Page 39 - Nutrient Management Planning Guide

35

Chapter 2.1

Table 2.1.3 summarizes key characteristics of each of the essential micronutrients.

Table 2.1.3 Summary of Plant Micronutrient Characteristics

Micronutrient

Form Taken up by Plant

Function in Plants Comments

Chlorine (Cl) Cl - ion

Associated with the suppression of leaf and root diseases.

Added to soil when potash (KCl) is applied.

Iron (Fe) Fe 2+ /Fe 3+ ion

A vital constituent of chlorophyll. Important for oxygen transfer within the plant system. Important for the formation/ activity of respiratory enzymes.

Deficiency not observed in Alberta field crops, but common in trees, shrubs and ornamentals in southern Alberta.

Manganese (Mn)

Mn 2+ and as a component of organic complexes

Seems to play a role in the uptake of other nutrients and the activation of a number of enzyme systems.

Mn toxicity more common than deficiency.

Zinc (Zn)

Zn 2+ and as a component of organic complexes

Plays a role in the formation of growth promoting compounds, carbohydrate transformations, regulation of sugar consumption, and is a constituent of several enzyme systems.

Deficiencies are most likely on calcareous, light textured, high pH soils that are high in P content.

Boron (B)

Primarily boric acid (H

3

BO

3

)

Maintains plant cell wall integrity. Deficiencies suspected in some canola

crops grown in Alberta.

Copper (Cu)

Cu 2+ and as a component of organic complexes

Essential for production of Fe-containing compounds.

Facilitates synthesis of chlorophyll. Influences several metabolic reactions.

Coarse-textured black soils are often associated with deficiency.

Molybdenum (Mo) MoO

4

2-

Enhance plant uptake of N, K, and Ca required by legumes for fixation of atmospheric N by nodular bacteria. Assists in making Fe plant available.

Minimal evidence of confirmed Mo deficiencies in western Canadian field crops.