Availability of Cu, Zn and Mn in Soils: III.—Predictability of plant uptake

Abstract

Abstract The influence of various chemical soil fractions Of Cu, Zn and Mn in conjunction with plant uptake of any one or two of the elements on the variability of plant uptake of one of them was evaluated by correlation and regression analyses. Plant and soil data were obtained from divergent Wisconsin soils. Inclusion of Zn uptake and the HCl‐or EDTA‐extractable soil Cu fraction in the regression equation resulted in very high predictability of Cu uptake by oats. High predictability of Zn uptake was likewise realized by using the Mg(NO 3 ) 2 or DTP A soil Zn fraction along with plant Cu uptake as determinants. Manganese uptake was best predicted by using plant Zn uptake and Mg (NO 3 ) 2 ‐rextractable soil Mn as predictors. The extractant N ammonium acetate (pH 7)/0·01 M EDTA showed promise as a reliable soil test for predicting the concurrent plant availability of Cu, Zn and Mn in Wisconsin soils.