Classification of cultivated barley (Hordeum vulgare). 1. Historical aspects, and phenetic character analysis of some characters by information theory and by spatial autocorrelation

Abstract

A brief historical sketch of the classification of barley (Hordeum vulgare L.) cultivars is presented along with reference to key reviews on this subject. Characters, utilized in the comprehensive study on the barley cultivars of North America by Aberg and Wiebe (U.S. Department of Agriculture Technical Bulletin 942), were subjected to a series of phenetic character analyses using an information theory model and a spatial autocorrelation model. The ranking of the 48 characters in order of their importance (for classification and identification purposes) from the character analysis by information theory was compared with the previous rating of characters made by Aberg and Wiebe and was found to differ significantly. Numerous trials of character analysis by spatial autocorrelation using various Minkowski distances, setting various values among three parameters, never yielded results comparable with those obtained by Aberg and Wiebe. Among those trials, a few combinations of values for the three parameters (X, Y, and Z) yielded results comparable with those obtained with character analysis by information theory. Those same combinations of values were found by Estabrook and Gates (Taxon, 33: 13–25) in their study of Banisteriopsis in 1984, where they also developed the method of character analysis by spatial autocorrelation. Kernel weight was found to be the most important character.