Synergistic insecticidal and acaricidal compsn. - contg. isoxathione and pyrethroid, esp. for control of cotton pests

摘要

Compsn. comprises isoxathione (I; O,O-diethyl-O-(5-phenyl isoxazol-3-yl)phosphorothioate) and a pyrethroid of formula (II): (R is H or cyano, R1 is 2,2-dimethyl-3-(2,2-dichloro- or dibromo -vinyl)cyclopropyl; 2,2-dimethyl-3-(2-methyl -1-propenyl) cyclopropyl or 1-(4-chlorophenyl) -1-isobutyl). Specifically (II) is cypermethrin (IIa); permethrin; deltamethrin and fenvalerate and the wt. ratio (II):(I) is 1-10000:10000. The usual application is 50-1000 g/hectare (I) and 1-100 g/hectare (II). The compsns. are esp. useful for protecting cotton against e.g. caterpillars, biting and sucking insects, red spiders etc. The compsn. has a significantly higher activity than either component used alone.