An Evaluation of Baum et al.'s Assessment of the Genomic System of Classification in the Triticeae

Abstract

We have critically evaluated Baum, Estes, and Gupta's (1987) assessment of the genomic system of classification in the tribe Triticeae. They have raised some valid concerns about basing a taxonomic classification on genome relationships. However, some of their objections are ill-founded. Baum et al.'s contention that genome analysis can only supplement other criteria in assessing phylogeny is inaccurate. Genome analysis by itself has yielded extremely useful information on phylogenetic relationships in the Triticeae, and their assertion that an individual morphological trait be given the same weight as genomic relatedness is not tenable. Moreover, these authors have adopted cladistic algorithms in the Triticeae, an analysis appropriate only in groups where reticulation has not occurred. Evolution in the Triticeae is highly reticulate, the main sources of reticulation being allopolyploidy and homoploid recombinational speciation.