2012 Annual Report 1a.Objectives (from AD-416): Genotyping maize populations segregating for multiple virus resistance. 1b.Approach (from AD-416): Mapping resistance to multiple viruses in maize inbred line Oh1VI is needed. We will send seed of recombinant inbred lines derived from a cross of Oh1VI x Oh28 to the cooperator. The cooperator will genotype the lines using publicly available markers and share the results with us. The genotypic data will be used to map resistance to several unrelated viruses, based on phenotypes determined by USDA. This collaborative project will be carried out as described below and as further described in Attachment 1 to this Agreement ("Project"). 3.Progress Report: The Agricultural Research Service (ARS) Unit supplied Pioneer Hi-Bred with seed for 260 recombinant inbred lines derived from Oh1VI x Oh28, (seed germplasm names) three near isogenic lines carrying the potyvirus resistance genes Wsm1, Wsm2 and Wsm3, and two lines carrying putative mutator insertions into Wsm1 and Wsm2. Pioneer returned results for genotyping with 760 single-nucleotide polymorphism (SNP) markers to ARS. This information was used to build a molecular marker map for the Oh28 x Oh1VI population, and to identify Pa405 sequences inserted into the Wsm1, Wsm2 and Wsm3 near isogenic lines. This project augments research proposed in the parent project under Objective 1: Develop corn and soybean virus disease control strategies; and sub-objective 1.A: Characterize the nature of host resistance.