Elucidation of the phylogenetic relationships among <i>Alpinia</i> species native to the Nansei Islands, Japan

The Alpinia species (A. intermedia, A. zerumbet, A. formosana, A. uraiensis, and unidentified strains native to the Daito Islands), which are native to the Nansei Islands, Japan are ornamental plants that can be used as resources to produce seasonings and antibacterial and antiviral substances. Despite the usefulness of these plants, little scientific research has been conducted on their phylogenetic relationships. In this study, their phylogenetic relationships were examined based on genomic and chloroplast DNA polymorphisms, repetitive sequence abundance, and cytogenetic perspectives. The results indicated that A. formosana is most likely the outcome of a hybrid of A. zerumbet and A. intermedia, and the unidentified strains native to the Daito Islands are the outcomes of a hybrid of A. zerumbet and A. uraiensis. Immunostaining with a newly produced anti-centromere-specific histone H3 (CENH3) antibody revealed that the number of chromosomes in these species was 2n=48.