鼠尾藻幼孢子体培育条件探究

Cultural conditions for Sargassum thunbergii germlings

中文关键词: 鼠尾藻  幼孢子体  正交实验  营养盐水平  比生长速率

英文关键词: Sargassum thunbergii  Germlings  Orthogonal experiment  Nutrient level  Special growth rate

中文摘要:

      为探究鼠尾藻Sargassum thunbergii幼孢子体早期生长发育适宜的培养条件，设置了光照度、温度、盐度3个影响因素3个水平的正交实验，以及氮磷营养盐水平实验。结果表明，温度对鼠尾藻幼孢子体的生长影响最显著（P<0.05），25℃时幼孢子体比生长速率（SGR）有最大值10.78%，随着温度的降低，SGR逐渐降低；盐度对幼孢子体的SGR影响显著（P<0.05），盐度30时幼孢子体生长较快，盐度降低SGR也降低；光照度2 000～8 000lx对幼孢子体的生长影响不显著，SGR极差接近误差水平。氮磷营养盐水平对鼠尾藻幼孢子体的生长影响较大，实验用自然海水中氮素基本可以满足幼孢子体的需求，而磷元素相对缺乏。氮素加富条件下，氮磷比大于15:1时不利于幼孢子体的生长，适宜的氮磷比为10:1~2:1。结果表明，温度25℃、盐度30、光照度2 000lx是鼠尾藻幼孢子体早期生长发育适宜的条件。培养液氮素含量保持在0.45～1 mg/L，磷含量保持在0.3 mg/L左右有利于幼孢子体快速生长。

英文摘要:

      To determine the suitable cultural conditions for the growth and development of Sargassum thunbergii germlings, three factors (illumination, temperature, salinity, each with three levels) orthogonal experiments and the nutrients experiments were carried out. The results showed that temperature on the special growth rate (SGR) of S. thunbergii germlings is the most significant (P<0.05). The maximum value of SGR was 10.87% when temperature was 25℃. But the SGR decreased gradually as the temperature dropped. Effect of salinity on the germlings SGR was significant (P<0.05). The germlings grew faster when salinity was 30, whereas the SGR decreased as salinity reduced. Effect of illumination (2,000~8,000lx) on the SGR was not significant and the range of SGR was close to the error. Nitrogen and phosphorus nutrients levels had great influences on the SGR of S. thunbergii germlings. The nitrogen concentration of the natural seawater used in the experiments basically met the requirements of the germlings growth; however, the phosphorus was relatively lacking. When N/P over 15:1, it was adverse to germlings growth and the suitable ratio was about 10:1~2:1. In conclusion, temperature 25℃, salinity 30 and illumination 2000lx were the suitable cultural conditions for S. thunbergii germlings. Cultural medium with nitrogen concentration of 0.45~1 mg/L and phosphorus concentration of 0.3 mg/L was suitable to the growth of S. thunbergii germlings.