Submitted to: Plant Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/25/2005
Publication Date: 3/1/2006
Citation: Friesen, T.L., Weiland, J.J., Aasheim, M., Hunger, S., Borchardt, D.C., Lewellen, R.T. 2006. Identification of a SCAR marker associated with Bm, the beet mosaic virus resistance gene, on chromosome 1 of sugar beet. Plant Breeding. 125:167-172. Interpretive Summary: Beet mosaic virus (BtMV) is a prevalent disease of sugar beet causing significant yield loss worldwide. In this work we have identified the chromosome locations and identified molecular markers closely linked to a resistance gene highly effective in reducing BtMV. This gene identified as Bm was located to beet chromosome 1 based on molecular markers and the male sterility phenotypic marker. Markers identified should be useful for introgression of this gene into commercial germplasm.
Technical Abstract: Beet mosaic virus (BtMV) is an aphid transmitted, viral disease of beet found worldwide. The Bm gene, a resistance gene effective against BtMV, was identified in the sugar beet line 8500 and backcrossed into a C37 background to produce line C719. Three populations were developed from the cross of line C719 with the susceptible line C37 with the intent of developing markers for use in marker assisted selection. The F2 progeny of three crosses were scored for resistance. Two of the three populations conformed to a 3:1 ratio indicating a single gene trait. Sequence characterized amplified region (SCAR) markers were developed by using bulked segregant analysis (BSA) combined with random amplified polymorphic DNA (RAPD) type markers. The markers showed close association to the Bm resistance gene and were effective in all three populations. This marker will be useful for the introgression of the Bm gene into germplasm. The A1 allele for genetic male sterility, assigned to chromosome 1, was found to be associated with Bm and the SCAR marker sequence used in this population was also used to develop a SNP marker in a second population to validate linkage to chromosome 1.