Variation among Australian accessions of Vigna vexillata for traits of agronomic, adaptive, or taxonomic interest

Abstract

Variation among 79 accessions of Vigna vexillata was evaluated for a range of traits of potential agronomic, taxonomic, or adaptive significance, using potted plants grown in the glasshouse over summer. There was significant variation among accessions for all of the traits evaluated except for tuber morphology. The nature and extent of variation are likely to be of agronomic interest in a plant improvement context. Variation among accessions for quantitatively inherited traits relating to phenology, biomass accumulation (vegetative growth, seeds, and tubers), and pod and seed traits was, in most instances, normally distributed, with no evidence of large discontinuities in response. There was evidence of photoperiodic adaptation among accessions from different latitudes and some interrelations between quantitative traits, for which there were usually plausible physiological explanations. Among the several qualitative traits evaluated, there was evidence of minor linkages between some alleles. There was no evidence of major discontinuities in the observed variation, and no evidence of aggregations of traits into distinctive or geographically discrete morphotypes. It is concluded that V. vexillata is relatively homogeneous across the wide geographical range over which it occurs within Australia.