Relative efficacy of different pesticides against red spider mite, Tetranychus cinnabarinus (Boisd.) (Acari: Tetranychidae)

The relative efficacy of eight pesticides namely diafenthiuron, dicofol, dimethoate, ethion, monocrotophos, oxydemeton methyl, propargite and sulphur studied against different developmental stages of red spider mite, Tetranychus cinnabarinus (Boisd.) through bioassays indicated that diafenthiuron, propargite, dicofol, monocrotophos, ethion and oxydemeton methyl were found respectively 1402.38, 361.35, 198.32, 20.31, 5.21 and 2.13 times more toxic than dimethoate against eggs. Sulphur did not show any ovicidal action. These pesticides and sulphur were more toxic than dimethoate against both the larval and nymphal stages of the mite. Regarding adulticidal action-diafenthiuron, propargite, dicofol, monocrotophos, ethion, oxydemeton methyl and sulphur were found respectively 516.43, 162.58, 60.45, 28.75, 6.76, 1.87 and 1.45 times more toxic than dimethoate. Diafenthiuron proved to be the most effective pesticide against different stages of the mite followed by propargite and dicofol. However, oxydemeton methyl and dimethoate were the least effective. Rest of the pesticides were moderate in their response.