Effect of two insecticides, Sparkill (25% Cypermethrin) and Tafaban (48% Chorpyrifos) on mycobiota of maize plants in Upper Egypt

Abstract

Two insecticides, Sparkill (25% Cypermethrin) and Tafaban (48% Chlorpyifos) were used in the treatment of maize plants. At three different doses, both Sparkill and Tafaban were toxic to total and individual fungal population of rhizosphere and nonrhizosphere soil as well as to fungi inhabiting roots and foliage of maize. The most common fungal species comprised Alternaria alternata, Aspergillus flavus, A. fumigatus, A. niger, A. terreus and Emericella nidulans. The ability of different fungal isolates to produce extracellular enzymes in solid media was tested. The effect of both Sparkill and Tafaban (at 50-400 ppm) on mycelial growth and production of amylase, cellulase, lipase and protease by certain fungi was variable. In most cases the low doses were promotive whereas the high doses were depressive.