不同环境因子对异枝江蓠的生长及生化组分的影响

Effects of various environmental factors on growth and biochemical components of Gracilaria bailinae

关键词:  异枝江蓠  温度  盐度  光照强度  生长  生化组分

Key words:  Gracilaria bailinae  Temperature  Salinity  Light intensity  Growth  Biochemical components

摘要:

分别测定了在不同温度（18、23、28、33、38℃）、不同盐度（13、18、23、28、33、38）和不同光强（3000、6000、9000、12000 lx）的培养条件下，异枝江蓠藻体的相对生长速率和生化组分的变化。实验结果表明，异枝江蓠适合生长温度为23-33℃，在此温度范围，藻体具有较高的相对生长速率(RGR)，其藻胆蛋白和可溶性蛋白的含量较高，过氧化物酶（POD）的活力较低。异枝江蓠适合生长的盐度为18-28，异枝江蓠对低盐的耐受能力高于高盐，6000 lx是异枝江蓠的最适生长光强。

Abstract:

Gracilaria bailinae, the genus Gracilaria, is a commercially important species of red seaweeds, and is currently farmed in the ponds along the coast of south China. It is commonly used as the food source in abalone aquaculture and employed for the extraction of agar as a raw material. However, the optimum growth conditions of G. bailinae are unclear. This study examined the physiochemical responses of G. bailinae to different levels of temperature, light and salinity to determine the suitable environmental conditions for the growth of G. bailinae. Thalli of G. bailinae were cultured under different conditions of temperatures (18℃, 23℃, 28℃, 33℃, and 38℃), salinities (13, 18, 23，28, 33, and 38), and light intensities (3000 lx, 6000 lx, 9000 lx, and 12000 lx), and then the growth and biochemical components of the algal thalli were measured. The results showed that the optimum temperature for the growth of G. bailinae is in the range of 23-33℃. Under this temperature range, G. bailinae exhibited higher relative growth rate, higher contents of soluble protein and phycobiliprotein, and lower activity of peroxidase compared with other temperatures. The optimum salinity for the growth of G. bailinae is between 18-28, and G. bailinae displayed a higher tolerance to low salinity than to high salinity. The optimum light intensity for the growth of G. bailinae is 6000 lx. These results suggest that it is essential to choose suitable sea area or pond and season for successful mariculture.