Zinc Fertilizer Solubility and Its Effects on Zinc Bioailability Over Time

Abstract

Studies have found that low water-soluble zinc (Zn) sources are not as effective in supplying Zn for plant use as highly water soluble ZnSO 4 ·2H 2 O. However, there is a question as to the residual effects of Zn from low water-soluble fertilizers on subsequent crops. The objective of this greenhouse study was to determine the relationship between water solubility of Zn fertilizers and Zn availability over four cropping periods. Three Zn fertilizers with 99.7, 56.0, and 6.0% water solubility were evaluated at rates equivalent to 0, 5, 10, 15, and 20 kg Zn ha −1 . Four consecutive corn (Zea mays, L.) crops were grown in pots to the V-10 growth stage to determine Zn residual effects. Zinc fertilizer was only applied to the first crop, requiring subsequent corn crops to use residual Zn for nutrient needs. Results show that Zn sources with medium and low water solubility did not become more available over time, nor did they supply enough Zn to meet the crop's needs. The highly water-soluble source was effective in supplying Zn for two crops, after which plants showed Zn deficiencies. Zinc fertilizers of low solubility do not increase plant-available Zn over time. These results complement our previous research, and support the conclusion that Zn fertilizers of low water solubility are ineffective Zn sources for corn.

Selecting Zinc‐Efficient Wheat Genotypes with High Grain Yield Using a Stress Tolerance Index

“…Adding more fertilizer to maintain a sufficient level of available Zn will increase total content in soil. Increased total soil Zn may create problems of Zn toxicity for crops in the future, especially if land use should be changed or when soil should become relocated, e.g., by erosion, and then subjected to conditions that result in Zn mobilization (Brennan and Bolland 2006; Shaver et al, 2007).…”

Effect of copper carbonate and zinc oxide applied to seeds on copper and zinc uptake by maize seedlings

“…These sources generally differ in terms of water solubility, which is an important parameter that determines their uptake by plants (Amrani et al 1999;Shaver et al 2007;Salanenka and Taylor 2011). Prado et al (2007) compared two sources of zinc for maize seed treatment -zinc sulphate (water-soluble) and zinc oxide (water-insoluble) -and verified that the first is able to promote a higher uptake of zinc by plants.…”

Influence of Moisture Conditions on Residual Zn Concentrations Applied as Synthetic Chelates

“…The availability of this applied amount depends, among other factors, on the source applied (Shaver, Westfall, and Ronaghi 2007) or on the soil properties; for example, in calcareous soils the presence of hydroxides and carbonates can produce low availability (Alloway 2005). Zinc chelates provide this micronutrient to produce high concentrations of water-soluble Zn and available Zn in soils, though the effectiveness of these chelates depends on their stability.…”