Zinc as a micronutrient in plant nutrition

Zinc (Zn) is an essential micronutrient for plant growth and development. Although it is required in very small amounts, its deficiency can cause significant physiological disorders that affect crop yield. Its availability in the soil and its absorption by the plant depend on various factors, so it is essential to understand its role and the strategies to prevent or correct its deficiency. In addition, identifying the symptoms and understanding the causes of its deficiency allows effective decisions to be made to correct and prevent it.

Zinc plays a fundamental role in several physiological and biochemical processes within the plant, being essential for various metabolic pathways. Its contribution is key in multiple functions that ensure adequate growth, development, and response to stress. Its main functions include:

• Growth regulation: It is essential in the production of auxins, hormones that are essential for root development and cell elongation.
• Carbohydrate metabolism: It contributes to the transformation of sugars, which improves photosynthetic efficiency.
• Cell membrane formation: It contributes to the structural stability of membranes and the integrity of cell walls.
• Antioxidant protection: It is involved in defense mechanisms against oxidative stress caused by adverse environmental factors.

Symptoms of zinc deficiency in crops

Zinc deficiency mainly appears in actively growing tissues, as its mobility in the plant is limited. Symptoms may vary depending on the severity of the deficiency and the type of crop compromised. The most representative signs include:

• Interveinal chlorosis in young leaves: Appearance of yellow stripes between the veins, while the veins remain green.
• Necrosis at the leaf edges: In severe cases, the leaves may show necrosis and deformities.
• Dwarfism and internode shortening: Limited growth with small, deformed leaves.
• Deformed and clustered leaves: “Rosette” appearance due to shoot shortening.
• Reduction in fruit production and quality: Negative impact on fruit or grain setting and filling.

Factors limiting zinc availability

Zinc absorption by plants can be influenced by several soil and climate factors that affect its availability in the soil.

One of the main factors is high pH: in alkaline soils, especially when pH exceeds 7.5, zinc tends to precipitate, significantly reducing its availability to the plant. Soil texture and organic matter content also play an important role. In sandy soils, for example, zinc tends to leach easily, while in soils with high organic matter content it can become immobilized, limiting its absorption.

Another relevant factor is the excessive presence of phosphorus. When high doses of phosphate fertilizers are applied, ionic competition can occur, reducing zinc absorption by the roots. Likewise, in calcareous soils or soils with high clay content, zinc tends to become fixed in unavailable forms, making it difficult for crops to use it.

Finally, water stress conditions, whether due to drought or excess water, affect the mobility of zinc in the soil profile, compromising its uptake by the root system.

Strategies to correct zinc deficiency

To avoid deficiencies and optimize plant nutrition, it is recommended to adopt effective agronomic strategies.

The use of fertilizers enriched with chelated zinc (EDTA, EDDHA, etc.) or complexed zinc (LS, amino acids, etc.) improves availability in high pH soils and its assimilation in foliar applications.

To this end, Herogra Especiales offers both complexed and chelated zinc-based products to improve the uptake and translocation of this micronutrient in the plant, thereby preventing and correcting deficiencies in the crop.

The main products of Herogra Especiales catalog are:

– Heromicro Zinc Complex: Liquid fertilizer based on zinc complexed with amino acids for the prevention and correction of deficiencies of this micronutrient. Being complexed with amino acids allows assimilation and translocation, making the treatment more effective.

– Herocomplex Zn-Mn ECO: Liquid corrector based on manganese and zinc complexed with lignosulfonates (LS), which guarantees high stability and availability of micronutrients for the plant. Its composition is enriched with amino acids, which promote better nutrient uptake, increase crop tolerance to abiotic stress situations, and act as biostimulants, boosting plant development. Besides, Herocomplex Zn-Mn ECO is certified for organic agriculture use.

All of the above confirms that zinc is a key micronutrient for plant growth and crop yield. Its deficiency can cause significant alterations in plant physiology, affecting vital processes such as cell division, protein synthesis, and the formation of reproductive structures. Therefore, it is essential to implement appropriate management strategies to ensure its proper availability. Choosing the zinc source and the application method should be based on soil characteristics, crop type, and the products available on the market. Furthermore, constant nutritional monitoring and the use of innovative solutions will optimize plant nutrition efficiency, improving the profitability and sustainability of production systems.