Although NH
4+ fertilization is known to acidify rhizosphere and enhance nutrient uptake, the effects on a nutrient-sufficient acidic soil amended with lime are not demonstrated. Thus, the influence of NH
4+ fertilization of an unlimed and limed (3 g calcium carbonate per kg soil) acidic soil on the nutrient uptake and growth of maize was studied in comparison to NH
4NO
3 fertilization. The pH of limed rhizosphere soil was about two units higher than that of the unlimed soil. The maize plants were grown in pots under greenhouse conditions for about two months. The results showed that the pH of the NH
4+-fertilized unlimed and limed soil was 0.54 and 0.15 units lower than the NH
4NO
3-fertilized soil. Liming negatively affected shoot and root dry matter production, whereas the NH
4+-fertilized plants produced higher dry matter than the NH
4NO
3-fertilized plants, with significant difference of 28% in the limed soil only. Liming decreased Fe concentration in rhizosphere soil from 99 to 69 mg kg
−1 and decreased plant-available Mn the most (71%), whereas the NH
4+-fertilized unlimed and limed soil had 48% and 21% higher Mn concentration than the respective NH
4NO
3-fertilized soils. Similarly limed rhizosphere soil had 50% lower plant-available Zn concentration than the unlimed soil, and the NH
4+-fertilized soil had an 8% higher Zn concentration than the NH
4NO
3-fertilized unlimed soil. The liming negatively affected P, K, Mn, and Zn concentrations and contents in maize shoot to a lower degree in the NH
4+-fertilized soil, whereas the positive effect of NH
4+ on the nutrient concentration and contents was vigorous in the unlimed soil than the limed soil. It is concluded that NH
4+ fertilization could be beneficial in enhancing nutrient uptake and growth of maize in both acidic and alkaline soils, despite the higher inherent plant-available concentrations of the nutrient in soil.
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