Relationship of Zinc Uptake by Corn and Sorghum to Soil Zinc Measured by Three Extractants

Abstract

Abstract Corn ( Zea mays L.) and sorghum ( Sorghum vulgare Pers.) plants were grown in a controlled environmental growth chamber in 12 medium‐ to coarse‐textured soils with two levels of Zn for each soil. These levels were the native amount in each soil and with 2.5 ppm added. After 4 weeks plants were harvested and Zn concentration and total Zn uptake were measured. Each soil was extracted with three different solutions: (i) 0.05 N HCl plus 0.025 N H 2 SO 4 , (ii) 0.1 N HCl, and (iii) 0.05 N EDTA at pH 7.0. Zinc uptake by the plants was correlated with the level of soil Zn determined by each extractant. The highest correlation was obtained for corn and sorghum with extractant (i). Correlation coefficients for corn for extractants (i), (ii), and (iii) were 0.89, 0.82, and 0.62, respectively. Correlation coefficients for sorghum for extractants (i), (ii), and (iii) were 0.70, 0.63, and 0.44, respectively.