IGS Seminar will be held as follows.

■ Date and time: Monday, December 19th, 10:00-11:30 JST
■ Venue: Online (ZOOM)/ Face to Face (School of Integrated Arts and Sciences, K204)
■ Lecturer:
Prof.Toshihiro Yamada; Graduate School of Integrated Sciences for Life, Hiroshima University
■ Language: English
■ Abstract: Phyllostachys nigra var. henonis is a monocarpic bamboo of which flowering interval is 120 years and it is predicted that the next flowering will occur in the 2020s in Japan. A huge area of Japanese land is now covered by P. nigra var. henonis stands. The die-back of P. nigra var. henonis stand and the drastic change in land cover after flowering may cause a serious social and/or environmental problem. However, at the last flowering event in the 1900s, no study on regeneration of this bamboo species was conducted and therefore the regeneration process of this species is still unknown. We encountered a reginal flowering of this bamboo species in 2020 in Japan. By exploiting this rare opportunity, we studied the initial regeneration process of this species. For three years, more than 80% culms in the study site bloomed. But no seed was produced. Also, we could not find any seedlings established. These facts strongly suggest that this species does not have ability to produce seeds and failed to sexual regeneration. After flowering, some bamboo culms were produced but they all died within one year after the emergence. This species formed small, weak culms (dwarf ramets) after flowering that did not appear before flowering. However, majority of dwarf ramets died within one year after emergence. In three years after flowering, all culms died, while no sign of regeneration was detected. Based on three years observation, this bamboo seems to be going extinct. However, this view is completely contradicted with the fact that this species lasted long in Japan. Finally, a possible regeneration mode of this species was discussed.