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Li C, Shi H, Xu L, Xing M, Wu X, Bai Y, Niu M, Gao J, Zhou Q, Cui C. Combining transcriptomics and metabolomics to identify key response genes for aluminum toxicity in the root system of Brassica napus L. seedlings. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2023; 136:169. [PMID: 37418156 PMCID: PMC10328865 DOI: 10.1007/s00122-023-04412-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 06/22/2023] [Indexed: 07/08/2023]
Abstract
By integrating QTL mapping, transcriptomics and metabolomics, 138 hub genes were identified in rapeseed root response to aluminum stress and mainly involved in metabolism of lipids, carbohydrates and secondary metabolites. Aluminum (Al) toxicity has become one of the important abiotic stress factors in areas with acid soil, which hinders the absorption of water and nutrients by roots, and consequently retards the growth of crops. A deeper understanding of the stress-response mechanism of Brassica napus may allow us to identify the tolerance gene(s) and use this information in breeding-resistant crop varieties. In this study, a population of 138 recombinant inbred lines (RILs) was subjected to aluminum stress, and QTL (quantitative trait locus) mapping was used to preliminarily locate quantitative trait loci related to aluminum stress. Root tissues from seedlings of an aluminum-resistant (R) line and an aluminum-sensitive (S) line from the RIL population were harvested for transcriptome sequencing and metabolome determination. By combining the data on quantitative trait genes (QTGs), differentially expressed genes (DEGs), and differentially accumulated metabolites (DAMs), key candidate genes related to aluminum tolerance in rapeseed were determined. The results showed that there were 3186 QTGs in the RIL population, 14,232 DEGs and 457 DAMs in the comparison between R and S lines. Lastly, 138 hub genes were selected to have a strong positive or negative correlation with 30 important metabolites (|R|≥ 0.95). These genes were mainly involved in the metabolism of lipids, carbohydrates and secondary metabolites in response to Al toxicity stress. In summary, this study provides an effective method for screening key genes by combining QTLs, transcriptome sequencing and metabolomic analysis, but also lists key genes for exploring the molecular mechanism of Al tolerance in rapeseed seedling roots.
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Affiliation(s)
- Chenyang Li
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China
| | - Hongsong Shi
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China
| | - Lu Xu
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China
| | - Mingli Xing
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China
| | - Xiaoru Wu
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China
| | - Yansong Bai
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China
| | - Mengyuan Niu
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China
| | - Junqi Gao
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China
| | - Qingyuan Zhou
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China.
| | - Cui Cui
- College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China.
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Wang T, Wei L, Wang J, Xie L, Li YY, Ran S, Ren L, Lu K, Li J, Timko MP, Liu L. Integrating GWAS, linkage mapping and gene expression analyses reveals the genetic control of growth period traits in rapeseed ( Brassica napus L.). BIOTECHNOLOGY FOR BIOFUELS 2020; 13:134. [PMID: 32774455 PMCID: PMC7397576 DOI: 10.1186/s13068-020-01774-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 07/24/2020] [Indexed: 05/08/2023]
Abstract
BACKGROUND Brassica napus is one of the most important oilseed crops, and also an important biofuel plant due to its low air pollution and renewability. Growth period are important traits that affect yield and are crucial for its adaptation to different environments in B. napus. RESULTS To elucidate the genetic basis of growth period traits, genome-wide association analysis (GWAS) and linkage mapping were employed to detect the quantitative trait loci (QTL) for days to initial flowering (DIF), days to final flowering (DFF), flowering period (FP), maturity time (MT), and whole growth period (GP). A total of 146 SNPs were identified by association mapping, and 83 QTLs were identified by linkage mapping using the RIL population. Among these QTLs, 19 were pleiotropic SNPs related to multiple traits, and six (q18DFF.A03-2, q18MT.A03-2, q17DFF.A05-1, q18FP.C04, q17DIF.C05 and q17GP.C09) were consistently detected using both mapping methods. Additionally, we performed RNA sequencing to analyze the differential expression of gene (DEG) transcripts between early- and late-flowering lines selected from the RIL population, and the DEGs were integrated with association mapping and linkage analysis to confirm their roles in the growth period. Consequently, 12 candidate genes associated with growth period traits were identified in B. napus. Among these genes, seven have polymorphic sites in the coding sequence and the upstream 2-kb sequence based on the resequencing data. The haplotype BnaSOC1.A05-Haplb and BnaLNK2.C06-Hapla showed more favorable phenotypic traits. CONCLUSIONS The candidate genes identified in this study will contribute to our genetic understanding of growth period traits and can be used as targets for target mutations or marker-assisted breeding for rapeseed adapted to different environments.
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Affiliation(s)
- Tengyue Wang
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
| | - Lijuan Wei
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
| | - Jia Wang
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
| | - Ling Xie
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
| | - Yang Yang Li
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
| | - Shuyao Ran
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
| | - Lanyang Ren
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
| | - Kun Lu
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
| | - Jiana Li
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
| | - Michael P. Timko
- Department of Biology, University of Virginia, Charlottesville, VA 22904 USA
| | - Liezhao Liu
- Chongqing Engineering Research Center for Rapeseed, College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715 China
- Academy of Agricultural Sciences, Southwest University, Beibei, Chongqing, 400715 China
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Bhoite R, Onyemaobi I, Si P, Siddique KHM, Yan G. Identification and validation of QTL and their associated genes for pre-emergent metribuzin tolerance in hexaploid wheat (Triticum aestivum L.). BMC Genet 2018; 19:102. [PMID: 30419811 PMCID: PMC6233490 DOI: 10.1186/s12863-018-0690-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 10/30/2018] [Indexed: 11/17/2022] Open
Abstract
Background Herbicide tolerance is an important trait that allows effective weed management in wheat crops. Genetic knowledge of metribuzin tolerance in wheat is needed to develop new cultivars for the industry. Here, we evaluated metribuzin tolerance in a recombinant inbred line (RIL) mapping population derived from Synthetic W7984 and Opata 85 over two consecutive years to identify quantitative trait loci (QTL) contributing to the trait. Herbicide tolerance was measured by two chlorophyll traits, SPAD chlorophyll content index (CCI) and visual senescence score (SNS). The markers associated with major QTL from Synthetic W7984, positively contributing to reduced phytotoxic effects under herbicide treatment were validated in two F3/4 recombinant inbred populations developed from crosses of Synthetic W7984 × Westonia and Synthetic W7984 × Lang. Results Composite interval mapping (CIM) identified four QTL, two on chromosome 4A and one each on chromosomes 2D and 1A. The chromosomal position of the two QTL mapped on 4A within 10 cM intervals was refined and validated by multiple interval mapping (MIM). The major QTL affecting both measures of tolerance jointly explained 42 and 45% of the phenotypic variation by percentage CCI reduction and SNS, respectively. The identified QTL have a pure additive effect. The metribuzin tolerant allele of markers, Xgwm33 and Xbarc343, conferred lower phytotoxicity and explained the maximum phenotypic variation of 28.8 and 24.5%, respectively. The approximate physical localization of the QTL revealed the presence of five candidate genes (ribulose-bisphosphate carboxylase, oxidoreductase (rbcS), glycosyltransferase, serine/threonine-specific protein kinase and phosphotransferase) with a direct role in photosynthesis and/or metabolic detoxification pathways. Conclusion Metribuzin causes photo-inhibition by interrupting electron flow in PSII. Consequently, chlorophyll traits enabled the measure of high proportion of genetic variability in the mapping population. The validated molecular markers associated with metribuzin tolerance mediating QTL may be used in marker-assisted breeding to select metribuzin tolerant lines. Alternatively, validated favourable alleles could be introgressed into elite wheat cultivars to enhance metribuzin tolerance and improve grain yield in dryland farming for sustainable wheat production. Electronic supplementary material The online version of this article (10.1186/s12863-018-0690-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Roopali Bhoite
- UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia.,The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia
| | - Ifeyinwa Onyemaobi
- UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia.,The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia
| | - Ping Si
- UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia.,The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia
| | - Kadambot H M Siddique
- The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia
| | - Guijun Yan
- UWA School of Agriculture and Environment, The University of Western Australia, Perth, WA, 6001, Australia. .,The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia.
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Grant NP, Mohan A, Sandhu D, Gill KS. Inheritance and Genetic Mapping of the Reduced Height ( Rht18) Gene in Wheat. PLANTS (BASEL, SWITZERLAND) 2018; 7:E58. [PMID: 30011961 PMCID: PMC6161307 DOI: 10.3390/plants7030058] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 07/03/2018] [Accepted: 07/11/2018] [Indexed: 11/23/2022]
Abstract
Short-statured plants revolutionized agriculture during the 1960s due to their ability to resist lodging, increased their response to fertilizers, and improved partitioning of assimilates which led to yield gains. Of more than 21 reduced-height (Rht) genes reported in wheat, only three-Rht-B1b, Rht-D1b, and Rht8-were extensively used in wheat breeding programs. The remaining reduced height mutants have not been utilized in breeding programs due to the lack of characterization. In the present study, we determined the inheritance of Rht18 and developed a genetic linkage map of the region containing Rht18. The height distribution of the F₂ population was skewed towards the mutant parent, indicating that the dwarf allele (Rht18) is semi-dominant over the tall allele (rht18). Rht18 was mapped on chromosome 6A between markers barc146 and cfd190 with a genetic distance of 26.2 and 17.3 cM, respectively. In addition to plant height, agronomically important traits, like awns and tiller numbers, were also studied in the bi-parental population. Although the average tiller number was very similar in both parents, the F₂ population displayed a normal distribution for tiller number with the majority of plants having phenotype similar to the parents. Transgressive segregation was observed for plant height and tiller number in F₂ population. This study enabled us to select a semi-dwarf line with superior agronomic characteristics that could be utilized in a breeding program. The identification of SSRs associated with Rht18 may improve breeders' effectiveness in selecting desired semi-dwarf lines for developing new wheat cultivars.
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Affiliation(s)
- Nathan P Grant
- Department of Crop and Soil Sciences, Washington State University-Pullman, 277 Johnson Hall, PO Box 646420, Pullman, WA 99164-6420, USA.
| | - Amita Mohan
- Department of Crop and Soil Sciences, Washington State University-Pullman, 277 Johnson Hall, PO Box 646420, Pullman, WA 99164-6420, USA.
| | - Devinder Sandhu
- USDA-ARS Salinity Lab., 450 W. Big Springs Rd., Riverside, CA 92507, USA.
| | - Kulvinder S Gill
- Department of Crop and Soil Sciences, Washington State University-Pullman, 277 Johnson Hall, PO Box 646420, Pullman, WA 99164-6420, USA.
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Gelli M, Konda AR, Liu K, Zhang C, Clemente TE, Holding DR, Dweikat IM. Validation of QTL mapping and transcriptome profiling for identification of candidate genes associated with nitrogen stress tolerance in sorghum. BMC PLANT BIOLOGY 2017; 17:123. [PMID: 28697783 PMCID: PMC5505042 DOI: 10.1186/s12870-017-1064-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 06/25/2017] [Indexed: 05/10/2023]
Abstract
BACKGROUND Quantitative trait loci (QTLs) detected in one mapping population may not be detected in other mapping populations at all the time. Therefore, before being used for marker assisted breeding, QTLs need to be validated in different environments and/or genetic backgrounds to rule out statistical anomalies. In this regard, we mapped the QTLs controlling various agronomic traits in a recombinant inbred line (RIL) population in response to Nitrogen (N) stress and validated these with the reported QTLs in our earlier study to find the stable and consistent QTLs across populations. Also, with Illumina RNA-sequencing we checked the differential expression of gene (DEG) transcripts between parents and pools of RILs with high and low nitrogen use efficiency (NUE) and overlaid these DEGs on to the common validated QTLs to find candidate genes associated with N-stress tolerance in sorghum. RESULTS An F7 RIL population derived from a cross between CK60 (N-stress sensitive) and San Chi San (N-stress tolerant) inbred sorghum lines was used to map QTLs for 11 agronomic traits tested under different N-levels. Composite interval mapping analysis detected a total of 32 QTLs for 11 agronomic traits. Validation of these QTLs revealed that of the detected, nine QTLs from this population were consistent with the reported QTLs in earlier study using CK60/China17 RIL population. The validated QTLs were located on chromosomes 1, 6, 7, 8, and 9. In addition, root transcriptomic profiling detected 55 and 20 differentially expressed gene (DEG) transcripts between parents and pools of RILs with high and low NUE respectively. Also, overlay of these DEG transcripts on to the validated QTLs found candidate genes transcripts for NUE and also showed the expected differential expression. For example, DEG transcripts encoding Lysine histidine transporter 1 (LHT1) had abundant expression in San Chi San and the tolerant RIL pool, whereas DEG transcripts encoding seed storage albumin, transcription factor IIIC (TFIIIC) and dwarfing gene (DW2) encoding multidrug resistance-associated protein-9 homolog showed abundant expression in CK60 parent, similar to earlier study. CONCLUSIONS The validated QTLs among different mapping populations would be the most reliable and stable QTLs across germplasm. The DEG transcripts found in the validated QTL regions will serve as future candidate genes for enhancing NUE in sorghum using molecular approaches.
