Polyploidy and new chromosome counts in Anaphalis (Asteraceae: Gnaphalieae) from the Qinghai‐Tibet Plateau of China

Abstract

Anaphalis is one of the largest genera of the Asian Gnaphalieae (Asteraceae) and is most diversified on the Qinghai‐Tibet Plateau. The chromosome numbers and karyomorphology of six species from seven populations were investigated for the first time for this region. Chromosome numbers have been newly documented for four species: Anaphalis deserti (2n = 56 = 24 median [m]+ 24 submedian [sm]+ 8 acrocentric [st]); Anaphalis plicata (2n = 56 = 26m + 30sm); Anaphalis xylorhiza (2n = 28 = 2 median point [M]+ 14m + 12sm); and Anaphalis rhododactyla (2n = 56 = 32m + 24sm). Two further counts are in agreement with the previously reported numbers, that is, Anaphalis royleana (2n = 28 = 4M + 6m + 18sm) and Anaphalis margaritacea (2n = 28 = 12m + 16sm). A new polyploid cytotype (2n = 56 = 26m + 30sm) was found in the Zougong population of A. margaritacea. Polyploidy is for the first time reported for Anaphalis, with four out of seven counts being tetraploid. Our cytological results suggest that polyploids might have played an important role in the evolution of Anaphalis on the Qinghai‐Tibet Plateau.

Phylogenetic relationships in Helichrysum (Compositae: Gnaphalieae) and related genera: Incongruence between nuclear and plastid phylogenies, biogeographic and morphological patterns, and implications for generic delimitation

“…lib.kobe-u.ac.jp/infolib/meta_pub/G0000003asteraceae_e), Nesom (2006a, b), Galbany-Casals & al. (2009b) and Meng & al. (2010), and are compiled in Table S1 (Electr.…”

Evolutionary diversifications of plants on the Qinghai-Tibetan Plateau

“…Peterm. (Yuan and Yang, 2006), Rheum (Liu et al, 2010), and Anaphalis (Meng et al, 2010). Wu et al (2010) suggested that the tetraploid cytotypes of Allium przewalskianum Regel had evolutionary advantages over diploids in colonizing and/or surviving the arid habitats of the QTP.…”

Chromosome numbers, karyotypes, and polyploidy evolution ofAnaphalisspecies (Asteraceae: Gnaphalieae) from the Hengduan Mountains, SW China

“…Combined with published chromosome counts from Meng et al (2010), a total of 39 populations representing 18 taxa in Anaphalis are available from the Qinghai-Tibet Plateau and Hengduan Mountains, in which 23 populations have second polyploidisation (59%), representing 14 species (78%) of the genus (Table 1). Infraspecific polyploidy is also common in Anaphalis.…”

“…Although six species have been reported with cytological data from south-western China recently (Meng et al 2010), there is still a large number of species without chromosome information from this region. In this study, we first accumulated chromosome data on Anaphalis with a broad sampling from the Hengduan Mountains and then evaluated the possible role of polyploidy and karyotypic evolution.…”