Morphological diversity in tetraploid wheat landrace populations from the central highlands of Ethiopia

Seven tetraploid wheat populations consisting of 122. entries collected from Shoa and Gojem Administrative Regions of Ethiopia. were studied for variation of eight morphological characters that have two or more phenotypic classes. Monomorphism was common in many of the populations for awn length and glume pubescence, whereas the rest of the Characters exhibited polymorphism in varying degrees. Awn condition was found to be a fixed character in the entire collection. The lowest level of diversity was observed for glume pubescence (excluding awn condition) and an intermediate to a high level of diversity for all the other characters There was no significant difference among all the estimates of mean diversity for the populations and districts. Although only glume pubescence showed significant differences, the analysis of variance of diversity for individual characters indicated most of the variation to be due to differences among districts rather than among populations within districts. This was also confirmed by a hierarchical analysis of variance of diversity, which detected significant difference only among districts. It is suggested that future collections should covet more different areas rather than having more samples from similar areas. The species composition of the collections is described. Possible adaptive mechanisms of some of the characters arc also discussed. Copyright © 1991, Wiley Blackwell. All rights reserved