impossible to attain.  相似文献   

6.
The fertile pure line R3‐37 of common wheat with cytoplasm of Triticum timopheevii Zhuk. is an R‐line (restorer) that can restore the male fertility of A‐lines (male sterile lines) with T. timopheevii cytoplasm. In breeding hybrid wheat, the hybrid of the cross R3‐37/ Baimian3 was found to be completely male sterile, indicating that Baimian3 has some genes that are epistatic to the Rf genes in R3‐37. In order to elucidate the essence of this phenomenon, the male fertilities of the hybrids of 27 crosses including R3‐37 and/or Baimian3 were studied. The results show that inheritance of male fertility of the hybrid R3‐37/Baimian3 involves interactions among Rf alleles, male fertility‐inhibiting genes and genetic background. Although more than 70 different kinds of male sterile cytoplasm to common wheat have been discovered, the systems of hybrid wheat production based on male sterile cytoplasm are all the A‐line/R‐line type and all have similar problems of hybrid fertility restoration. This study confirmed that there is a new model (A‐line/R*‐line//R‐line) for producing hybrid wheat with high fertility restoration. In the new model, the completely male sterile hybrids of A‐line/R*‐line can act as common A‐line.  相似文献   

7.
Summary Identification and location of fertility restoring genes facilitates their deployment in a hybrid breeding program involving cytoplasmic male sterility (CMS) system. The study aimed to locate fertility restorer genes of CMSWA system on specific chromosomes of rice using primary trisomics of IR36 (restorer), CMS (IR58025A) and maintainer (IR58025B) lines. Primary trisomic series (Triplo 1 to 12) was crossed as maternal parent with the maintainer line IR58025B. The selected trisomic and disomic F1 plants were testcrossed as male parents with the CMS line IR58025A. Plants in testcross families derived from disomic F1 plants (Group I crosses) were all diploid; however, in the testcross families derived from trisomic F1 plants (Group II crosses), some trisomic plants were observed. Diploid plants in all testcross families were analyzed for pollen fertility using 1% IKI stain. All testeross families from Group I crosses segregated in the ratio of 2 fertile: 1 partially fertile+partially sterile: 1 sterile plants indicating that fertility restoration was controlled by two independent dominant genes: one of the genes was stronger than the other. Testcross families from Group II crosses segregated in 2 fertile: 1 partially fertile+ partially sterile: 1 sterile plants in crosses involving Triplo 1, 4, 5, 6, 8, 9, 11 and 12, but families involving triplo 7 and triplo 10 showed significantly higher X2 values, indicating that the two fertility restorer genes were located on chromosome 7 and 10. Stronger restorer gene (Rf-WA-1) was located on chromosome 7 and weaker restorer gene (Rf-WA-2) was located on chromosome 10. These findings should facilitate tagging of these genes with molecular markers with the ultimate aim to practice marker-aided selection for fertility restoration ability.  相似文献   

8.
X. L. Tan    Y. L. Tan    Y. H. Zhao    X. M. Zhang    R. K. Hong    S. L. Jin    X. R. Liu  D. J. Huang 《Plant Breeding》2004,123(4):338-341
Cytoplasmic male sterility of Dian‐type 1 (CMS‐D1) was developed 30 years ago in Yunnan. A major gene conferring fertility restoration for the CMS‐D1 system was detected by microsatellite markers in advanced inbred lines consisting of 196 maintainers and 62 restorers developed in breeding programmes of hybrid rice involving the CMS‐D1 system. The gene was mapped between two simple sequence repeat markers, OSR33 and RM228, on chromosome 10, and was temporarily designated as Rf‐D1(t). The genetic distances of the gene to the two microsatellite markers were 3.4 and 5.0 cM, respectively. This linkage was confirmed by using an F2 population derived from a cross between a CMS‐D1 line and a restorer. This study also demonstrated that using OSR33 was reliable and efficient for identification of restoring lines in hybrid rice breeding with the CMS‐D1 system.  相似文献   

