Manganese deficiency

Manganese deficiency is a non-infectious physiological disorder that occurs when plants cannot access sufficient manganese from the soil. Since it is not a pathogen-based disease, it involves systemic metabolic failure, primarily disrupting photosynthesis and the activation of enzymes necessary for protein synthesis and plant growth.

This disorder affects a broad range of crops across different climatic zones. Corn is highly sensitive to manganese levels, often showing stunted development when the element is unavailable. Other susceptible crops include small grains, soybeans, potatoes, and various legumes, all of which rely on this trace element for optimal chlorophyll production.

The primary symptom is interveinal chlorosis, where the leaves become pale yellow while the veins remain green. In corn, this manifests as chlorotic streaking. As the deficiency progresses, affected areas may turn brown or necrotic, leading to leaf curling and significant stunting, which drastically reduces the plant's photosynthetic capacity.

Conditions that trigger this deficiency include high soil pH (alkaline soils), over-liming, and poor soil aeration. Cool, wet spring conditions often aggravate the problem by limiting root activity and chemical availability of the micronutrient in the soil solution, making it difficult for the plant to uptake the necessary amount even in rich soils.

The economic impact of manganese deficiency can be substantial due to reduced biomass, lower grain quality, and diminished yields. Protective measures focus on foliar applications of chelated manganese fertilizers for immediate relief and long-term soil management, such as adjusting pH levels to make soil-bound manganese more available to the root system.

• Regular soil testing and plant tissue analysis.
• Adjusting soil pH to the optimal range.
• Foliar feeding with chelated manganese products.
• Improving soil drainage and physical condition.