Zinc is one of the key micronutrients for plants and has a fundamental function in their physiology. A correct supply of zinc to plants allows healthy development, proper functioning and resistance to environmental stresses.
See what you can find out in the text:
- the role of zinc in the plant
- zinc and resistance to stress factors
- symptoms of deficiency
- plants sensitive to deficiency
- which fertiliser to use?
The role of zinc in plants
Zinc is involved in many biochemical and physiological processes. It is a component of many enzymes, including RNA polymerase, which is essential for RNA synthesis in plant cells. In addition, zinc activates enzymes responsible for sugar metabolism, gene expression (e.g. via so-called zinc fingers) and protein synthesis. Through these functions influences the normal growth and development of plants.
One of the most important processes indirectly influenced by zinc is the synthesis of auxins, the plant hormones responsible for growth. Zinc is involved in the production of tryptophan (an amino acid), which is a precursor of auxins (growth hormones), making it crucial for root and shoot development.
Because of the above functions, zinc deficiency can have serious consequences.
Zinc helps the plants to resist stress factors
The role of zinc in increasing plant resistance to stress factors should not be overlooked either. These factors are both biotic (e.g. pathogen infection) and abiotic (e.g. frosts). Plants properly supplied with zinc are more resistant to unfavourable environmental conditions, so it is even worth using zinc fertilisers prophylactically, especially before frosts are forecast.
Transportation in plants
Zinc is a micronutrient with low mobility in the plant. In a deficiency situation, the element does not move from older to younger organs. This means that the first symptoms of deficiency are visible on young leaves and shoots. In the case of a long-term zinc deficiency, the whole plant is affected, which can lead to a significant reduction in yield.
Zinc is an antagonistic nutrient to phosphorus, which means that its availability to the plant may be limited when soil phosphorus levels are high. This is an important aspect to consider in fertilisation practices.
Zinc deficiency – symptoms
Changes in leaf colour:
- fading of older leaves
- mottled chlorosis of younger leaves
- reddening of veins and leaf margins in dicotyledonous plants
Disease-related changes:
- streaky chlorosis on maize leaves
- spotty necroses on cereal leaves, which can be confused with fungal infections
Plant growth disorders
- shortening of internodes, especially in perennial plants
- diminutive, brittle and stiff leaves
Zinc deficiency – oilseed rape
Zinc deficiency is rarely apparent in oilseed rape cultivations. Deficiencies mainly occur on alkaline soils and on soils over-fertilised with phosphorus, which is a strong antagonist of zinc. The greatest seed yield losses are generated by deficiencies during flowering.
Zinc deficiency – apple tree
When zinc deficiency occurs in an apple crop, the shoots are thin, poorly leafed, with shortened internodes, with a rosette of leaves at the top (known as apple profileration). The leaves in the rosettes grow close together, are small, narrow and have a smaller surface area. In apple trees, the formation of clusters of small leaves occurs especially during the early growing season. Chlorotic spots may form between the main nerves of the leaves and on their margins due to zinc deficiency. With severe and prolonged zinc deficiency, the shoot tips die off.
Plants particularly sensitive to zinc deficiency
Some crops show particular sensitivity to zinc deficiencies, requiring increased attention from farmers. Such plants include cereals and maize.
In maize cultivation, zinc is a micronutrient of great yield-forming importance. It is important that maize plants are properly nourished with zinc from the very beginning of growth. Maize requires foliar feeding with zinc, regardless of its availability in the soil. Symptoms of zinc deficiency in maize include: bleaching of seedlings, stunted growth and dwarfing of plants. A characteristic symptom is chlorosis in the form of white or yellow-white stripes on both sides of the main leaf nerve.
In other cereal crops, zinc deficiency manifests itself as shortened stem tip and narrow leaves. Brown and necrotic patches appear on the leaves of zinc-deficient cereals, gradually extending towards the base and apex of the leaf.
Which fertiliser will work best?
To avoid problems related to zinc deficiency, it is worth using appropriate fertilisers. A perfect example is AMINO ULTRA Zn-24 – a foliar zinc fertiliser with GCAA technology from INTERMAG.
AMINO ULTRA® Zn-24 is an inorganic fertiliser in the form of an ultragranulate with patented GCAA technology, in which micronutrients are combined with the amino acid glycine. Glycine is the smallest and most mobile amino acid in plants, making the delivery of zinc to plants in AMINO ULTRA Zn-24 zinc fertiliser fast and precise.
AMINO ULTRA® Zn-24 fertiliser is designed for foliar feeding of all plant species, and dissolves perfectly and quickly in water. Regular application of zinc fertilisers, especially in sensitive crops such as maize and cereals, increases yield and improves the quality of production.
