Release of Phosphate from Soil Minerals by Hydrogen Sulphide

Abstract

IN this laboratory it was observed that some colonies of soil bacteria and fungi, grown on carrot-extract agar containing 0.1 per cent ferric phosphate in suspension, turned the particles of phosphate in their vicinity black. Blackening occurred only when hydrogen sulphide, was produced by these organisms, some of which formed it anaerobically but others aerobically. Bromfield1 showed that hydrogen sulphide was produced by several strains of Bacillus megatterium in apparently well-aerated...