The comparative morphology and anatomy of leaves in the serpentine endemic Aster hispidus Thunb. var. leptocladus (Makino) Okuyama and its close relative A. hispidus var. hispidus were examined. Our morphological anal...The comparative morphology and anatomy of leaves in the serpentine endemic Aster hispidus Thunb. var. leptocladus (Makino) Okuyama and its close relative A. hispidus var. hispidus were examined. Our morphological analysis revealed that the leaves of A. hispidus var. leptocladus were significantly smaller and narrower than those of A. hispidus var. hispidus. In particular, our anatomical analysis indicated that a decreased cell number of the horizontal axis of a leaf was involved in A. hispidus var. leptocladus. This was the same process as the changing pattern of the leaves of rheophytic species, and so, similar morphological leaf modifications occurred under different selection pressures of the serpentine soil and flooding frequency of river-stream.展开更多
文摘The comparative morphology and anatomy of leaves in the serpentine endemic Aster hispidus Thunb. var. leptocladus (Makino) Okuyama and its close relative A. hispidus var. hispidus were examined. Our morphological analysis revealed that the leaves of A. hispidus var. leptocladus were significantly smaller and narrower than those of A. hispidus var. hispidus. In particular, our anatomical analysis indicated that a decreased cell number of the horizontal axis of a leaf was involved in A. hispidus var. leptocladus. This was the same process as the changing pattern of the leaves of rheophytic species, and so, similar morphological leaf modifications occurred under different selection pressures of the serpentine soil and flooding frequency of river-stream.