In 2020 Wilchem released a range of wettable micro granule EDTA’s.
At Wilchem we are always looking to improve the range of nutritional products available to meet the changing needs in the market, not only new products but improved versions.
Wilchem’s new range of EDTA’s are Sodium Free, utilising potassium through a new formulation that will provide a significant plant benefit. The Potassium in the new range is plant available, giving not only a plant benefit but also a commercial advantage.
A comparison of product analysis can be seen below.
IUPAC (International Union of Pure and Applied Chemistry)
“Chelation is the formation of bonds between two or more binding sites within the same molecule and a single central metal atom.”
The EDTA molecule (ethylenediaminetetraacetic acid) is the strongest chelation agent currently available. The benefit of strong chelate bonds is that it makes this range of products the most compatible micronutrient products for tank mixing and for soil applications. This is very important for furrow injection in alkaline soils and tank mixes that contain soluble phosphates.
The synthetic EDTA molecule does not provide any additional nutritional benefit, it purely acts as a stable transporter of the micronutrients in solution.
Foliar micronutrient applications can enter the plant two ways. Via the stoma which is used by the plant for respiration or by direct absorption through the leaf cuticle. The leaf cuticle is highly negatively charged making it difficult for positively charged ions to be absorbed. Chelating the positive ions to a highly negatively charged EDTA molecule creates a molecule that remains negatively charged that can pass through with no interaction. The nanopores that allow passage through the cuticle are very small. EDTA chelates have a low molecular weight and can pass through these pores.
EDTA chelates cannot be absorbed directly through the cell membrane. The micronutrient must first be uncoupled from the EDTA molecule either in the rhizosphere (soil applications) or epidermis or palisade cells (foliar applications). It can then be absorbed through the cell exchange process as pictured to the right.
Wilchem’s Sentinel Range of EDTA chelates is the most compatible of our offering of liquid micronutrient product lines. Key areas where there is benefit in using this product line over amino acid chelates or liquid sulfates are in tank mixes with one of the following products or applications –
The Sentinel Range should not be used in tank mixes in the presence of free calcium or potassium.
The liquid solutions manufactured by Wilchem can be combined in tank mixes with a range of commonly used plant protection products. It should not be assumed that every product is compatible with every other fertiliser or chemical. If there is any doubt about the proposed mixture then a simple jar test should be done as a precaution.
The above description is a guide to the physical compatibility of the Wilchem Sentinel micronutrient solutions. We cannot guarantee the chemical compatibility of two or more products when mixed together. Many herbicides, insecticides and fungicides are produced by more than one manufacturer. The concentration of active ingredients, solvents and emulsifiers and other adjuvants may vary between manufacturers. There may also be changes from year to year by the same manufacturer. It is important that jar testing be done first to ensure compatibility.
Use the following steps to do a jar test.
1. Pour the correct ratio of water to be used per hectare into a clean glass graduated jar.
2. Add each intended fertiliser or chemical to the water. Always start by adding the least soluble products first (such as the powders, granules and suspensions) and the ending with the clear aqueous solutions.
3. If there is any immediate visual reaction, do not proceed with the mixture. These reactions may result in some precipitation, a curdling of the mixture or even resulting in mixture heating and bubbling. If no visual reactions occur then the mixture is generally regarded as physically compatible.
4. The appearance of physical compatibility is not a guarantee that the mixture is chemically compatible and safe to apply to foliage.
Always ensure that the micronutrient solution is added last to the tank mix and agitation is continued.
It is recommended that a small trial area be sprayed and observed for 24 hours before spraying a larger area.
Disclaimer: All technical data and recommendations, whilst based on our research and believed to be reliable, are given in good faith but without warranty. It is understood that users will independently determine the suitability of content for their individual requirements.
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