Role of solvent and emulsifier mixture in designing the toxicity of fenvalerate emulsion against larvae of Spodoptera litura (Fab.)

摘要

The effects of the solvent and emulsifier mixture on the toxicity of fenvalerate against nine-day-old, third instar larvae of S. litura were determined, along with the proprietary fenvalerate, under laboratory conditions. The treatments comprised ofxylene+aromex and xylene+toluene emulsified by Triton X-100 or Tween-80; and Triton X-100+Tween-80 (E1), Triton X-100+Swascofix DP-50 (E2) and Triton X-100+Teepol (E3) in aromex or xylene solvent. The toxicity of fenvalerate was highest (0.000137) whenformulated with xylene and toluene solvents emulsified with Tween-80. The emulsifier mixtures E1, E2 and E3 were more toxic than the proprietary fenvalerate by 5.35, 4.80 and 4.37-fold. E1+aromex was most toxic, whereas E3+aromex was the least toxic withLC50 values of 0.000155 and 0.000293, respectively.