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Restorer Gene (restorer + gene)
Selected AbstractsMolecular mapping of a fertility restorer gene for cytoplasmic male sterility in soybeanPLANT BREEDING, Issue 1 2010Y. Wang With 2 figures and 2 tables Abstract In this study, we report the mapping of the Rf locus in soybean by microsatellite simple sequence repeat (SSR) genetic markers. A cross was made between cytoplasmic male sterility (CMS) line JLCMS82A and restorer line JIHUI 1 based on the DNA polymorphisms revealed by 109 SSR markers. A F2 population derived from a single F1 plant containing 103 individuals was used for mapping the Rf locus. The Rf gene of JIHUI 1 gametophytically restores male fertility to JLCMS82A. Fertile and semi-fertile DNA bulks and parental DNAs were screened with 219 SSR markers, and Satt215 which was previously mapped to soybean LG J, was found linked to the Rf gene. Five additional polymorphic SSR markers from LG J were used for analysis and a regional linkage map around the Rf locus was established. SSR markers, Sctt011 and Satt547, flanked the Rf locus at 3.6 cM and 5.4 cM, respectively. The availability of these SSR markers will facilitate the selection of restorer lines in hybrid soybean breeding. [source] Development and characterization of SCAR markers associated with a dominant genic male sterility in rapeseedPLANT BREEDING, Issue 1 2008D. 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] Transgenic rice hybrids that carry the Rf-1 gene at multiple loci show improved fertility at low temperaturePLANT CELL & ENVIRONMENT, Issue 4 2005TOSHIYUKI KOMORI ABSTRACT By using a genomic fragment that carries the rice (Oryza sativa L.) fertility restorer gene, Rf-1, rice restorer lines harbouring multiple Rf-1 genes on different chromosomes were developed by genetic engineering and crossing. Hybrid lines that were obtained by crossing the restorer lines having two and three Rf-1 genes with a cytoplasmic male sterile (CMS) line had nearly 75 and 87.5% pollen fertility rates under a normal condition, respectively, whereas a conventional hybrid line showed a 50% pollen fertility rate. Furthermore, the seed set percentage under low temperature conditions was much higher in the hybrid lines with multiple Rf-1 genes than the conventional hybrid line. These results indicate that multiplication of the Rf-1 gene conferred cold tolerance at the booting stage to hybrid rice through increasing the potentially fertile pollen grains. This strategy to improve fertility at low temperature of hybrids could be applied to any grain crops that are developed based on CMS and its gametophytic restorer gene, let alone rice. [source] DO RECENT FINDINGS IN PLANT MITOCHONDRIAL MOLECULAR AND POPULATION GENETICS HAVE IMPLICATIONS FOR THE STUDY OF GYNODIOECY AND CYTONUCLEAR CONFLICT?EVOLUTION, Issue 5 2008David E. McCauley The coexistence of females and hermaphrodites in plant populations, or gynodioecy, is a puzzle recognized by Darwin. Correns identified cytoplasmic inheritance of one component of sex expression, now known as cytoplasmic male sterility (CMS). Lewis established cytonuclear inheritance of gynodioecy as an example of genetic conflict. Although biologists have since developed an understanding of the mechanisms allowing the joint maintenance of CMS and nuclear male fertility restorer genes, puzzles remain concerning the inheritance of sex expression and mechanisms governing the origination of CMS. Much of the theory of gynodioecy rests on the assumption of maternal inheritance of the mitochondrial genome. Here we review recent studies of the genetics of plant mitochondria, and their implications for the evolution and transmission of CMS. New studies of intragenomic recombination provide a plausible origin for the chimeric ORFs that characterize CMS. Moreover, evidence suggests that nonmaternal inheritance of mitochondria may be more common than once believed. These findings may have consequences for the maintenance of cytonuclear polymorphism, mitochondrial recombination, generation of gynomonoecious phenotypes, and interpretation of experimental crosses. Finally we point out that CMS can alter the nature of the cytonuclear conflict that may have originally selected for uniparental inheritance. [source] Inheritance and gene tagging of male fertility restoration of cytoplasmic-nuclear male-sterile line NJCMS1A in soybeanPLANT BREEDING, Issue 3 2007S. P. Yang Abstract The F1, F2 and F2:3 of the NJCMS1A × ,Zhongdou 5' cross were used to analyse the inheritance of the male fertility restoration of the cytoplasmic-nuclear male-sterile line NJCMS1A in soybean. The results of genetic analysis showed two pairs of dominant genes conferring the male fertility restoration of NJCMS1A, which further confirmed previous results. The F2 population from the NJCMS1A × ,Zhongdou 5' cross was used for tagging the restorer genes for NJCMS1A with 664 pairs of simple sequence repeat primers selected randomly from the genetic linkage map of soybean published by Cregan et al. (1999). Satt626 on linkage group M and Satt300 on linkage group A1 of the integrated linkage map by Song et al. (2004) were found to link to the two restorer genes of NJCMS1A. The maximum-likelihood estimates of the genetic distance between the two markers, Satt626 and Satt300, and the two restorer genes of ,Zhongdou 5' were 9.75 and 11.18 cM, respectively. [source] |