Phylogenetic relationships and evolution of Crassulaceae inferred from matK sequence data

Abstract

Chloroplast gene matK sequence data were used to estimate the phylogeny of 112 species of Crassulaceae sampled from 33 genera and all six recognized subfamilies. Our analyses suggest that five of six subfamilies recognized in the most recent comprehensive classification of the family are not monophyletic. Instead, we recovered a basal split in Crassulaceae between the southern African CRASSULA: clade (Crassuloideae) and the rest of the family (Sedoideae). These results are compatible with recent studies of cpDNA restriction site analyses. Within Sedoideae, four subclades were also recovered: KALANCHOE:, Leucosedum, Acre, and AEONIUM:; evidence also exists for a TELEPHIUM: clade and SEMPERVIVUM: clade. The genus SEDUM: is highly polyphyletic with representatives spread throughout the large Sedoideae clade. Sympetaly and polymerous flowers have arisen multiple times in Crassulaceae and thus are not appropriate characters upon which to base subfamilial limits, as has been done in the past. One floral character, haplostemy, appears to be confined to the well-supported CRASSULA: clade. Our analyses suggest a southern African origin of the family, with subsequent dispersal northward into the Mediterranean region. From there, the family spread to Asia/eastern Europe and northern Europe; two separate lineages of European Crassulaceae subsequently dispersed to North America and underwent substantial diversification. Our analyses also suggest that the original base chromosome number in Crassulaceae is x = 8 and that polyploidy has played an important role in seven clades. Three of these clades are exclusively polyploid (SEMPERVIVUM: clade and two subclades within the KALANCHOE: and AEONIUM: clades), whereas four (Crassula, Telephium, Leucosedum, and ACRE: clades) comprise both diploid and polyploid taxa. Polyploidy is particularly rampant and cytological evolution especially complex in the ACRE: clade.

Estimation of Phylogeny of Nineteen Sedoideae Species Cultivated in Korea Inferred from Chloroplast DNA Analysis

“…This pattern has been found in many previous studies of Sedum phylogeny conducted using RAPD analysis (Kwon and Jeong, 1999), matK sequence data (Mort et al, 2001), and chloroplast data (Van Ham and 'T Hart, 1998). In the matK sequence analysis by Mort et al (2001), the phylogeny revealed the polyphylic nature of Sedum species, with S. sexangulare, S. oryzifolium, and S. sarmentosum classified into the Acre clade in the Sedoideae subfamily, while S. rupestre was included in the Sempervivum clade in the Sedoideae subfamily. The polyphyletic position of S. rupestre, as observed in this study, may be explained as follows-in morphological, phenological, and biogeographical contexts, S. rupestre was distinguished with other Sedum species classified in the Acre clade.…”

“…The RAPD-based grouping of 31 S. sarmentosum ecotypes distributed in Korea was strongly related to morphological characteristics (Kim et al, 2008). This pattern has been found in many previous studies of Sedum phylogeny conducted using RAPD analysis (Kwon and Jeong, 1999), matK sequence data (Mort et al, 2001), and chloroplast data (Van Ham and 'T Hart, 1998). In the matK sequence analysis by Mort et al (2001), the phylogeny revealed the polyphylic nature of Sedum species, with S. sexangulare, S. oryzifolium, and S. sarmentosum classified into the Acre clade in the Sedoideae subfamily, while S. rupestre was included in the Sempervivum clade in the Sedoideae subfamily.…”

“…Sedum, the largest genus of Crassulaceae, is a polyphyletic genus that encompasses much of the morphological diversity present in the family. The Sedum genus is, however, still poorly characterized and requires further investigation (Mort et al, 2001). Plants of the genus Sedum occur across the Northern Hemisphere, including in the Mediterranean there is still confusion in the common or public naming system in Korea.…”

Neotypification of Sedum ochroleucum Chaix (Crassulaceae)

“…The series Rupestria was raised to the genus level (Petrosedum Grulich) in the 1984 and recent molecular studies (Mort et al, 2001) confirm the soundness of splitting the polyphyletic genus Sedum into many small new genera, series Rupestria included. However, this split is not yet recognised formally (cf.…”

Phytochemical profile of the stems of Aeonium lindleyi

“…Members of this family are leaf-succulent, usually herbaceous, and often have fi veparted, radially symmetrical fl owers with two whorls of fi ve stamens each. Reported secondary metabolites from Crassulaceae species are fl avonoids, steroids, alkaloids and triterpenoids (Mort et al, 2001).…”