A molecular phylogenetic analysis of Trachelospermum (Apocynaceae; T. asiaticum, T. jasminoides var. pubescens and T. gracilipes var. liukiuense) in Japan was conducted using cpDNA and nrDNA nucleotide sequences. The cpDNA phylogeny did not agree with morphology-based taxonomy, whereas the ITS phylogenies agree with morphology. These results can be explained by chloroplast capture or incomplete lineage sorting. The molecular data also indicate sequence differentiation in T. gracilipes var. liukiuense between the Bonin and Ryukyu islands. Furthermore, in the ITS sequences of T. jasminoides var. pubescens, additive nucleotide sites were present in the substitution sites between T. asiaticum and T. jasminoides var. pubescens. The results support the possibility of natural hybridization between T. asiaticum and T. jasminoides var. pubescens.

View full abstract

Hybridization is a common phenomenon in many plant genera, and among them is the world's largest aquatic genus, Potamogeton (Potamogetonaceae) with about 69 species and 50 hybrids reported. Here we provide genetic insights into Potamogeton hybrids from China, where ten or more putative hybrids exist, of which eight have been genetically confirmed. In the study presented here, we verified the hybrid status and inferred the origins of three Potamogeton hybrids using molecular phylogenetic analyses of plastid (chloroplast) trnT-trnF and nuclear ITS sequence data sets that include previously published and newly generated data. The hybrids identified were: 1) P. ×inbaensis, a known hybrid from Japan; 2) a hybrid between P. perfoliatus s.l. and P. wrightii, and 3) a hybrid between tetraploid maternal P. distinctus and diploid paternal P. octandrus. Potamogeton ×inbaensis is reported from China for the first time, whereas the latter two hybrids are new to science.

View full abstract

To better understand variation in Tofieldia coccinea in Japan and Korea, we compared morphological findings with molecular phylogenetic analyses using regions of the plastids trnK, trnL and trnL-F plus the nuclear ITS region of 10 species and 19 samples of Tofieldia, including 10 samples of T. coccinea. Based on morphology, we recognized seven varieties of T. coccinea, var. coccinea, var. kondoi, var. gracilis, var. kiusiana, var. geibiensis, var. akkana and a new variety, var. dibotrya, with a panicle (dibotryum). According to the molecular phylogeny, T. coccinea vars. coccinea, kondoi, gracilis and akkana formed a clade with 57-62% bootstrap support; var. kiusiana and var. dibotrya were excluded from the clade. The topology supports our recognition of T. coccinea vars. kiusiana and dibotrya as distinct from var. gracilis, which is morphologically most similar. The molecular phylogeny also supports the inclusion of T. coccinea var.fauriei within var. kondoi. The name T. yoshiiana var. koreana (comb, nov.) should be used instead of T. yoshiiana var. kanwonensis.

View full abstract

A new, peloric form of Cymbidium nagifolium Masam., discovered within a population in Miyazaki Prefecture, southern Japan, is described. The peloric form can be categorized as Type B peloria where the labellum is replaced by a third petal resembling the lateral petals. The mutation may be widespread within the population, since three individuals from different locations had peloric flowers.

View full abstract