Fine Mapping Of The Resistance Gene Rscmv2 To Sugar-cane Virus In Maize

Maize (Zea mays L.) dwarf mosaic (MDM) is one of widespread viral diseases in the world, it is useful for the resistant breeding to have the resistance genes identified. The two resistance genes Rscmv1 and Rscmv2, located on chr.6 and chr.3, were identified from the inbred line Siyi with an elite agronomic traits. The resistance of BC4F6, BC4F7, BC4F8 populations were identified in 2 locations with 3 years to fine mapping the gene Rscmv2 which showed the specific resistance at adult stage with the molecular markers developed. The results were as follows.1. 12 recombinant plants of BC4F6 populations to MDM were screened out with the analysis of the markers in Hainan, and then the resistance gene Rscmv2 was mapped between the markers 3-ac36-9 and 3-AC16-20, the physical distance between the two markers is 5.54 Mb.In 2009, 170 recombinant plants of BC4F7 populations were screened out in 4 seedtimes, and then the resistance gene Rscmv2 was mapped between the markers 3-ac50-8 and B1601, the physical distance between the two markers is 612.50 Kb. In 2010, 7 recombinant plants of BC4F7 populations were were screened out, and then the resistance gene Rscmv2 was mapped between z52-4 and z55-4, the physical distance between the two markers is 382.20 Kb.2. 4 pairs of markers , z50.5-3, z52-4, z55-4, z56-8, were developed with the polymorphisms between the parents to fine mapping the gene. 5 BAC covered 814.588 Kb with 39 small DNA segments were resequenced by the contigs of the inbred line B73, and the location of the markers developed were sequenced to fine mapping.