Aconitase and glucose phosphate isomerase variation in hexaploid wheat

Abstract

The purpose of this study was to determine if isozyme variation could be found in wheat (Triticum aestivum L. em. Thell) for the isozymes aconitase, alcohol dehydrogenase and glucose phosphate isomerase; these isozymes are encoded by genes on wheat chromosomes with loci conferring pest resistance. Two hundred and fifty wheat accessions were examined for variation in the isozymes aconitase and alcohol dehydrogenase using starch gel electrophoresis. Accessions were chosen at random from a collection of hexaploid wheat lines from all over the world. In addition, twenty-one accessions which exhibited unusual variation for either endopeptidase or aconitase were examined for glucose phosphate isomerase variation using isoelectric focusing. While no isozyme variation was seen for alcohol dehydrogenase, variation was detected for aconitase and glucose phosphate isomerase. In addition, the glucose phosphate isomerase phenotypes of wheat lines with the 1B-1Rs and 1A-1Rs wheat-rye translocations were distinguished. Therefore, evaluation of glucose phosphate phenotypes could potentially be used in wheat improvement programs to identify plants which are homozygous for wheat-rye translocations involving chromosome 1. Key words: Triticum aestivum, isozyme variation, wheat improvement