Submitted to: Journal of Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/28/1996
Publication Date: N/A
Citation: Interpretive Summary: Maize mosaic virus (MMV) causes a serious disease of corn with a widespread distribution through tropical and subtropical regions of the world. An understanding of the genetic basis of resistance to this virus in corn would aid plant breeders in developing new virus resistant varieties. We demonstrated that resistance to MMV in the MMV-resistant inbred Hi31 is primarily due to a single gene located on chromosome 3. This resistance gene, Mv1, was placed on the maize genetic map of chromosome 3 relative to molecular markers. This information is being used to select for new resistant lines of corn by selection for the associated molecular marker, a procedure that is cheaper, easier and more reliable than screening for virus resistance under field conditions.
Technical Abstract: Maize mosaic virus (MMV) causes a serious disease of corn with a widespread distribution through tropical and subtropical regions of the world. An understanding of the genetic basis of resistance to this virus in corn would aid plant breeders in developing new virus resistant varieties. The objective of this study was to determine the genetic basis of resistance to maize mosaic virus (MMV). Molecular markers were used to map resistance loci to MMV in a set of 91 maize (Zea mays L.) Recombinant inbred lines (RILs) derived from the cross between Hi31 (a B68 conversion resistant to MMV) and Ki14 (a Thai inbred susceptible to MMV). The RILs were evaluated for MMV resistance in disease nurseries in Hawaii in the winter of 1993 and the summer of 1994. Twenty-eight highly susceptible RILs were chosen for gene mapping using the pooled-sampling approach. Initial evidence from the pooled DNA indicated that restriction fragment length polymorphism (RFLP) probes on chromosome 3 near the centromere were biased to the susceptible parent allele. Analysis of 91 RILs at 103 RFLP loci confirmed the presence of a major MMV resistance gene on chromosome 3. The resistant allele at this locus, previously named mv1, is present in the resistant parent Hi31 and traces back to the Argentine parent used in conferring common rust resistance to B68. We conclude that resistance to MMV in B68 and Caribbean flints involves a major gene mv1 on chromosome 3, located between RFLP markers umc102 and php20508.