Variations of photosynthetic activities in different tissue areas in Porphyra yezoensis thalli
条斑紫菜叶状体不同区域光合活性的研究

In this article, young thalli of Porphyra yezoensis were used to study carbon fixation and photosynthetic activities of the five parts from the basis to the top in the same thallus. The results indicated that: (1) there were variations of carbon fixation in different tissue areas, with the basis part possessing significantly the lowest carbon fixation while the part closing to the top the highest in the five parts; (2) photosynthetic activities and chlorophyll a contents were also different among tissue areas from the basis to the top, with the photosynthetic activities of the root and the top parts lower than the other parts and the contents of chlorophyll a showing a decrease tendency from the basis to the top. It has been reported that there was higher seeding regeneration in the excised fragment from the midst locations of P. yezoensis thalli. Our results revealed higher photosynthetic activities in the middle parts, suggesting a correlation between seeding regeneration and photosynthetic activities.