The role of zinc in plant development: signs of deficiency and excess
A zinc atom may be small, but zinc plays an essential role in plant growth and development. Plants need this micronutrient for vital functions at different stages of their life cycle. Zinc is a key component of many plant enzymes and proteins and is one of the 8 essential micronutrients. A lack of zinc in the soil, or limited availability, reduces crop production, yield and the nutrient content of cereals. Excessive zinc application, however, can stunt plant growth and reduce yield.
♻️ Why do plants need zinc?
▪️ Enzyme activation: Zinc helps activate enzymes involved in processes such as photosynthesis, protein synthesis and hormone regulation.
▪️ Cell division: It supports cell division and growth, which are essential for plant development.
▪️ Protein synthesis: Zinc is essential for synthesising proteins, the building blocks of the plant.
♻️ Signs of deficiency: When plants receive insufficient zinc, they show symptoms such as:
▪️ Stunted growth: Plant growth slows and no longer progresses at its normal rate. ▪️ Yellowing leaves: Leaves may turn yellow between the veins, a condition known as chlorosis. ▪️ Reduced yield: Plants produce fewer fruits, or fruit that is less well developed. ▪️ Poor root development: Zinc deficiency can restrict root growth.
♻️ Sources of zinc for plants:
▪️ Soil: Plants take up zinc from the soil through their roots. ▪️ Organic matter: Materials such as compost and manure enrich the soil with zinc. ▪️ Fertilisers: Zinc-containing fertilisers help correct soil deficiencies. ▪️ Zinc-containing foliar nutrients: Foliar zinc sprays help plants absorb this element more effectively.
♻️ Excessive zinc application can cause:
▪️ Root damage: Excess zinc can damage the root system, affecting its ability to absorb water and nutrients. ▪️ Reduced iron uptake: Excess zinc may interfere with the uptake of other essential nutrients, such as iron, causing deficiencies. ▪️ Stunted growth: High zinc levels can slow plant growth and development. ▪️ Leaf discolouration: Leaves may turn yellow or develop brown spots. ▪️ Impaired photosynthesis: Excess zinc can disrupt photosynthesis, hindering plant and fruit development.
Although plants need only small amounts of zinc, its role in growth and development is crucial. From enzyme activation to cell growth, zinc is important throughout the plant’s life cycle. Understanding its importance and supplying it correctly can significantly improve plant and fruit characteristics.
As noted above, zinc can be supplied in several ways, through either foliar or root application. The key is to consider the form of zinc in the product and the product’s origin. Chelated zinc (EDTA) is one of the most common and effective forms because plants absorb it quickly and easily, allowing zinc deficiency to be corrected promptly. The Spanish company Nufol offers Zintec, a product containing EDTA-chelated zinc. Its chelated formulation ensures rapid and effective correction of zinc deficiency. It can be used in all types of crops through foliar spraying or fertigation. Zintec is an organic product suitable for organic farming and leaves no residues on the plant.
Another effective zinc-containing product is Fertium ZnMn from Fertinagro. This liquid fertiliser contains amino acids, zinc and manganese. The zinc and manganese cations are complexed with amino acids to form zinc-manganese aminoates, which also support calcium mobility and improve its effectiveness. The free amino acids provide a biostimulant effect, while the product also helps prevent and correct zinc and manganese deficiencies. Fertium ZnMn can be used in all types of crops.
Compound fertilisers also supply zinc together with other important macronutrients and micronutrients. One example is Macfert from Nufol, which contains zinc alongside nitrogen in organic, nitrate and amide forms, potassium, boron, magnesium, iron and organic carbon. It also contains fulvic acids.