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Affiliation(s)
- Malleswari Gelli
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE, 68583, USA
| | - Anji Reddy Konda
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE, 68588, USA
| | - Kan Liu
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE, 68588, USA
- School of Biological Sciences, University of Nebraska, Lincoln, NE, 68588, USA
| | - Chi Zhang
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE, 68588, USA
- School of Biological Sciences, University of Nebraska, Lincoln, NE, 68588, USA
| | - Thomas E Clemente
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE, 68583, USA
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE, 68588, USA
| | - David R Holding
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE, 68583, USA
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE, 68588, USA
| | - Ismail M Dweikat
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE, 68583, USA.
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Mutti JS, Bhullar RK, Gill KS. Evolution of Gene Expression Balance Among Homeologs of Natural Polyploids. G3 (BETHESDA, MD.) 2017; 7:1225-1237. [PMID: 28193629 PMCID: PMC5386871 DOI: 10.1534/g3.116.038711] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 02/11/2017] [Indexed: 11/18/2022]
Abstract
Polyploidy is a major evolutionary process in eukaryotes, yet the expression balance of homeologs in natural polyploids is largely unknown. To study this expression balance, the expression patterns of 2180 structurally well-characterized genes of wheat were studied, of which 813 had the expected three copies and 375 had less than three. Copy numbers of the remaining 992 ranged from 4 to 14, including homeologs, orthologs, and paralogs. Of the genes with three structural copies corresponding to homeologs, 55% expressed from all three, 38% from two, and the remaining 7% expressed from only one of the three copies. Homeologs of 76-87% of the genes showed differential expression patterns in different tissues, thus have evolved different gene expression controls, possibly resulting in novel functions. Homeologs of 55% of the genes showed tissue-specific expression, with the largest percentage (14%) in the anthers and the smallest (7%) in the pistils. The highest number (1.72/3) of homeologs/gene expression was in the roots and the lowest (1.03/3) in the anthers. As the expression of homeologs changed with changes in structural copy number, about 30% of the genes showed dosage dependence. Chromosomal location also impacted expression pattern as a significantly higher proportion of genes in the proximal regions showed expression from all three copies compared to that present in the distal regions.
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Affiliation(s)
- Jasdeep S Mutti
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164-6420
| | - Ramanjot K Bhullar
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164-6420
| | - Kulvinder S Gill
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164-6420
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Huang L, Raats D, Sela H, Klymiuk V, Lidzbarsky G, Feng L, Krugman T, Fahima T. Evolution and Adaptation of Wild Emmer Wheat Populations to Biotic and Abiotic Stresses. ANNUAL REVIEW OF PHYTOPATHOLOGY 2016; 54:279-301. [PMID: 27296141 DOI: 10.1146/annurev-phyto-080614-120254] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The genetic bottlenecks associated with plant domestication and subsequent selection in man-made agroecosystems have limited the genetic diversity of modern crops and increased their vulnerability to environmental stresses. Wild emmer wheat, the tetraploid progenitor of domesticated wheat, distributed along a wide range of ecogeographical conditions in the Fertile Crescent, has valuable "left behind" adaptive diversity to multiple diseases and environmental stresses. The biotic and abiotic stress responses are conferred by series of genes and quantitative trait loci (QTLs) that control complex resistance pathways. The study of genetic diversity, genomic organization, expression profiles, protein structure and function of biotic and abiotic stress-resistance genes, and QTLs could shed light on the evolutionary history and adaptation mechanisms of wild emmer populations for their natural habitats. The continuous evolution and adaptation of wild emmer to the changing environment provide novel solutions that can contribute to safeguarding food for the rapidly growing human population.
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Affiliation(s)
- Lin Huang
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa 3498838, Israel;
| | - Dina Raats
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa 3498838, Israel;
| | - Hanan Sela
- The Institute for Cereal Crops Improvement, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Valentina Klymiuk
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa 3498838, Israel;
| | - Gabriel Lidzbarsky
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa 3498838, Israel;
| | - Lihua Feng
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa 3498838, Israel;
| | - Tamar Krugman
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa 3498838, Israel;
| | - Tzion Fahima
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa 3498838, Israel;
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Abdollahi Mandoulakani B, Yaniv E, Kalendar R, Raats D, Bariana HS, Bihamta MR, Schulman AH. Development of IRAP- and REMAP-derived SCAR markers for marker-assisted selection of the stripe rust resistance gene Yr15 derived from wild emmer wheat. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2015; 128:211-9. [PMID: 25388968 DOI: 10.1007/s00122-014-2422-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 10/27/2014] [Indexed: 05/08/2023]
Abstract
Yr15 provides broad resistance to stripe rust, an important wheat disease. REMAP- and IRAP-derived co-dominant SCAR markers were developed and localize Yr15 to a 1.2 cM interval. They are reliable across many cultivars. Stripe rust [Pucinia striiformis f.sp. tritici (Pst)] is one of the most important fungal diseases of wheat, found on all continents and in over 60 countries. Wild emmer wheat (Triticum dicoccoides), which is the tetraploid progenitor of durum wheat, is a valuable source of novel stripe rust resistance genes for wheat breeding. T. dicoccoides accession G25 carries Yr15 on chromosome 1BS. Yr15 confers resistance to virtually all tested Pst isolates; it is effective in durum and bread wheat introgressions and their derivatives. Retrotransposons generate polymorphic insertions, which can be scored as Mendelian markers using techniques such as REMAP and IRAP. Six REMAP- and IRAP-derived SCAR markers were mapped using 1,256 F2 plants derived from crosses of the susceptible T. durum accession D447 (DW1) with its resistant BC3F9 and BC3F10 (B9 and B10) near isogenic lines, which carried Yr15 introgressed from G25. The nearest markers segregated 0.1 cM proximally and 1.1 cM distally to Yr15. These markers were also mapped and validated at the same position in another 500 independent F2 plants derived from crosses of B9 and B10 with the susceptible cultivar Langdon (LDN). SC2700 and SC790, defining Yr15 on an interval of 1.2 cM, were found to be reliable and robust co-dominant markers in a wide range of wheat lines and cultivars with and without Yr15. These markers are useful tags in marker-assisted wheat breeding programs that aim to incorporate Yr15 into elite wheat lines and cultivars for durable and broad-spectrum resistance to stripe rust.
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Kapanigowda MH, Payne WA, Rooney WL, Mullet JE, Balota M. Quantitative trait locus mapping of the transpiration ratio related to preflowering drought tolerance in sorghum (Sorghum bicolor). FUNCTIONAL PLANT BIOLOGY : FPB 2014; 41:1049-1065. [PMID: 32481057 DOI: 10.1071/fp13363] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 05/01/2014] [Indexed: 05/25/2023]
Abstract
To meet future food needs, grain production must increase despite reduced water availability, so waterproductivity must rise. One way to do this is to raise the ratio of biomass produced to water transpired, which is controlled by the ratio of CO2 assimilation (A) to transpiration (E) (i.e. the transpiration ratio, A : E divided by vapour pressure deficit) or anything affecting stomatal movement.. We describe the genetic variation and basis of A, E and A : E among 70 recombinant inbred lines (RILs) of sorghum (Sorghum bicolor (L.) Moench), using greenhouse experiments. Experiment 1 used 40% and 80% of field capacity (FC) as water regimes; Experiment 2 used 80% FC. Genotype had a significant effect on A, E and A : E. In Experiment 1, mean values for A : E were 1.2-4.4 mmol CO2 mol-1 H2O kPa-1 and 1.6-3.1 mmol CO2 mol-1 H2O kPa-1 under 40% and 80% FC, respectively. In Experiment 2, values were 5.6-9.8 mmol CO2 mol-1 H2O kPa-1. Pooled data for A : E and A : E VPD-1 from Experiment 1 indicate that A : E fell quickly at temperatures >32.3°C. A : E distributions were skewed. Mean heritabilities for A : E were 0.9 (40% FC) and 0.8 (80% FC). Three significant quantitative trait loci (QTLs) associated with A:E, two on SBI-09 and one on SBI-10, accounted for 17-21% of the phenotypic variation. Subsequent experiments identified 38 QTLs controlling variation in height, flowering, biomass, leaf area, greenness and stomatal density. Colocalisation of A : E QTLs with agronomic traits indicated that these QTLs can be used for improving sorghum performance through marker assisted selection (MAS) under preflowering drought stress.
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Affiliation(s)
| | - William A Payne
- Department of Soil and Crop Sciences, Texas A&M University, College Station, TX 77843-2474, USA
| | - William L Rooney
- Department of Soil and Crop Sciences, Texas A&M University, College Station, TX 77843-2474, USA
| | - John E Mullet
- Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA
| | - Maria Balota
- Virginia Tech Tidewater Agricultural Research and Extension Center, 6321 Holland Road, Suffolk, VA 23437, USA
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Feng L, Hu L, Fu X, Liao H, Li X, Zhan A, Zhang L, Wang S, Huang X, Bao Z. An integrated genetic and cytogenetic map for Zhikong scallop, Chlamys farreri, based on microsatellite markers. PLoS One 2014; 9:e92567. [PMID: 24705086 PMCID: PMC3976258 DOI: 10.1371/journal.pone.0092567] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Accepted: 02/24/2014] [Indexed: 11/18/2022] Open
Abstract
The reliability of genome analysis and proficiency of genetic manipulation requires knowledge of the correspondence between the genetic and cytogenetic maps. In the present study, we integrated cytogenetic and microsatellite-based linkage maps for Zhikong scallop, Chlamys farreri. Thirty-eight marker-anchored BAC clones standing for the 19 linkage groups were used to be FISH probes. Of 38 BAC clones, 30 were successfully located on single chromosome by FISH and used to integrate the genetic and cytogenetic map. Among the 19 linkage groups, 12 linkage groups were physically anchored by 2 markers, 6 linkage groups were anchored by 1 marker, and one linkage group was not anchored any makers by FISH. In addition, using two-color FISH, six linkage groups were distinguished by different chromosomal location; linkage groups LG6 and LG16 were placed on chromosome 10, LG8 and LG18 on chromosome 14. As a result, 18 of 19 linkage groups were localized to 17 pairs of chromosomes of C. farreri. We first integrated genetic and cytogenetic map for C. farreri. These 30 chromosome specific BAC clones in the cytogenetic map could be used to identify chromosomes of C. farreri. The integrated map will greatly facilitate molecular genetic studies that will be helpful for breeding applications in C. farreri and the upcoming genome projects of this species.
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Affiliation(s)
- Liying Feng
- Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Liping Hu
- Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- Yantai Fisheries Research Institute, Yantai, China
| | - Xiaoteng Fu
- Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Huan Liao
- Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Xuan Li
- Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Aibin Zhan
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Lingling Zhang
- Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Shi Wang
- Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Xiaoting Huang
- Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- * E-mail: (XH); (ZB)
| | - Zhenmin Bao
- Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao, China
- * E-mail: (XH); (ZB)
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11
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Raats D, Frenkel Z, Krugman T, Dodek I, Sela H, Simková H, Magni F, Cattonaro F, Vautrin S, Bergès H, Wicker T, Keller B, Leroy P, Philippe R, Paux E, Doležel J, Feuillet C, Korol A, Fahima T. The physical map of wheat chromosome 1BS provides insights into its gene space organization and evolution. Genome Biol 2013; 14:R138. [PMID: 24359668 PMCID: PMC4053865 DOI: 10.1186/gb-2013-14-12-r138] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 12/20/2013] [Indexed: 11/16/2022] Open
Abstract
Background The wheat genome sequence is an essential tool for advanced genomic research and improvements. The generation of a high-quality wheat genome sequence is challenging due to its complex 17 Gb polyploid genome. To overcome these difficulties, sequencing through the construction of BAC-based physical maps of individual chromosomes is employed by the wheat genomics community. Here, we present the construction of the first comprehensive physical map of chromosome 1BS, and illustrate its unique gene space organization and evolution. Results Fingerprinted BAC clones were assembled into 57 long scaffolds, anchored and ordered with 2,438 markers, covering 83% of chromosome 1BS. The BAC-based chromosome 1BS physical map and gene order of the orthologous regions of model grass species were consistent, providing strong support for the reliability of the chromosome 1BS assembly. The gene space for chromosome 1BS spans the entire length of the chromosome arm, with 76% of the genes organized in small gene islands, accompanied by a two-fold increase in gene density from the centromere to the telomere. Conclusions This study provides new evidence on common and chromosome-specific features in the organization and evolution of the wheat genome, including a non-uniform distribution of gene density along the centromere-telomere axis, abundance of non-syntenic genes, the degree of colinearity with other grass genomes and a non-uniform size expansion along the centromere-telomere axis compared with other model cereal genomes. The high-quality physical map constructed in this study provides a solid basis for the assembly of a reference sequence of chromosome 1BS and for breeding applications.
