Temik is the “Cadillac” treatment when it comes to preventing thrips damage in cotton. However Temik may be in short supply this year. A group of “concerned” citizens have gotten a judge to temporarily force the closure of the plant in West Virginia where the precursor ingredient of Temik is manufactured. As of now we do not expect the plant to reopen until at least March 28, 2011.
For thrips control, no more than 3.5 pounds per acre of Temik should be required to control western flower thrips. Little of the data we have collected over the years shows a benefit from using 5 pounds per acre of Temik instead of the 3.5 pound rate, although the higher rate may provide 3 to 5 day of additional control.
Temik at 3.5 pounds per acre will generally provide 24 to 30 days of thrips control post- emergence. The length of control with Temik depends on soil moisture and precipitation. In Sunray, Texas, in 2010, we experienced very high rainfall and Temik appeared to leach out of the root zone and provided only about 12 days of control post-emergence. Even Temik may require follow-up foliar sprays on occasion.
Seed treatments for thrips
With the possibility of Temik being in short supply, there is increased interest in seed treatments this year. The good thing about seed treatments is that they are easy to use, require no special equipment, and are fairly safe to handle.
Seed treatment options for thrips control include Gaucho Grande, Cruiser, Avicta Complete Cotton, Avicta Duo Cotton, and Aeris. The length of thrips control will vary by product, soil moisture, precipitation, and thrips pressure. Additionally, your choice of a seed treatment should consider nematode and disease potential as well.
Depending on which seed company you are obtaining seed from, you will have different options on seed treatment. Some seed companies have limited options in some categories or require you to purchase one component to get another. For example to get a premium fungicide you may be required to pay for an insecticide. If you cannot obtain the treatment you want from the seed company you may need to get the treatment applied “downstream” from a company or dealer that applies seed treatments.
Let’s look at what the various seed treatments bring to the table in regard to thrips control.
Gaucho Grande (imidacloprid) is a widely used thrips control product in many parts of the cotton belt, but tends to be weak against western flower thrips, which is the predominant thrips in the Texas High Plains. For us, Gaucho Grande will usually provide about 7 days post-emergence thrips control. However, if you end up with primarily onion thrips instead of western flower thrips as was the case in many areas last year, you can expect Gaucho Grande to perform equally to the other seed treatments.
But because you don’t know which species of thrips will show up, you need to plan for the worst, western flower thrips. For his species, the better thrips control seed treatments include Cruiser, the Avicta products and Aeris. Cruiser contains the single active ingredient thiamethoxam, and is in the same insecticide class as imidacloprid. However, Cruiser is more active towards western flower thrips than Gaucho Grande and will provide 14 to 18 days post emergence thrips control.
Aeris is a combination of imidacloprid and thiodicarb. Imidacloprid is the same active ingredient as Gaucho Grande, but the inclusion of thiodicard significantly increases the length of control of Aeris over Gaucho Grande to 14 to 18 days post emergence control. Thiodicarb also has some nematode activity (see nematode section for details). Prior to 2009, Aeris seed treatments automatically included the inclusion of the premium fungicide Trilex Advanced, but now Aeris can be applied separately.
Avicta seed treatments are available in two options, Avicta Complete Cotton and Avicta Duo Cotton. As far as thrips are concerned, these products are identical and are the same as Cruiser. They have the same active ingredient as Cruiser for thrips (thiamethoxam), and like Cruiser, will provide 18 to 21 days of post emergence thrips control.
The differences among Cruiser, Avicta Complete Cotton and Avicta Duo Cotton are the other active ingredients. Both of the Avicta products, in addition to thiamethoxam, include abamectin for nematode management (see nematode section for details), and Avicta Complete Cotton also includes the premium fungicide treatment Dynasty CST (see disease section for details).
Regardless of the seed treatment utilized, keep in mind that effective control will usually not last more than 21 days under constant thrips pressure, and follow-up foliar sprays may be necessary to protect the crop once these treatments wear off.