Influence of a pyrethroid insecticide on soil fungi

The selective effect of the pyrethroid insecticide (Polytrin) on soil fungi was studied at three doses when incorporated in soil or in agar or liquid medium. Polytrin induced an inhibitory effect on soil fungi after 2, 5 and 40 days when applied at certain levels and a stimulatory effect after 20 days of treatment with the high dose. When incorporated in the agar medium, Polytrin decreased the total counts of fungi, particularly, Aspergillus and Penicillium at the high dose (10.0 ppm). In liquid medium, it showed no significant effect except in case of A. terreus which was significantly enhanced by the three doses.