Seed treatments come in a variety of formulations: dry flowables (DF), liquid flowables (LF), true liquids (TL), emulsifiable concentrates (EC), dusts (D), wettable powders (WP) and others. These materials may be used in slurry and mist type seed treaters upon mixing with water as specified in instructions on the product label. Special adhesives are incorporated into the dust formulations to adhere pesticide particles to the seed surface. Always apply seed treatment materials according to label instructions.
Commercial seed treatment is often desirable due to the specialized equipment required to properly apply treatments or to treat large volumes of seed. The primary concern of the commercial treater is equipment calibration to ensure delivering the proper amount of active ingredient on the seed. This has become especially important with more modern fungicides that require only very small amounts of material (less than 0.5 oz) per hundred weight of seed.
Detailed information on the process of treater equipment calibration can be obtained from the equipment manufacturer. Seed treatment manufacturer labels provide information related to mixing formulations and mixing procedures.
Information needed to properly calibrate a seed treater includes: 1) the correct labeled rate of the seed treatment material that will be used, 2) how many pounds of seed is dumped each time the weigh pan arm dumps and, 3) the size of the cup being used in the treater. This information will allow you to calculate the correct application rate for the seed and treatment material used.
A new generation of seed treater is becoming available that offers precision distribution of treatment chemicals on individual seed through atomization. These advanced controlled droplet application (CDA) machines offer complete seed coverage with lower water volume, shorter drying time, and continuous seed flow. These machines also reduce chemical exposure to employees and are capable of applying current and future products that may include both chemicals and biologicals.
Many seed treatment materials are available for on-farm use. These are known as hopper-box or planter-box treatments. Most hopper-box treatments are dry treatments formulated with talc or graphite which adheres the treatment chemical to the seed. Liquid hopper-box treatments are available as a fast-drying formulation. Good seed coverage is required for maximum benefit from any seed treatment formulations.
Obtaining thorough seed coverage can be difficult when attempting to treat seed in the field at planting time. Most seed treatment companies recommend that the planter box be filled only half full with seed, and half the required amount of treatment product added. Mix the product into the seed volume with a stick. Then add the remainder of seed to the planter box and add the rest of the required amount of product, again mixing thoroughly. Good results are also obtained by premixing seed with the product in a suitable container, then pouring treated seed into the planter box.
On-the-farm treaters are available that apply liquid or dry formulations to seed as it passes through an auger from the transport bin or truck to the planter boxes. These treaters are a very convenient way to apply seed treatment onto bulk seed. For additional information on on-the-farm treaters, contact a representative of the company selling planter-box treatments.