HAN Wen-jun1, XU Yan-ting1, JIANG Yang-yang1, YAO Ya-nan1, CAO Xue-bing2, JIANG Ai-li1, CHEN Li-hong1, XING Rong-lian1*
1.School of Life Science, Yantai University, Yantai 264005, China；2. National Research Center of Algae and Sea Cucumber Engineering Technology, Shandong Oriental Ocean Science and Technology Company Limited, Yantai 264003, China
Abstract: Growth and maximal photosynthetic quantum yield (Fv/Fm) were investigated in filamentous green alga, Chaetomorphavalida, in culture medium containing various N/P of 8∶1, 16∶1, 40∶1, 80∶1 and 120∶1 prepared by sole source of nitrogen, NH4Cl, at a salinity of 24, 28, 30, 32, 34, 36, and 40, and pH value of 6.5, 7.0, 7.5, 8.0, and 8.5 at water temperature of 25 ℃ by single factor and orthogonal experiments. The single factor experiment showed that the specific growth rate (SGR) of the alga was very significantly influenced by the N/P ratio and pH (P<0.01), with the best N/P ratio of 8∶1 and 16∶1 for SGR, and high N/P ratio restraining the growth of the alga.The suitable range of salinity for the growth was shown to be varied from 28 to 34, unsuitable for growth at high and low salinity, with significant effect of salinity on photosynthesis of the alga (P>0.05). The suitable growth of SGR was observed at pH varying from 7.5 to 8.5, with increase in SGR at pH of 28-34, and without significant effect of other pH values on growth of the alga, except for pH 6.5 (P>0. 05). Orthogonal experiment showed that there were significant interactions between N/P ratio and pH, between N/P ratio and pH, and between salinity and pH on SGR of thealga (P<0. 01). The findings indicated that best growth, even explosive growth of Chaetomorpha valida was under the conditions of salinity of 34, pH 9.0, and N/P ratio 8∶1.
2019, Vol. 34 
