PAG-I Plant Genome I Conference

Town & Country Conference Center, San Diego, CA, November, 1992.


PG-I: RFLP ANALYSIS OF A SOYBEAN BREEDING POPULATION: GENETIC STRUCTURE AND TRAIT VARIATION

RFLP ANALYSIS OF A SOYBEAN BREEDING POPULATION: GENETIC STRUCTURE AND TRAIT VARIATION.

P. Keim, W. Beavis, J. Schupp, R. Freestone, M. Vahedian, D.M. Webb and T. Gocken. Northern Arizona Univ., Flagstaff AZ 86011-5640 and Pioneer Hi-Bred Int., Johnston IA 50131


Molecular marker analysis has been difficult to use in adapted soybean germplasm because of relatively low levels of diversity. We have exhaustively surveyed 16 cultivars to identify ca. 700 informative RFLP markers. Two of these cultivars had been used to construct a segregating population consisting of 261 F5-derived lines. One-hundred-fifty-five RFLP markers were scored in this population and used for estimating genetic distances (GDR) among the segregating lines. While the genetic composition of individual lines met theoretical expectations, the frequency distribution of GDR estimates was significantly skewed towards zero. This is consistent with repetitive sampling of individual genotypes during inbreeding. Redundant genotypes could then be eliminated from subsequent genetic analyses. Genetic linkage groups among marker loci was determined using MAPMAKER. Trait variation in this population was quantified by replicated field trial at four locations in two years. Marker loci were used to identify regions of the genome that contain QTLs affecting agronomic traits.


Return to Previous Page or Intl-PAG Homepage