Аннотация:The phylogenetic reconstructions of Polygonoideae from nuclear ITS1-2 sequences are compared with morphological data, with special attention to Polygonum and Atraphaxis. In the ML-tree after Eriogonum taken as an outgroup, consecutively branched off the members of Fagopyrum, Persicarieae, Calligonum, Oxygonum, Pteroxygonum, Rumiceae, and Polygoneae. The last includes highly supported clades: 1) Muehlenbeckia, Reynoutria, and Fallopia; 2) Atraphaxis; 3) Duma; 4) Polygonella + Polygonum. In the Atraphaxis clade the members of sections Atraphaxis and Tragopyrum are intermingled not supporting taxonomic division of the genus. The ITS1-2 sequences of majority Atraphaxis species differ by 1-4%, and bootstrap values for most nodes are low. Five Polygonum species are nested in the clade Atraphaxis. Except of perianth structure they share characteristics of growth form, inflorescence and pollen structure with Atraphaxis. Some specimens grouping with various Atraphaxis species might be hybrids. At the base of clade Polygonum the members of Polygonum sect. Duravia group and Polygonella share palynotype Duravia, what let to combine them in Polygonella or in Polygonum. The other Polygonum species are distributed among two clades comprising: 1) the members of sect. Polygonum from temperate zone of North Hemisphere; 2) P. molliiforme Boiss. and P. bornmuelleri Litv. from sect. Pseudomollia with specific palynotype nested among the rest species of Polygonum sect. Polygonum from Middle and Central Asia with palynotype Avicularia. Fine peculiarities of exine surface confirm division of these Polygonum species in two clades. Allopolyploidy was an important way of speciation in Atraphaxis and Polygonum.
The study was supported by the RFBR grant 11-04-01300.