塔玛亚历山大藻对海产双壳类生命活动的影响

The effect of Alexandrium tamarense on life activity of bivalves

通过一种重要有毒赤潮藻———产麻痹性贝毒毒素PSP的塔玛亚历山大藻对几种海产双壳类主要发育阶段:受精卵、D形幼虫、眼点幼虫、稚贝、仔贝和成贝生命活动的影响研究,发现该藻对双壳类孵化率、存活率、运动能力、滤食率和生长都有影响,毒性效应与藻密度有明显的相关关系.该藻对受精卵的抑制作用在100个/cm3的密度下最显著,36h后孵化率仅为对照组的30%.进一步的逐项毒性筛选实验表明此毒性来源于藻液、藻细胞和细胞碎片,而与去藻过滤液、藻细胞内容物、标准毒素STX无关,由此可以证实塔玛亚历山大藻确能产生一类非PSP毒素,并与细胞表面的未知毒素相关.

The effects of a PSP producing dinoflagellate Alexandrium tamarense on marine bivalves at their several important life stages: egg, S-shape larva, eyespot larva, juvenile and adult, are studied. The results show that the hatching, survival, activity, filtration and growth are adversely affected by the alga and the impact is significant with the increased algal density. The inhibitory effect on egg hatching is most significant, which the hatching rate is only 30% of the control when exposed to the alga at 100 cells/cm^3 after 36 h. Further experiment shows that the algal culture, cells and cell fragments have the inhibitory effect, but no effect from the cell-free medium, cell contents and standard STX. The results indicate that the alga can produce unknown toxins, rather than PSP, associated with the cell surface.