Seed treatment basics for improving planting material

Successful seed germination and optimal utilization of all needed resources during the early stages of crop development are essential for profitable agricultural production. In the very first steps of a crop’s lifecycle, any kind of unfavorable biotic and abiotic events will result in poor crop development or in the worst-case scenario total crop loss. Seeds must overcome many obstacles, including diseases, pests, and environmental pressures. Applying a seed treatment for additional protection against such events is one of the possible strategies that many modern farmers take to ensure that their crop receives the early protection it needs. The term “seed treatment” describes the use of biological, physical, and chemical agents and processes to protect seeds in various environments such as soils and storage facilities. From this, we can say that seed treatment is mainly used in two agricultural activities: prior sowing and storing.

These agents are directly applied onto or into the seeds and very often, the seeds are treated in a combination of several agents which later help to control the damage that can be done by pests, diseases, and unfavorable conditions.

Here is a list of potential seed treatment agents that are often used in agricultural production systems:

• Fungicides
• Insecticides
• Bird repellents
• Seed enhancements
• Additives

The agent or the combination of agents that could be potentially used in the seed treating methods depends on the needs of the farmers, or more precisely, on the actual situation in the agricultural fields and the presence of pests, pathogens, or specific abiotic conditions.

There are synthetic and organic seed treatments, depending on the source of the treatment component.

Why seed treatment is necessary?

For achieving the desired yield and maximal utilization of the seed’s genetic potential every farmer must use seed protection methods such as seed treatment. Seed treatment is not a new method for ensuring proper agricultural production of healthy plants. Farmers have been looking for strategies to safeguard their crops throughout history such as the oldest evidence of seed treatment, dating around 60 A.D. when wine and crushed cypress leaves were used to preserve seed from storage insects.

Usually, treated seeds are sown directly in the soil, where lots of pathogen fungi, bacteria, nematodes, etc. can potentially hinder the germination and sprouting or even damage the seed before germination. Without seed treatment, a very small percent of the sown seeds can succeed in their early stages of growth development, directly jeopardizing agricultural production.

Moreover, after the sowing operation, there is plentiful food ready for the birds to pick. Many bird species feed on seeds that make the agricultural fields an ideal feeding ground. For minimizing the risk of birds feeding on the freshly sown agricultural fields, seed treatment with bird repellent is the easiest and most effective way to ensure proper sprouting of the seeds without any missing lanes of seeds in the fields.
Another situation when seed treatment is necessary is when the seeds have small dimensions making them difficult to manipulate by the seeding machines.

Are seed treatments dangerous?

Very often treated seeds contain insecticides, pesticides, and other harmful substances in their coating. Depending on the agents that were used in coating the seeds, the seeds can be hazardous for the people that are handling them, the wildlife that can potentially consume them, or the water bodies that are nearby the agricultural fields.

When planting treated seed, consider the following precautions:

• Exposure could occur to those who handle or use treated seed. As with other insecticides, handle treated seed with caution.
• Carefully dispose of treated seed. Animals might consume it if it is spilled or poorly disposed of.
• Never compost or burn treated seed.
• Never ingest treated seeds or use them as feed for animals.
• Avoid children, who can be drawn to the vibrant colors. You may not use treated seed for projects or show & tell in the classroom.
• To stop wildlife from eating spilled seed, tidy it up or cover it with soil.
  
  

What are the types of seed treatment?

There are several existing seed treatment methods:

Fungicidal and insecticidal dressing

This method of seed treatment helps the growers to control different types of fungal diseases such as root rots, blights, molds, smuts, etc., as well as, repel or kill various soil pests that can damage the seeds or the crops in their earliest stage of development.

Usually, this type of seed treatment has three main purposes: disinfection, disinfestation, and protection of the seeds.

Here is a list of the most common active ingredients in fungicidal and insecticidal seed treatment:

Fungicides: Fludioxonil, Tebuconazole, Metalaxyl, Thiabendazole, Azoxystrobin, Pyraclostrobin,Ipconazole.
Insecticides: Imidacloprid, Clothianidin, Thiamethoxam.

Strengthening and protection treatment

This process is generally done by soaking the seeds in specific solutions or mediums in order to ensure proper seed germination rate and/or strengthen the seeds to endure lower temperatures, draughts, or wet soil conditions. One of the most used agents for such treatments are different kinds of fertilizers (organic/mineral).

Granulation

Granulation is a process where small dimension seeds are coated with extra material in order to enlarge their diameter to make them easier for manipulation. This process is extremely important when the farmers are implementing precision agriculture technology and equipment. For enlarging the diameter of the seeds, clay powder is often used.





Managing seed activity

With the help of organic solvents, infusion of liquids and their penetration in the seeds is possible in order to break the dormancy of the seeds. On the other side, with the help of salt solutions and their capability to alter the osmotic pressure in the cell, seeds water absorption can be slowed down. This is particularly helpful in situations where we have seeds with larger embryos and higher protein content to synchronize their germination in soils with lower temperatures.

Which is the best seed treatment?

A perfect example of the best seed treatment does not exist, because every seed treatment has its own ability to prevent, cure or mitigate a specific or a combination of specific unfavorable conditions and events that can occur during sowing or storing the seeds.

Seed Treatment Benefits

Seed treatment is particularly beneficial in the following situations:

• For early sowing when excessive soil moisture and low soil temperature increase the risks of damping-off diseases;
• In conservation tillage practices;
• In the implementation of integrated pest management processes;
• In the process of soil-improving practices via providing beneficial bacteria;
• In plant protection processes, making the seeds free from pathogens (bacteria, fungi, nematodes, pests);
• Reducing costs for plant protection due to decreased occurrence of plant disease and damages;
• Boosting crop performance and enhancement of crop growth with the help of providing sufficient nutrients through the coating seed treatment process;
• When germination capacity is low.

According to Bayer Crop Science, between 20 and 40% of production is lost each year as a result of diseases, insects, and weeds. In the end, growers want to give their seeds the best chance to develop into a strong crop ready for harvest. One of the instruments in their toolkit to assist them in doing this is seed treatments.

One of the most expensive items a farmer must buy, aside from farm equipment, is seeds. Additionally, they have to buy it every year. Farmers and the businesses that assist them are always looking for more ethical and inexpensive ways to preserve the value of the seed. Farmers can maintain the value of their seeds by using seed treatments.