By Faridat Salifu
Drought and rising temperatures can expose nutrient deficiencies that remain hidden in crops under normal growing conditions, making balanced soil nutrition increasingly important for maintaining yields during periods of environmental stress.
The Potash Development Association said crops may continue to produce acceptable yields even as soil nutrient reserves gradually decline, with deficiencies becoming more apparent when plants face prolonged dry conditions.
Potassium deficiency is a particular concern because it is not always visually obvious.
A crop growing on soil with adequate potassium reserves and another growing on soil where nutrient removal has exceeded replacement may perform similarly under favourable conditions.
However, during a prolonged dry spring, the potassium-deficient crop is more likely to experience earlier problems with stomatal function, water regulation and photosynthesis.
Potassium plays an important role in how crops manage water, making adequate supply particularly important when soil moisture becomes limited.
The effects of nutrient deficiencies can become even more significant when crops are exposed to intense sunshine and high temperatures.
Magnesium, for instance, is essential for efficient photosynthesis and helps crops capture and utilise available light energy.
A shortage can also restrict the movement of carbohydrates from leaves to developing grain or other storage organs.
Bright sunshine combined with dry soils has been observed to increase the expression of magnesium deficiency symptoms, particularly on lighter-textured soils.
Maintaining adequate magnesium levels can therefore help crops sustain performance during stressful growing conditions.
Sulphur is another nutrient that can become critical when crops are under pressure.
It contributes to protein synthesis, enzyme activity and efficient nitrogen utilisation, meaning sulphur-deficient crops may struggle to make full use of available nitrogen.
This can restrict growth and development at a time when plants need to maintain efficient metabolic activity to withstand environmental stress.
Calcium also supports crop resilience through its role in cell wall formation, membrane stability and root development.
Healthy and extensive root systems are particularly important during drought because they allow crops to explore more soil for water and nutrients.
While potassium is closely linked to drought resilience, the association said protecting crops from environmental stress cannot depend on a single nutrient.
Maintaining a balanced supply of potassium, magnesium, sulphur, calcium and other essential nutrients can strengthen crop development and improve the ability of plants to cope when drought, heat and intense sunlight combine.
As dry conditions increasingly test crop performance, maintaining soil fertility could therefore be as important to resilience as responding to drought once it occurs.
