有机磷农药对海洋微藻致毒性的生物学研究Ⅰ．四种海洋微藻对久效磷的耐受力与其SOD活性的相关性

Biologioal Studies of the Toxicity of Organophosphorus Pesticides on Marine MicroalgaesⅠ.The Relations between the Activity of Superoxide Dismutase and Monocrotophos Tolerance in Four Marine Microalgaes

本文研究了久效磷农药对扁藻、三角褐指藻、金藻和盐藻的毒性实验。结果表明，四种海洋微藻对久效磷的耐受力依次为：盐藻＞三角褐指藻＞金藻＞扁澡。对微藻细胞内过氧化物歧化酶（ＳＯＤ）活性的测定表明，四种海洋微藻对久效磷的耐受力与其ＳＯＤ活性具相关性，耐受力最强的盐藻其细胞内ＳＯＤ活性较高，并在久效磷的胁迫下保持相对稳定；耐受力较弱的三角褐指藻和金藻其细胞内ＳＯＤ活性随着久效磷浓度的提高逐渐下降；而耐受力弱的扁藻在久效磷胁迫下，其细胞内ＳＯＤ活性迅速下降。因此，可从ＳＯＤ活性及其变化规律上判断久效磷对海洋环境污染的程度以及海洋微藻的耐受力。

Four species of marine microalgae were cultured in various concentratiOns of monocro-tophos for 72 hours.The relative growth rate and SOD activity were tested.The results indicatedthat the most sensitive one to monocrotophos toxicity was Platymonas sp.,its SOD activity de-creased fastly under monocrotophos stress;the following were Diratens sp.and Plaeodectylumtricornutum Bull.,their SOD activities decreased slowly under monocrotophos stress,The toler-ance of Dunaliella Sallna to monocrotophos was the strongest among them,Its SOD activity washigher and sustained stable higher levels on the process of monocrotophos stress. Therefore,wecan regard the SOD activity of microalgaes as a sensitive biological index to detect marine pollu-tion resulted from monocrotophos.