What is in this article?:
- White mold remains the No. 1 disease pest in Southeast peanut production.
- Since 1994, more tools have become available for the controlling the disease, including chemicals and new application methods.
- Producers need to guard against building resistance with certain fungicide classes.
WHITE MOLD REMAINS the No. 1 disease pest for Southeastern peanut producers, but more tools are available now than ever before to control it.
Different levels of risk
In 1994, growers were told to begin spraying peanuts approximately 30 days after planting, earlier if it was raining, to stay on a 14-day schedule, and to finish after seven to eight fungicide applications.
“Since that time, we’ve learned that there are different levels of disease risk in a field; those companies supporting Peanut Rx with prescription fungicide programs will say that you had better spray at least seven times if you’re at a high risk for white mold. But if you’re at low risk, we now say you can spray as few as four times as long as you stick with specific programs.”
Growers now have more fungicides than ever and better fungicides, he says. “But one thing that has not changed is that since the period from 1994 to 1996 – when Moncut, Folicur and Abound were introduced – we do not have a new class of chemistry. All of our new fungicides for white mold control fall within the triazole class, the strobilurin class or the SDHI class. We’ve got better chemistries and new chemistries, but we have the same classes. We need to protect what we have, because too much use of any one class may ultimately result in fungicide resistance and loss of efficacy to the disease. We’ve already seen resistance develop to Folicur or tebuconazole on leaf spot disease.”
One of the most important things that’ll happen to peanut growers in 2014 is that azoxystrobin sold as Abound will go off-patent.
“And I don’t know if that’s a good thing,” says Kemerait, “because azoxystrobin is extremely sensitive to resistance development. It’s one of our most important classes not only in peanuts but in other crops as well. If we develop resistance to azoxystrobin in our peanut fields, other fungicides will take a hit. Since 1994, we’ve had the strobilurin chemistry brought to peanut farms. If we misuse it in 2014 and beyond, other chemistries will be affected.”