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Molecular mapping of a fertility restorer gene for Owen cytoplasmic male sterility in sugar beet 总被引:2,自引:0,他引:2
Hagihara E Itchoda N Habu Y Iida S Mikami T Kubo T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(2):250-255
We report here the molecular mapping of a fertility restorer gene (named Rf1) for Owen cytoplasmic male sterility in sugar beet. Eight AFLP and two RAPD markers, tightly linked to the Rf1 locus, were identified using bulked segregant analysis. Three AFLP markers, mAFEM972, mAFEM976 and mAFEM985, were found to co-segregate with the Rf1 allele in our mapping populations. With the help of RFLP markers, previously mapped on the sugar beet genome, we showed that Rf1 is positioned in the terminal region of linkage group Kiel III/Koeln IV. This map location agrees well with that found for the restorer gene X, which suggests that the Rf1 locus corresponds to the X locus. The availability of the molecular markers will facilitate the selection of maintainer–pollinator lines in breeding program and provide the foundation for map-based cloning of the Rf1 gene. 相似文献
3.
Inheritance and fine mapping of fertility restoration for cytoplasmic male sterility in Gossypium hirsutum L 总被引:19,自引:0,他引:19
Liu L Guo W Zhu X Zhang T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,106(3):461-469
Genetics of CMS fertility restoration was presented through the analysis of classic genetics and molecular markers. Based on F(2) segregation of the crosses between CMS and the restoring lines, the testcrosses and F(1) x F(1) populations, together with RAPD and SSR mapping, one dominant gene was identified to control the CMS fertility restoration in cotton. The strategy of genotype representation analysis (GRA) was put forward to screen the markers linked with the Rf(1) locus. Using 1,025 random decamer primers and 282 pairs of SSR primers, two RAPD and three SSR markers were identified to be closely linked to the Rf(1) gene. Among the five markers, three were co-dominantly inherited. Additionally, based on the analysis of monosomic and telesomic lines with one SSR maker, the Rf(1) locus could be located on the long arm of chromosome 4. The molecular markers available here are helpful in the development of the elite restoring lines in cotton by marker-assisted selection. 相似文献
4.
T. L. Kamps C. D. Chase 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):525-531
Cytoplasmic male sterility (CMS) is the maternally inherited inability to produce functional pollen. The Rf3 allele of the nuclear gene rf3 gametophytically restores male fertility to maize plants with the S-type of CMS. The rf3 locus is on the long arm of maize chromosome two (2L). Using 2L RFLPs and three-point mapping analysis we showed that the
rf3 locus is located an estimated 4.3 cM distal to the whp locus and 6.4 cM proximal to the bnl17.14 locus. This information was used in combination with RFLPs on two additional maize chromosomes to show that Rf3/rf3 CMS-S plants may aberrantly transmit the nonrestoring allele, rf3, through the male gametophyte.
Received: 30 September 1996/Accepted: 21 March 1997 相似文献
5.
J. Cai Z. J. Dai H. T. Zhu R. Z. Zeng Z. M. Zhang T. -F. Ma G. -Q. Zhang 《Biologia Plantarum》2014,58(2):241-246
Rice chromosome single segment substitution line (SSSL) W23-19-06-06-11 with the genotype Rf3Rf3/Rf4Rf4, a strong restorer line for wild-abortive (WA) cytoplasmic male sterility (CMS), was recently identified from the SSSL library. To investigate the genetic mode of Rf genes and the genetic relationship among WA, yegong (Y), and dwarf-wildabortive (DA) CMS systems, the plants derived from three BC3F2 populations involving W23-19-06-06-11 and the three CMS lines, that carried the Rf3Rf3/Rf4Rf4, Rf3Rf3/rf4rf4, and rf3rf3/Rf4Rf4 genotypes and WA-, Y-, and DA-CMS cytoplasm, were selected and their pollen and spikelet fertility were evaluated. The results show that the genetic effect displayed a trend of Y-CMS > WA-CMS > DA-CMS in the genetic background of W23-19-06-06-11, the effect of Rf4 appeared to be slightly larger than that of Rf3, and their effects were additive for the three CMS systems. Two pairs of dominant genes governed the fertility restoration in pollen and spikelet in the W23-19-06-06-11 which indicates that the genetic mode of the Rf genes was a qualitative character for the three CMS systems. 相似文献
6.
