3种环境因子对围氏马尾藻受精卵生长发育的影响

Effects of Three Environmental Factors on Development and Growth of Zygotes of Sargassum wightii

为探索围氏马尾藻(Sargassum withgii)受精卵生长发育的最适条件,研究不同温度(18、21、24、27、30℃)、照度(1 000、2 000、3 000、4 000 lx)和盐度(15、20、25、30、35、40)对围氏马尾藻受精卵成活率和幼孢子体生长的影响。结果表明:围氏马尾藻受精卵在21℃下成活率最高(89.3%),与其他温度组差异有统计学意义(P<0.05);受精卵在1 000 lx下的成活率最高,为89.3%,与其他照度组差异有统计学意义(P<0.05);受精卵对于盐度的适应范围较广,15~30的盐度组成活率均较高(>86.3%)。培养前10 d,21℃组的幼孢子体平均长度最大(P<0.05),15 d时24℃组平均长度超过其他温度组(P<0.05);在培养前15 d,1 000 lx照度组幼孢子体生长速度最快(P<0.05),20 d后3 000 lx组孢子体平均长度超过其他照度组(P<0.05);在15~30盐度范围内,幼孢子体均生长较好,且各盐度组间平均长度差异无统计学意义(P>0.05)。

To study the optimum temperatures, light intensity and salinity for the development and growth of zygotes of Sargassum withgii, the survival rate of zygotes and the growth of seedlings at different temperature (18, 21, 24, 27 and 30 ℃), light intensity (1000, 2000, 3000, and 4000 lx) and salinity (15, 20, 25, 30, 35 and 40) were researched. Results showed that the survival rate of fertilized eggs under 21 ℃ (89.3%) was significantly higher than that of other groups when cultured at different temperatures (P < 0.05); in the experiment of different light intensity, a significant higher survival rate(89.3%) was found at the group of 1 000 lx (P < 0.05); when cultured at different salinity the fertilized eggs have a higher mean survival rate (87.7%) under the range of 15 – 30 and with no significant difference with each other (P > 0.05). In the sporophytes growth experiments, the average length of the sporophytes under 21 ℃ was significantly longer than that of the other groups in the first 10 days of culture (P < 0.05); however, after that the mean length of the group under 24 ℃ was the longest. The average length of the sporophytes under 1000 lx was the longest in first 15 days (P < 0.05); while the mean length of group 3000 lx was significantly longer than that of the other groups after 15 days. And the sporophytes could develop well under the salinity of 15 – 30, and no significant difference in mean length under this range was found (P < 0.05).