When you go to the
auto parts store to buy a starter for your car, you buy the
prettiest one, right? When you buy a tractor for your farming
operation, you buy the prettiest one, right? When you buy seed to
plant in your fields, you buy the prettiest seed lot, right?
Wait a
minute…..that’s not right!
None of those
statements are right. “ Pretty” has little or nothing to do with
it. So why make seed prettier by film coating? Actually, film
coating is more than just making the seed look “pretty”. Let’s take
a look at what film coating does, and why you might film coat a
seed.
Film Coating
Compared to Other Seed Coats and Pellets
The
picture shows bare lettuce seed at the far left, next is film coated
seed (green), then encrusted seed (pink) and finally lettuce seed
with a full seed pellet around it (white). Film coating puts a very
thin, colored film around the seed, increasing the weight of the
seed by about 5%, without changing the shape of the seed. This is
in contrast with seed encrustment, which can increase seed weight
from 50% to 200, and a full pellet which can increase the weight of
a seed by as much as 3500%, (35:1) and completely change the shape
of the seed to a uniform sphere.
There are
companies that sell film coating materials that are especially made
for seed application. The actual film coat material resembles paint
that you would buy to paint your house, and is sprayed on the seed
and then dried. In it’s most simple form, the film coat material
consists of a polymer (large molecules in repeating chains), a
plasticizer (helps make the coat more elastic and/or less tacky
after drying), and a colorant.
So Why Apply a
Film Coat around the Seed?
There are three
basic reasons why it might be advantageous to film coat your seed.
The first reason being the most important.
1.
Fungicides and pesticides are completely enclosed around the seed by
the non-toxic film coating material. The pesticides stay directly
on the seed for maximum affect and workers handling the seed are not
exposed to any toxic chemicals.
2.
The
film coating material can help the seed flow better in the planter
box, depending on the type of film coating material used.
3.
The
color makes the seed easier to pick out of the soil when checking
for seed spacing during planting.
New Film Coat
Technologies
There are some
newer technologies that may make film coating seed even more
advantageous.
Precision
Laboratories, Inc. claims that their new film coating product
ProSurge can help increase yields.
Landec Ag, Inc. offers a film
coating polymer that prevents the seed from absorbing water until
the soil warms up. This would enable you to plant field corn in
cold wet soils, 3 to 4 weeks before normal planting time. The film
coat blocks water from entering the seed until the soil reaches
warmer temperatures. Once the preset temperature is reached, the
film coat chemically changes to allow water to pass through the film
coat, starting the germination process. INCOTEC
Inc. offers a film coat with a hidden marker to identify, and
trace seed lots after sale. When a specific laser is pointed toward
the seed, the marker shows up on individual seeds, identifying the
lot.
Next, we’ll
talk about the wild and woolly subject of biological seed treatments
in the article “Biologicals – Good Microbes vs. Bad Microbes”.
Keith
k.kubik@hmclause.com