J. Cai Q. P. Liao Z. J. Dai H. T. Zhu R. Z. Zeng Z. M. Zhang G. -Q. Zhang 《Biologia Plantarum》2013,57(2):274-280
To reveal the allelic differentiations at the two genes for fertility restoration (Rf) on chromosomes 1 (Rf3) and 10 (Rf4), 15 chromosome single segment substitution lines (SSSLs) with the Rf3 locus and 18 SSSLs with the Rf4 locus were crossed with Bobai A (BbA), a cytoplasmic male sterility line with wild abortive type of cytoplasm (WA-CMS), respectively. Based on the pollen and seed fertility of the F1 hybrids, the Rf3 and Rf4 genes were each classified into four alleles, namely Rf3-1, Rf3-2, Rf3-3, and Rf3-4 for Rf3, and Rf4-1, Rf4-2, Rf4-3, and Rf4-4 for Rf4. Out of the 33 SSSLs, an SSSL W23-19-06-06-11 carrying the genotype Rf3-4Rf3-4/Rf4-4Rf4-4 possessed the strongest restoring ability for BbA. To determine the genetic effects of Rf3 and Rf4 for WA-CMS, one BC3F2 population possessing the genetic background of W23-19-06-06-11 was generated from the cross between W23-19-06-06-11 and BbA by backcrossing and marker-assisted selection. In the BC3F2 population, the plants carrying the Rf3Rf3/Rf4Rf4, Rf3Rf3/rf4rf4, and rf3rf3/Rf4Rf4 genotypes were selected and their phenotyping for pollen and spikelet fertility were evaluated. The result showed that under the genetic background of SSSL W23-19-06-06-11, the effect of Rf4 appeared to be slightly larger than that of Rf3 and their effects were additive for WA-CMS system. These studies will lead to the transfer of Rf genes into adapted cultivars through marker-assisted selection in active hybrid rice breeding programs. 相似文献
7.
Arun Kumar Singh Revathi Ponnuswamy M. Srinivas Prasad R. M. Sundaram A. S. Hari Prasad P. Senguttuvel K. B. Kempa Raju K. Sruthi 《Physiology and Molecular Biology of Plants》2023,29(2):253
Hybrid rice technology offers great promise to further enhance rice production and productivity for global food security. Improving hybrid rice parental lines is the first step in developing heterotic rice hybrids. To improve resistance against blast disease, a maintainer line DRR 9B was fortified with a major broad-spectrum blast resistance gene Pi2 through marker-assisted selection. The rice blast caused by Magnaporthe oryzae is a major disease and can cause severe yield losses upto 100%. The NILs of Samba Mahsuri namely BA-23-11-89-12-168 possessing Pi2 was utilized as a donor parent. The PCR-based molecular marker tightly linked to Pi2 gene was used for the foreground selection at BC1F1 generation. The molecular marker tightly linked to the major fertility restorer gene Rf4 was used for negative selection (i.e., selection of plants possessing non fertility restoring alleles) at BC1F1 generation to identify maintainer lines. The positive plants with Rf4 gene were added to the restorer pool for restorer line development. At each stage, MAS for Pi2 coupled with stringent phenotypic selection for agro-morphological and grain quality traits were exercised. At BC1F3 generation, one hundred families were screened against blast disease at uniform blast nursery (UBN) and selected resistant lines were advanced to next generations. In the BC1F5 generation plants were subjected to agro-morphological evaluation for yield and yield-contributing traits. The selected plants at BC1F5 generation were crossed with DRR 9A to assess the maintainer ability of blast resistance lines and for further CMS line conversion for hybrid rice breeding for developing blast resistance rice hybrids. 相似文献
8.
