김승철 교수

Woody Sonchus and five related genera (Babcockia, Taeckholmia, Sventenia, Lactucosonchus, and Prenanthes) of the Macaronesian islands have been regarded as an outstanding example of adaptive radiation in angiosperms. Internal transcribed spacer region of the nuclear rDNA (ITS) sequences were used to demonstrate that, despite the extensive morphological and ecological diversity of the plants, the entire alliance in insular Macaronesia has a common origin. The sequence data place Lactucosonchus as

Genetic architecture may profoundly influence the ability of adaptive traits to spread between species via introgressive hybridization. Here, we examine the genomic location of quantitative trait loci (QTL) associated with pollen sterility and morphological traits distinguishing two annual sunflowers, Helianthus annuus and H. debilis ssp. cucumerifolius. These species are of particular interest since they hybridize naturally, and the form of H. annuus in Texas (called ssp. texanus) is thought to

The flora of Macaronesia, which encompasses five Atlantic archipelagos (Azores, Canaries, Madeira, Cape Verde, and Salvage), is exceptionally rich and diverse. Spectacular radiation of numerous endemic plant groups has made the Macaronesian islands an outstanding area for studies of evolution and speciation. Despite intensive investigation in the last 15 years, absolute age and rate of diversification are poorly known for the flora of Macaronesia. Here we report molecular divergence estimates an

Species belonging to <i>Rosa</i> section <i>Synstylae</i> (Rosaceae) are mainly distributed in East Asia, and represent recently diverged lineages within the genus. Over decades, inferring phylogenetic relationships within section <i>Synstylae</i> have been exceptional challenges, due to short branch lengths and low support values. Of approximately 36 species in the section <i>Synstylae</i>, <i>Rosa multiflora</i>, <i>Rosa luciae</i> and <i>Rosa maximowicziana</i> are widely distributed in the S

Sequences from the internal transcribed spacer region (ITS) of nuclear ribosomal DNA were used to assess relationships among genera of subtribe Sonchinae (Lactuceae). The data suggest that Sonchinae is paraphyletic, and that the Dendroseridinae should not be recognized as a distinct subtribe. Several Macaronesian genera, along with woody Macaronesian species of Sonchus (all diploid, 2n = 18), appear to have been derived from a common ancestor. Prenanthes pendula is more closely related to this M

Determining accurate phylogenetic relationships among the members of the woody Sonchus alliance presents challenges because of an insufficient level of molecular variation and the convergent evolution of similar morphological traits in island settings. To obtain a better resolved phylogeny and to test the potential role of hybridization and introgression, we sequenced all members of the alliance with multiple populations for the ITS of nrDNA and over 4000 base pairs of coding and noncoding regio

The Sonchus alliance represents an oceanic island radiation that includes six genera and 31 species of herbs, shrubs, and trees occurring in diverse habitats ranging from cool, upland cloud forests to hot, dry, exposed cliff faces and coastal deserts. To investigate the role of photosynthetic adaptations during radiation into diverse habitats, we measured leaf morphological and physiological traits and relationships among 15 representative species of the woody Sonchus alliance grown under unifor

Sequences from the internal transcribed spacer region of nuclear ribosomal DNA (ITS) for 35 taxa of Coreopsis and 15 species of Bidens were used to hypothesize phylogenetic relationships within and between the two genera. Coreopsis is paraphyletic and Bidens is polyphyletic in all most parsimonious trees. The ITS phylogeny indicates that the Bidens-Coreopsis complex originated in Mexico with subsequent primary radiations to North and South America. The molecular data suggest that Bidens as now r

The contribution of epistasis to 15 morphological traits differentiating two annual sunflowers (Helianthus annuus and H. debilis ssp. cucumerifolius) and to hybrid pollen sterility was estimated in a first generation backcross (BC1) mapping population. Analysis of digenic interactions among quantitative trait loci (QTLs) with significant main effects revealed significant interaction effects for six of the 15 morphological traits and for pollen sterility. Likewise, a genome-wide scan of all possi

The woody <i>Sonchus</i> alliance consists primarily of woody species of the genus <i>Sonchus</i> (subgenus <i>Dendrosonchus</i>; family Asteraceae). Most members of the alliance are endemic to the oceanic archipelagos in the phytogeographic region of Macaronesia. They display extensive morphological, ecological, and anatomical diversity, likely caused by the diverse habitats on islands and rapid adaptive radiation. As a premier example of adaptive radiation and insular woodiness of species ende