Probatova. Chromosome studies on the flora of the Russian Far East

Chromosome studies on the flora of the Russian Far East

Nina S. PROBATOVA
Institute of Biology and Soil Science, Vladivostok, Russia

Chromosome studies on the vascular flora in the Russian Far East (RFE) were initiated in the late 1950s. Now the RFE is the most studied region of Russia in this aspect. New evidence was obtained that sea coasts are a zone of speciation. In the RFE we observe isolation of coastal ecotypes of the widely distributed continental taxa. Since 2007, when the book on karyology of the flora of Sakhalin and the Kurils was issued, we have in total 374 species with chromosome numbers (CN) from Sakhalin and 294 species from the Kurils. The Index of CN for the Primorskii Krai is under preparation and summarizes the CN studies in this territory since 1962 (1247 species, from 593 genera). Recently in Moehringia lateriflora the diploid cytotype (2n=24) was found in the RFE, though 2n=48 is more common for this species, which is widely distributed - from E Europe to N America and ecologically variable; its 24-chromosome race probably is connected with sea coasts. Draba cinerea in Sakhalin (Schmidt Peninsula) and in the continental part of the RFE (the Nylan River basin, Khabarovskii Krai) showed 2n=2x=16: this is southern limit of the species range. Most probably, D. cinerea originated in this part of its present range and migrated to the north, by forming polyploid races (2n=48, 56, 64, 80). Coastal species Scrophularia grayana has 2n=20 in Iturup and Moneron Islands, but 2n=40 - in the continental RFE (South Primorye): these data indicate that the insular part of S. grayana's range could be more ancient than the continental one. Intraspecific karyological polymorphism (in CN and ploidy levels) was also revealed in Acorus calamus, Agrostis trinii, Allium senescens, Bidens parviflora, Calamagrostis brachytricha, Clinopodium chinense, Lysimachia davurica, Oenanthe javanica, Phyllanthus ussuriensis, Poa skvortsovii, P. sichotensis, Potentilla discolor, Scrophularia maximowiczii, Scutellaria strigillosa, Vicia unijuga, Waldsteinia maximowicziana. The study was funded by Russian Fund for Basic Research (RFBR), projects 04-04-49750, 07-04-00610, 11-04-00240.