Genetics of fertility restoration in the C-group of cytoplasmic male sterility in maize 总被引:5,自引:0,他引:5
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The genetics of fertility restoration of cms-C group cytoplasm of maize was studied using crosses involving stable maintainer lines and lines that restored full pollen fertility. Pollen fertility in the sources of cms-C sterile cytoplasms studied was restored by a single dominant restorer (Rf4) gene. The fertility restoration was sporophytic. Allelism tests among five restorer lines showed that they all apparently carried the same alleles (Rf4 Rf4). Similar tests also demonstrated that seven nonrestoring maintainer lines had apparently the same genotype (rf4 rf4), although a partial "late break" of fertility was observed at low levels in some maintainer crosses. Comparative studies among different cms-C sources (C, Bb, ES, PR and RB) indicated that similar inheritance of fertility restoration was involved. The data indicated that a single, dominant Rf gene is involved in the restoration of several C-group cytoplasms, at least in the lines studied here. This is the first single-gene, sporophytic restorer system described in maize to date. 相似文献
9.
Jiao-Jiao Ji Wei Huang Yan-Xu Yin Zheng Li Zhen-Hui Gong 《Molecular breeding : new strategies in plant improvement》2014,33(3):679-690
Molecular markers, coxII SCAR, atp6-2 SCAR and accD-U, have been used for marker-assisted selection of cytoplasmic male sterility (CMS) in pepper. However, the presence of these markers at the sub-stoichiometric level in maintainer lines affects the reliable selection of male sterile (S-) cytoplasm. This study aimed to develop a new CMS-specific molecular marker, SCAR130, for reliable identification of S-cytoplasm in pepper, while the new and three previous molecular markers were used to determine the cytoplasm types of pepper lines. Based on mitochondrial genome sequence related amplified polymorphism (SRAP) analysis of the CMS lines and the maintainer lines, SCAR130 was developed from a 10-bp deletion at the SRAP primer binding site in the CMS line (130 bp) compared with that in the maintainer line (140 bp). S-cytoplasm could be unambiguously selected from the pepper lines by the different length of the marker bands. Application of the four molecular markers to various pepper lines revealed that SCAR130 is more reliable than the other three previous markers, orf507, ψatp6-2 and accD-U. Homology alignment with BLAST showed that the marker was located between trnE and trnS in the Nicotiana tabacum mitochondrial genome. Furthermore, expression of the marker-linked gene was significantly higher at the pollen abortive stage in the CMS line (HW203A) than in the maintainer line, which indicated that the marker was closely related to male sterility. Hence, factors other than orf507 and ψatp6-2 may exist for the regulation of male sterility in pepper. 相似文献
10.
Horn R Kusterer B Lazarescu E Prüfe M Friedt W 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,106(4):599-606
Up to now a single cytoplasmic male sterility (CMS) source, PET1, is used worldwide for hybrid breeding in sunflower. Introgression of the restorer gene Rf1, responsible for fertility restoration, into new breeding material requires tightly linked markers to perform an efficient marker-assisted selection. A survey of 520 decamer primers by bulked segregant analyses identified five RAPD markers linked to the restorer gene Rf1. In a F(2) population of 183 individuals one of the RAPD markers, OPK13_454, mapped 0.8 cM from Rf1, followed by OPY10_740 with 2 cM. Bulked segregant analyses using 48 AFLP primer combinations identified 17 polymorphisms, which could be mapped in the same linkage group as Rf1. E33M61_136, and E41M48_113 were mapped 0.3 cM and 1.6 cM from the gene, respectively. Conversion of E41M48_113 into a sequence-specific marker resulted in a monomorphic pattern. However, two of the RAPD markers, OPK13_454 and OPY10_740, were successfully converted into SCAR markers, HRG01 and HRG02, which are now available for marker-assisted selection. To investigate the utility of these SCAR markers in other cross-combinations they were tested in a set of 20 lines. Comparison of the patterns of 11 restorer and nine maintainer lines of PET1 demonstrated that the markers OPK13_454/HRG01 and HRG02 were absent in all maintainer lines but present in all restorer lines, apart from the high oleic line RHA348 and the dwarf line Gio55. In addition, restorer lines developed from the interspecific hybrids Helianthus annuus x Helianthus mollis and H. annuus x Helianthus rigidus gave the same characteristic amplification products. 相似文献
11.