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12
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Nagaraja Reddy R, Madhusudhana R, Murali Mohan S, Chakravarthi DVN, Mehtre SP, Seetharama N, Patil JV. Mapping QTL for grain yield and other agronomic traits in post-rainy sorghum [Sorghum bicolor (L.) Moench]. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2013; 126:1921-1939. [PMID: 23649648 DOI: 10.1007/s00122-013-2107-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 04/20/2013] [Indexed: 06/02/2023]
Abstract
Sorghum, a cereal of economic importance ensures food and fodder security for millions of rural families in the semi-arid tropics. The objective of the present study was to identify and validate quantitative trait loci (QTL) for grain yield and other agronomic traits using replicated phenotypic data sets from three post-rainy dry sorghum crop seasons involving a mapping population with 245 F9 recombinant inbred lines derived from a cross of M35-1 × B35. A genetic linkage map was constructed with 237 markers consisting of 174 genomic, 60 genic and 3 morphological markers. The QTL analysis for 11 traits following composite interval mapping identified 91 QTL with 5-12 QTL for each trait. QTL detected in the population individually explained phenotypic variation between 2.5 and 30.3 % for a given trait and six major genomic regions with QTL effect on multiple traits were identified. Stable QTL across seasons were identified. Of the 60 genic markers mapped, 21 were found at QTL peak or tightly linked with QTL. A gene-based marker XnhsbSFCILP67 (Sb03g028240) on SBI-03, encoding indole-3-acetic acid-amido synthetase GH3.5, was found to be involved in QTL for seven traits. The QTL-linked markers identified for 11 agronomic traits may assist in fine mapping, map-based gene isolation and also for improving post-rainy sorghum through marker-assisted breeding.
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Affiliation(s)
- R Nagaraja Reddy
- Marker-Assisted Selection Laboratory, Directorate of Sorghum Research, Rajendranagar, Hyderabad, India
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13
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Rustgi S, Shafqat MN, Kumar N, Baenziger PS, Ali ML, Dweikat I, Campbell BT, Gill KS. Genetic dissection of yield and its component traits using high-density composite map of wheat chromosome 3A: bridging gaps between QTLs and underlying genes. PLoS One 2013; 8:e70526. [PMID: 23894667 PMCID: PMC3722237 DOI: 10.1371/journal.pone.0070526] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 06/25/2013] [Indexed: 11/18/2022] Open
Abstract
Earlier we identified wheat (Triticum aestivum L.) chromosome 3A as a major determinant of grain yield and its component traits. In the present study, a high-density genetic linkage map of 81 chromosome 3A-specific markers was developed to increase the precision of previously identified yield component QTLs, and to map QTLs for biomass-related traits. Many of the previously identified QTLs for yield and its component traits were confirmed and were localized to narrower intervals. Four novel QTLs one each for shoot biomass (Xcfa2262-Xbcd366), total biomass (wPt2740-Xcfa2076), kernels/spike (KPS) (Xwmc664-Xbarc67), and Pseudocercosporella induced lodging (PsIL) were also detected. The major QTLs identified for grain yield (GY), KPS, grain volume weight (GVWT) and spikes per square meter (SPSM) respectively explained 23.2%, 24.2%, 20.5% and 20.2% of the phenotypic variation. Comparison of the genetic map with the integrated physical map allowed estimation of recombination frequency in the regions of interest and suggested that QTLs for grain yield detected in the marker intervals Xcdo549-Xbarc310 and Xpsp3047-Xbarc356 reside in the high-recombination regions, thus should be amenable to map-based cloning. On the other hand, QTLs for KPS and SPSM flanked by markers Xwmc664 and Xwmc489 mapped in the low-recombination region thus are not suitable for map-based cloning. Comparisons with the rice (Oryza sativa L.) genomic DNA sequence identified 11 candidate genes (CGs) for yield and yield related QTLs of which chromosomal location of two (CKX2 and GID2-like) was confirmed using wheat aneuploids. This study provides necessary information to perform high-resolution mapping for map-based cloning and for CG-based cloning of yield QTLs.
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Affiliation(s)
- Sachin Rustgi
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington, United States of America
| | - Mustafa N. Shafqat
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington, United States of America
- Department of Biosciences, COMSATS Institute of Information Technology, Islamabad, Pakistan
| | - Neeraj Kumar
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington, United States of America
| | - P. Stephen Baenziger
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - M. Liakat Ali
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - Ismail Dweikat
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - B. Todd Campbell
- Agricultural Research Service, Coastal Plains Soil, Water, and Plant Research Center, Florence, South Carolina, United States of America
| | - Kulvinder Singh Gill
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington, United States of America
- * E-mail:
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14
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Olivera PD, Kilian A, Wenzl P, Steffenson BJ. Development of a genetic linkage map for Sharon goatgrass (Aegilops sharonensis) and mapping of a leaf rust resistance gene. Genome 2013; 56:367-76. [PMID: 24099389 DOI: 10.1139/gen-2013-0065] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Aegilops sharonensis (Sharon goatgrass), a diploid wheat relative, is known to be a rich source of disease resistance genes for wheat improvement. To facilitate the transfer of these genes into wheat, information on their chromosomal location is important. A genetic linkage map of Ae. sharonensis was constructed based on 179 F2 plants derived from a cross between accessions resistant (1644) and susceptible (1193) to wheat leaf rust. The linkage map was based on 389 markers (377 Diversity Arrays Technology (DArT) and 12 simple sequence repeat (SSR) loci) and was comprised of 10 linkage groups, ranging from 2.3 to 124.6 cM. The total genetic length of the map was 818.0 cM, with an average interval distance between markers of 3.63 cM. Based on the chromosomal location of 115 markers previously mapped in wheat, the four linkage groups of A, B, C, and E were assigned to Ae. sharonensis (S(sh)) and homoeologous wheat chromosomes 6, 1, 3, and 2. The single dominant gene (designated LrAeSh1644) conferring resistance to leaf rust race THBJ in accession 1644 was positioned on linkage group A (chromosome 6S(sh)) and was flanked by DArT markers wpt-9881 (at 1.9 cM distal from the gene) and wpt-6925 (4.5 cM proximal). This study clearly demonstrates the utility of DArT for genotyping uncharacterized species and tagging resistance genes where pertinent genomic information is lacking.
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Affiliation(s)
- P D Olivera
- a Department of Plant Pathology, University of Minnesota, St. Paul, MN 55108, USA
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15
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Wang ZN, Banik M, Cloutier S. Divergent evolutionary mechanisms of co-located Tak/Lrk and Glu-D3 loci revealed by comparative analysis of grass genomes. Genome 2013; 56:195-204. [PMID: 23706072 DOI: 10.1139/gen-2012-0172] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Seed storage and disease resistance proteins are major traits of wheat. The study of their gene organization and evolution has some implications in breeding. In this study, we characterized the hexaploid wheat D-genome BAC clone TaBAC703A9 that contains a low molecular weight glutenin locus (Glu-D3) and a resistance gene analogue cluster. With a gene density of one gene per 4.8 kb, the cluster contains four resistance gene analogues, namely Tak703-1, Lrr703, Tak703, and Lrk703. This structural cluster unit was conserved across nine grass genomes, but divergent evolutionary mechanisms have been involved in shaping the Tak/Lrk loci in the different species. Gene duplication was the major force for the Tak/Lrk evolution in oats, maize, barley, wheat, sorghum, and Brachypodium, while tandem duplication drove the expansion of this locus in japonica rice. Despite the close proximity of the Glu-D3 and the Tak/Lrk loci in wheat, the evolutionary mechanisms that drove their amplification differ. The Glu-D3 region had a lower gene density, and its amplification was driven by retroelements.
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Affiliation(s)
- Zi-Ning Wang
- Cereal Research Centre, Agriculture and Agri-Food Canada, 195 Dafoe Road, Winnipeg MB R3T 2M9, Canada
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16
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Tiwari VK, Riera-Lizarazu O, Gunn HL, Lopez K, Iqbal MJ, Kianian SF, Leonard JM. Endosperm tolerance of paternal aneuploidy allows radiation hybrid mapping of the wheat D-genome and a measure of γ ray-induced chromosome breaks. PLoS One 2012; 7:e48815. [PMID: 23144983 PMCID: PMC3492231 DOI: 10.1371/journal.pone.0048815] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 10/01/2012] [Indexed: 11/21/2022] Open
Abstract
Physical mapping and genome sequencing are underway for the ≈17 Gb wheat genome. Physical mapping methods independent of meiotic recombination, such as radiation hybrid (RH) mapping, will aid precise anchoring of BAC contigs in the large regions of suppressed recombination in Triticeae genomes. Reports of endosperm development following pollination with irradiated pollen at dosages that cause embryo abortion prompted us to investigate endosperm as a potential source of RH mapping germplasm. Here, we report a novel approach to construct RH based physical maps of all seven D-genome chromosomes of the hexaploid wheat ‘Chinese Spring’, simultaneously. An 81-member subset of endosperm samples derived from 20-Gy irradiated pollen was genotyped for deletions, and 737 markers were mapped on seven D-genome chromosomes. Analysis of well-defined regions of six chromosomes suggested a map resolution of ∼830 kb could be achieved; this estimate was validated with assays of markers from a sequenced contig. We estimate that the panel contains ∼6,000 deletion bins for D-genome chromosomes and will require ∼18,000 markers for high resolution mapping. Map-based deletion estimates revealed a majority of 1–20 Mb interstitial deletions suggesting mutagenic repair of double-strand breaks in pollen provides a useful resource for RH mapping and map based cloning studies.
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Affiliation(s)
- Vijay K. Tiwari
- Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon, United States of America
| | - Oscar Riera-Lizarazu
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Andhra Pradesh, India
| | - Hilary L. Gunn
- Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon, United States of America
| | - KaSandra Lopez
- Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon, United States of America
| | - M. Javed Iqbal
- Department of Plant Sciences, North Dakota State University, Fargo, North Dakota, United States of America
| | - Shahryar F. Kianian
- Department of Plant Sciences, North Dakota State University, Fargo, North Dakota, United States of America
| | - Jeffrey M. Leonard
- Department of Crop and Soil Science, Oregon State University, Corvallis, Oregon, United States of America
- * E-mail:
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17
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Huang XQ, Röder MS. High-density genetic and physical bin mapping of wheat chromosome 1D reveals that the powdery mildew resistance gene Pm24 is located in a highly recombinogenic region. Genetica 2011; 139:1179-87. [PMID: 22143458 DOI: 10.1007/s10709-011-9620-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 11/29/2011] [Indexed: 11/25/2022]
Abstract
Genetic maps of wheat chromosome 1D consisting of 57 microsatellite marker loci were constructed using Chinese Spring (CS) × Chiyacao F(2) and the International Triticeae Mapping Initiative (ITMI) recombinant inbred lines (RILs) mapping populations. Marker order was consistent, but genetic distances of neighboring markers were different in two populations. Physical bin map of 57 microsatellite marker loci was generated by means of 10 CS 1D deletion lines. The physical bin mapping indicated that microsatellite marker loci were not randomly distributed on chromosome 1D. Nineteen of the 24 (79.2%) microsatellite markers were mapped in the distal 30% genomic region of 1DS, whereas 25 of the 33 (75.8%) markers were assigned to the distal 59% region of 1DL. The powdery mildew resistance gene Pm24, originating from the Chinese wheat landrace Chiyacao, was previously mapped in the vicinity of the centromere on the short arm of chromosome 1D. A high density genetic map of chromosome 1D was constructed, consisting of 36 markers and Pm24, with a total map length of 292.7 cM. Twelve marker loci were found to be closely linked to Pm24. Pm24 was flanked by Xgwm789 (Xgwm603) and Xbarc229 with genetic distances of 2.4 and 3.6 cM, respectively, whereas a microsatellite marker Xgwm1291 co-segregated with Pm24. The microsatellite marker Xgwm1291 was assigned to the bin 1DS5-0.70-1.00 of the chromosome arm 1DS. It could be concluded that Pm24 is located in the '1S0.8 gene-rich region', a highly recombinogenic region of wheat. The results presented here would provide a start point for the map-based cloning of Pm24.
