紅藻シマチスジノリの室内培養

Abstract

The freshwater red alga Thorea gaudichaudii C. Ag. is found in a few springs in Okinawa Island. The culture studies of this alga were carried out in laboratory. The materials were collected from Kunigami-mura in southern region of Okinawa Island. Monospores liberated from field plants were germinated immediately and developed into prostrate filamentous thalli. This prostrate thallus produced many erect branches which grew into a densely branched tuft, so-called Chantransia-stage. Erect fronds arose from well-branched parts of the Chantransia-tuft and they developed into Thorea plants. In 6 months culture from monospore germlings, the erect fronds attained to about 15cm in length. The monosporangia were formed on fronds cultured under various temperatures ranging from 15 to 25℃. The sexual organs such as spermatangia, trichogynes and carposporangia were produced at warm temperatures of 22-25℃. From the observations on field-collected and cultured materials, this alga seems to be monoecious. The short cut fragments of prostrate branchlets and assimilatory filaments regenerated in tap water and finally developed to young erect plants.