Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi-110 012, India
*Present address: Indian Institute of Horticultural Research, Hessaraghatta Lake P.O., Bangalore - 560 089, Karnatka State, India
**For correspondence
Online published on 3 November, 2011.
The regression equations obtained during the quantitative structure-activity relationship studies of 0, 0-bisaryl isopropyl phosphonates for their fungitoxicity to Pyricularia oryzae, and Alternaria alternata asing garious steric parameters are presented. Steric bulk of the substituent at the para position of the phenyl ring involved in the intermolecular interaction with the bioreceptor was better modelled by molar refractivity than Taft's and sterimol parameters. Among sterimol parameters, B4 (denoting maximum width) gave a better correlation than L, BI and 82 against both the fungi.
Molar refractivity, organo phosphonate, fungicide, modelling
