温度和盐度对浒苔生长和光合生理特性的影响

COMBINED EFFECTS OF SALINITY AND TEMPERATURE ON THE GROWTH AND PHOTOPHYSIOLOGICAL PERFORMANCES IN ULVA PROLIFERA

为研究海水盐度和温度对大型海藻光合生理影响的复合效应,选取浒苔(Ulva prolifera)为实验材料,探讨不同温度(22℃和15℃)和不同盐度(25和10)对浒苔的相对生长速率、色素含量、叶绿素荧光参数、超氧化物歧化酶(SOD)活性、可溶性蛋白含量等影响。结果表明:在低温条件下,盐度对浒苔生长的影响不显著,而在正常温度条件下,盐度降低显著降低了浒苔的生长;在低盐条件下,尽管差异不显著,温度降低呈现出促进浒苔生长的趋势,但在正常盐度条件下,低温降低了浒苔的生长。相对于温度变化,盐度变化对浒苔潜在的光合效率(F_v/F_m)影响不明显,但低温低盐处理下浒苔具有较高的效光化学效率(F_v′/F_m′)、光能利用效率(α)、非光化学淬灭(NPQ)、SOD酶活性及可溶性蛋白含量。

The tidal influence, monsoon, freshwater inputs and other environmental factors impact temperature and salinity in tidal zone where the macroalgae grown. The current study evaluated effects of temperature and salinity on the growth and photophysiological performance of macroalgae. Ulva prolifera were cultured in 4 conditions including the ambient condition（22 and 25 salinity）, normal temperature and low salinity（22 and 15 salinity）, low temperature and normal salinity（15 and 25 salinity） and low temperature and low salinity（15 and 15 salinity） for 6 days to measure the growth, chlorophyll content, chlorophyll fluorescence parameters, SOD activity and soluble protein content. Our results showed that temperature did not impact the growth of U. prolifera at low temperature, and that low salinity decreased the growth of U. prolifera at normal temperature, and that temperature slightly but not significantly mediated the growth of U. prolifera at low salinity, and that low temperature significantly reduced the growth of U. prolifera at normal salinity. Temperature but not salinity significantly impact the F_v/F_m. U. prolifera cultured in low temperature and low salinity condition showed higher F_v′/F_m′, NPQ, SOD activity and soluble protein content.