MOLYBDENUM

Considering Mo’s importance in optimizing plant growth, it’s fortunate that Mo deficiencies are relatively rare in most agricultural cropping areas.

Deficiency Symptoms

Molybdenum-deficiency symptoms show up as a general yellowing and stunting of the plant. A Mo deficiency can also cause marginal scorching and cupping or rolling of leaves.

Usage

Several materials supply Mo and can be mixed with nitrogen (N), phosphorus (P) and potassium (K) fertilizers applied as foliar sprays or used as a seed treatment. Seed treatment is the most common way of correcting Mo deficiency because of the very small amounts of the nutrient required.

MoO₄⁻² Anion

Plants take up Mo as the MoO₄⁻² anion

Soil pH to Molybdenum Ratio

Molybdenum becomes more available as soil pH goes up, the opposite of most other micronutrients.

Toxicity

Excessive Mo is toxic, especially to grazing animals.

Molybdenum deficiency symptoms

Symptoms of deficiency can vary across crop species, but similarities exist for how nutrient insufficiency impacts plant tissue color and appearance. Nutrient deficiencies are commonly associated with the physical location on the plant (i.e., whether the symptoms are primarily observed on older versus newly formed plant tissue), but these symptoms can spread as the severity of the deficiency progresses.