Submitted to: Theoretical and Applied Genetics
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/15/2005
Publication Date: 9/1/2005
Citation: Liu, Z., Anderson, J.A., Hu, J., Friesen, T.L., Rasmussen, J.B., Faris, J.D. 2005. A wheat intervarietal genetic linkage map based on microsatellite and target region amplified polymorphism markers and its utility for detecting quantitative trait loci. Theoretical and Applied Genetics. Vol. 111:792-794. Interpretive Summary: Molecular markers are useful for developing maps of chromosomes and can be employed to identify chromosomal regions containing genes that govern important traits. Various types of molecular marker techniques exist, but the most useful are those that are user-friendly and can efficiently generate a large number of markers rapidly with minimal input. The target region amplified polymorphism (TRAP) technique was recently developed and meets these criteria. In this work, we used TRAPS in combination with other marker techniques to develop genetic maps in a hard red spring wheat population. Over 700 markers were developed and used for mapping. We used the maps to identify regions of chromosomes harboring genes that govern plant height and days-to-heading in the population.
Technical Abstract: Efficient user-friendly methods for mapping plant genomes are highly desirable for the identification of QTL, genotypic profiling, genomic studies, and marker-assisted selection. SSR (microsatellite) markers are user-friendly and efficient in detecting polymorphism, but they detect few loci. TRAP is a relatively new PCR-based technique that detects a large number of loci from a single reaction without extensive pre-PCR processing of samples. In this work, we used both SSRs and TRAPs to generate over 700 markers for the construction of genetic linkage maps in a hard red spring wheat intervarietal recombinant inbred population. A framework map consisting of 352 markers accounted for 3,045 cM with an average density of one marker per 8.7 cM. On average, SSRs detected 1.9 polymorphic loci per reaction while TRAPs detected 24. Both marker systems were suitable for assigning linkage groups to chromosomes using wheat aneuploid stocks. We demonstrated the utility of the maps by identifying major QTL for days to heading and reduced plant height on chromosomes 5A and 4B, respectively. The work indicates that TRAPs are highly efficient for genetic mapping in wheat. The maps developed will be useful for the identification of quality and disease resistance QTL that segregate in this population.