Delimitation of the genus Avena (Gramineae)

Abstract

An historical sketch of the different opinions concerning the generic limits of Avena and its relationships among other closely related genera of the tribe Aveneae is given. Advancement indexes of Avena and its closest allies were calculated. It is found that Avena possesses many primitive characters and in this respect is most closely allied to Arrhenatherum and Helictotrichon. The genera Amphibromus, Deschampsia, Trisetum, and Ventenata possess a greater number of more advanced characters and are considered to be more distantly allied with Avena. Diagnostic characters for Avena have been assessed. Avena macrostachya, a perennial species, has been included together with the annual oats within the generic limits of Avena. A full description of the genus is given.