Lanping Ding, Jing Yan, Yao Zhang, Bingxin Huang, Junxia Liang, Youxuan Guo, Yue Chu
Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin 300387, China
The marine green alga Codium fragile has attracted much attention due to its high economic and nutritional values. The light intensity and artificial aeration affect its growth and photosynthetic activity, which in turn affect its economic and nutritional values. The light intensities (30μmol·m-2·s-1, 60μmol·m-2·s-1, 90 μmol·m-2·s-1) and aeration regulation were investigated to the effect on the growth and photosynthetic physiology of C. fragile collected from the Bohai Sea, China. The results showed that the maximal photochemical efficiency of PSII (Fv/Fm) and photochemical quenching coefficient (qP) were highly significantly affected by different light intensities, and the non-photochemical quenching coefficient (NPQ) was significantly affected. They all decreased the least under 60μmol·m-2·s-1. The increase in the relative growth rate（RGR） of C. fragile during aeration was greater than that of the non-aeration group. At the same time, the Fv/Fm and qP decreased less than those of the non-aeration group. It shows that the aeration regulation had highly significant effect on the wet weight, Fv/Fm and qP of C. fragile. Among the six groups, only aeration and light intensities of 60 and 90μmol·m-2·s-1 were suitable for the growth of C. fragile, because the Fv/Fm decreased less and the qP increased. The result showed that the Fv/Fm and qP of C. fragile was significantly affected by the interaction of the two environmental factors, while the wet weight and NPQ was no significantly affected.