A revision of the higher syntaxa of meadows of the Russian Far East has been made on the basis of results of ecological, phytocoenotic and chorological analyses of associations and higher units published by M. Achtyamov (1985, 1987а, б, 1995, 2000) and G. Dymina (1980, 1985). Conceptual basis for existing syntaxonomic system of the meadows and leading diagnostic features of syntaxa have been reviewed. Authors propose to include all diverse Daurian-Manchurian meadows into two different classes. Hygro-mesic meadow communities of bogged flood-plane habitats with excessive moisture supported by subterranean waters have been included in the class Calamagrostietea langsdorffii Mirkin in Achtyamov et al. 1985. Diagnostic species are Anemonidium dichotomum, Calamagrostis langsdorffii, Caltha membran acea, Carex appendiculata, C. schmidtii, Filipendula palmata, Fimbripetalum radians, Galium davuricum, Iris laevigata. Lathyrus pilosus, Lysimachia davurica, Sanguisorba parviflora, Saussurea amurensis, Spiraea salicifolia, Stachys aspera, Nomenclature type of the class is the order Calamagrostietalia langsdorffii Achtyamov et al. 1985. Drought-tolerant xero-mesic meadows of zonal sites with fluctuating moisture regime supported by monsoon climate have been included in the class Arundinello anomalae—Agrostietea trinii cl. nova hoc loco. Nomenclature type of the class is the order Artemisietalia mandshuricae Achtyamov et al. 1985. Diagnostic species are: Aconogonon divaricatum, Adenophora pereskiifolia, A. verticillata, Agrostis trinii, Artemisia desertorum, A. integrifolia, A. stenophylla, Arundinella anomala, Aster tataricus, Campanula cephalotes, Carex diplasiocarpa, Dianthus chinensis, Eupatorium lindleyanum, Galium verum, Gentiana scabra, Geranium vlassowianum, Hemerocallis minor, Iris ensata, Lathyrus quinquenervius, Lupinaster pentaphyllus, Patrinia scabiosifolia, Potentilla fragarioides, Ptarmica acuminata, Ranunculus japonicus, Sedum aizoon, Serratula manshurica, Thalictrum amurense, Trommsdorfia ciliata, Vicia amoena, V. pseudorobus. The ranges of both classes are concentrated in the Manchurian floristic province of Northern Asia, in regions with obvious Pacific and Sub-Pacific climatic regimes. Their western geographical limits run near the Yablonovy mountain ridge in the Eastern part of Baikal region. Westward, the Arundinello anomalae—Agrostietea trinii and Calamagrostietea langsdorffii are replaced by European-Siberian meadows of the Molinio—Arrhenatheretea.
Enhanced Drought Stress Tolerance by the Arbuscular Mycorrhizal Symbiosis in a Drought-Sensitive Maize Cultivar Is Related to a Broader and Differential Regulation of Host Plant Aquaporins than in a Drought-Tolerant Cultivar
