Chitose Honsho

Sequence analyses of the ITS regions and the matK gene for determining phylogenetic relationships of Diospyros kaki (persimmon) with other wild Diospyros (Ebenaceae) species

To elucidate the relationships among Diospyros kaki and species closely related in previous studies, the nuclear ribosomal internal transcribed spacer (ITS) DNA sequence and the chloroplast matK gene were sequenced and compared with those of nine Diospyros species from Thailand, four species from temperate regions, and one species of southern Africa, D. lycioides. Maximum parsimony, maximum likelihood, and neighbor joining analyses of the matK and ITS data sets revealed that D. kaki is closely related to two diploid species, D. oleifera and D. glandulosa. D. kaki, D. glandulosa, and D. oleifera were placed differently in the trees obtained from ITS and matK data sets, suggesting that hybridization and/or introgression may have occurred during the development of these species. D. kaki was not found to be closely related to D. ehretioides, a diploid species from Thailand. These results differed from a prior analysis of this genus performed with chloroplast DNA (cpDNA) restriction site mutations in 3.2- and 2.1-kb amplified sequences. The results supported Ng’s hypothesis that D. glandulosa and D. kaki may share a common ancestor. D. oleifera was also closely associated with D. kaki.

Relationships among Asian persimmon cultivars, astringent and non-astringent types

A molecular marker analysis for Asian persimmon cultivar relationships and pollination status was conducted with 496 amplified fragment length polymorphism (AFLP) markers and 146 cultivars of Asian origin. Cultivars from China, Korea, and Japan were evaluated for marker composition and pollination status, which strongly influences fruit characteristics. Separation of Chinese, Korean, and Japanese cultivar groups and pollination type by neighbor-joining clustering, multidimensional scaling, and STRUCTURE was only weakly supported and not genetically significant. Significant differences for cultivar origin and pollination status were found for analysis of molecular variance (AMOVA), but most of the variation was among cultivars, not classification groups. All of the cultivar groups were genetically similar at the molecular level with most polymorphism due to individual cultivar differences.