STUDY ON JOINT ACTION OF PHENOLIC ACIDS AND UNSATURATED FATTY ACIDS TO MICROCYSTIS AERUGINOSA

Additive Index(AI) method and the semi-lethal dose index(SLDI) method were used to estimate the combined effects of allelochemicals(three phenolic acids and one unsaturated fatty acid) on Microcystis aeruginosa(M.aeruginosa).When allelochemicals were applied alone,the 72 h EC50 of catechol,pyrogallic acid,gallic acid and linoleic acid were 2.100,11.101,18.468 and 3.670 mg·L-1,respectively.According to the results of AI and SLDI,when allelochemicals mixed at equipotent concentrations,synergistic effect was found in the mixtures of catechol and pyrogallic acid,catechol and linoleic acid.And additive effect was found in other binary combinations.This research provided the foundation for further understanding the mode of allelopathic action between hydrophytes and algae.