Soil test for available zinc in acid soils of Venezuela
1997
Arriechi, E. | Ramirez, R.
Zinc (Zn) deficiencies have been identified in Venezuela with increasing frequency in recent years However, there are no established critical values for available Zn in the acid soils of this country. Greenhouse studies were initiated to evaluate five extractants, DTPA, DTPA-HCL, Na-EDTA, 0.1N hydrochloric acid (HCL), and Mehlich 1 to predict Zn availability in 14 acid soils with corn as the test crop. Significant and positive correlations were found between Zn extracted among the five extractants. Zinc extracted was not related with soil pH and organic matter content, but with the cation exchange capacity and clay content. The Na-EDTA extractant was found to be the most suitable as an indicator of Zn-deficient acid soils, the critical Zn value being 2.4 mg.kg-1.
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