Determination of Plant-available Soil Manganese

Estimation of soil Mn availability has challenged soil scientists since yield increases from Mn fertilization were first demonstrated over 70 years ago. Early recognition of the important contributions of the different fractions of soil Mn to available supplies gave impetus to the work, and many researches and several comprehensive reviews have been published (For reviews see 11, 14, 16, 17, 23, 25, 38, 49, 51, 52, 61, 68, 112, 115). There is yet little agreement as to methods of analysis and their interpretation, or even whether useful prediction of the Mn status of a crop from measurable soil characteristics is possible.