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Affiliation(s)
- Xiu-Qiang Huang
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, 06466 Gatersleben, Germany.
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18
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Alheit KV, Reif JC, Maurer HP, Hahn V, Weissmann EA, Miedaner T, Würschum T. Detection of segregation distortion loci in triticale (x Triticosecale Wittmack) based on a high-density DArT marker consensus genetic linkage map. BMC Genomics 2011; 12:380. [PMID: 21798064 PMCID: PMC3156787 DOI: 10.1186/1471-2164-12-380] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 07/28/2011] [Indexed: 11/10/2022] Open
Abstract
Background Triticale is adapted to a wide range of abiotic stress conditions, is an important high-quality feed stock and produces similar grain yield but more biomass compared to other crops. Modern genomic approaches aimed at enhancing breeding progress in cereals require high-quality genetic linkage maps. Consensus maps are genetic maps that are created by a joint analysis of the data from several segregating populations and different approaches are available for their construction. The phenomenon that alleles at a locus deviate from the Mendelian expectation has been defined as segregation distortion. The study of segregation distortion is of particular interest in doubled haploid (DH) populations due to the selection pressure exerted on the plants during the process of their establishment. Results The final consensus map, constructed out of six segregating populations derived from nine parental lines, incorporated 2555 DArT markers mapped to 2602 loci (1929 unique). The map spanned 2309.9 cM with an average number of 123.9 loci per chromosome and an average marker density of one unique locus every 1.2 cM. The R genome showed the highest marker coverage followed by the B genome and the A genome. In general, locus order was well maintained between the consensus linkage map and the component maps. However, we observed several groups of loci for which the colinearity was slightly uneven. Among the 2602 loci mapped on the consensus map, 886 showed distorted segregation in at least one of the individual mapping populations. In several DH populations derived by androgenesis, we found chromosomes (2B, 3B, 1R, 2R, 4R and 7R) containing regions where markers exhibited a distorted segregation pattern. In addition, we observed evidence for segregation distortion between pairs of loci caused either by a predominance of parental or recombinant genotypes. Conclusions We have constructed a reliable, high-density DArT marker consensus genetic linkage map as a basis for genomic approaches in triticale research and breeding, for example for multiple-line cross QTL mapping experiments. The results of our study exemplify the tremendous impact of different DH production techniques on allele frequencies and segregation distortion covering whole chromosomes.
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Affiliation(s)
- Katharina V Alheit
- State Plant Breeding Institute, University of Hohenheim, 70593 Stuttgart, Germany
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19
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Aruna C, Bhagwat VR, Madhusudhana R, Sharma V, Hussain T, Ghorade RB, Khandalkar HG, Audilakshmi S, Seetharama N. Identification and validation of genomic regions that affect shoot fly resistance in sorghum [Sorghum bicolor (L.) Moench]. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2011; 122:1617-30. [PMID: 21387095 DOI: 10.1007/s00122-011-1559-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Accepted: 02/12/2011] [Indexed: 05/20/2023]
Abstract
Shoot fly is one of the most important pests affecting the sorghum production. The identification of quantitative trait loci (QTL) affecting shoot fly resistance enables to understand the underlying genetic mechanisms and genetic basis of complex interactions among the component traits. The aim of the present study was to detect QTL for shoot fly resistance and the associated traits using a population of 210 RILs of the cross 27B (susceptible) × IS2122 (resistant). RIL population was phenotyped in eight environments for shoot fly resistance (deadheart percentage), and in three environments for the component traits, such as glossiness, seedling vigor and trichome density. Linkage map was constructed with 149 marker loci comprising 127 genomic-microsatellite, 21 genic-microsatellite and one morphological marker. QTL analysis was performed by using MQM approach. 25 QTL (five each for leaf glossiness and seedling vigor, 10 for deadhearts, two for adaxial trichome density and three for abaxial trichome density) were detected in individual and across environments. The LOD and R (2) (%) values of QTL ranged from 2.44 to 24.1 and 4.3 to 44.1%, respectively. For most of the QTLs, the resistant parent, IS2122 contributed alleles for resistance; while at two QTL regions, the susceptible parent 27B also contributed for resistance traits. Three genomic regions affected multiple traits, suggesting the phenomenon of pleiotrophy or tight linkage. Stable QTL were identified for the traits across different environments, and genetic backgrounds by comparing the QTL in the study with previously reported QTL in sorghum. For majority of the QTLs, possible candidate genes were identified. The QTLs identified will enable marker assisted breeding for shoot fly resistance in sorghum.
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Affiliation(s)
- C Aruna
- Directorate of Sorghum Research, Hyderabad, India.
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20
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The compact Brachypodium genome conserves centromeric regions of a common ancestor with wheat and rice. Funct Integr Genomics 2010; 10:477-92. [DOI: 10.1007/s10142-010-0190-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 08/20/2010] [Accepted: 08/24/2010] [Indexed: 12/19/2022]
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21
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Abeysekara NS, Friesen TL, Keller B, Faris JD. Identification and characterization of a novel host-toxin interaction in the wheat-Stagonospora nodorum pathosystem. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2009; 120:117-26. [PMID: 19816671 DOI: 10.1007/s00122-009-1163-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Accepted: 09/11/2009] [Indexed: 05/02/2023]
Abstract
Stagonospora nodorum, casual agent of Stagonospora nodorum blotch (SNB) of wheat, produces a number of host-selective toxins (HSTs) known to be important in disease. To date, four HSTs and corresponding host sensitivity genes have been reported, and all four host-toxin interactions are significant factors in the development of disease. Here, we describe the identification and partial characterization of a fifth S. nodorum produced HST designated SnTox4. The toxin, estimated to be 10-30 kDa in size, was found to be proteinaceous in nature. Sensitivity to SnTox4 is governed by a single dominant gene, designated Snn4, which mapped to the short arm of wheat chromosome 1A in a recombinant inbred (RI) population. The compatible Snn4-SnTox4 interaction is light dependent and results in a mottled necrotic reaction, which is different from the severe necrosis that results from other host-toxin interactions in the wheat-S. nodorum pathosystem. QTL analysis in a population of 200 RI lines derived from the Swiss winter wheat varieties Arina and Forno revealed a major QTL for SNB susceptibility that coincided with the Snn4 locus. This QTL, designated QSnb.fcu-1A, explained 41.0% of the variation in disease on leaves of seedlings indicating that a compatible Snn4-SnTox4 interaction plays a major role in the development of SNB in this population. Additional minor QTL detected on the short arms of chromosomes 2A and 3A accounted for 5.4 and 6.0% of the variation, respectively. The effects of the three QTL were largely additive, and together they explained 50% of the total phenotypic variation. These results provide further evidence that host-toxin interactions in the wheat-S. nodorum pathosystem follow an inverse gene-for-gene model.
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Affiliation(s)
- Nilwala S Abeysekara
- Department of Plant Sciences, North Dakota State University, Fargo, ND, 58105, USA
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Satish K, Srinivas G, Madhusudhana R, Padmaja PG, Nagaraja Reddy R, Murali Mohan S, Seetharama N. Identification of quantitative trait loci for resistance to shoot fly in sorghum [Sorghum bicolor (L.) Moench]. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2009; 119:1425-39. [PMID: 19763534 DOI: 10.1007/s00122-009-1145-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2009] [Accepted: 08/21/2009] [Indexed: 05/20/2023]
Abstract
The shoot fly is one of the most destructive insect pests of sorghum at the seedling stage. Deployment of cultivars with improved shoot fly resistance would be facilitated by the use of molecular markers linked to QTL. The objective of this study was to dissect the genetic basis of resistance into QTL, using replicated phenotypic data sets obtained from four test environments, and a 162 microsatellite marker-based linkage map constructed using 168 RILs of the cross 296B (susceptible) x IS18551 (resistant). Considering five component traits and four environments, a total of 29 QTL were detected by multiple QTL mapping (MQM) viz., four each for leaf glossiness and seedling vigor, seven for oviposition, six for deadhearts, two for adaxial trichome density and six for abaxial trichome density. The LOD and R (2) (%) values of QTL ranged from 2.6 to 15.0 and 5.0 to 33%, respectively. For most of the QTL, IS18551 contributed resistance alleles; however, at six QTL, alleles from 296B also contributed to resistance. QTL of the related component traits were co-localized, suggesting pleiotropy or tight linkage of genes. The new morphological marker Trit for trichome type was associated with the major QTL for component traits of resistance. Interestingly, QTL identified in this study correspond to QTL/genes for insect resistance at the syntenic maize genomic regions, suggesting the conservation of insect resistance loci between these crops. For majority of the QTL, possible candidate genes lie within or very near the ascribed confidence intervals in sorghum. Finally, the QTL identified in the study should provide a foundation for marker-assisted selection (MAS) programs for improving shoot fly resistance in sorghum.
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Affiliation(s)
- K Satish
- Directorate of Sorghum Research, Rajendranagar, Hyderabad, 500030, India
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A molecular-cytogenetic method for locating genes to pericentromeric regions facilitates a genomewide comparison of synteny between the centromeric regions of wheat and rice. Genetics 2009; 183:1235-47. [PMID: 19797045 DOI: 10.1534/genetics.109.107409] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Centromeres, because of their repeat structure and lack of sequence conservation, are difficult to assemble and compare across organisms. It was recently discovered that rice centromeres often contain genes. This suggested a method for studying centromere homologies between wheat and rice chromosomes by mapping rice centromeric genes onto wheat aneuploid stocks. Three of the seven cDNA clones of centromeric genes from rice centromere 8 (Cen8), 6729.t09, 6729.t10, and 6730.t11 which lie in the Cen8 kinetochore region, and three wheat ESTs, BJ301191, BJ305475, and BJ280500, with similarity to sequences of rice centromeric genes, were mapped to the centromeric regions of the wheat group-7 (W7) chromosomes. A possible pericentric inversion in chromosome 7D was detected. Genomewide comparison of wheat ESTs that mapped to centromeric regions against rice genome sequences revealed high conservation and a one-to-one correspondence of centromeric regions between wheat and rice chromosome pairs W1-R5, W2-R7, W3-R1, W5-R12, W6-R2, and W7-R8. The W4 centromere may share homology with R3 only or with R3 + R11. Wheat ESTs that mapped to the pericentromeric region of the group-5 long arm anchored to the rice BACs located in the recently duplicated region at the distal ends of the short arms of rice chromosomes 11 and 12. A pericentric inversion specific to the rice lineage was detected. The depicted framework provides a working model for further studies on the structure and evolution of cereal chromosome centromeres.
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Sood S, Kuraparthy V, Bai G, Gill BS. The major threshability genes soft glume (sog) and tenacious glume (Tg), of diploid and polyploid wheat, trace their origin to independent mutations at non-orthologous loci. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2009; 119:341-51. [PMID: 19421730 DOI: 10.1007/s00122-009-1043-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Accepted: 04/09/2009] [Indexed: 05/23/2023]
Abstract
Threshability is an important crop domestication trait. The wild wheat progenitors have tough glumes enveloping the floret that make spikes difficult to thresh, whereas cultivated wheats have soft glumes and are free-threshing. In hexaploid wheat, the glume tenacity gene Tg along with the major domestication locus Q control threshability. The Q gene was isolated recently and found to be a member of the AP2 class of transcription factors. However, only a few studies have reported on the tough glume trait. Here, we report comparative mapping of the soft glume (sog) gene of diploid Triticum monococcum L. and tenacious glume (Tg) gene of hexaploid T. aestivum L. using chromosome-specific SSR and RFLP markers. The sog gene was flanked by Xgwm71 and Xbcd120 in a 6.8 cM interval on chromosome 2A(m)S of T. monococcum whereas Tg was targeted to a 8.1 cM interval flanked by Xwmc503 and Xfba88 on chromosome 2DS of T. aestivum. Deletion bin mapping of the flanking markers assigned sog close to the centromere on 2AS, whereas Tg was mapped to the most distal region on 2DS. Both 2AS and 2DS maps were colinear ruling out the role of chromosome rearrangements for their non-syntenic positions. Therefore, sog and Tg are not true orthologues suggesting the possibility of a diverse origin.
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Affiliation(s)
- Shilpa Sood
- Department of Plant Pathology, Wheat Genetic and Genomic Resources Center, Kansas State University, Manhattan, KS 66506-5502, USA.
