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SCAR Markers (scar + marker)

Distribution by Scientific Domains

Life Sciences	100%

Selected Abstracts

Identification of a SCAR marker linked to a recessive male sterile gene (Tems) and its application in breeding of marigold (Tagetes erecta)

PLANT BREEDING, Issue 1 2009
Y. H. He
Abstract In marigold, an F2 segregation population of 167 plants was constructed from a cross of a line (M525A) carrying the male sterility trait × an inbred line (f53f). In line M525A, the male sterility trait was controlled by the recessive gene, Tems. The intersimple sequence repeat (ISSR) and sequence-related amplified polymorphism (SRAP) techniques combined with bulked segregant analysis were used to develop markers linked to the trait. From a survey of the 38 ISSR primers and 170 SRAP primer combinations, only one SRAP marker that was closely linked to the target trait was identified and successfully converted into sequence characterized amplified region (SCAR) marker that was located within 2.4 cM from Tems locus. The marker was validated with five other two-type lines and in each case the male fertile plants were reliably identified. This SCAR marker therefore permits the efficient marker-assisted selection of male sterile individuals in breeding programmes of marigold and will greatly facilitate the breeding of F1 cultivars. [source]

Development and characterization of SCAR markers associated with a dominant genic male sterility in rapeseed

PLANT BREEDING, Issue 1 2008
D. F. Hong
Abstract Rs1046AB is a dominant genic male sterility (DGMS) line in rapeseed, in which the sterility has always been thought to be conditioned by the interaction of a male sterility gene (Ms) and its non-allelic restorer gene (Rf). This system provides not only a tool for assisting in recurrent selection but also a promising system for hybrid production. Based on previous studies, two amplified fragment length polymorphism markers linked with the Ms gene were converted into a dominant and a co-dominant sequence characterized amplified region (SCAR) marker, respectively. The putative linear order relationship of three dominant SCAR markers with the same genetic distance from the Rf gene, was also determined by an examination of whether the homologues of these markers are present or not in different lines carrying Rf. A bigger fragment generated by the closest marker linked to the Rf gene was observed in all lines carrying the recessive allele rf, suggesting that this marker is a co-dominant marker, which was further confirmed by nucleotide sequence comparison of these fragments. SCAR markers specific for Ms and Rf will be especially valuable in marker-assisted DGMS three-line breeding. [source]

Development of SCAR markers for identification of stem rust resistance gene Sr31 in the homozygous or heterozygous condition in bread wheat

PLANT BREEDING, Issue 6 2006
B. K. Das
Abstract The stem rust resistance gene Sr31, transferred from rye (Secale cereale) into wheat (Triticum aestivum L.) imparts resistance to all the virulent pathotypes of stem rust (Puccinia graminis f. sp. tritici) found in India. Wheat genotypes including carriers and non-carriers of the Sr31 gene were analysed using arbitrary primed polymerase chain reaction (AP-PCR). AP-PCR markers viz. SS30.2580(H) associated with the Sr31 gene and SS26.11100 associated with the allele for susceptibility were identified. Linkage between the markers and phenotypes was confirmed by analysing an F2 population obtained from a cross between a resistant and a susceptible genotype. The markers were tightly linked to the respective alleles. Both the AP-PCR markers were converted into sequence characterized amplified region (SCAR) markers, viz. SCSS30.2576 and SCSS26.11100 respectively. The markers were validated in two more segregating populations and 49 wheat genotypes. Using both markers it was possible to distinguish the homozygous from the heterozygous carriers of the Sr31 gene in the F2 generation. The markers developed in this study can be used for pyramiding of the Sr31 gene with other rust resistance genes and in marker-assisted selection. [source]

Variation in the response of melon genotypes to Fusarium oxysporum f.sp. melonis race 1 determined by inoculation tests and molecular markers

PLANT PATHOLOGY, Issue 2 2003
Y. Burger
Screening of genotypes of melon (Cucumis melo) for resistance to wilt caused by Fusarium oxysporum f.sp. melonis is often characterized by wide variability in their responses to inoculation, even under carefully controlled conditions. The variability at the seedling stage of 17 genotypes susceptible to race 1 was examined in growth-chamber experiments. Disease incidence varied from 0 to 100% in a genotype-dependent manner. Using four combinations of light (60 and 90 µE m,2 s,1) and temperatures of (27 and 31°C), only light intensity showed a statistically significant effect. Marker-assisted selection for fusarium resistance breeding using cleaved amplified polymorphic sequence (CAPS) and sequence-characterized amplified region (SCAR) markers were compared using a single set of genotypes that included 24 melon accessions and breeding lines whose genotype regarding the Fom-2 gene was well characterized. The practical value of the markers for discriminating a range of genotypes and clarifying the scoring of phenotypes was also tested using a segregating breeding population which showed codominant SCAR markers to be useful in marker-assisted selection. [source]

Isolation of Y- and X-linked SCAR markers in yellow catfish and application in the production of all-male populations

ANIMAL GENETICS, Issue 6 2009
D. Wang
Summary Sex controls have been performed in some farmed fish species because of significant growth differences between females and males. In yellow catfish (Pelteobagrus fulvidraco), adult males are three times larger than female adults. In this study, six Y- and X-linked amplified fragment length polymorphism fragments were screened by sex-genotype pool bulked segregant analysis and individual screening. Interestingly, sequence analysis identified two pairs of allelic genes, Pf33 and Pf62. Furthermore, the cloned flanking sequences revealed several Y- and X-specific polymorphisms, and four Y-linked or X-linked sequence characterized amplified region (SCAR) primer pairs were designed and converted into Y- and X-linked SCAR markers. Consequently, these markers were successfully used to identify genetic sex and YY super-males, and applied to all-male population production. Thus, we developed a novel and simple technique to help commercial production of YY super-males and all-male populations in the yellow catfish. [source]