Project Number: 3655-21000-037-01
Project Type: Reimbursable

Start Date: Aug 01, 2003
End Date: Jul 30, 2006

Objective:
Potyviruses routinely cause yield and quality losses in the cucurbits (cucumber, melon, watermelon, and squash) and breeding for resistances is time consuming and labor intensive. We cloned a genomic region from cucumber that cosegregates with the recessive locus (zym) conditioning resistance to Zucchini Yellow Mosaic Virus (ZYMV). The goals of this research are to fine map the sym locus of cucumber, develop a dual-primer PCR marker for selection of potyvirus resistance in cucumber, and complete comparative mapping of potyvirus-resistance loci in cucumber and melon.

Approach:
Mass pollinations will be completed among plants from a cucumber recombinant inbred line heterozygous across the genomic region carrying resistances to PRSV-W and ZYMV. We will use a codominant PCR marker for fine mapping of potyvirus resistances. S1 families will be generated from plants homozygous for the marker and inoculated with ZYMV. Recombination between zym and Prsv-2 will be detected by independent inoculations of the S1 families with PRSV-W and ZYMV. Cucumber BAC clones carrying the PCR marker will be identified. BAC DNA will be digested and FPC used to build a BAC contig. Specific fragments of relative low-copy number regions will be used to reveal PCR-based polymorphisms unique to TMG1, the main source of potyvirus resistance in cucumber. Collaborative research with researchers in Israel and France will allow us to complete comparative mapping of potyvirus resistance loci in cucumber and melon.

Project Team

Havey, Michael

Related National Programs

Plant, Microbial & Insect Genetic Res., Genomics, & Genetic Improv. I (301)