植物地理・分類学会 = The Society for the Study of Phytogeography and Taxonomy
Abstract
The reproductive characteristic of Hibiscus makinoi Jotani et H. Ohba and H. mutabilis L.（Malvaceae）was studied in Nagasaki Prefecture, Kyushu, southwestern Japan. The former is distributed from the Ryukyu Islands to western Kyushu of Japan and the latter is widely cultivated and sometimes found escaped in natural habitats in western Japan. Compared with H. mutabilis, H. makinoi is delayed about a month in the phenology of flower production. Hibiscus makinoi produced flowers from late September to late October and H. mutabilis from middle or late August to late September. Hibiscus mutabilis was pollinated by Lepidoptera, mainly Cehonodes hylas and Coleoptera such as Oxycetonia jucunda. However, pollinators rarely visited flowers of H. makinoi. This may be due to the late flower season. Pollination experiments with the following four treatments were done : open pollination, autonomous self-pollination, hand self-pollination and hand cross-pollination. The results of fruits set and seed sets indicated that these two Hibiscus species strictly avoid self pollination but are clearly self-compatible
