Ecological Anatomy of Plagiorhegma dubia Maxim. (Berberidaceae)
The anatomy of the overground organs of Plagiorhegma dubia Maxim. (Berberidaceae) is discussed. It is an early spring ephemeroid. It is the rare Red Book species and is protected in Khabarovsk krai. It belongs to the third category. Micromorphological signs are revealed as the reflection of ecological preference of species. First, mesophily of this species is reflected in the large thickness of lamina, big mesophyll cells and weak sclerification of the leaf tissue. Mesomorphic features characterize this species as the forest phytocenotype. Second, upper palisade mesophyll, hypostomic epidermis and compact mesophyll show the heliophilous character of this species. Light leaf structure is associated with early spring synusia of this species in mixed coni-ferous-broadleaved forests of East Asia. Third, considerable extent of the epidermis walls, combined epidermis with different-sized stoma, reduction of the vascular cambium in pedicel represent ephemeroid phenorhythm of this species. This species realizes hereditary features as the forest ephemeroid within the northern natural habitat. Rarity of the species, in addition to its old age and location in the border natural habitat is mostly related to anthropogenic transformation of forest formations.