Hagihara E Matsuhira H Ueda M Mikami T Kubo T 《Molecular genetics and genomics : MGG》2005,274(3):316-323
Rf1 is a nuclear gene that controls fertility restoration in cases of cytoplasmic male sterility caused by the Owen cytoplasm
in sugar beet. In order to isolate the gene by positional cloning, a BAC library was constructed from a restorer line, NK198,
with the genotype Rf1Rf1. The library contained 32,180 clones with an average insert size of 97.8 kb, providing 3.4 genome equivalents. Five AFLP
markers closely linked to Rf1 were used to screen the library. As a result, we identified eight different BAC clones that were clustered into two contigs.
The gap between the two contigs was filled by chromosome walking. To map the Rf1 region in more detail, we developed five cleaved amplified polymorphic sequence (CAPS) markers from the BAC DNAs identified,
and carried out genotyping of 509 plants in the mapping population with the Rf1-flanking AFLP and CAPS markers. Thirteen plants in which recombination events had occurred in the vicinity of the Rf1 locus were identified and used to map the molecular markers relative to each other and to Rf1. In this way, we were able to restrict the possible location of the Rf1 gene to a minimum of six BAC clones spanning an interval of approximately 250 kb.
The first two authors contributed equally to this work. 相似文献
12.
Linkage analysis between the partial restoration (pr) and the restorer-of-fertility (Rf) loci in pepper cytoplasmic male sterility 总被引:1,自引:0,他引:1
Lee J Yoon JB Park HG 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,117(3):383-389
Cytoplasmic male sterility (CMS) in chili pepper is restored by one major dominant nuclear gene, restorer-of-fertility (Rf), together with some modifier genes and is also affected by temperature. As a result, male fertility was identified as having several phenotypes. That identified and used in the present study allowed partial restoration of fertility, producing plants that simultaneously produce normal and aborted pollen grains, with most grains stuck to the anther wall, even after dehiscence, resulting in low seed set per fruit. The trait was visible only in the presence of Paterson's sterile cytoplasm and was controlled by a recessive nuclear gene, partial restoration (pr). A CAPS marker, PR-CAPS, closely linked to the trait, has been developed by Lee et al. (2008). In this study, linkage analysis was performed in 205 F(2) individuals derived from the 'Buja' Korean commercial F(1) chili pepper variety using the PR-CAPS marker and the three Rf-linked markers (OPP13-CAPS, AFRF8-CAPS, and CRF-SCAR) previously reported. Consequently, we found that these four markers were tightly linked. This result means that the pr gene might be tightly linked to the Rf locus or the third allele of Rf locus. The sequence diversity of the pr- and Rf-linked markers was also analyzed. The internal sequences of OPP13-CAPS (1,180 bp) and PR-CAPS (640 bp) markers in 91 Korean inbred lines were clearly divided into three haplotypes. According to the sequencing results, a new PR-CAPS (MseI or SphI digestion) marker was designed to distinguish the three haplotypes. This marker will be useful for marker-assisted selection to develop new maintainers and restorers in commercial hybrid pepper breeding using CMS. 相似文献
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14.
