Sometimes micronutrients are required in such small amounts, it is almost impossible to conceive the magnitude of their effect. Molybdenum is one of them.

Molybdenum is part of the enzyme that allows atmospheric nitrogen to be utilised in the soil. It is rarely measured in a soil test, but without 0.4 ppm in the soil there can be serious problems.
Nutri-Key Moly Shuttle™ allows foliar security – i.e., a foliar spray will cover a plant deficiency for a season if there is an unrecognised soil shortage of molybdenum