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Randhawa HS, Singh J, Lemaux PG, Gill KS. Mapping barleyDsinsertions using wheat deletion lines reveals high insertion frequencies in gene-rich regions with high to moderate recombination rates. Genome 2009; 52:566-75. [DOI: 10.1139/g09-029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Gene distribution is highly uneven in the large genomes of barley and wheat; however, location, order, and gene density of gene-containing regions are very similar between the two genomes. Flanking sequences from 35 unique, single-copy, barley Ds insertion events were physically mapped using wheat nullisomic-tetrasomic, ditelosomic, and deletion lines. Of the 35 sequences, 23 (66%) detected 34 loci mapping on all 7 homoeologous wheat groups. Seven sequences were not mapped owing to lack of polymorphism and the remaining 5 (14%) were barley-specific. All 34 loci physically mapped to the previously identified gene-rich regions (GRRs) of wheat, making the contained genes candidates for targeted mutagenesis by remobilization. Transpositions occurred preferentially into GRRs with higher recombination rates. The GRRs containing 17 of the 23 Ds insertions accounted for 60%–89% of the respective arm’s recombination. The remaining 6 (17%) insertions mapped to GRRs with <15% of the arm’s recombination. Overall, kb/cM estimates for the Ds-containing GRRs were twofold higher than those for regions without insertions. These results suggest that all genes may be targeted by transposon-based gene cloning, although the transposition frequency for genes present in recombination-poor regions is significantly less than that present in highly recombinogenic regions.
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Affiliation(s)
- Harpinder S. Randhawa
- Department of Crop and Soil Sciences, 277 Johnson Hall, P.O. Box 646420, Washington State University, Pullman, WA 99164-6420, USA
- Department of Plant Science, McGill University, Macdonald Campus, 21111 Lakeshore Road, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3102, USA
| | - Jaswinder Singh
- Department of Crop and Soil Sciences, 277 Johnson Hall, P.O. Box 646420, Washington State University, Pullman, WA 99164-6420, USA
- Department of Plant Science, McGill University, Macdonald Campus, 21111 Lakeshore Road, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3102, USA
| | - Peggy G. Lemaux
- Department of Crop and Soil Sciences, 277 Johnson Hall, P.O. Box 646420, Washington State University, Pullman, WA 99164-6420, USA
- Department of Plant Science, McGill University, Macdonald Campus, 21111 Lakeshore Road, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3102, USA
| | - Kulvinder S. Gill
- Department of Crop and Soil Sciences, 277 Johnson Hall, P.O. Box 646420, Washington State University, Pullman, WA 99164-6420, USA
- Department of Plant Science, McGill University, Macdonald Campus, 21111 Lakeshore Road, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3102, USA
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Srinivas G, Satish K, Madhusudhana R, Reddy RN, Mohan SM, Seetharama N. Identification of quantitative trait loci for agronomically important traits and their association with genic-microsatellite markers in sorghum. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2009; 118:1439-54. [PMID: 19274449 DOI: 10.1007/s00122-009-0993-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Accepted: 02/10/2009] [Indexed: 05/20/2023]
Abstract
The identification of quantitative trait loci (QTLs) affecting agronomically important traits enable to understand their underlying genetic mechanisms and genetic basis of their complex interactions. The aim of the present study was to detect QTLs for 12 agronomic traits related to staygreen, plant early development, grain yield and its components, and some growth characters by analyzing replicated phenotypic datasets from three crop seasons, using the population of 168 F(7) RILs of the cross 296B x IS18551. In addition, we report mapping of a subset of genic-microsatellite markers. A linkage map was constructed with 152 marker loci comprising 149 microsatellites (100 genomic- and 49 genic-microsatellites) and three morphological markers. QTL analysis was performed by using MQM approach. Forty-nine QTLs were detected, across environments or in individual environments, with 1-9 QTLs for each trait. Individual QTL accounted for 5.2-50.4% of phenotypic variance. Several genomic regions affected multiple traits, suggesting the phenomenon of pleiotropy or tight linkage. Stable QTLs were identified for studied traits across different environments, and genetic backgrounds by comparing the QTLs in the study with previously reported QTLs in sorghum. Of the 49 mapped genic-markers, 18 were detected associating either closely or exactly as the QTL positions of agronomic traits. EST marker Dsenhsbm19, coding for a key regulator (EIL-1) of ethylene biosynthesis, was identified co-located with the QTLs for plant early development and staygreen trait, a probable candidate gene for these traits. Similarly, such exact co-locations between EST markers and QTLs were observed in four other instances. Collectively, the QTLs/markers identified in the study are likely candidates for improving the sorghum performance through MAS and map-based gene isolations.
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Affiliation(s)
- G Srinivas
- National Research Center for Sorghum, Rajendranagar, Hyderabad, 500030, India
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Pouilly N, Delourme R, Alix K, Jenczewski E. Repetitive sequence-derived markers tag centromeres and telomeres and provide insights into chromosome evolution in Brassica napus. Chromosome Res 2008; 16:683-700. [PMID: 18535916 DOI: 10.1007/s10577-008-1219-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2008] [Revised: 03/17/2008] [Accepted: 03/17/2008] [Indexed: 10/22/2022]
Abstract
Centromeres and telomeres are obvious markers on chromosomes but their location on genetic maps is difficult to determine, which hampers many basic and applied research programmes. In this study, we used the characteristic distribution of five Brassica repeated sequences to generate physically anchored molecular markers tentatively tagging Brassica centromeres (84 markers) and telomeres (31 markers). These markers were mapped to the existing oilseed rape genetic map. Clusters of centromere-related loci were observed on 14 linkage groups; in addition to previous reports, we could thus provide information about the most likely position of centromeres on 17 of the 19 B. napus linkage groups. The location of centromeres on linkage groups usually matches their position on chromosomes and coincides with sites of evolutionary breakage between chromosomes. Most telomere sequence-derived markers mapped interstitially or in the proximity of centromeres; this result echoes previous reports on many eukaryote genomes and may reflect different forms of chromosome evolution. Seven telomere sequence-derived markers were located at the outermost positions of seven linkage groups and therefore probably tagged telomeres.
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Affiliation(s)
- Nicolas Pouilly
- INRA, Agrocampus Rennes, Université Rennes 1, UMR 118 Amélioration des Plantes et Biotechnologies Végétales, Le Rheu Cedex, France
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Bhat PR, Lukaszewski A, Cui X, Xu J, Svensson JT, Wanamaker S, Waines JG, Close TJ. Mapping translocation breakpoints using a wheat microarray. Nucleic Acids Res 2007; 35:2936-43. [PMID: 17439961 PMCID: PMC1888831 DOI: 10.1093/nar/gkm148] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We report mapping of translocation breakpoints using a microarray. We used complex RNA to compare normal hexaploid wheat (17,000 Mb genome) to a ditelosomic stock missing the short arm of chromosome 1B (1BS) and wheat-rye translocations that replace portions of 1BS with rye 1RS. Transcripts detected by a probe set can come from all three Triticeae genomes in ABD hexaploid wheat, and sequences of homoeologous genes on 1AS, 1BS and 1DS often differ from each other. Absence or replacement of 1BS therefore must sometimes result in patterns within a probe set that deviate from hexaploid wheat. We termed these 'high variance probe sets' (HVPs) and examined the extent to which HVPs associated with 1BS aneuploidy are related to rice genes on syntenic rice chromosome 5 short arm (5S). We observed an enrichment of such probe sets to 15-20% of all HVPs, while 1BS represents approximately 2% of the total genome. In total 257 HVPs constitute wheat 1BS markers. Two wheat-rye translocations subdivided 1BS HVPs into three groups, allocating translocation breakpoints to narrow intervals defined by rice 5S coordinates. This approach could be extended to the entire wheat genome or any organism with suitable aneuploid or translocation stocks.
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Affiliation(s)
- Prasanna R. Bhat
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA 92521-0124, Department of Statistics, University of California, Riverside, California, USA 92521-0124 and Department of Statistics, East China Normal University, Shanghai, China, 200062
| | - Adam Lukaszewski
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA 92521-0124, Department of Statistics, University of California, Riverside, California, USA 92521-0124 and Department of Statistics, East China Normal University, Shanghai, China, 200062
| | - Xinping Cui
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA 92521-0124, Department of Statistics, University of California, Riverside, California, USA 92521-0124 and Department of Statistics, East China Normal University, Shanghai, China, 200062
| | - Jin Xu
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA 92521-0124, Department of Statistics, University of California, Riverside, California, USA 92521-0124 and Department of Statistics, East China Normal University, Shanghai, China, 200062
| | - Jan T. Svensson
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA 92521-0124, Department of Statistics, University of California, Riverside, California, USA 92521-0124 and Department of Statistics, East China Normal University, Shanghai, China, 200062
| | - Steve Wanamaker
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA 92521-0124, Department of Statistics, University of California, Riverside, California, USA 92521-0124 and Department of Statistics, East China Normal University, Shanghai, China, 200062
| | - J. Giles Waines
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA 92521-0124, Department of Statistics, University of California, Riverside, California, USA 92521-0124 and Department of Statistics, East China Normal University, Shanghai, China, 200062
| | - Timothy J. Close
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA 92521-0124, Department of Statistics, University of California, Riverside, California, USA 92521-0124 and Department of Statistics, East China Normal University, Shanghai, China, 200062
- *To whom correspondence should be addressed. +1- 951 827 3318+1 951 827 4437
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Janda J, Safár J, Kubaláková M, Bartos J, Kovárová P, Suchánková P, Pateyron S, Cíhalíková J, Sourdille P, Simková H, Faivre-Rampant P, Hribová E, Bernard M, Lukaszewski A, Dolezel J, Chalhoub B. Advanced resources for plant genomics: a BAC library specific for the short arm of wheat chromosome 1B. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 47:977-86. [PMID: 16911585 DOI: 10.1111/j.1365-313x.2006.02840.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Common wheat (Triticum aestivum L., 2n = 6x = 42) is a polyploid species possessing one of the largest genomes among the cultivated crops (1C is approximately 17 000 Mb). The presence of three homoeologous genomes (A, B and D), and the prevalence of repetitive DNA make sequencing the wheat genome a daunting task. We have developed a novel 'chromosome arm-based' strategy for wheat genome sequencing to simplify this task; this relies on sub-genomic libraries of large DNA inserts. In this paper, we used a di-telosomic line of wheat to isolate six million copies of the short arm of chromosome 1B (1BS) by flow sorting. Chromosomal DNA was partially digested with HindIII and used to construct an arm-specific BAC library. The library consists of 65 280 clones with an average insert size of 82 kb. Almost half of the library (45%) has inserts larger than 100 kb, while 18% of the inserts range in size between 75 and 100 kb, and 37% are shorter than 75 kb. We estimated the chromosome arm coverage to be 14.5-fold, giving a 99.9% probability of identifying a clone corresponding to any sequence on the short arm of 1B. Each chromosome arm in wheat can be flow sorted from an appropriate cytogenetic stock, and we envisage that the availability of chromosome arm-specific BAC resources in wheat will greatly facilitate the development of ready-to-sequence physical maps and map-based gene cloning.
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Affiliation(s)
- Jaroslav Janda
- Laboratory of Molecular Cytogenetics and Cytometry, Institute of Experimental Botany, Sokolovská 6, CZ-77200 Olomouc, Czech Republic
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30
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Huang XQ, Cloutier S, Lycar L, Radovanovic N, Humphreys DG, Noll JS, Somers DJ, Brown PD. Molecular detection of QTLs for agronomic and quality traits in a doubled haploid population derived from two Canadian wheats (Triticum aestivum L.). TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2006; 113:753-66. [PMID: 16838135 DOI: 10.1007/s00122-006-0346-7] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2005] [Accepted: 06/11/2006] [Indexed: 05/10/2023]
Abstract
Development of high-yielding wheat varieties with good end-use quality has always been a major concern for wheat breeders. To genetically dissect quantitative trait loci (QTLs) for yield-related traits such as grain yield, plant height, maturity, lodging, test weight and thousand-grain weight, and for quality traits such as grain and flour protein content, gluten strength as evaluated by mixograph and SDS sedimentation volume, an F1-derived doubled haploid (DH) population of 185 individuals was developed from a cross between a Canadian wheat variety "AC Karma" and a breeding line 87E03-S2B1. A genetic map was constructed based on 167 marker loci, consisting of 160 microsatellite loci, three HMW glutenin subunit loci: Glu-A1, Glu-B1 and Glu-D1, and four STS-PCR markers. Data for investigated traits were collected from three to four environments in Manitoba, Canada. QTL analyses were performed using composite interval mapping. A total of 50 QTLs were detected, 24 for agronomic traits and 26 for quality-related traits. Many QTLs for correlated traits were mapped in the same genomic regions forming QTL clusters. The largest QTL clusters, consisting of up to nine QTLs, were found on chromosomes 1D and 4D. HMW glutenin subunits at Glu-1 loci had the largest effect on breadmaking quality; however, other genomic regions also contributed genetically to breadmaking quality. QTLs detected in the present study are compared with other QTL analyses in wheat.
