A numbrical analysis of variation patterns in Australian introductions of Glycine wightii (G. javanica)

Abstract

Numerical methods of classification were used to separate varietal types among 51 introductions of the polymorphic species G. wightii from Africa, India, and South America. Thirty-one morphological and agronomic attributes were used in the classification by the programme MULTBET on the Control Data 3600 computer at Canberra. Preliminary assessment gave four homogeneous groups and two 'nonconformist groups'. The 11 introductions in the latter groups were individually assessed and in some cases reallocated. Finally, six varietal groups were obtained and their interrelationships examined. The morphological and agronomic characteristics of each group are described and related to Bogdan's varietal types. Chromosome counts on 48 of the introductions classified confirmed, with few exceptions, the homogeneity of the diploid (2n = 22) and tetraploid (2n = 44) varietal groups and these bore some relationship to country of origin. A total of 124 introductions were counted of which 54 were diploid, 62 tetraploid, and 8 mixed. The highest proportion of diploids was in Tanzania, Kenya, and Rhodesia. Tetraploids were more common in countries at greater altitudes such as Malawi and Uganda, or in higher latitudes such as South Africa. Numerical methods of varietal classification appear to be a valuable technique for integrating morphological and agronomic data from a number of experiments to evaluate large numbers of introductions of polymorphic pasture species. This aids in the understanding of the relative agronomic performance of introductions and their taxonomic affinities and should lead to more effective collection, introduction, and evaluation of further introductions of the species.