9.
Stripe (yellow) rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating wheat diseases worldwide. Triticum aestivum-Haynaldia villosa 6VS/6AL translocation lines carrying the Yr26 gene on chromosome 1B, are resistant to most races of Pst used in virulence tests. In order to better utilize Yr26 for wheat improvement, we attempted to screen SSR and EST-based STS markers closely linked with Yr26. A total of 500 F2 plants and the F2:3 progenies derived from a cross between 92R137 and susceptible cultivar Yangmai 5 were inoculated with race CYR32. The analysis confirmed that stripe rust resistance was controlled by a single dominant gene, Yr26. Among 35 pairs of genomic SSR markers and 81 pairs of STS markers derived from EST sequences located on chromosome 1B, Yr26 was flanked by 5 SSR and 7 STS markers. The markers were mapped in deletion bins using CS aneuploid and deletion lines. The closest flanking marker loci, Xwe173 and Xbarc181, mapped in 1BL and the genetic distances from Yr26 were 1.4 cM and 6.7 cM, respectively. Some of these markers were previously reported on 1BS. Eight common wheat cultivars and lines developed from the T. aestivum-H. villosa 6VS/6AL translocation lines by different research groups were tested for presence of the markers. Five lines with Yr26 carried the flanking markers whereas three lines without Yr26 did not. The results indicated that the flanking markers should be useful in marker-assisted selection for incorporating Yr26 into wheat cultivars.  相似文献   

10.
分析与小麦抗旱性密切相关的水分胁迫应答蛋白, 定位蛋白基因并挖掘与其连锁的分子标记对小麦抗旱分子辅助选择具有重要意义。在一年两点田间全生育期抗旱性鉴定基础上, 以-0.5 MPa PEG-6000模拟干旱胁迫处理小麦幼苗48 h, 并应用SDS-PAGE方法检测分子量约66.2 kD的水分胁迫应答蛋白, 分析其表达与小麦抗旱性的关系。在128个小麦品种(系)中, 检测出67份表达该蛋白, 另61份未表达该蛋白; 前者的平均抗旱指数为1.00, 而后者为0.80, 有极显著差异(P<0.01), 且各抗旱性等级中表达该蛋白的品种比例随着抗性等级的降低而减小。利用晋麦47×西农2208杂交后代230个F3株系进行遗传分析, 发现该蛋白表达由1对显性基因控制; 目的基因与位于小麦5AS染色体上的5个SSR标记(Xgwm129、Xgwm304、Xbarc56、Xbarc117和Xbarc197)连锁, 位于邻近标记Xbarc56和Xbarc117之间, 遗传距离分别为2.2 cM和2.9 cM。用这两个紧密连锁标记检测128个小麦品种(系), 有67个品种(系)与晋麦47具有相同的标记位点, 其中86.6%的品种(系)(58/67)在水分胁迫后表达目标蛋白。该约66.2 kD的水分胁迫应答蛋白与小麦的抗旱性密切相关, 与其紧密连锁的分子标记可为小麦抗旱分子辅助选择提供依据。  相似文献   

11.
植物细胞质雄性不育育性恢复基因研究进展   总被引：1，自引：1，他引：0  
杂种优势已广泛应用于农业生产,这其中主要依靠细胞质雄性不育系统。细胞质雄性不育“三系”是杂交种选育的基础材料。其中,强恢复系的选育非常繁琐,且恢复力只能通过与不育系的测交来鉴定,既耗时又费力,因此,人们对育性恢复基因进行了大量的研究。本文归纳了恢复基因的结构特征、作用机理、遗传模式、基因定位及克隆上的研究进展和存在问题。认为随着二代测序技术的发展,可以利用全基因组重测序和转录组测序等技术开发新型分子标记进行恢复基因精细定位,或直接通过测序技术鉴定恢复基因。这将为恢复系的分子标记辅助选育和利用基因工程手段人工改良和创制恢复系提供帮助,也将为研究细胞质雄性不育育性恢复基因的遗传、进化和特征,全面解析植物细胞质雄性不育育性恢复机理奠定基础。  相似文献   

12.
B. Yue    B. A. Vick    X. Cai    J. Hu 《Plant Breeding》2010,129(1):24-28
The Rf1 gene in sunflower can effectively restore the pollen fertility of PET1 cytoplasm in male-sterile lines and has been widely used in commercial hybrid production. Identifying molecular markers tightly linked to this gene will be useful in marker-assisted selection to develop maintainer and restorer lines. Rf1 has been mapped to Linkage Group (LG) 13 of the public sunflower simple sequence repeat (SSR) map by aligning maps constructed from different populations and only one SSR marker was reported to be loosely linked to Rf1 . This paper reports the result of applying target region amplification polymorphism (TRAP) and SSR markers to map and develop a sequence-tagged site (STS) marker tightly linked to Rf1 using two populations derived from a cross between two U.S. public sunflower lines, RHA439 and cmsHA441. An SSR marker, ORS511, was 3.7 cM from the Rf1 gene and a TRAP marker, K11F05Sa12-160, was linked to Rf1 at a distance of 0.4 cM. This TRAP marker was converted to an STS marker for using in sunflower breeding.  相似文献   