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Affiliation(s)
- X Q Huang
- Cereal Research Centre, Agriculture and Agri-Food Canada, 195 Dafoe Road, R3T 2M9, MB Winnipeg, Canada
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31
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Semagn K, Bjørnstad A, Skinnes H, Marøy AG, Tarkegne Y, William M. Distribution of DArT, AFLP, and SSR markers in a genetic linkage map of a doubled-haploid hexaploid wheat population. Genome 2006; 49:545-55. [PMID: 16767179 DOI: 10.1139/g06-002] [Citation(s) in RCA: 138] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A genetic linkage mapping study was conducted in 93 doubled-haploid lines derived from a cross between Triticum aestivum L. em. Thell 'Arina' and a Norwegian spring wheat breeding line, NK93604, using diversity arrays technology (DArT), amplified fragment length polymorphism (AFLP), and simple sequence repeat (SSR) markers. The objective of this study was to understand the distribution, redundancy, and segregation distortion of DArT markers in comparison with AFLP and SSR markers. The map contains a total of 624 markers with 189 DArTs, 165 AFLPs and 270 SSRs, and spans 2595.5 cM. All 3 marker types showed significant (p < 0.01) segregation distortion, but it was higher for AFLPs (24.2%) and SSRs (22.6%) than for DArTs (13.8%). The overall segregation distortion was 20.4%. DArTs showed the highest frequency of clustering (27.0%) at < 0.5 cM intervals between consecutive markers, which is 3 and 15 times higher than SSRs (8.9%) and AFLPs (1.8%), respectively. This high proportion of clustering of DArT markers may be indicative of gene-rich regions and (or) the result of inclusion of redundant clones in the genomic representations, which was supported by the presence of very high correlation coefficients (r > 0.98) and multicollinearity among the clustered markers. The present study is the first to compare the utility of DArT with AFLP and SSR markers, and the present map has been successfully used to identify novel QTLs for resistance to Fusarium head blight and powdery mildew and for anther extrusion, leaf segment incubation, and latency.Key words: 'Arina', diversity arrays technology, double haploid, genetic map, marker clustering, microsatellite.
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Affiliation(s)
- Kassa Semagn
- Department of Plant and Environmental Sciences, Norwegian University of Life Sciences, As
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32
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Dilbirligi M, Erayman M, Campbell BT, Randhawa HS, Baenziger PS, Dweikat I, Gill KS. High-density mapping and comparative analysis of agronomically important traits on wheat chromosome 3A. Genomics 2006; 88:74-87. [PMID: 16624516 DOI: 10.1016/j.ygeno.2006.02.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2005] [Revised: 01/13/2006] [Accepted: 02/05/2006] [Indexed: 11/27/2022]
Abstract
Bread wheat chromosome 3A has been shown to contain genes/QTLs controlling grain yield and other agronomic traits. The objectives of this study were to generate high-density physical and genetic-linkage maps of wheat homoeologous group 3 chromosomes and reveal the physical locations of genes/QTLs controlling yield and its component traits, as well as agronomic traits, to obtain a precise estimate of recombination for the corresponding regions and to enrich the QTL-containing regions with markers. Physical mapping was accomplished by 179 DNA markers mostly representing expressed genes using 41 single-break deletion lines. Polymorphism survey of cultivars Cheyenne (CNN) and Wichita (WI), and a substitution line of CNN carrying chromosome 3A from WI [CNN(WI3A)], with 142 RFLP probes and 55 SSR markers revealed that the extent of polymorphism is different among various group 3 chromosomal regions as well as among the homoeologs. A genetic-linkage map for chromosome 3A was developed by mapping 17 QTLs for seven agronomic traits relative to 26 RFLP and 15 SSR chromosome 3A-specific markers on 95 single-chromosome recombinant inbred lines. Comparison of the physical maps with the 3A genetic-linkage map localized the QTLs to gene-containing regions and accounted for only about 36% of the chromosome. Two chromosomal regions containing 9 of the 17 QTLs encompassed less than 10% of chromosome 3A but accounted for almost all of the arm recombination. To identify rice chromosomal regions corresponding to the particular QTL-containing wheat regions, 650 physically mapped wheat group 3 sequences were compared with rice genomic sequences. At an E value of E < or = 10(-5), 82% of the wheat group 3 sequences identified rice homologs, of which 54% were on rice chromosome 1. The rice chromosome 1 region collinear with the two wheat regions that contained 9 QTLs was about 6.5 Mb.
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Affiliation(s)
- Muharrem Dilbirligi
- Crop and Soil Science Department, Washington State University, P.O. Box 646420, 277 Johnson Hall, Pullman, WA 99164, USA
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Ceoloni C, Jauhar P. Chromosome Engineering of the Durum Wheat Genome. GENETIC RESOURCES, CHROMOSOME ENGINEERING, AND CROP IMPROVEMENT 2006. [DOI: 10.1201/9780203489260.ch2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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34
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Vitte C, Panaud O. LTR retrotransposons and flowering plant genome size: emergence of the increase/decrease model. Cytogenet Genome Res 2005; 110:91-107. [PMID: 16093661 DOI: 10.1159/000084941] [Citation(s) in RCA: 180] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2003] [Accepted: 04/14/2004] [Indexed: 12/11/2022] Open
Abstract
Long Terminal Repeat (LTR) retrotransposons are ubiquitous components of plant genomes. Because of their copy-and-paste mode of transposition, these elements tend to increase their copy number while they are active. In addition, it is now well established that the differences in genome size observed in the plant kingdom are accompanied by variations in LTR retrotransposon content, suggesting that LTR retrotransposons might be important players in the evolution of plant genome size, along with polyploidy. The recent availability of large genomic sequences for many crop species has made it possible to examine in detail how LTR retrotransposons actually drive genomic changes in plants. In the present paper, we provide a review of the recent publications that have contributed to the knowledge of plant LTR retrotransposons, as structural components of the genomes, as well as from an evolutionary genomic perspective. These studies have shown that plant genomes undergo genome size increases through bursts of retrotransposition, while there is a counteracting process that tends to eliminate the transposed copies from the genomes. This process involves recombination mechanisms that occur either between the LTRs of the elements, leading to the formation of solo-LTRs, or between direct repeats anywhere in the sequence of the element, leading to internal deletions. All these studies have led to the emergence of a new model for plant genome evolution that takes into account both genome size increases (through retrotransposition) and decreases (through solo-LTR and deletion formation). In the conclusion, we discuss this new model and present the future prospects in the study of plant genome evolution in relation to the activity of transposable elements.
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Affiliation(s)
- C Vitte
- Laboratoire Ecologie, Systématique et Evolution, Université Paris-Sud, Orsay, France
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Gupta PK, Kulwal PL, Rustgi S. Wheat cytogenetics in the genomics era and its relevance to breeding. Cytogenet Genome Res 2005; 109:315-27. [PMID: 15753592 DOI: 10.1159/000082415] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2004] [Accepted: 05/11/2004] [Indexed: 01/26/2023] Open
Abstract
Hexaploid wheat is a species that has been subjected to most extensive cytogenetic studies. This has contributed to understanding the mechanism of the evolution of polyploids involving diploidization through genetic restriction of chromosome pairing to only homologous chromosomes. The availability of a variety of aneuploids and the ph mutants (Ph1 and Ph2) in bread wheat also allowed chromosome manipulations leading to the development of alien addition/substitution lines and the introgression of alien chromosome segments into the wheat genome. More recently in the genomics era, molecular tools have been used extensively not only for the construction of molecular maps, but also for identification/isolation of genes/QTLs (including epistatic QTLs, eQTLs and PQLs) for several agronomic traits. It has also been possible to identify gene-rich regions and recombination hot spots in the wheat genome, which are now being subjected to sequencing at the genome level, through development of BAC libraries. In the EST database also, among all plants wheat ESTs are the highest in number, and are only next to those for human, mouse, Ciona intestinalis (a chordate), rat and zebrafish genomes. These ESTs and sequences of several genomic regions have been subjected to a variety of applications including development of perfect markers and establishment of microcollinearity. The technique of in situ hybridization (including FISH, GISH and McFISH) and the development of deletion stocks also facilitated the preparation of physical maps. Molecular markers are also used for marker-assisted selection in wheat breeding programs in several countries. Construction of a wheat DNA chip, which will also become available soon, may further facilitate wheat genomics research. These enormous resources, knowledge base and the fast development of additional molecular tools and high throughput approaches for genotyping will prove extremely useful in future wheat research and will lead to development of improved wheat cultivars.
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Affiliation(s)
- P K Gupta
- Department of Genetics & Plant Breeding, Ch. Charan Singh University, Meerut, India.
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36
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Zhang LY, Bernard M, Leroy P, Feuillet C, Sourdille P. High transferability of bread wheat EST-derived SSRs to other cereals. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2005; 111:677-87. [PMID: 16034582 DOI: 10.1007/s00122-005-2041-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2005] [Accepted: 04/14/2005] [Indexed: 05/03/2023]
Abstract
The increasing availability of expressed sequence tags (ESTs) in wheat (Triticum aestivum) and related cereals provides a valuable resource of non-anonymous DNA molecular markers. In this study, 300 primer pairs were designed from 265 wheat ESTs that contain microsatellites in order to develop new markers for wheat. Their level of transferability in eight related species [Triticum durum, T. monococcum, Aegilops speltoides, Ae. tauschii, rye (Secale cereale), barley (Hordeum vulgare), Agropyron elongatum and rice (Oryza sativa)] was assessed. In total, 240 primer pairs (80%) gave an amplification product on wheat, and 177 were assigned to wheat chromosomes using aneuploid lines. Transferability to closely related Triticeae species ranged from 76.7% for Ae. tauschii to 90.4% for T. durum and was lower for more distant relatives such as barley (50.4%) or rice (28.3%). No clear putative function could be assigned to the genes from which the simple sequence repeats (SSRs) were developed, even though most of them were located inside ORFs. BLAST: analysis of the EST sequences against the 12 rice pseudo-molecules showed that the EST-SSRs are mainly located in the telomeric regions and that the wheat ESTs have the highest similarity to genes on rice chromosomes 2, 3 and 5. Interestingly, most of the SSRs giving an amplification product on barley or rice had a repeated motif similar to the one found in wheat, suggesting a common ancestral origin. Our results indicate that wheat EST-SSRs show a high level of transferability across distantly related species, thereby providing additional markers for comparative mapping and for following gene introgressions from wild species and carrying out evolutionary studies.
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Affiliation(s)
- L Y Zhang
- UMR INRA-UBP Amélioration et Santé des Plantes, 234 Avenue du Brézet, 63100 Domaine de Crouël, Clermont-Ferrand Cedex 2, France.
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37
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Qi L, Friebe B, Gill BS. Origin, structure, and behavior of a highly rearranged deletion chromosome 1BS-4 in wheat. Genome 2005; 48:591-7. [PMID: 16094425 DOI: 10.1139/g05-020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Wheat (Triticum aestivum L.) deletion (del) stocks are valuable tools for the physical mapping of molecular markers and genes to chromosome bins delineated by 2 adjacent deletion breakpoints. The wheat deletion stocks were produced by using gametocidal genes derived from related Aegilops species. Here, we report on the origin, structure, and behavior of a highly rearranged chromosome 1BS-4. The cytogenetic and molecular marker analyses suggest that 1BS-4 resulted from 2 breakpoints in the 1BS arm and 1 breakpoint in the 1BL arm. The distal segment from 1BS, except for a small deleted part, is translocated to the long arm. Cytologically, chromosome 1BS-4 is highly stable, but shows a unique meiotic pairing behavior. The short arm of 1BS-4 fails to pair with a normal 1BS arm because of lack of homology at the distal ends. The long arm of 1BS-4 only pairs with a normal 1BS arm within the distal region translocated from 1BS. Therefore, using the 1BS-4 deletion stock for physical mapping will result in the false allocation of molecular markers and genes proximal to the breakpoint of 1BS-4.Key words: Triticum aestivum, wheat, deletion–translocation, physical mapping.
