|Moldenhauer, K A|
Submitted to: Arkansas Agricultural Experiment Station Research Series
Publication Type: Experiment Station
Publication Acceptance Date: 7/6/2007
Publication Date: 8/8/2007
Citation: Boyett, V.A., Gibbons, J.W., Bryant, R.J., Eizenga, G.C., Moldenhauer, K.K. 2007. Utilization of trait-linked DNA markers in rice breeding. In: R.J. Norman, J.-F. Meullenet and K.A.K. Moldenhauer (eds) B.R. Wells Rice Research Series 2006. Arkansas Agricultural Experiment Station Research Series 550: 43-50. Available at http://arkansasagnews.uark.edu/408.htm
Technical Abstract: DNA marker technology is being used in U.S. rice breeding programs to enhance development of rice cultivars with improved cooking quality and genetic resistance to rice blast disease. Because there is a continuous threat of race shifts within the Magnaporthe grisea populations found in rice fields that can lead to a breakdown in host-plant resistance, it is important to identify and pyramid additional sources of resistance into new cultivars. Frequently, though, highly disease-resistant cultivars possess other agronomic traits that are undesirable, including cooking qualities that are unacceptable for U.S. market classes. Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers linked to these specific traits are used to predict cooking quality of the milled grain and screen for blast-resistance genes. A major focus of using DNA markers in the breeding process is to be able to efficiently select progeny of segregating populations with both improved blast-disease resistance and good cooking quality with marker-assisted selection (MAS). The markers can also be used to resolve issues of seed purity, cultivar identification, and correlation between genotype and phenotype. Recently the emphasis has been on using markers to genotype a colleciton of elite breeding lines. Genotyping this working germplasm collection gives the breeders additional information regarding the genetic background, diversity, and potential of the parental material. Over 15,000 individual genomic DNA smaples were processed for MAS in 2006, and up to 27 trait-linked markers were used in their analysis.