Bioassays of Fenazaquin 18.3% w/w (200 SC) against Two Spotted Spider Mite, Tetranychus urticae Koch (Acari: Tetranychidae): Effect of Test Method, Exposure Period and Mortality Criterion on the Precision of Response Estimates
Priyadharshini V. *
Department of Entomology, Toxicology Laboratory, Faculty of Agriculture, Annamalai University, Chidambaram – 608 002, Tamil Nadu, India.
Ayyasamy R.
Department of Entomology, Toxicology Laboratory, Faculty of Agriculture, Annamalai University, Chidambaram – 608 002, Tamil Nadu, India.
Kathirvelu C.
Department of Entomology, Toxicology Laboratory, Faculty of Agriculture, Annamalai University, Chidambaram – 608 002, Tamil Nadu, India.
*Author to whom correspondence should be addressed.
Abstract
Quinazoline class of pesticide fenazaquin 18.3% w/w (200 SC) (IUPAC name: 4-tert-butylphenethyl quinazolin-4-yl ether) is used to manage mites and insects by interfering with the biochemistry of the pests' mitochondria. Three different bioassay methods viz., leaf dip, slide dip, and residual film were evaluated using fenazaquin 18.3% w/w (200 SC) at various doses on adults of Tetranychus urticae along with two standard checks (fenazaquin 10 EC and spiromesifen 22.90% SC) and water as control. After 24 h of exposure, fenazaquin 18.3% w/w (200 SC) @ 1.25 and 1.60 ml/l exhibited 100% mortality which was comparably higher than the standard checks. The results revealed that all the doses of fenazaquin 18.3% w/w (200 SC) were superior for the management of two spotted spider mites.
Keywords: Bioassays, fenazaquin 18.3% (200 SC), Tetranychus urticae, mortality