Submitted to: Journal of Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/1/2003
Publication Date: 1/1/2004
Citation: Bormans, C.A., Marchetti, M.A., Johnson, C.W., McClung, A.M., Park, W.D. 2004. Molecular markers linked to the blast resistance gene pi-z in oryza sativa for use in marker assisted selection. Journal of Theoretical and Applied Genetics. 107:1014-1020. Interpretive Summary: Blast disease caused by Pyricularia grisea causes economic losses in yield and milling quality in many areas of the world where rice is grown. Within the United States, breeders endeavor to develop new rice cultivars that possess broad spectrum resistance to the races of blast that occur within U.S. rice growing regions. This has proven to be an effective way to maintain the economic value of the crop, reduce production costs, and limit the amount of pesticides that are used. Developing molecular markers that are associated with blast resistance genes will make selection of resistant plants more effective and will decrease the development time for new rice cultivars. The results of this research document the development of molecular markers that are associated with the Pi-z blast resistance gene that will be useful in both medium grain and long grain cultivar development programs
Technical Abstract: We have identified DNA markers that cosegregate with the blast resistance gene Pi-z using microsatellite markers found in public databases and degenerate primer pairs based on the P-loop, nucleotide binding site and kinase domain motifs of previously cloned resistance genes. These markers are ploymorphic in a wide range of germplasm, including the narrow crosses characteristic of applied rice breeding programs. They can now be used as an alternative to conventional phenotypic screening for detection of blast resistance genes, allowing rapid introgression of blast resistance into susceptible varieties as well as incorporation of multiple resistance genes into one line for more durable blast resistance.