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Affiliation(s)
- Lili Qi
- Wheat Genetics Resource Center, Department of Plant Pathology, Throckmorton Plant Sciences Center, Kansas State University, Manhattan, 66506, USA
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38
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Kulshreshtha R, Kumar N, Balyan HS, Gupta PK, Khurana P, Tyagi AK, Khurana JP. Structural characterization, expression analysis and evolution of the red/far-red sensing photoreceptor gene, phytochrome C (PHYC), localized on the 'B' genome of hexaploid wheat (Triticum aestivum L.). PLANTA 2005; 221:675-89. [PMID: 15891901 DOI: 10.1007/s00425-004-1473-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2004] [Accepted: 12/07/2004] [Indexed: 05/02/2023]
Abstract
Phytochromes are a family of red/far-red light perceiving photoreceptors. The monocot phytochrome family is represented by three members, PHYA, PHYB and PHYC. We have isolated and characterized the first PHY gene member (TaPHYC) from common wheat, Triticum aestivum var. CPAN1676. It codes for a species of the photoreceptor, phyC, which is known to be light-stable in all plants analyzed so far. A sequence of 7.2 kb has been determined, which includes 3.42 kb of coding region. This is the second full-length PHYC gene sequenced from a monocot (first was from rice). TaPHYC gene shares structural similarities with the rice PHYC containing four exons and three introns in the coding region. The 5' UTR is 1.0-kb-long and harbors an upstream open reading frame (URF) encoding 28 aa. Southern blot analysis of TaPHYC indicates that it represents single locus in the wheat genome, although the possibility of additional loci cannot be completely ruled out. Chromosomal localization using nullisomic-tetrasomic lines of Triticum aestivum var. Chinese Spring places TaPHYC on chromosome 4B. PHYC represents a constitutively expressed gene in all the organs tested and under light/dark conditions. However, PHYC was found to be developmentally regulated showing maximal expression in 3-day-old dark-grown seedlings, which declined thereafter. In silico analysis has also been done to compare TaPHYC gene with the partial sequences known from other wheat species and cultivars. The presence of a topoisomerase gene immediately downstream of the PHYC gene, both in rice and wheat genomes, presents yet another example of synteny in cereals and its possible significance has been discussed.
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Affiliation(s)
- R Kulshreshtha
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, 110 021, India
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39
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Dilbirligi M, Erayman M, Gill KS. Analysis of recombination and gene distribution in the 2L1.0 region of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). Genomics 2005; 86:47-54. [PMID: 15953539 DOI: 10.1016/j.ygeno.2005.03.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2005] [Revised: 03/05/2005] [Accepted: 03/21/2005] [Indexed: 01/20/2023]
Abstract
Both wheat and barley belong to tribe Triticeae and are closely related. High-density detailed comparison of physical and genetic linkage maps revealed that wheat genes are present in physically small gene-rich regions (GRRs). One of the largest GRRs is located around fraction length 1.0 of the long arm of wheat homoeologous group 2 chromosomes termed the "2L1.0 region." The main objective of this study was to analyze the structural and functional organization of the 2L1.0 region in barley in comparison to wheat. Using the 29 physically mapped RFLP markers for the region, wheat and barley consensus genetic linkage maps of the 2L1.0 region were generated by combining information from 18 wheat and 7 barley genetic linkage maps. Comparative analysis using these consensus maps and other available wheat and barley mapping resources identified 227 DNA markers and ESTs for the region. The region accounted for 58% of the genes and 68% of the arm's recombination in wheat. However, the corresponding region in barley accounted for about 42% of the genes and 81% of the recombination. The kb/cM ratio for the region was 122 in barley compared to 244 in wheat. Distribution of genes and recombination varied between the two species even though the gene order and density were similar.
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Affiliation(s)
- Muharrem Dilbirligi
- Central Research Institute for Field Crops, Pk 226, 0642 Ulus/Ankara, Turkey.
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40
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Hossain KG, Riera-Lizarazu O, Kalavacharla V, Vales MI, Maan SS, Kianian SF. Radiation hybrid mapping of the species cytoplasm-specific (scsae) gene in wheat. Genetics 2005; 168:415-23. [PMID: 15454553 PMCID: PMC1448084 DOI: 10.1534/genetics.103.022590] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Radiation hybrid (RH) mapping is based on radiation-induced chromosome breakage and analysis of chromosome segment retention or loss using molecular markers. In durum wheat (Triticum turgidum L., AABB), an alloplasmic durum line [(lo) durum] has been identified with chromosome 1D of T. aestivum L. (AABBDD) carrying the species cytoplasm-specific (scsae) gene. The chromosome 1D of this line segregates as a whole without recombination, precluding the use of conventional genome mapping. A radiation hybrid mapping population was developed from a hemizygous (lo) scsae--line using 35 krad gamma rays. The analysis of 87 individuals of this population with 39 molecular markers mapped on chromosome 1D revealed 88 radiation-induced breaks in this chromosome. This number of chromosome 1D breaks is eight times higher than the number of previously identified breaks and should result in a 10-fold increase in mapping resolution compared to what was previously possible. The analysis of molecular marker retention in our radiation hybrid mapping panel allowed the localization of scsae and 8 linked markers on the long arm of chromosome 1D. This constitutes the first report of using RH mapping to localize a gene in wheat and illustrates that this approach is feasible in a species with a large complex genome.
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Affiliation(s)
- Khwaja G Hossain
- Department of Plant Sciences, North Dakota State University, Fargo 58105, USA
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41
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Randhawa HS, Dilbirligi M, Sidhu D, Erayman M, Sandhu D, Bondareva S, Chao S, Lazo GR, Anderson OD, Gustafson JP, Echalier B, Qi LL, Gill BS, Akhunov ED, Dvorák J, Linkiewicz AM, Ratnasiri A, Dubcovsky J, Bermudez-Kandianis CE, Greene RA, Sorrells ME, Conley EJ, Anderson JA, Peng JH, Lapitan NLV, Hossain KG, Kalavacharla V, Kianian SF, Pathan MS, Nguyen HT, Endo TR, Close TJ, McGuire PE, Qualset CO, Gill KS. Deletion mapping of homoeologous group 6-specific wheat expressed sequence tags. Genetics 2005; 168:677-86. [PMID: 15514044 PMCID: PMC1448826 DOI: 10.1534/genetics.104.034843] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
To localize wheat (Triticum aestivum L.) ESTs on chromosomes, 882 homoeologous group 6-specific ESTs were identified by physically mapping 7965 singletons from 37 cDNA libraries on 146 chromosome, arm, and sub-arm aneuploid and deletion stocks. The 882 ESTs were physically mapped to 25 regions (bins) flanked by 23 deletion breakpoints. Of the 5154 restriction fragments detected by 882 ESTs, 2043 (loci) were localized to group 6 chromosomes and 806 were mapped on other chromosome groups. The number of loci mapped was greatest on chromosome 6B and least on 6D. The 264 ESTs that detected orthologous loci on all three homoeologs using one restriction enzyme were used to construct a consensus physical map. The physical distribution of ESTs was uneven on chromosomes with a tendency toward higher densities in the distal halves of chromosome arms. About 43% of the wheat group 6 ESTs identified rice homologs upon comparisons of genome sequences. Fifty-eight percent of these ESTs were present on rice chromosome 2 and the remaining were on other rice chromosomes. Even within the group 6 bins, rice chromosomal blocks identified by 1-6 wheat ESTs were homologous to up to 11 rice chromosomes. These rice-block contigs were used to resolve the order of wheat ESTs within each bin.
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Affiliation(s)
- H S Randhawa
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164-6420, USA
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42
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Linkiewicz AM, Qi LL, Gill BS, Ratnasiri A, Echalier B, Chao S, Lazo GR, Hummel DD, Anderson OD, Akhunov ED, Dvorák J, Pathan MS, Nguyen HT, Peng JH, Lapitan NLV, Gustafson JP, La Rota CM, Sorrells ME, Hossain KG, Kalavacharla V, Kianian SF, Sandhu D, Bondareva SN, Gill KS, Conley EJ, Anderson JA, Fenton RD, Close TJ, McGuire PE, Qualset CO, Dubcovsky J. A 2500-locus bin map of wheat homoeologous group 5 provides insights on gene distribution and colinearity with rice. Genetics 2005; 168:665-76. [PMID: 15514043 PMCID: PMC1448825 DOI: 10.1534/genetics.104.034835] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We constructed high-density deletion bin maps of wheat chromosomes 5A, 5B, and 5D, including 2338 loci mapped with 1052 EST probes and 217 previously mapped loci (total 2555 loci). This information was combined to construct a consensus chromosome bin map of group 5 including 24 bins. A relatively higher number of loci were mapped on chromosome 5B (38%) compared to 5A (34%) and 5D (28%). Differences in the levels of polymorphism among the three chromosomes were partially responsible for these differences. A higher number of duplicated loci was found on chromosome 5B (42%). Three times more loci were mapped on the long arms than on the short arms, and a significantly higher number of probes, loci, and duplicated loci were mapped on the distal halves than on the proximal halves of the chromosome arms. Good overall colinearity was observed among the three homoeologous group 5 chromosomes, except for the previously known 5AL/4AL translocation and a putative small pericentric inversion in chromosome 5A. Statistically significant colinearity was observed between low-copy-number ESTs from wheat homoeologous group 5 and rice chromosomes 12 (88 ESTs), 9 (72 ESTs), and 3 (84 ESTs).
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Affiliation(s)
- A M Linkiewicz
- Department of Agronomy and Range Science, University of California, Davis, California 95616, USA
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43
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Qi LL, Echalier B, Chao S, Lazo GR, Butler GE, Anderson OD, Akhunov ED, Dvorák J, Linkiewicz AM, Ratnasiri A, Dubcovsky J, Bermudez-Kandianis CE, Greene RA, Kantety R, La Rota CM, Munkvold JD, Sorrells SF, Sorrells ME, Dilbirligi M, Sidhu D, Erayman M, Randhawa HS, Sandhu D, Bondareva SN, Gill KS, Mahmoud AA, Ma XF, Gustafson JP, Conley EJ, Nduati V, Gonzalez-Hernandez JL, Anderson JA, Peng JH, Lapitan NLV, Hossain KG, Kalavacharla V, Kianian SF, Pathan MS, Zhang DS, Nguyen HT, Choi DW, Fenton RD, Close TJ, McGuire PE, Qualset CO, Gill BS. A chromosome bin map of 16,000 expressed sequence tag loci and distribution of genes among the three genomes of polyploid wheat. Genetics 2005; 168:701-12. [PMID: 15514046 PMCID: PMC1448828 DOI: 10.1534/genetics.104.034868] [Citation(s) in RCA: 348] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Because of the huge size of the common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) genome of 17,300 Mb, sequencing and mapping of the expressed portion is a logical first step for gene discovery. Here we report mapping of 7104 expressed sequence tag (EST) unigenes by Southern hybridization into a chromosome bin map using a set of wheat aneuploids and deletion stocks. Each EST detected a mean of 4.8 restriction fragments and 2.8 loci. More loci were mapped in the B genome (5774) than in the A (5173) or D (5146) genomes. The EST density was significantly higher for the D genome than for the A or B. In general, EST density increased relative to the physical distance from the centromere. The majority of EST-dense regions are in the distal parts of chromosomes. Most of the agronomically important genes are located in EST-dense regions. The chromosome bin map of ESTs is a unique resource for SNP analysis, comparative mapping, structural and functional analysis, and polyploid evolution, as well as providing a framework for constructing a sequence-ready, BAC-contig map of the wheat genome.
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Affiliation(s)
- L L Qi
- Department of Plant Pathology, Wheat Genetics Resource Center, Kansas State University, Manhattan, Kansas 66506-5502, USA
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44
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Mater Y, Baenziger S, Gill K, Graybosch R, Whitcher L, Baker C, Specht J, Dweikat I. Linkage mapping of powdery mildew and greenbug resistance genes on recombinant 1RS from 'Amigo' and 'Kavkaz' wheat-rye translocations of chromosome 1RS.1AL. Genome 2005; 47:292-8. [PMID: 15060581 DOI: 10.1139/g03-101] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cultivated rye (Secale cereale L., 2n = 2x = 14, RR) is an important source of genes for insect and disease resistance in wheat (Triticum aestivum L., 2n = 6x = 42). Rye chromosome arm 1RS of S. cereale 'Kavkaz' originally found as a 1BL.1RS translocation, carries genes for disease resistance (e.g., Lr26, Sr31, Yr9, and Pm8), while 1RS of the S. cereale 'Amigo' translocation (1RSA) carries a single resistance gene for greenbug (Schizaphis graminum Rondani) biotypes B and C and also carries additional disease-resistance genes. The purpose of this research was to identify individual plants that were recombinant in the homologous region of.1AL.1RSV and 1AL.1RSA using both molecular and phenotypic markers. Secale cereale 'Nekota' (1AL.1RSA) and S. cereale 'Pavon 76' (1AL.1RSV) were mated and the F1 was backcrossed to 'Nekota' (1AL.1AS) to generate eighty BC1F2:3 families (i.e., ('Nekota' 1AL.1RSA x 'Pavon 76' 1AL.1RSV) x 'Nekota' 1AL.1AS). These families were genotyped using the secalin-gliadin grain storage protein banding pattern generated with polyacrylamide gel electrophoresis to discriminate 1AL.1AS/1AL.1RS heterozygotes from the 1AL.1RSA+V and 1AL.1AS homozygotes. Segregation of the secalin locus and PCR markers based on the R173 family of rye specific repeated DNA sequences demonstrated the presence of recombinant 1AL.1RSA+V families. Powdery mildew (Blumeria graminis) and greenbug resistance genes on the recombinant 1RSA+V arm were mapped in relation to the Sec-1 locus, 2 additional protein bands, 3 SSRs, and 13 RFLP markers. The resultant linkage map of 1RS spanned 82.4 cM with marker order and spacing showing reasonable agreement with previous maps of 1RS. Fifteen markers lie within a region of 29.7 cM next to the centromere, yet corresponded to just 36% of the overall map length. The map position of the RFLP marker probe mwg68 was 10.9 cM distal to the Sec-1 locus and 7.8 cM proximal to the powdery mildew resistance locus. The greenbug resistance gene was located 2.7 cM proximal to the Sec-1 locus.
