Insecticide Seed Treatment In Wheat ... Know What You’re Buying!
DR. SCOTT STEWART
JACKSON, TENN.
Insecticide seed treatments are not universally recommended in wheat, but they are often suggested for early planted wheat. Indeed, recent data suggests that a foliar insecticide application late in the fall or during the winter can often accomplish the same objective, sometime even better, of preventing early transmission of barley yellow dwarf virus (BYDV) by aphids.
Insecticide seed treatments at least partially accomplish the same thing and may also add some protection against Hessian fly if using the highest labeled rates. Also, seed treatments do offer the advantage in that they don’t require any grower action except planting.
However, not all seed treatments options are alike, and you need to carefully check what rate of insecticide is being put on the seed. In Tennessee, a standard insecticide seed treatment rate for Cruiser 5F, NipsIt 5F and Gaucho 600 would be about 1 oz of product per 100 pounds of seed. The labels suggest going no lower than 0.75 – 0.8 oz, depending on the product, for aphid control. Now keep in mind that at 1 oz/100 lbs seed, you get 0.039 lbs of active ingredient for the above products (they all contain 5 lbs ai/gal).
This seems pretty clear until you start looking at all the different insecticide/fungicide packages that are being marketed. Some of these options are tailored for the Midwest where aphids and BYDV are rare problems. Two examples are below.
• CruiserMaxx Vibrance Cereals: The label suggests rate of 5 to 10 oz/100 lbs of seed, but at even the mid-rate of 7.5 oz, you are getting 0.015 lbs of active ingredient (about 40 percent of the typically recommended rate). This is because the formulation of this product contains only 0.256 lbs ai/gal. And note there is a big difference between 5 and 10 oz rate, and just saying “CruiserMaxx Vibrance for Cereals” doesn’t indicate what rate was applied.
• NipsIt SUITE Cereals of Seed Protectant: This product also contains 0.256 lbs ai/gallon of insecticide (clothianidin). The label indicates at rate range of 5 to 7.5 oz/100 lbs of seed, so even at the maximum, you are talking about 40 percent of the rate recommended for aphid control.
Neither one of these products lists anything other than control of wireworms on their labels. These low rates have not been tested for aphid control in Tennessee, and the label would suggest they do not work (or at least not for very long). So what happens when you ask for your seed to be treated with an insecticide seed treatment? If you don’t know you better ask! ∆
DR. SCOTT STEWART: IPM Extension Specialist, University of Tennessee