Associations among inbred lines of maize using electrophoretic, chromatographic, and pedigree data : 2. Multivariate and cluster analysis of data from Iowa stiff stalk synthetic derived lines.

Associations among 17 "Iowa Stiff Stalk Synthetic" derived inbred lines of maize (Zea mays L.) were determined using multivariate and cluster analysis. Objectives were to assess the level of unique characterization among lines afforded by reversed-phase high-performance liquid chromatography (RP-HPLC) of zeins and starch gel electrophoresis of isozymes and to compare associations among lines revealed by biochemical and pedigree data. Isozymic data for 33 loci provided unique discrimination among 88% of the lines; 2 closely related lines were indistinguishable. Seventy-one percent of the lines could be uniquely and unambiguously identified by RP-HPLC. Biochemical data showed associations between lines that would be expected on the basis of pedigree. Nevertheless, different associations were revealed by allozymic and chromatographic data. Although these data permitted a high degree of unique identification, additional markers, covering a larger proportion of the genome, are needed to more adequately monitor similarities among genes that respond to selection during plant breeding.