为探究脆江蓠(Gracilaria chouae)生长的适宜光强和温度条件,设置10、15、20、25℃4个温度梯度和40、80、120、160、200μmol·m–2·s–15个光照强度梯度,对脆江蓠进行二因素多水平室内培养实验。结果表明：温度、光强及二者交互作用均对脆江蓠的生长产生极显著影响(P<0.01),温度为相对生长速率(RGR)的主要影响因子。在光强120μmol·m–2·s–1,温度20℃条件下,脆江蓠相对生长速率最高。光合色素含量随温度升高而升高,随光强增大先升后降,其中光强对藻红蛋白(PE)、叶绿素(Chla)含量的影响较大,温度对藻蓝蛋白(PC)、别藻蓝蛋白(APC)含量的影响较大。超氧化物歧化酶(SOD)含量随温度的降低和光强的升高而升高,主要受光照强度影响。丙二醛(MDA)含量随温度和光强的上升均呈先上升后下降的趋势,主要受温度影响。结论认为,脆江蓠生长最适条件为光强120μmol·m–2·s–1,温度20℃；在25℃高温下脆江蓠细胞受害程度较高；在40~120μmol·m–2·s–1光强范围内,提高光照强度可提高脆江蓠的抗逆性。%A two-factorial experiment was designed to study the effects of temperature (10, 15, 20, and 25℃) and light intensity (40, 80, 120, 160, and 200μmol·m–2·s–1) on the growth and biochemical composition of Gracilaria chouae. And the determination of the relative growth rate, photosynthetic pigment content, malondialdehyde (MDA) and supe-roxide dismutase (SOD) content and other indicators were carried out. The results showed that temperature, light inten-sity, and their interactions had significant effects on the growth of G. chouae, and the effects of temperature was greater than those of light intensity. A higher growth rate of G. chouae was observed at 120μmol·m–2·s–1 and 20℃. Under such condition, G. chouae could reach to the maximum growth rate of 0.038 g·g–1·d–1. In addition, both temperature and light intensity had significant effects on the chlorophyll a and phycobiliprotein of G. chouae. In general, the photosyn-thetic pigment contents of G. chouae increased with the rise of temperature, while it increased initially and then dropped down with the rise of light intensity. The contents of phycoerythrin (PE), phycocyanin (PC), allophycocyanin (APC), and chlorophyll a were 1.12 mg/g, 0.272 mg/g, 0.216 mg/g and 1.82mg/g separately when the light intensity was 120μmol·m–2·s–1 and temperature was 25℃. Temperature, light intensity, and their interactions had significant effects on the SOD and MDA contents of G. chouae. And the effect of temperature on the content of MDA was greater than that of light intensity. The MDA content of G. chouae increased initially and then dropped down with increating light intensity and temperature. The content of SOD increased with increasing temperature and light intensity. And light intensity was the main factor affecting the SOD content of G. chouae.
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