Natural occurrence of buff and tan mutants of Aspergillus fumigatus in Indian alkaline soils

Abstract

Buff and tan mutants of Aspergillus fumigatus were found to form part of the natural microflora of Indian 'usar' (alkaline) soils (pH 7.5–10.0). It appears that the two mutants arose as a result of the rigorous physical conditions prevailing in these largely denuded soils where the surface layers are subject to intensely high solar radiations. In view of their natural occurrence, separate taxonomic recognition is advocated for these forms.