Analysis of Wild Evergreen Azalea Populations of the Kirishima Mountains based on Multivariate Analysis of Morphological Characters

Abstract

To classify and estimate the wild evergreen azalea populations in the Kirishima Moutains, principal component analysis and cluster analysis were applied using morphological characteristics and compared with chloroplast DNA polymorphisms.
1. Wild azalea populations were divided into three clusters; Rhododendron kiusianum, R.keampferi and natural hybrids groups by cluster analysis. R.kiusianum and R.keampferi clusters were composed of individuals, which had chloroplast DNA patterns of each species and the natural hybrid cluster consisted of both DNA patterns.
2. On principal component analysis, the first principal component with a high contribution ratio expressed general morphologic characteristics of the wild azalea populations. This first principal component increased continuously from R.kiusianum at high altitude, natural hybrids, and to R.keampferi at the foot of mountain. The distribution of chloroplast DNA polymorphisms of azalea populations indicated correlation with this first principal component.