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STS Markers (sts + marker)

Distribution by Scientific Domains
Life Sciences100%

Selected Abstracts

Comparison of a modified assay method for the endopeptidase marker Ep-D1b with the Sequence Tag Site marker XustSSR2001,7DL for strawbreaker foot rot resistance in wheat

PLANT BREEDING, Issue 1 2006
D. K. Santra
Abstract The endopeptidase marker Ep-D1b and Sequence Tag Site (STS) marker XustSSR2001,7DL were reported to be closely associated with the most effective resistance gene (Pch1) in wheat (Triticum aestivum L.) for strawbreaker foot rot [Pseudocercosporella herpotrichoides (Fron) Deighton]. Our objectives were to: (i) develop an efficient assay method for Ep-D1b in wheat; (ii) correlate endopeptidase zymograms to strawbreaker foot rot reactions of various wheat genotypes; and (iii) compare the utility of Ep-D1b and XustSSR2001,7DL for predicting disease response. An improved method of assaying for the Ep-D1b marker using roots from a single seedling was developed, which is a 2.5-fold improvement over the previous method. Thirty-eight wheat genotypes with known reactions to strawbreaker foot rot were analysed for Ep-D1b and the STS marker. Six distinct endopeptidase zymograms were identified among these 38 genotypes tested, and three of these patterns were novel. The endopeptidase marker was 100% accurate for predicting strawbreaker foot rot disease response, whereas the STS marker predicted the correct phenotype with approximately 90% accuracy. The endopeptidase marker Ep-D1b was more effective and was more economical for use in marker-assisted selection strategies for Pch1 in our laboratory compared with the STS marker. [source]

An STS marker distinguishing the rye-derived powdery mildew resistance alleles at the Pm8/Pm17 locus of common wheat

PLANT BREEDING, Issue 5 2001
V. Mohler
Abstract A sequence-tagged site marker has been developed from restriction fragment length polymorphism marker probe IAG95 for the rye-derived powdery mildew resistance Pm8/Pm17 locus of common wheat. This polymerase chain reaction marker enables the amplification of DNA fragments with different sizes from T1AL.1RS and T1BL.1RS wheat-rye translocation cultivars with chromatin from ,Insave' and ,Petkus' rye, respectively, and therefore will be very useful in distinguishing Pm8 -carrying cultivars from Pm17 -carrying cultivars. Results obtained with that marker were compared with resistance tests performed on detached primary leaves of 29 wheat lines from two populations derived from doubled haploid production. The molecular assay corresponded well with the resistance tests in all the lines, and therefore will be helpful for the identification of Pm17 in lines in which other Pm genes or quantitative trait loci are present. [source]

Development of STS markers and QTL validation for common bacterial blight resistance in common bean

PLANT BREEDING, Issue 1 2008
S. Liu
Abstract Common bacterial blight (CBB) of common bean (Phaseolus vulgaris L.), is one of the major diseases that decrease yield and quality. A major quantitative trait locus (QTL) for CBB resistance from line XAN 159 was transferred into two bean lines, HR45 and HR67. Previous studies identified that two markers are linked to this QTL but the chromosome location was not consistent. To identify more tightly linked markers and to verify the chromosome location, 65 additional markers were mapped using 81 recombinant inbred lines (RILs) derived from a cross HR67 × OAC95-4. The QTL was mapped to a 13 cM region on chromosome 1 and defined by eight molecular markers that explained 25,52% of the phenotypic variation. Six tightly linked amplified fragment length polymorphism markers (0.6,9.7 cM from the QTL peak) were converted into seven sequence tagged site markers, three of which were mapped to this QTL. Five tightly linked markers were used to screen 907 F2 plants derived from a cross HR45 × ,OAC Rex' and four of them were linked to each other within 4.2 cM. These markers may be useful in marker-assisted selection and map-based cloning of this major QTL. [source]

Introgression of crown rust (Puccinia coronata) resistance from meadow fescue (Festuca pratensis) into Italian ryegrass (Lolium multiflorum): genetic mapping and identification of associated molecular markers

PLANT PATHOLOGY, Issue 1 2006
I. P. Armstead
Crown rust (Puccinia coronata) resistance (CRres), which had been introgressed from meadow fescue (Festuca pratensis) into the Italian ryegrass (Lolium multiflorum) background, was genetically mapped with amplified fragment length polymorphism (AFLP) and sequence tagged site (STS) markers to a terminal segment of chromosome 5. Comparative mapping had previously shown that this region of the Lolium/Festuca genome has a degree of conserved genetic synteny with chromosomes 11 and 12 of rice. Sequences from rice chromosome 12 were used as templates for identifying further STS markers that cosegregated with CRres. The relative genomic positions of molecular markers associated with CRres in L. multiflorum, L. perenne, F. pratensis and oats is discussed, along with their relationships to physical positions on rice chromosomes C11 and C12. [source]

A 2.5-Mb contig constructed from Angus, Longhorn and horned Hereford DNA spanning the polled interval on bovine chromosome 1

ANIMAL GENETICS, Issue 6 2006
K. R. Wunderlich
Summary The polled locus has been mapped by genetic linkage analysis to the proximal region of bovine chromosome 1. As an intermediate step in our efforts to identify the polled locus and the underlying causative mutation for the polled phenotype, we have constructed a BAC-based physical map of the interval containing the polled locus. Clones containing genes and markers in the critical interval were isolated from the TAMBT (constructed from Angus and Longhorn genomic DNA) and CHORI-240 (constructed from horned Hereford genomic DNA) BAC libraries and ordered based on fingerprinting and the presence or absence of 80 STS markers. A single contig spanning 2.5 Mb was assembled. Comparison of the physical order of STSs to the corresponding region of human chromosome 21 revealed the same order of genes within the polled critical interval. This contig of overlapping BAC clones from horned and polled breeds is a useful resource for SNP discovery and characterization of positional candidate genes. [source]

Molecular evidence for the hybrid origin of a new endemic species of Stylosanthes Sw. (Fabaceae) from the Mexican Yucatán Peninsula

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2002
JACQUELINE VANDER STAPPEN
Stylosanthes aff. calcicola is a formally undescribed tetraploid species from the Mexican Yucatán Peninsula, showing morphological similarities to the diploid species S. calcicola, but distinct in a number of characters. We used uni- and biparentally inherited molecular markers to infer the hybrid origin of this species in relation to known diploid species of Stylosanthes. Molecular characterization was based on length and/or DNA sequence variation of nuclear sequence-tagged site (STS) markers, the internal transcribed spacer (ITS) region of nuclear rDNA and the trnL intron of chloroplast DNA (cpDNA). Stylosanthes aff. calcicola contains a distinct cpDNA haplotype and nuclear DNA fragment, with closest relationship to the diploid species S. calcicola. In contrast, the DNA sequences of two nuclear loci reveal a closer relationship to the diploid species S. angustifolia, S. hispida, S. humilis, S. leiocarpa and S. viscosa. The majority of the STS markers showed additivity of PCR fragments in S. aff. calcicola, representing the combination of two genetically different genomes. We postulate that S. aff. calcicola is a distinct species of allotetraploid origin that appears to have originated once from hybridization between two divergent genomes, of which the maternal and paternal parent are closely related to, or derived from, a member of the lineages represented by S. calcicola and S. viscosa, respectively. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society, 140, 1,13. [source]