13.
Fertility restoration by dominant nuclear genes is essential for hybrid breeding based on cytoplasmic male sterility (CMS) to obtain heterotic effects and high seed yields. In sunflower, only the PET1 sterility inducing cytoplasm has been used in commercial hybrid breeding until now. This particular male sterility was derived from an interspecific hybrid Helianthus petiolaris × H. annuus. For the recent work we used the segregating population RHA325(CMS) × HA342, based on the PET1 cytoplasm. Molecular markers were mapped within 1.1 cM around the restoration locus Rf1. At the distal side, the marker OP-K13_454 mapped at a distance of 0.9 cM and E32M36-155R at 0.7 cM from Rf1. At the proximal side the markers E44M70-275A, E42M76-125A and E33M61-136R were mapped at 0.1, 0.2, and 0.3 cM from the restorer locus, respectively. These markers provide an excellent basis for a map based cloning approach and for marker-assisted sunflower breeding.  相似文献   

14.
Leaf rust caused by the fungus Puccinia triticina is one of the most important diseases of wheat (Triticum aestivum) worldwide. The use of resistant wheat cultivars is considered the most economical and environment-friendly approach in controlling the disease. The Lr38 gene, introgressed from Agropyron intermedium, confers a stable seedling and adult plant resistance against multiple isolates tested in Europe. In the present study, 94 F2 plants resulting from a cross made between the resistant Thatcher-derived near-isogenic line (NIL) RL6097, and the susceptible Ethiopian wheat cultivar Kubsa were used to map the Thatcher Lr38 locus in wheat using simple sequence repeat (SSR) markers. Out of 54 markers tested, 15 SSRs were polymorphic between the two parents and subsequently genotyped in the population. The P. triticina isolate DZ7-24 (race FGJTJ), discriminating Lr38 resistant and susceptible plants, was used to inoculate seedlings of the two parents and the segregating population. The SSR markers Xwmc773 and Xbarc273 flanked the Lr38 locus at a distance of 6.1 and 7.9 cM, respectively, to the proximal end of wheat chromosome arm 6DL. The SSR markers Xcfd5 and Xcfd60 both flanked the locus at a distance of 22.1 cM to the distal end of 6DL. In future, these SSR markers can be used by wheat breeders and pathologists for marker assisted selection (MAS) of Lr38-mediated leaf rust resistance in wheat.  相似文献   

15.
Tagging of restorer genes for wild abortive (WA) CMS source by studying a 222 individual plants from a F2 population of a cross between IR58025A × IR42686R. The restorer line IR42686R that was used in this study had been previously derived through random mating composite population (RMCP) involving 12 parents facilitated by IR36 genetic male sterility. Four Rf genes were tagged to simple sequence repeats (SSR) markers on chromosomes 1, 7, 10, 12 by recessive class analysis. The recombination frequency between a positive marker and Rf locus was calculated using maximum likelihood estimator assuming that all the 46 extremely sterile individual plants were homozygous at the targeted Rf locus. The recombination frequency between the marker and the restorer trait were converted to genetic distances using Kosambi function. A new Rf locus designated as Rf7 on chromosome 12 was found to be linked to RM7003 at a genetic distance of 13.3 cM (LOD 6.12). We report here first, a new molecular marker (RM 6344) linked to Rf4 locus on chromosome 7 that was previously mapped by trisomic analysis. RM443 and RM315 were flanking the Rf3 gene at a genetic distance of 4.4 (LOD 10.29) and 20.7 cM (LOD 3.98) on chromosome 1, respectively. The Rf6 was flanked on both side with SSR markers RM258 and RM591 at a genetic distance of 4.4 (LOD 10.29) and 23.3 cM (LOD 3.39) located on chromosome 10. The random mating composite population is an excellent breeding approach to develop superior restorer lines and for pyramiding different Rf genes of different CMS systems. Rf genes tagged with closely linked SSR markers would be facilitating marker assisted selection (MAS) in hybrid rice breeding program by reducing time and workload for identifying potential restorers. L. Bazrkar and A. J. Ali equally contributed to this work.  相似文献   