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Affiliation(s)
- Yehia Mater
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln 68583, USA
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45
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Khrustaleva LI, de Melo PE, van Heusden AW, Kik C. The integration of recombination and physical maps in a large-genome monocot using haploid genome analysis in a trihybrid allium population. Genetics 2005; 169:1673-85. [PMID: 15654085 PMCID: PMC1449564 DOI: 10.1534/genetics.104.038687] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Integrated mapping in large-genome monocots has been carried out on a limited number of species. Furthermore, integrated maps are difficult to construct for these species due to, among other reasons, the specific plant populations needed. To fill these gaps, Alliums were chosen as target species and a new strategy for constructing suitable populations was developed. This strategy involves the use of trihybrid genotypes in which only one homeolog of a chromosome pair is recombinant due to interspecific recombination. We used genotypes from a trihybrid Allium cepa x (A. roylei x A. fistulosum) population. Recombinant chromosomes 5 and 8 from the interspecific parent were analyzed using genomic in situ hybridization visualization of recombination points and the physical positions of recombination were integrated into AFLP linkage maps of both chromosomes. The integrated maps showed that in Alliums recombination predominantly occurs in the proximal half of chromosome arms and that 57.9% of PstI/MseI markers are located in close proximity to the centromeric region, suggesting the presence of genes in this region. These findings are different from data obtained on cereals, where recombination rate and gene density tends to be higher in distal regions.
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Affiliation(s)
- L I Khrustaleva
- Plant Research International, Wageningen University and Research Center, The Netherlands
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46
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Hossain KG, Kalavacharla V, Lazo GR, Hegstad J, Wentz MJ, Kianian PMA, Simons K, Gehlhar S, Rust JL, Syamala RR, Obeori K, Bhamidimarri S, Karunadharma P, Chao S, Anderson OD, Qi LL, Echalier B, Gill BS, Linkiewicz AM, Ratnasiri A, Dubcovsky J, Akhunov ED, Dvorák J, Miftahudin, Ross K, Gustafson JP, Radhawa HS, Dilbirligi M, Gill KS, Peng JH, Lapitan NLV, Greene RA, Bermudez-Kandianis CE, Sorrells ME, Feril O, Pathan MS, Nguyen HT, Gonzalez-Hernandez JL, Conley EJ, Anderson JA, Choi DW, Fenton D, Close TJ, McGuire PE, Qualset CO, Kianian SF. A chromosome bin map of 2148 expressed sequence tag loci of wheat homoeologous group 7. Genetics 2004; 168:687-99. [PMID: 15514045 PMCID: PMC1448827 DOI: 10.1534/genetics.104.034850] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2003] [Accepted: 06/01/2004] [Indexed: 01/16/2023] Open
Abstract
The objectives of this study were to develop a high-density chromosome bin map of homoeologous group 7 in hexaploid wheat (Triticum aestivum L.), to identify gene distribution in these chromosomes, and to perform comparative studies of wheat with rice and barley. We mapped 2148 loci from 919 EST clones onto group 7 chromosomes of wheat. In the majority of cases the numbers of loci were significantly lower in the centromeric regions and tended to increase in the distal regions. The level of duplicated loci in this group was 24% with most of these loci being localized toward the distal regions. One hundred nineteen EST probes that hybridized to three fragments and mapped to the three group 7 chromosomes were designated landmark probes and were used to construct a consensus homoeologous group 7 map. An additional 49 probes that mapped to 7AS, 7DS, and the ancestral translocated segment involving 7BS also were designated landmarks. Landmark probe orders and comparative maps of wheat, rice, and barley were produced on the basis of corresponding rice BAC/PAC and genetic markers that mapped on chromosomes 6 and 8 of rice. Identification of landmark ESTs and development of consensus maps may provide a framework of conserved coding regions predating the evolution of wheat genomes.
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Affiliation(s)
- K G Hossain
- Department of Plant Sciences, North Dakota State University, Fargo, North Dakota 58105, USA
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47
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Peng JH, Zadeh H, Lazo GR, Gustafson JP, Chao S, Anderson OD, Qi LL, Echalier B, Gill BS, Dilbirligi M, Sandhu D, Gill KS, Greene RA, Sorrells ME, Akhunov ED, Dvorák J, Linkiewicz AM, Dubcovsky J, Hossain KG, Kalavacharla V, Kianian SF, Mahmoud AA, Miftahudin, Conley EJ, Anderson JA, Pathan MS, Nguyen HT, McGuire PE, Qualset CO, Lapitan NLV. Chromosome bin map of expressed sequence tags in homoeologous group 1 of hexaploid wheat and homoeology with rice and Arabidopsis. Genetics 2004; 168:609-23. [PMID: 15514039 PMCID: PMC1448821 DOI: 10.1534/genetics.104.034793] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2003] [Accepted: 06/01/2004] [Indexed: 11/18/2022] Open
Abstract
A total of 944 expressed sequence tags (ESTs) generated 2212 EST loci mapped to homoeologous group 1 chromosomes in hexaploid wheat (Triticum aestivum L.). EST deletion maps and the consensus map of group 1 chromosomes were constructed to show EST distribution. EST loci were unevenly distributed among chromosomes 1A, 1B, and 1D with 660, 826, and 726, respectively. The number of EST loci was greater on the long arms than on the short arms for all three chromosomes. The distribution of ESTs along chromosome arms was nonrandom with EST clusters occurring in the distal regions of short arms and middle regions of long arms. Duplications of group 1 ESTs in other homoeologous groups occurred at a rate of 35.5%. Seventy-five percent of wheat chromosome 1 ESTs had significant matches with rice sequences (E < or = e(-10)), where large regions of conservation occurred between wheat consensus chromosome 1 and rice chromosome 5 and between the proximal portion of the long arm of wheat consensus chromosome 1 and rice chromosome 10. Only 9.5% of group 1 ESTs showed significant matches to Arabidopsis genome sequences. The results presented are useful for gene mapping and evolutionary and comparative genomics of grasses.
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Affiliation(s)
- J H Peng
- Department of Soil and Crop Sciences, Colorado State University, Fort Collins, Colorado 80523-1170, USA
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48
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Gill BS, Appels R, Botha-Oberholster AM, Buell CR, Bennetzen JL, Chalhoub B, Chumley F, Dvorák J, Iwanaga M, Keller B, Li W, McCombie WR, Ogihara Y, Quetier F, Sasaki T. A workshop report on wheat genome sequencing: International Genome Research on Wheat Consortium. Genetics 2004; 168:1087-96. [PMID: 15514080 PMCID: PMC1448818 DOI: 10.1534/genetics.104.034769] [Citation(s) in RCA: 177] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Sponsored by the National Science Foundation and the U.S. Department of Agriculture, a wheat genome sequencing workshop was held November 10-11, 2003, in Washington, DC. It brought together 63 scientists of diverse research interests and institutions, including 45 from the United States and 18 from a dozen foreign countries (see list of participants at http://www.ksu.edu/igrow). The objectives of the workshop were to discuss the status of wheat genomics, obtain feedback from ongoing genome sequencing projects, and develop strategies for sequencing the wheat genome. The purpose of this report is to convey the information discussed at the workshop and provide the basis for an ongoing dialogue, bringing forth comments and suggestions from the genetics community.
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Affiliation(s)
- Bikram S Gill
- Plant Pathology Department, Kansas State University, Manhattan, Kansas 66506-5502, USA.
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49
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Liu ZH, Faris JD, Meinhardt SW, Ali S, Rasmussen JB, Friesen TL. Genetic and Physical Mapping of a Gene Conditioning Sensitivity in Wheat to a Partially Purified Host-Selective Toxin Produced by Stagonospora nodorum. PHYTOPATHOLOGY 2004; 94:1056-60. [PMID: 18943793 DOI: 10.1094/phyto.2004.94.10.1056] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
ABSTRACT A toxin, designated SnTox1, was partially purified from culture filtrates of isolate Sn2000 of Stagonospora nodorum, the causal agent of wheat leaf and glume blotch. The toxin showed selective action on several different wheat genotypes, indicating that it is a host-selective toxin (HST). The toxic activity was reduced when incubated at 50 degrees C and activity was eliminated when treated with proteinase K, suggesting that the HST is a protein. The synthetic hexaploid wheat W-7984 and hard red spring wheat Opata 85, the parents of the International Triticeae Mapping Initiative (ITMI) mapping population, were found to be sensitive and insensitive, respectively, to SnTox1. The ITMI mapping population was evaluated for toxin reaction and used to map the gene conditioning sensitivity. This gene, designated Snn1, mapped to the distal end of the short arm of chromosome 1B. The wheat cv. Chinese Spring (CS) and all CS nullisomic-tetrasomic lines were sensitive to the toxin, with the exception of N1BT1D. Insensitivity also was observed when the 1B chromosome of CS was substituted with the 1B chromosome of an insensitive accession of Triticum dicoccoides. In addition, a series of 1BS chromosome deletion lines were used to physically localize the sensitivity gene. Physical mapping indicated that Snn1 lies within a major gene-rich region on 1BS. This is the first report identifying a putative proteinaceous HST from S. nodorum and the chromosomal location of a host gene conferring sensitivity.
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Conley EJ, Nduati V, Gonzalez-Hernandez JL, Mesfin A, Trudeau-Spanjers M, Chao S, Lazo GR, Hummel DD, Anderson OD, Qi LL, Gill BS, Echalier B, Linkiewicz AM, Dubcovsky J, Akhunov ED, Dvorák J, Peng JH, Lapitan NLV, Pathan MS, Nguyen HT, Ma XF, Miftahudin, Gustafson JP, Greene RA, Sorrells ME, Hossain KG, Kalavacharla V, Kianian SF, Sidhu D, Dilbirligi M, Gill KS, Choi DW, Fenton RD, Close TJ, McGuire PE, Qualset CO, Anderson JA. A 2600-locus chromosome bin map of wheat homoeologous group 2 reveals interstitial gene-rich islands and colinearity with rice. Genetics 2004; 168:625-37. [PMID: 15514040 PMCID: PMC1448822 DOI: 10.1534/genetics.104.034801] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2003] [Accepted: 06/01/2004] [Indexed: 11/18/2022] Open
Abstract
The complex hexaploid wheat genome offers many challenges for genomics research. Expressed sequence tags facilitate the analysis of gene-coding regions and provide a rich source of molecular markers for mapping and comparison with model organisms. The objectives of this study were to construct a high-density EST chromosome bin map of wheat homoeologous group 2 chromosomes to determine the distribution of ESTs, construct a consensus map of group 2 ESTs, investigate synteny, examine patterns of duplication, and assess the colinearity with rice of ESTs assigned to the group 2 consensus bin map. A total of 2600 loci generated from 1110 ESTs were mapped to group 2 chromosomes by Southern hybridization onto wheat aneuploid chromosome and deletion stocks. A consensus map was constructed of 552 ESTs mapping to more than one group 2 chromosome. Regions of high gene density in distal bins and low gene density in proximal bins were found. Two interstitial gene-rich islands flanked by relatively gene-poor regions on both the short and long arms and having good synteny with rice were discovered. The map locations of two ESTs indicated the possible presence of a small pericentric inversion on chromosome 2B. Wheat chromosome group 2 was shown to share syntenous blocks with rice chromosomes 4 and 7.
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Affiliation(s)
- E J Conley
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, Minnesota 55108, USA
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