We present most comprehensive phylogenetic analysis of 196 accessions of Lilium representing 83 species and 14 varieties of Lilium and three outgroup genera (Cardiocrinum, Notholirion, and Fritillaria) to investigate infrageneric relationships within Lilium as well as to determine the origin and evolution of Korean species of Lilium. We used the internal transcribed spacer sequences of nuclear ribosomal DNA and phylogenetic analysis using maximum parsimony and Bayesian inference identified several major lineages within Lilium. Only one section, Martagon, turned out to be monophyletic in the study. Three sections, Archelirion, Liriotypus, and Pseudolirium, are not monophyletic because two, one, and two species in each section were placed in other lineage, respectively. Two major lineages of section Leucolirion were confirmed in this study, and as several previous studies suggested, section Sinomartagon is highly polyphyletic. The origin of Lilium hansonii, a Korean endemic to Ullung Island, is perplexing given the fact that it has ribotype of Martagon, while its cpDNA haplotype is similar to Sinomartagon. The origin of another endemic, Lilium amabile, is equally elusive and additional phylogenetic and phylogeographic studies will shed light on their evolutions in Korea. We determined that Lilium callosum var. flavum originated from L. callosum in Southern Korea.

To elucidate the evolution of epiphytes in Liparis section Liparis, we examined the phylogenetic relationships of 16 species by using internal transcribed spacer regions of 18S-26S nuclear ribosomal DNA (ITS) and three chloroplast DNA regions (trnS-trnG spacer, trnL with trnL-trnF spacer, and partial matK). Results showed that the epiphytic L. fujisanensis is sister to the terrestrial L. koreana and L. kumokiri, while another epiphyte, L. truncata, is sister to the terrestrial L. krameri. Therefore, the two epiphytic species evolved from terrestrial species independently in section Liparis. Comparative seed morphology revealed that the epiphytes have larger embryos than their closely related terrestrial counterparts. A similar trend toward the increase of embryo size in the two epiphytic species belonging to closely related, but distinct clades suggests that the large embryo may have an advantage in the epiphytic lifestyle. The two epiphytic species share another character state, smaller air spaces in the seed than that of closely related terrestrial species, suggesting possible low dispersibility of the epiphytes.

Eastern Asian‐eastern North American disjuncts in four genera were examined for allozyme divergence and sequence divergence of the internal transcribed spacers (ITS) of nuclear ribosomal DNA. The disjunct pairs of taxa include Caulophyllum robustum‐C. thalictroid.es, Menispermum dauricum‐M. canadense, Penthorum chinense‐P. sedoides, and Phryma leptostachya var. asiatica‐P. leptostachya var. leptostachya. Allozyme divergence was comparable in Caulophyllum and Penthorum (genetic identities of 0.534 and 0.546) and was considerably higher than between pairs of taxa in Menispermum (0.273) and Phryma (0.291). Caulophyllum and Penthorum, which have the highest genetic identities at allozyme loci, also have low ITS sequence divergences (1.30 and 1.65%, respectively). Phryma, which has low isozyme identity, also has the highest ITS sequence divergence (4.46%). The two taxa of Menispermum have low ITS sequence divergence (0.93%) despite having a low identity (0.273) at allozyme loci. The results suggest that divergence between the taxa in the four genera are not the result of a single historical event. Estimated divergence times are reasonably consistent with a late Miocene disjunction for Caulophyllum and Penthorum, whereas the age of the Phryma disjunction is calculated at over 20 million years. The nonconcordant divergences between allozymes and ITS sequences in Menispermum may be caused by concerted evolution in the latter or possibly longer generation time in the woody plants. Additional molecular data are needed to clarify the situation.

Santalales is a large order, with over 2200 species, most of which are root or aerial (stem) hemiparasites. In this study, we report the newly assembled chloroplast genome of Dendrotrophe varians (140,666 bp) in the family Amphorogynaceae and the cp genomes of Helixanthera parasitica (124,881 bp) and Macrosolen cochinchinensis (122,986 bp), both in the family Loranthaceae. We compared the cp genomes of 11 Santalales including eight currently available cp genomes. Santalales cp genomes are slightly or not reduced in size (119–147 kb), similar to other hemiparasitic species, when compared with typical angiosperm cp genomes (120–170 kb). In a phylogeny examining gene content, the NADH dehydrogenase gene group is the only one among eight functional gene groups that lost complete functionally in all examined Santalales. This supports the idea that the functional loss of ndh genes is the initial stage in the evolution of the plastome of parasitic plants, but the loss has occurred independently multiple times in angiosperms, while they are not found in some parasites. This suggests that the functional loss of ndh genes is not essential for the transition from autotroph to parasite. We additionally examined the correlation between gene content and type of parasitism (obligate/facultative and stem/root parasites) of all hemiparasitic species in which cp genomes have been reported to date. Correlation was not found in any types of parasitism.

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