Boron deficiency

Boron deficiency is a non-infectious physiological disorder caused by an insufficient supply of boron in the soil or an inability of the plant to uptake this essential micronutrient. Unlike fungal or bacterial diseases, this condition is purely nutritional and affects metabolic processes within the plant.

This disorder impacts a wide range of crops, with corn being particularly sensitive during the reproductive stage. Boron is crucial for pollen tube germination, and its absence often results in poor kernel set, stunted cob development, and reduced grain yield.

Symptoms typically manifest as stunted growth of terminal buds, brittle leaf stems, and chlorosis in younger leaves. In many plants, necrotic spots appear on leaves and stems, and reproductive parts may shrivel or drop off entirely before reaching maturity.

Development and spread are often exacerbated by high soil pH (over-liming), prolonged drought conditions, and low organic matter content. Since boron has limited mobility within the plant, it cannot be translocated from older leaves to younger tissues, making the symptoms start at the growing points.

The economic impact of boron deficiency includes severe losses in both yield and quality. Preventive measures focus on precise soil testing, balancing soil pH, and applying boron-containing fertilizers through foliar sprays to ensure rapid uptake during the most vulnerable vegetative stages.