16.
Previously, novel cytoplasmic male-sterility (CMS) caused by DCGMS cytoplasm was discovered in radish (Raphanus sativus L.) introduced from Uzbekistan. We performed extensive progeny tests and identified two fertility restorer lines (‘R171’ and ‘R121’) for this new CMS. Two F1 hybrid populations were self-pollinated and backcrossed to produce F2 and BC populations. Inheritance patterns of male-sterility in segregating populations varied depending on paternal lines. Segregation of male-sterility in F2 populations originating from the cross between MS19 and R121 showed that a single locus was involved in fertility restoration. However, populations originating from the cross between MS15 and R171 showed the involvement of more than one restorer-of-fertility genes. The single fertility restorer locus identified in the cross between MS19 and R121 was designated Rfd1 locus. Bulked segregant analysis was performed using RAPD and AFLP, which identified one marker each. Both RAPD and AFLP markers were converted into simple PCR-based co-dominant markers after their isolated flanking sequences were analyzed. Indels 773-bp and 67-bp in length were identified between two Rfd1 allele-linked flanking sequences of the RAPD and AFLP fragments, respectively, then utilized to develop simple PCR markers. In addition, we prove that the newly identified Rfd1 locus is independent of the Rfo locus, another radish fertility restorer for CMS caused by Ogura cytoplasm.  相似文献   

17.
棉花细胞质雄性不育系统在实现棉花杂交种子大规模生产和培育高产、优质、抗逆等棉花新品种中具有重要的应用价值,而恢复系的好坏对细胞质雄性不育系杂交种的选育的利用起着举足轻重的作用。因此,培育优良恢复系至关重要。主要介绍了棉花细胞质雄性不育系、恢复系的类型,综述了棉花细胞质雄性不育育性恢复基因的遗传方式和遗传定位研究进展,讨论了恢复基因的精细定位和分子标记鉴定在分子标记辅助育种中的意义和应用前景,并针对目前存在的问题提出相应对策。  相似文献   

18.
The genetic relationship among three cytoplasmic male sterility (CMS) systems, consisting of WA, Dissi, and Gambiaca, was studied. The results showed that the maintainers of one CMS system can also maintain sterility in other cytoplasmic backgrounds. The F1 plants derived from crosses involving A and R lines of the respective cytoplasm and their cross-combination with other CMS systems showed similar pollen and spikelet fertility values, indicating that similar biological processes govern fertility restoration in these three CMS systems. The results from an inheritance study showed that the pollen fertility restoration in all three CMS systems was governed by two independent and dominant genes with classical duplicate gene action. Three F2 populations, generated from the crosses between the parents of good-performing rice hybrids, that possess WA, Dissi, and Gambiaca CMS cytoplasm, were used to map the Rf genes. For the WA-CMS system, Rf3 was located at a distance of 2.8 cM from RM490 on chromosome 1 and Rf4 was located at 1.6 cM from RM1108 on chromosome 10. For the Dissi-CMS system, Rf3 was located on chromosome 1 at 1.9 cM from RM7466 and Rf4 on chromosome 10 was located at 2.3 cM from RM6100. The effect of Rf3 on pollen fertility appeared to be stronger than the effect of Rf4. In the Gambiaca-CMS system, only one major locus was mapped on chromosome 1 at 2.1 cM from RM576. These studies have led to the development of marker-assisted selection (MAS) for selecting putative restorer lines, new approaches to alloplasmic line breeding, and the transfer of Rf genes into adapted cultivars through a backcrossing program in an active hybrid rice breeding program.  相似文献   

19.
A partial genetic linkage map was constructed on 71 doubled-haploid lines derived from a cross between the barley lines Tadmor and WI2291 with 181 molecular markers. The segregating population was used to detect markers linked to the gene Mlg conferring resistance to powdery mildew (Erysiphe graminis f. sp. hordei) and to genes for quantitative resistance to scald (Rhynchosporium secalis). The gene Mlg on chromosome 4H was flanked by two AFLP markers at a distance of 2.0 and 2.4 cM, respectively. QTLs for resistance to scald were detected on chromosomes 2H and 3H. This association of molecular markers with qualitative and quantitative disease resistance loci represents a valuable starting-point for marker-assisted selection. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
The photoperiod/temperature-sensitive genic male sterile (P/TGMS) character is important for use of heterosis in hybrid wheat. In the present study, the fertility of 172 doubled haploid (DH) lines derived from the cross between a P/TGMS wheat line BS366 and a restorer wheat line Baiyu149 was investigated under both fertile and sterile environments during three cropping seasons. The phenotype was recorded based on the international seed setting rate. A total of 167 SSR and 1,278 SNP markers were used to construct a linkage map, with a total length of 3,748.94 cM and an average marker interval of 2.59 cM. Three QTLs were identified and designated as QF.bhw-2DS, QF.bhw-4BS and QF.bhw-7Al, explaining 6.9%–12.8%, 19.7%–25.6% and 7.2%–8.8% of the phenotypic variances, respectively. These results lay a good basis for application of male sterility-related molecular markers in improvement of two-line hybrid wheat breeding system.  相似文献   

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