Background
Soybean cyst nematode (SCN) is the most economically devastating pathogen of soybean. Two resistance loci, Rhg1 and Rhg4 primarily contribute resistance to SCN race 3 in soybean. Peking and PI 88788 are the two major sources of SCN resistance with Peking requiring both Rhg1 and Rhg4 alleles and PI 88788 only the Rhg1 allele. Although simple sequence repeat (SSR) markers have been reported for both loci, they are linked markers and limited to be applied in breeding programs due to accuracy, throughput and cost of detection methods. The objectives of this study were to develop robust functional marker assays for high-throughput selection of SCN resistance and to differentiate the sources of resistance.Results
Based on the genomic DNA sequences of 27 soybean lines with known SCN phenotypes, we have developed Kompetitive Allele Specific PCR (KASP) assays for two Single nucleotide polymorphisms (SNPs) from Glyma08g11490 for the selection of the Rhg4 resistance allele. Moreover, the genomic DNA of Glyma18g02590 at the Rhg1 locus from 11 soybean lines and cDNA of Forrest, Essex, Williams 82 and PI 88788 were fully sequenced. Pairwise sequence alignment revealed seven SNPs/insertion/deletions (InDels), five in the 6th exon and two in the last exon. Using the same 27 soybean lines, we identified one SNP that can be used to select the Rhg1 resistance allele and another SNP that can be employed to differentiate Peking and PI 88788-type resistance. These SNP markers have been validated and a strong correlation was observed between the SNP genotypes and reactions to SCN race 3 using a panel of 153 soybean lines, as well as a bi-parental population, F5–derived recombinant inbred lines (RILs) from G00-3213 x LG04-6000.Conclusions
Three functional SNP markers (two for Rhg1 locus and one for Rhg4 locus) were identified that could provide genotype information for the selection of SCN resistance and differentiate Peking from PI 88788 source for most germplasm lines. The robust KASP SNP marker assays were developed. In most contexts, use of one or two of these markers is sufficient for high-throughput marker-assisted selection of plants that will exhibit SCN resistance.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1531-3) contains supplementary material, which is available to authorized users. 相似文献15.
Molecular markers developed from the flanking sequences of two cytoplasmic male sterility (CMS)-associated genes, orf456 and ψatp6-2, have been used for marker-assisted selection of CMS in pepper. However, in practice, the presence of orf456 and ψatp6-2 at substoichiometric levels even in maintainer lines hampers reliable selection of plants containing the CMS gene. In this
study, we developed a novel CMS-specific molecular marker, accD-U, for reliable determination of CMS lines in pepper, and
used the newly and previously developed markers to determine the cytoplasm types of pepper breeding lines and germplasms.
This marker was developed from a deletion in a chloroplast-derived sequence in the mitochondrial genome of a CMS pepper line.
CMS pepper lines could be unambiguously determined by presence or absence of the accD-U marker band. Application of orf456, ψatp6-2 and accD-U to various pepper breeding lines and germplasms revealed that accD-U is the most reliable CMS selection marker.
A wide distribution of orf456, but not ψatp6-2, in germplasms suggests that the pepper cytoplasm containing both orf456 and ψatp6-2 has been selected as CMS cytoplasm from cytoplasm containing only orf456. Furthermore, factors other than orf456 may be required for the regulation of male sterility in pepper. 相似文献
16.
