Allozymic Variability among Maize Inbred Lines and Hybrids: Applications for Cultivar Identification1

Abstract

The potential use of electrophoretically detected allozymic variability for maize (Zea mays L.)cultivar identification was assessed by surveying the variability of 12 enzyme systems, involving 22 loci, among 110 public inbred lines and 153 commercial hybrids used in Canada. Summed over loci, 55 and 56 alleles were detected among the inbred lines and hybrids, respectively. All but a few alleles were common to both groups. For most loci, several alleles were observed at low frequencies among the inbred lines and the hybrids. These rare alleles, as well as unique combinations of alleles within (hybrids only) and among loci, identified 88 inbred lines (80%) and 146 hybrids (94%) with unique fingerprints. Four additional fingerprints were observed among the remaining nine hybrids. Unexpected allozymic variability was observed within 59% of the hybrids. Comparisons of the apparent hybrid type (single, threeway, double, etc.) as determined electrophoretically with the hybrid type indicated by the company showed discrepancies for 32% of the hybrids. Our results suggest that sufficient allozymic variability exists among maize cultivars to be useful for cultivar identification.