Cereal Chem 62:377-392   |  VIEW ARTICLE
Computer-Aided Analysis of Gliadin Electrophoregrams. II. Wheat Cultivar Identification and Class Comparisons.

H. D. Sapirstein and W. Bushuk. Copyright 1985 by the American Association of Cereal Chemists, Inc. 

A computer-based methodology is described that facilitates identification and comparison of wheat cultivars based on gliadin electrophoregram relative mobility and band density data. The basic programmed task compares a numerically encoded unknown or test polyacrylamide gel electrophoretic (PAGE) pattern with all reference PAGE patterns in the data base. For each comparison, four classes of events are scored: matching bands, nonmatching bands in the unknown and reference electrophoregrams, and bands that differ significantly only in staining intensity. These parameters are used in an equation to quantify electrophoretic pattern homology that determines the order of cultivar ranking. A separate computer program evaluates the uniqueness of the unknown electrophoregram and identifies diverse genotypes. Plotting software that provides a graphic analysis of electrophoretic pattern composition was developed to identify and differentiate matching and nonmatching bands in compared electrophoregrams. User-established parameters include least significant difference thresholds for comparing relative mobility and band density. The user may supply pedigree information and coded wheat class, quality, or region attributes for each reference electrophoregram. These data assist in the interpretation of program output and provide a basis for differentiation of cultivars according to functional type by gliadin composition. Two versions of the cultivar-ranking formula are described, and the performance of the computerized system is illustrated for several test input electrophoregrams against a PAGE pattern data base of 122 common spring, winter, and durum wheat cultivars.