锥状斯氏藻休眠孢囊萌发调控因子的实验室研究  

Laboratory studies on germination of Scrippsiella trochoidea resting cyst in different environmental conditions

作　　者：王朝晖[1] 张玉娟[1] 曹宇[1] 

机构地区：[1]暨南大学水生生物研究所,广东广州510632

出　　处：《热带海洋学报》2010年第3期93-96,共4页Journal of Tropical Oceanography

基　　金：国家自然科学基金项目(40773063);国家自然科学基金委员会-广东省人民政府自然科学联合基金(U0633006);广东省科技计划项目(2007B030200002)

摘　　要：锥状斯氏藻Scrippsiella trochoidea是一种常见赤潮种类,为了了解影响锥状斯氏藻孢囊萌发的内外在调控因子,在实验室条件下研究了不同温度(15、20和25℃)、储存温度(4、15、20和25℃)、储存时间(30和60d)、营养盐含量(N:500μg·L-1,P:74―1.5μg·L-1;P:74μg·L-1,N:100―10μg·L-1)以及缺氧对锥状斯氏藻休眠孢囊萌发的影响。锥状斯氏藻孢囊的强制性休眠期在15—25d,不同温度下孢囊最终萌发率差别不大,为75%―82%,但低温可减缓孢囊的萌发速度。高温(25℃)和长时间保存(30d以上),可导致萌发率明显降低。N、P营养盐对孢囊萌发影响不明显,缺氧和黑暗能完全抑制锥状斯氏藻的孢囊萌发。结果表明:锥状斯氏藻孢囊较短的强制性休眠期和高萌发率,使其孢囊在广东沿海全年各季节均具有一定的萌发能力,并造成该藻赤潮的循环发生;同时,当孢囊悬浮至溶氧丰富、光线合适的上层水体,才能促进孢囊大量萌发,从而引发赤潮。Scrippsiella trochoidea is a common bloom causative species and its blooms occur every year in the Daya Bay of the South China Sea. Excystment of S. trochoidea was studied under laboratory conditions at different temperatures （15, 20, 25℃）, storage temperature （4, 15, 20, 25℃）, storage period （30d, 60d）, nutrients （N： 500μg·L-1, p： 74-1.5μg·L-1; p： 74μg·L-1, N： 100-10μg·L-1） and anoxia. The purpose is to understand factors controlling the germination orS. trochoidea resting cysts. Results showed that the dormancy period for S. trochoidea resting cysts in this study was about 15-25d. There were no obvious differences in germination rate in three temperatures of 15, 20 and 25 ℃, and the final germination rates were from 75% to 82%. However, low temperature （15℃） postponed the occurrence of germination. The germination rates decreased when cysts were stored under high temperature （25 ℃） and long durations （over 30d）. Nutrient concentrations did not exert visible influences on germination. Anoxia and dark inhibited germination of S. trochoidea cyst completely. The results suggested that the short dor- mancy period and high germination rate of S. trochoidea cyst provided this species the ability to germinate in all seasons of the year in coastal areas of Guangdong province, and resulted in the repeated occurrence of its blooms in the given sea area. Mean- while, only when the benthic cysts were suspended to the upper water column, could massive germination occur and initiate the bloom.

关 键 词：锥状斯氏藻 休眠孢囊 萌发 环境条件 

分 类 号：Q178.53[生物学—水生生物学]