Quantitative Structure Activity Relationship Study for Nematicidal Activity of O,O-Diaryl O-2-Chloroethyl Phosphorothionates*

The quantitative structure activity relationship (QSAR) of a series of O,O-diaryl O-2-chloroethyl phosphorothionates and their nematicidal activity against Meloidogyne incognita was analysed using physico-chemical parameters of the molecules by means of multiple regression analysis. The electronic effect of ortho-substituents in benzene ring expressed as Swain-Lupton constant (F) along with steric parameters of para and ortho-substituents expressed either as STERIOMOL, B1(p) and B4(o) or as Molar Refractivity, MR(p) and MR (o) was the major determinant for the nematicidal activity of the compounds in test series.