Shuangping Heng Chao Wei Bing Jing Zhengjie Wan Jing Wen Bin Yi Chaozhi Ma Jinxing Tu Tingdong Fu Jinxiong Shen 《BMC genomics》2014,15(1)
Background
Cytoplasmic male sterility (CMS) is not only important for exploiting heterosis in crop plants, but also as a model for investigating nuclear-cytoplasmic interaction. CMS may be caused by mutations, rearrangement or recombination in the mitochondrial genome. Understanding the mitochondrial genome is often the first and key step in unraveling the molecular and genetic basis of CMS in plants. Comparative analysis of the mitochondrial genome of the hau CMS line and its maintainer line in B. juneca (Brassica juncea) may help show the origin of the CMS-associated gene orf288.Results
Through next-generation sequencing, the B. juncea hau CMS mitochondrial genome was assembled into a single, circular-mapping molecule that is 247,903 bp in size and 45.08% in GC content. In addition to the CMS associated gene orf288, the genome contains 35 protein-encoding genes, 3 rRNAs, 25 tRNA genes and 29 ORFs of unknown function. The mitochondrial genome sizes of the maintainer line and another normal type line “J163-4” are both 219,863 bp and with GC content at 45.23%. The maintainer line has 36 genes with protein products, 3 rRNAs, 22 tRNA genes and 31 unidentified ORFs. Comparative analysis the mitochondrial genomes of the hau CMS line and its maintainer line allowed us to develop specific markers to separate the two lines at the seedling stage. We also confirmed that different mitotypes coexist substoichiometrically in hau CMS lines and its maintainer lines in B. juncea. The number of repeats larger than 100 bp in the hau CMS line (16 repeats) are nearly twice of those found in the maintainer line (9 repeats). Phylogenetic analysis of the CMS-associated gene orf288 and four other homologous sequences in Brassicaceae show that orf288 was clearly different from orf263 in Brassica tournefortii despite of strong similarity.Conclusion
The hau CMS mitochondrial genome was highly rearranged when compared with its iso-nuclear maintainer line mitochondrial genome. This study may be useful for studying the mechanism of natural CMS in B. juncea, performing comparative analysis on sequenced mitochondrial genomes in Brassicas, and uncovering the origin of the hau CMS mitotype and structural and evolutionary differences between different mitotypes.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-322) contains supplementary material, which is available to authorized users. 相似文献17.
AFLP and PCR-based markers linked to Rf3, a fertility restorer gene for S cytoplasmic male sterility in maize 总被引:2,自引:0,他引:2
The Rf3 gene restores the pollen fertility disturbed by S male sterile cytoplasm. In order to develop molecular markers tightly linked to Rf3, we used amplified fragment length polymorphism (AFLP) technique with near isogenic lines (NILs) and bulk segregant analysis (BSA). A BC1F1 population from a pair of NILs with different Rf3 locus was constructed and 528 primer combinations was screened. A linkage map was constructed around the Rf3 locus, which was mapped on the distal region of chromosome 2 long arm with the help of SSR marker UMC2184. The closest marker E7P6 was 0.9 cM away from Rf3. Marker E3P1, 2.4 cM from Rf3, and E12M7, 1.8 cM from Rf3, were converted into a codominant CAPS and a dominant SCAR marker, and designated as CAPSE3P1 and SCARE12M7, respectively. These markers are useful for marker-assisted selection and map-based cloning of the Rf3 gene. 相似文献
18.
K. Pranathi B. C. Viraktamath C. N. Neeraja S. M. Balachandran A. S. Hari prasad P. Koteswara Rao P. Revathi P. Senguttuvel S. K. Hajira C. H. Balachiranjeevi S. Bhaskar Naik V. Abhilash M. Praveen K. Parimala S. R. Kulkarni M. Anila G. Rekha M. B. V. N. Koushik B. Kemparaju M. S. Madhav S. K. Mangrauthia G. Harika T. Dilip R. R. Kale V. Vishnu Prasanth V. Ravindra Babu R. M. Sundaram 《Molecular breeding : new strategies in plant improvement》2016,36(10):145
Two major nuclear genes, Rf3 and Rf4, are known to be associated with fertility restoration of wild-abortive cytoplasmic male sterility (WA-CMS) in rice. In the present study, through a comparative sequence analysis of the reported putative candidate genes, viz. PPR9-782-(M,I) and PPR762 (for Rf4) and SF21 (for Rf3), among restorer and maintainer lines of rice, we identified significant polymorphism between the two lines and developed a set of PCR-based codominant markers, which could distinguish maintainers from restorers. Among the five markers developed targeting the polymorphisms in PPR9-782-(M,I), the marker RMS-PPR9-1 was observed to show clear polymorphism between the restorer (n = 120) and maintainer lines (n = 44) analyzed. Another codominant marker, named RMS-PPR762 targeting PPR762, displayed a lower efficiency in identification of restorers and maintainers, indicating that PPR9-782-(M,I) is indeed the candidate gene for Rf4. With respect to Rf3, a codominant marker, named RMS-SF21-5 developed targeting SF21, displayed significantly lower efficiency in identification of restorers and non-restorers as compared to the Rf4-specific markers. Validation of these markers in a F2 mapping population segregating for fertility restoration indicated that Rf4 has a major influence on fertility restoration and Rf3 is a minor gene. Further, the functional marker RMS-PPR9-1 was observed to be very useful in identification of impurities in a seed lot of the popular hybrid, DRRH3. Interestingly, when RMS-PPR9-1 and RMS-SF21-5 were considered in conjunction with analysis, near-complete, marker–trait co-segregation was observed, indicating that deployment of the candidate gene-specific markers both Rf4 and Rf3, together, can be helpful in accurate identification of fertility restorer lines and can facilitate targeted transfer of the two restorer genes into elite varieties through marker-assisted breeding. 相似文献
19.
