Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 11/1/2002
Publication Date: 8/4/2003
Citation: Johnson, V.A., Gibbons, J.G., Moldenhauer, K.A., Wang, Z., Jia, Y. 2003. Rice variety improvement using marker-assisted selection. In: Norman, R.J., Meullenet, J.-F., editors. B.R. Wells Rice Research Studies 2002. Fayetteville, AR: Arkansas Agricultural Experiment Station. Series 504:66-72. Interpretive Summary: No IS required.
Technical Abstract: Rice breeding traditionally has involved many generations of selection on the basis of phenotypic expression and selfing to develop lines for commercial release. DNA marker-assisted selection accelerates the breeding process by allowing selection for desired traits to take place independent of environmental influence and plant maturity. Developing DNA markers that are closely linked with desired traits allows selection of plants possessing those traits to take place prior to trait expression. PCR-based techniques that are faster and more accurate have been developed for analyzing marker data. Advancements in DNA marker technology and the increasing shift to PCR based analysis techniques have led to the development of co-dominant and dominant markers for use in selection. This provides an opportunity to increase greatly the speed and efficiency of the selection process. The objectives were to accelerate the development of improved cooking quality and blast disease resistance in rice cultivars using two well-characterized molecular markers. A co-dominant rice microsatellite marker. RM 190, is used to predict cooking quality of the milled grain. It is located within the 5' blanking region of the waxy gene which is involved in determining amylose content of the grain, which in turn influences cooking quality. The other marker that has been used is a dominant gene marker that is used to monitor the incorporation of the rice blast resistance gene Pi-ta into improved rice varieties and to verify the results of pathogenicity tests.