坛紫菜对赤潮异弯藻生长和光合活性的影响

以赤潮异弯藻为研究对象, 利用水样叶绿素荧光仪等研究新鲜坛紫菜、灭活坛紫菜、坛紫菜水溶性浸提液和甲醇提取物对有害赤潮微藻生长和光合活性的影响. 结果表明 新鲜坛紫菜具有抑制赤潮异弯藻的生长和光合活性(叶绿素a含量、光系统Ⅱ的最大光能转换效率和相对电子传递速率)的作用; 灭活坛紫菜(3.20g·L-1)、坛紫菜水溶性浸提液(0.80、1.60g·L-1)和甲醇提取物(3.20g·L-1)对赤潮异弯藻的生长和光合活性具有“先抑后促”作用. 坛紫菜水溶性浸提液(3.20 g·L-1)对赤潮异弯藻的生长和光合活性具有极显著抑制作用(P<0.01). 生长抑制作用大小为坛紫菜水溶性浸提液>灭活坛紫菜>新鲜坛紫菜>坛紫菜甲醇提取物, 坛紫菜可通过释放化感物质来抑制赤潮异弯藻的生长和光合活性, 且主要成分具有水溶性.

Effects of Pyropia haitanensis on growth and photosyntheticactivity of Heterosigma akashiwo

The effects of fresh Pyropia haitanensis, inactivated P. haitanensis, water-soluble extract and methanol extract of P. haitanensis on the growth and photosynthetic activity of Heterosigma akashiwo were studied using the chlorophyll fluorescence technology. Results showed that fresh P. haitanensis effectively inhibited the growth and photosynthetic activity of H. akashiwo (the content of chlorophyll a, maximal photochemical efficiency of photosystem Ⅱ and relative electron transport rate). Inactivated P. haitanensis (3.20 g·L-1), the water-soluble extracts (0.80, 1.60 g·L-1) and methanol extracts (3.20 g·L-1) of P. haitanensis presented “initial inhibition and subsequent promotion” on the growth and photosynthetic activity of H. akashiwo. The water-soluble extract of P. haitanensis (3.20 g·L-1) had a significant inhibitory effect on the growth and photosynthetic activity of H. akashiwo (P<0.01). The sequence of growth inhibitory effect was water-soluble extract > inactivated P. haitanensis > fresh P. haitanensis > methanol extract. The results indicates that P. haitanensis may inhibit the growth and photosynthetic activity of H. akashiwo by releasing water-soluble allelochemicals.