Differential sensitivity of two green algae, Scenedesmus quadricauda and Chlorella vulgaris, to 14 pesticide adjuvants

Growth-inhibition tests for 14 pesticide adjuvants which are widely used to manufacture various pesticidal formulations in China, were performed on the green algae Scenedesmus quadricauda, and Chlorella vulgaris to compare differential sensitivity among populations of these algae to the adjuvants. The results showed that the acute toxicities of 700musical sharp, 1601musical sharp, By-140, and SOPA to S. quadricauda and C. vulgaris were the lowest among all the tested adjuvants. The acute toxicities of Tween 80, O-25, and AEO-13 phosphate to the selected two green algae were intermediate among the tested adjuvants. The acute toxicities of 602musical sharp, 500musical sharp, OT, NP-10, OP-10, and JFC were the highest. Meanwhile, the algal species vary widely in their response to those adjuvants. The results showed that there was a differential response to various adjuvants among the selected algal species and that the sensitivities of the various algal species exposed to 1601musical sharp and OT varied by nearly 1 order and to 700musical sharp, and By-140 varied by over 1 order of magnitude. In addition, the NOEC and LOEC values of the selected 14 adjuvants to S. quadricauda and C. vulgaris were tested; the result showed that NOECless-than-or-equals, slantEC10