دراسة تأثير المبيدات العشبية (Igran ,Down-up ,Oxyfluofen) في نمو طحلب Senedesmus quadricuda بوجود بعض المركبات العضوية.

Abstract

The study was conducted to explore the relative sensitivities of Senedesmus quadricuda to three commonly used herbicide( Igran ,Oxyflufen 24% , dawn -up 48% )in different concentrations separated and in combination with three organic compounds ( ethanol 0.05% ,vitaminB2 .01mg/l and arginine 0.2mg/l ) . The toxicity of these herbicides was measured as a change in the cell count ( growth rate ) and in chlorophyll (a) content in cultures of the test organism. The results showed that, the toxicities of these three herbicides increased with exposure time as bellow (Oxyflufen 24% > Igran > dawn -up 48% ) in tested cultures while the density and chlorophyll (a) content of S. quadricuda was decreased. An addition of organic compound reversed the toxic effects of tested herbicides with arginin or vitaminB2 while an addition of ethanol didn't exhibit significantly any change in the toxicity of these herbicides.