Technical Insight

Binders

These are basically the glue that holds the coating together, depending on the type of coating being produced. For thin film coating the binder will be the major film-forming component in the coating. For pellets the binder will be the adhesive holding the various powders together. Some binders can fulfil both of these roles, while other binders are either film or pelleting products, some will be especially good at only one of these.

Binders can also hold other ingredients within the coating, nutrients, pesticides and biological products. It is important to select the right type of binder so there is good compatibility with the other additives.

One of Centor Oceania’s strengths lies with the Seedworx Bio Friendly product range which works very effectively with biological products (Rhizobium).

Colours

It is very important to make sure that treated seed stands out clearly. Furthermore it is seen as a sign of quality if the treated seed shows a good finish in colour strength. Centor Oceania in its premium coating stable SeedWorks has a range of high quality colourants which demonstrate a superior coating even after many months.

Polymers

For ease of use, all-in-one products are simply a means of applying a binder, colour and finish to your seed. These are especially useful in keeping dust levels to a minimum during the treatment process, and also while planting. It is important to select the right type of product (polymer) for the crop and treatment process that is used.

Much effort is spent in selecting the right materials and determining the most effective ratios so that you can instantly benefit from seed coatings that really deliver in terms of coverage, effect and handling.

Blends & Powders

A powder will typically be something like a lime product that is used to produce basic seed pellets. Selecting the best powder is not always straight forward, and for more important products it is likely that a mixture of different powders will give a better outcome in terms of germination speed, or stress tolerance, these blends have been developed with these outcomes in mind.

Although we refer to our Finishing Powder Max, this is also a blend, as are our EasyPel and EasyOn pelleting products. The finishing powder is generally used as a barrier product, or simply in film coating were excessive liquid application is needed.

Nutrients and Growth Promoters

Incorporation of these ingredients in to a seed coating means that even before germination these beneficial actives will be right where they are needed.

Biologicals

There are many types of biological products, we know that our products work well with rhizobia and phosphate solubilising bacteria, and we continue to look at a wide range of biological products as this area continues to expand.

Fungicides and Insecticides

Still an important area of seed treatment, these actives being placed on the seed mean far less environmental impact than sprays applied over fields. It is important that these actives are applied well, with good even coverage and seed distribution and that once applied these products stay on the seed until planting.

The breakdown of the seed coatings of the product after planting is also an important consideration, so the actives are released to the growing plants.

How coating polymers work

Apart from the more obvious visual appearance, the seed coating polymer assists in keeping applied seed treatments in place, only releasing them when required.

Seed coating polymers work in the following way:

Stage 1:
The seed treatment (typically polymer, pigment and maybe active)is applied as a slurry with excess water (vehicle).

Stage 2:
The majority of water evaporates and a small amount moves into the seed.

Stage 3:
With water now removed, polymers form a layer, locking in pigments and actives.

Seed Coating Types

FILM COAT:

  • Thin layer
  • Seed shape & texture visible
  • Colouring for identification
  • Improved seed flowability

ENCRUSTMENT:

  • Build up layer – small (powders)
  • Seed shape – smoothed
  • Improved drilling & placement

PELLETING:

  • Build up layer – large (powders)
  • Seed shape – modified
  • Enables precision planting
  • Control of size & weight
  • Splitting or melting types

Film coating, encrustments and pelleting seed enhancements can all include fungicides, insecticides, nutrients and biologicals. In addition, we can build track and trace technology into our polymers for identification and security purposes.

 

Seed Coating – Polymer Formulation