| 研究実績の概要 |
Surveys and sample collections were carried out in Thailand and Malaysia. In 2020, a new collaboration with the Universiti Malayasia, Sarawak, was started. In addition to samples from wild taro (C. esculenta), samples were obtained from C. fallax, C. lihengiae, C. oresbia, and C. spongifolia (sp. nova). With these, selected nuclear and chloroplast genome loci were sequenced (2019-2020), revealing: (i) a possible western-eastern Sundaland divide in the genetic diversity of wild taro (C. esculenta), (ii) natural wild taro populations in a vast karstic region located in northern Vietnam and southern China, and (iii) apparent hybrids between taro and other Colocasia species.
In 2020, DNA analysis was extended to include full chloroplast genome sequences from multiple Colocasia species, providing a strong new phylogenetic model for the genus. This shows that taro (C. esculenta) is a polyphyletic taxon in terms of plastid genetic diversity, a finding that has major implications for the evolution and taxonomy of wild and cultivated forms of taro. This and our survey results point to the need for deeper study of the nuclear genome in Colocasia species. In a new collaboration with the Graduate School of Bioagricultural Sciences, Nagoya University (2020), a pilot HPLC experiment was carried out to observe some of the chemical diversity present in wild Colocasia species. This work suggests a possible focus for the study of nuclear genome diversity in taro: relationships between chemical ecology, plant signals, and domestication history.
|
