Abstract
The tissue and developmental specificity of acid phosphatase (ACPH) isozymes of Triticum aestivum (2n=42, genomes AABBDD) and its progenitor species T. turgidum (2n=28, AABB) and T. tauschii (2n=14, DD) have been determined and compared using the zymogram technique. Ten isozymes have been detected in the tissues of T. aestivum. Three of these display minor activity and can be resolved on a zymogram only when one or more major forms of similar electrophoretic mobility are absent (achieved by use of aneuploid derivatives of the cultivar Chinese Spring). Tissue and/or developmental variation in relative staining intensity, suggestive of variation in the quantity of active enzyme present, was observed for each of the seven major isozymes. Four of these were present in all tissues at all developmental stages examined while three were not detected at certain developmental stages and/or in certain tissues. Isozymes homologous to the seven major forms of the hexaploid were detected in one or the other of the progenitor species. No differences in the pattern of developmental and tissue specificity for acid phosphatase isozymes were observed between the hexaploid and its progenitor species. However, ACPH-4, coded by a structural gene linked to chromosome 4A, differs in electrophoretic mobility between T. aestivum and T. turgidum, indicating that divergence has occurred between these species at the Acph4 locus since the origin of the hexaploid. No differences were observed in the molecular weight of five of the major ACPH isozymes. This finding, plus the results of the developmental study and the earlier demonstration that the structural genes for six isozymes (including four of those whose molecular weight was determined) are linked to homoelogous chromosomes, provides powerful evidence in support of the suggestion that the structural genes for the acid phosphatases of hexaploid wheat are homoeologously related.
Torres, Michael Angel (1975). Developmental specificity and evolution of acid phosphatase isozymes of Triticum aestivum and its progenitor species. Doctoral dissertation, Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -181936.