Developmental Studies on 0,0-Bis (2,4,5-Trichlorophenyl) Isopropyl Phosphonate: A Potential Fungicide

O, O-Bis (2,4, 5-trichlorophenyl) isopropyl phosphonate has been reported to have broad spectrum of fungicidal activity. A few developmental studies like fungitoxicity, phytotoxicity on O, O-bis (2, 4, 5-trichlorophenyl) isopropyl phosphonate were carried out. The compound has been found to be very active against three important phytopathogenic fungi of paddy viz. Pyricularia oryzae, Helminthosporium oryzae and Nigrospora oryzae. It does not inhibit the germination of paddy-even at a concentration of 1000 ppm. A comparison of structure- activity relationships on four analogous 0,0-bis (2,4,5- trichlorophenyl) alkyl phosphonates showed that steric bulk of the alkyl group has detrimental effect on the fungicidal activity.