Author: C. K. Tseng and T. J. Chang
J Integr Plant Biol 1954, 3 (3): -.
1. Evidences are produced showing that carpospores of Porphyra tenera Kjellm. can give rise only to the
filamentous Conchocelis-stage. Development of "normal" Porpohyra thalli in carpospore cultures is due to
the presence of monospores mixed up in the same culture.
2. When water temperature reaches 15-17℃ or higher, Conchocelis gives rise to swollen cells which,
when mature, become asexual spores for which the name "conchospore" is proposed. Conchospores
germinate in the same manner as monospores and are expected to give rise to the normal leafy stage of
Porphyra.
3. Although there are as yet no experimental evidences, we believe, on the basis of our field observations,
that conchospores will give rise to the dwarf type of the leafy Porphyra when water temperature rises above
20-22℃., and to the normal leafy type, when water temperature drops down to lower than 20℃.
4. Dwarf Porphyra are only a few millimeters to 1-2 centimeters in diameter. They multiply by monospores
which are similar to, but much smaller than-those of the normal leafy Porphyra. It is believed that dwarf
Porphyra are merely side issues in the life history of Porhyra. It is possible, that in places where summer
water temperature is relatively low, say, lower than 17-20℃, the dwarf Porphyra stage may be entirely
eliminated.
5. The important constituents of the life history of Porphyra are the leafy stage (the ordinary Porphyra
thalli) giving rise, as a result of sexual reproduction, to carposporo, and the filamentous stage (the
Conchocelis) giving rise to conchospores.