Diagnosis of Zinc Deficiency

Zinc deficiency in crops can be diagnosed or predicted successfully using field observations, soil tests and/or plant analysis. Plant species and genotypes differ in their requirements for Zn, so the timing and method of diagnosis is critical. Using whole shoots of plants to diagnose Zn deficiency has been unreliable but specific plant parts (especially young leaves) are good indicators of the Zn status of a plant. Enzyme activities have the potential to be developed into useful diagnostic tests of Zn deficiency. Many chemical extractants have been used to assess the Zn status of soils. These soil tests have often been improved by including measurements of other soil properties (e.g. pH, clay, organic carbon). However, there is a need to standardize the procedures which measure both the quantity and intensity of Zn.