Plant, Animal & Microbe Genomes X Conference

January 12-16, 2002
Town & Country Convention Center
San Diego, CA

Workshop: Compositae
            

CANDIDATE GENE APPROACHES TO AGRICULTURALLY IMPORTANT TRAITS IN LETTUCE

¹ Department of Vegetable Crops, University of California Davis, One Shields Ave., Davis, CA 95616

² KEYGENE N.V. - Molecular Marker Services, P.O. Box 216, 6700 AE Wageningen, The Netherlands

³ Biology Department, University of Massachusetts, 100 Morrissey Blvd., Boston, MA 02125

One of the primary goals of the Compositae Genomics Project (CGP) is to utilize information being generated in model species such as Arabidopsis for the improvement of crops species such as lettuce and sunflower. An extensive EST collection has been generated from two genotypes of lettuce. These genotypes were the parents of our core mapping population from which we have developed F_2:3 families and more recently a set of recombinant inbred lines. A variety of qualitative and quantitative traits have been analyzed genetically in this population, including bolting, root architecture, and leaf morphology. Loci determining many of these traits have been identified. Homologs of candidate genes of known function from studies in Arabidopsis and other species are being identified in the EST collection and will be mapped relative to the phenotypic traits. Sequence polymorphisms will be identified by comparisons between homologs from the two parents. Several approaches have been utilized to identify resistance gene candidates (RGCs) including PCR degenerate oligonucleotides and a large cDNA strategy in addition to identification of homologs in the EST collection. We have so far identified at least 10 families of RGCs. These are being mapped relative to phenotypic resistances using multiple populations. These data are being integrated with the consensus map using common anchor markers.