Inheritance and linkage relationships of morphological and isozyme loci inAs-genome diploid oat (Avena spp.)

Morphological and isozyme markers are useful supplements to molecular marke r maps and can be used in comparative mapping studies. Isozymes, as neutral markers, have been used to study genic and evolutionary relationships amon g related species. In this study, the genetics of six morphological traits and isozyme variants of four enzyme systems were investigated with F-2/F-2: 3 populations derived from three crosses of three As-genome diploid oat (Av ena spp.) accessions. All traits and variants conformed to a model of monog enic inheritance except for lemma color. The four enzyme systems yielded si x putative variant isozyme loci. Phenotypic data of the five monogenically inherited morphological traits and six isozyme loci were subjected to a pai r-wise linkage analysis. Five linked pairs of loci were found. Multipoint l inkage analysis identified a loose linkage group of two morphological and t wo isozyme loci. Included in the linkage group was a locus conferring alkal ine P-galactosidase (Bgl1) and an esterase (Ests) locus, A similar linkage has been observed in hexaploid oat and barley, Additional studies are plann ed to verify and assign the small linkage group and to assign the remaining unlinked markers. This new information will facilitate further mapping com parisons and evolution studies within Avena.