A multivariate morphometric study and revision of Deutzia, ser. Parvilforae

Abstract

Flower specimens of one hundred and forth eight individuals from China and Korea were sampled to investigate patterns of intraspecific variation and to evaluate recognition of taxa within series Parviflorae (Deutzia parviflora var. parviflora, var. amurensis, var. micrantha, D. glabrata, and D. mollis; sensu Huang) of sect. Mesoduetiza, genus Deutzia using morphometric analysis. Generally the morphological discontinuity among D. parviflora complex except D. glabrata was not evident in the number of rays, the density of hairs (per 3㎟), flower size, leaf length, and leaf width. In the PCA, strong discontinuities exist between D. mollis/D. glabrata and D. parviflora complex in plots of PC 1 vs 2 and 1 vs 3. However, much overlap among D. parviflora complex occurs in the left and central regions of the PCA. The best single qualitative character for separating var. parviflora from var. amurensis, however, is a presence of central ray in leaf. Considering the geographical distribution of var. amurensis and var. parviflora with a presence/absence of central ray, continued recognition at the infraspecific level for these taxa is supported. The current morphological study supports the treatment of sers. Parviflorae and Glabratae within sect. Mesodeutzia as a unified group rather than as two different series (sensu Huang).