Phosphorus uptake suppression in maize seedlings as related to humate supply

The effect of sodium humate on phosphorus uptake by maize seedlings devoid of the endosperm was studied. Short-term experiments have shown that a suppression of phosphate ion absorption occurs under the described conditions in the presence of humate without decreasing the weight of experimental plants. The effect reported is delayed and is enhanced by prolonging the preliminary phase of starvation. It varies with the pH of the medium and reduces under extreme conditions the phosphate release from the root to the medium.