4-6 leaves stage of corn development (usually beginning-mid May) is one of the most important in terms of further yield formation.
Out of all indispensable elements of corn mineral nutrition zinc is the most critical one. The role of this element for corn plant is multifunctional. Even its temporary shortage cannot be replaced by other elements.
What is the uniqueness of zinc for corn at this stage? In our opinion, we need to take into account three main functions that this element performs in the plant.
The first one is participation in the synthesis of auxins, which provide active growth of the vegetative mass. In field trials, after zinc application the first leaf node was placed higher as well as the plant in general was higher than without zinc.
The second function is more active use of seed nutrient reserves by the plant which is illustrated by photo 1:
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Photo 1: On the left – check (untreated), on the right – 1 l/ha of Ecoline Zinc (Chelate) was applied. (Demo field of Pioneer Nasinnya Ukraina, Ternopil region, 2018)
The seed contains a significant amount of reserve nutrients, to accelerate the release of which zinc is required as it activates a specific group of enzymes.
The third function of zinc is its impact on the ear formation.
Despite the fact that zinc content in the soil can seem sufficient for the development of the crop (for example, based on soil test), many factors reduce its actual availability for plants during their critical stages of development. These factors are: low soil moisture, too low or too high temperatures, carbonates, insufficient development of the root system etc.
This particular spring, growth of corn plants was stalled after germination due to low temperatures. Under such conditions, in many regions of Ukraine we forecast symptoms of zinc deficiency and stress which can negatively affect the yield. Besides, signs of deficiency of other elements of mineral nutrition - particularly nitrogen, potassium, zinc and phosphorus - are expected at certain fields.
To eliminate crop stress and shortage of certain elements, to ensure growth activation of corn we recommend foliar application of Ecoorganic fertilizers at this stage of crop development.
Depending on the situation on each specific field we recommend to use the following products:
- Ecoline Zinc (Chelate) - 0.5 - 1.0 l/ha – in case of zinc deficiency, as a minimally indispensable element of the technology;
- Ecoline Phosphite (K-Zn) - 1.5 - 2.0 l/ha – in case of zinc and phosphorus deficiency;
- Ecoline Phosphite (K) - 1.5 - 2.0 l/ha - to eliminate deficit of phosphorus, potassium, and to provide for better growth of the root system;
- Ecoline Phosphite (K-Amino) - 1.5 - 2.0 l/ha - a special composition to overcome plants stress and to enhance root system growth;
- Ecoline Universal Growth (Amino) - 1.0 - 2.0 l/ha - special anti-stress fertilizer with high content of amino acids and balanced composition of macro- and microelements - to eliminate plants stress and to enhance growth processes;
- Gros Root Growth - 1.0 - 1.5 l/ha - special fertilizer with phosphorus in the form of phosphite, with amino acids and phytohormones - is recommended in case of plants’ growth lagging.