PHYTOTOXICITY CAUSED BY PEROXIDIZING HERBICIDES IS ALLEVIATED BY 2-SUBSTITUTED 4,6-BIS(ETHYLAMINO)-1,3,5-TRIAZINES

The effects of 2-substituted 4,6-bis(ethylamino)-1,3,5-triazines on ph ytotoxic activities caused by peroxidizing herbicides were investigate d using the autotrophic unicellular green microalgae Scenedesmus acutu s. Alleviation of phytotoxic activities caused by oxyfluorfen or chlor ophthalim, the so-called ''diuron effect,'' was observed by the simult aneous addition of 2-substituted 4,6-bis(ethylamino)-1,3, 5-triazines. Chlorophyll decrease, short-chain hydrocarbon formation and protoporp hyrin-IX (Proto-IX) accumulation in the cells were alleviated. The deg ree of alleviation of peroxidation correlated with the inhibitory acti vity of the 1,3,5-triazines on photosynthetic electron transport (PET) .