红树植物秋茄叶片水提物的抑藻效应: Inhibitory effects of aqueous extracts from mangrove plant Kandelia candel leaves on microalgae

Through the measurement of algal cell density, this paper evaluated the allelopathic inhibitory effects of different concentration (0. 5, 1.0, and 2. 0 g · L -1) aqueous extracts from the fresh leaves of mangrove plant Kandelia candel on Phaeocystis globosa and Heterosigma akashiwo. The impacts of heat treatment on the allelopathic effects of the extracts were also examined. The leaf extracts of K. candel had significant inhibitory effects on the two microalgae, and the effects were concentration-dependent. In five days, the maximum inhibitory rates of the extracts at 2. 0 g·L -1 on P. globosa and H. akashiwo were 91. 6% and 77. 0%, respectively. P. globosa and H. akashiwo had different sensitivity to the extracts. The inhibitory effect of the extracts was stronger on P. globosa than on H. akashiwo. Heat treatment decreased the inhibitory effects of the extracts significantly (P<0. 05). The extracts damaged the cell membrane of the microalgae, making their cells expanded and broken.