Kenta Shirasawa Takuma Sekii Yoshinori Ogihara Teppei Yamada Sachiko Shirasawa Sachie Kishitani Kunihiko Sasaki Minoru Nishimura Kuniaki Nagano Takeshi Nishio 《Molecular breeding : new strategies in plant improvement》2013,32(1):223-232
An unusually high temperature during the grain-filling period, such as that caused by global warming, impairs the quality of rice (Oryza sativa L.) grains. This sensitivity to high-temperature stress is different among cultivars, suggesting the possibility of developing a high-temperature-tolerant cultivar. Since marker-assisted selection would reduce time and labor in breeding for such a quantitative trait, we determined the chromosomal region responsible for high-temperature tolerance during the grain-filling period. A high-temperature-sensitive japonica cultivar Tohoku 168 and a tolerant japonica cultivar Kokoromachi were selected as the parental lines of recombinant inbred lines (RILs) by high-temperature stress treatment from 5 to 10 days after anthesis, which was found to be the period most critical for grain quality. Using the RILs, whose genotypes were determined by analysis with 131 DNA markers which were selected as polymorphic markers between these two cultivars from 2,648 DNA markers tested, the quantitative trait locus (QTL) for the percentage of white-back grains was mapped on chromosome 6. The Kokoromachi allele of the QTL, which had a positive additive effect on the high-temperature tolerance, was introduced into the Tohoku 168 genome by repeated backcrossings with marker-assisted selection. Using high-temperature stress treatment of the near isogenic lines developed, the QTL on chromosome 6 was localized within a 1.9-Mb region between two DNA markers, ktIndel001 and RFT1. These DNA markers would be useful not only for breeding high-temperature-tolerant cultivars but also for map-based cloning of the QTL. 相似文献
20.
Khalid Meksem Dario Leister Johan Peleman Marc Zabeau Francesco Salamini Christiane Gebhardt 《Molecular genetics and genomics : MGG》1995,249(1):74-81
The R1 allele confers on potato a race-specific resistance to Phytophthora infestans. The corresponding genetic locus maps on chromosome V in a region in which several other resistance genes are also located. As part of a strategy for cloning R1, a high-resolution genetic map was constructed for the segment of chromosome V that is bordered by the RFLP loci GP21 and GP179 and includes the R1 locus. Bulked segregant analysis and markers based on amplified fragment length polymorphisms (AFLP markers) were used to select molecular markers closely linked to R1. Twenty-nine of approximately 3200 informative AFLP loci displayed linkage to the R1 locus. Based on the genotypic analysis of 461 gametes, eight loci mapped within the GP21–GP179 interval. Two of those could not be seperated from R1 by recombination. For genotyping large numbers of plants with respect to the flanking markers GP21 and GP179 PCR based assays were also developed which allowed marker-assisted selection of plants with genotypes Rr and rr and of recombinant plants. 相似文献