The organisms constantly face to variable environmental conditions. Phenotypic plasticity found of individual might be an important role for survival to compensate its homeostasis against environmental variation. In the plant, leaf morphological variations are well known even within a plant. Especially, the compound leaves exhibit large variation in the form, however, most of morphometric studies have been accumulated on simple leaves.

Here, we reveal morphological dynamics of rosette leaves in Geum japonicum (Rosaceae) with compound radical leaves, to recognize leaf morphology in detail, suggesting seasonal phenotypic plasticity (Sato, 1988) by size – shape mesurements.

We collected 6 individuals per month on 5 field sites for analysis of leaf variation within a population. 12 individuals in a green house were used for leaf variation analysis after sequential collection of leaves within a plant. Sampled radical leaves were measured on each plant. All sample sets were used for PCA to overview the leaf variation during seasonal plant development.

Consequently, there are at least 3 types of leaf morphology associated with season in Geum japonicum . Results showed dissection decrease from spring to winter, and size extend in summer. From these, this study consider suitability for season in Geum japonicum .