Marker information in the new oilseed crop, meadowfoam, is limited. Molecular markers to facilitate meadowfoam breeding and cultivar improvement are not available. The knowledge of genetic relationships among recent germplasm is not known. The objectives of this study were (i) to gain an understanding of genetic diversity and relationship patterns among germplasm. (ii) to construct a genetic linkage map, and (iii) to map genes and QTLs (Quantitative Trait Loci) underlying erucic and dienoic acid concentrations in seed oils. We fingerprinted meadowfoam 41 accessions of section inflexae of family Limnanthaceae using 176 AFLP markers. Polymorphic information content (PIC) scores were high in 42.6% of the markers and ranged from 0.45 to 0.5. Genetic distance estimates ranged from 0.14 to 0.55 with an average of 0.44. The clustering phenogram showed concordance with taxonomic classification. The first three principal component analyses accounted for 37% of the total variation of genetic distance estimated. We concluded that the genetic diversity of elite and exotic germplasm in section Inflexae was high. The AFLP genetic linkage map for meadowfoam was built using inter-subspecific backcross progeny between OMF40-11 (Limnanthes. alba spp. alba) and 0MF64 (L. alba spp. versicolor). The map was comprised of 104 loci in five linkage groups, with 14 to 28 loci per linkage group. The map covered 698.3 cM with a mean density of 6.7 cM. The lengths of the linkage groups varied from 110.3 to 168.0 cM. AFLP loci were randomly distributed throughout the genome with no centromeric clustering. Genetic maps of meadowfoam can be rapidly Constructed using a small number of AFLP primer combinations. We utilized the AFLP genetic linkage map to map genes and QTLs underlying erucic and dienoic acid concentrations in seed oils. The QTL analyses were performed using interval mapping. QTL affecting erucic and dienoic acids was mapped to linkage group four at the E locus, which controlled seed oil phenotypic differences between the two subspecies, alba and versicolor. The effect of E locus was pleiotropic. QTLs with significant effects on content of erucic and dienoic acid other than the effects of E locus were not found in this backcross population. / Graduation date: 2000