Ecology, Environment and Conservation Paper

EFFECT OF NITROPHENOIS ON GROWTH AND HEITEFOTROPHIC NITRIFICATION IN SOIL ISOLATES OF ASPERGILLUS SPP.

P. Madhavi Bharathi, P. Srilatha, M. Revathi and K. Venkateswarlu

Abstract

Four nitrophenols, viz., p-nitrophenol (NP), o-nitrophenol (ONP), m-nitrophenol (MN?) and 2,4- dinitrophenol (2,4-DNP), were assessed for their impact on growth, in terms of mycelial dry weight, and heterotrophic nitrification in three species of Aspergillus, isolated from soil. The selected nitrophenols were relatively less toxic toward heterotrophic nitrification mediated by Aspergillus spp. when compared with their toxicity on growth response of these isolates. Of the four nitrophenols, MNP was more toxic towards heterotrophic nitrification. The toxicity of the nitrophenols at effective concentrations (EC) ranging from 60 to 84 towards the three species at the end of 20 days, followed the increasing order: A. 'lavas> A. tamarii > A. fumigatus.