Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: December 1, 2001
Publication Date: June 1, 2002
Citation: MCCLUNG, A.M., FJELLSTROM, R.G., BERGMAN, C.J., BORMANS, C., PARK, W.D. INTEGRATION OF MOLECULAR MARKERS INTO A CULTIVAR DEVELOPMENT PROGRAM. RICE TECHNICAL WORKING GROUP MEETING PROCEEDINGS. 2002. p. 48.
Much of the recent research using molecular tools for rice germplasm improvement has focused on using germplasm, traits, and production practices that are not relevant to the U.S. The objectives of this research were to develop DNA markers that would be of use to U.S. breeding programs.We have been successful in developing molecular markers for amylose content which largely controls rice cooking and processing quality various resistance genes for rice blast disease, grain aroma, cooked kernel elongation and semidwarf plant height. We have also demonstrated that molecular markers can be very effective tools for quality assurance. We are using markers to verify heterozygosity and parentage of F1's and to eliminate inadvertant selfs. Markers can also be used to expedite recovery of a recurrent parent during backcrossing or eliminate residual genetic variability prior to release of a new cultivar. Most importantly, markers can be used to more accurately select for traits that would be otherwise distorted by the environment or hidden by the presence of other genes. The next steps in our research will include developing DNA markers for milling yield, partial resistance to blast, sheath blight tolerance, alkali spreading value, grain chalkiness, and additional blast resistance genes. These tools will allow breeders to fix key traits early in the selection process so that only the most promising breeding lines are advanced to large scale field tests and less effort will be expended on materials that would ultimately be dropped. This will also allow breeders to expand the number of progeny within the subset having the desirable traits and will increase the opportunity for genetic recombination in quantitatively inherited traits.