Variation Within and Between Some Perennial Urochloa Species

Abstract

To explore the patterns of variation in a collection of perennial Urochloa species two spaced plant experiments were carried out. The first contained 65 of the 83 accessions in the collection. The collection contained five named species. Simple agronomic and morphological data were recorded and various methods of numerical analysis were applied to the results. From the first experiment we find evidence for continuous variation both within and between some of the species. This limits the value of taxonomic classifications and poses problems for communication between interested bodies. Pattern-seeking methods can be used to alleviate such problems by aiding in the delineation and descriptions of taxa. Data from experiments in successive years could not sensibly be combined and the implications of this and other results are discussed in relation to genetic resource programs and taxonomy.