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.
Changes since 1994
So what has changed in terms of white mold control since 1994, and what should growers consider going into the 2014 growing season?
The basic foundation hasn’t really changed since 1994, says Kemerait, and it includes practices such as rotating, planting more resistant varieties, and using the appropriate fungicide program.
“But one thing that has changed is Peanut Rx. It started out as the tomato spotted wilt virus risk index and now includes white mold. It allows you to take all of the components like rotation, new varieties, seed spacing and planting dates and see how they affect white mold. I’d recommend that you look at this and see what factors you can improve upon to reduce your risk not only to white mold, but to leaf spot and tomato spotted wilt as well.”
Another change has been breeding for resistance, he adds. “It once was just a dream, but we’ve gotten more and more resistance to tomato spotted wilt virus, and we’re getting more resistance to leaf spot diseases.
“The good news is that our breeders continue to bring better varieties to the table. One of those is Georgia-12Y. It is better than Georgia-07W for having white mold resistance, and it has higher yield potential. So when you’re using the risk index or Peanut Rx, you can look at the varieties that are available and see how their resistance compares to favorites like Georgia Green or Georgia-06G. The combination of improved varieties coupled with the use of Peanut Rx allows you to come up with a system of improved white mold control.”
Tebuconazole is on the market, and it’s available at a bargain price, says Kemerait.
“That’s a problem for me, but in some ways it’s a good problem. There’s not a grower in Georgia who doesn’t need to treat for white mold, and using tebuconazole may be a good option. It may be the best option in some non-irrigated fields.
“The problem is that we’re overusing it. Some growers will ask, “Why use 7.2 ounces (the labled rate) when you can put out 14 or 21 ounces? Why spray four times when you can spray seven times cheaper than you could spray Bravo 10 years ago?” We’re overusing a class of chemistry.”
But as a grower, you might make more money by spending more money, he says. “There may be fungicides out there that are better for white mold in a tough situation. They are better, and you’re missing an opportunity if you simply do what you’ve always done. If you stick with only what you’ve done since 1994, than that’s what you’ll always get.”
Other white mold fungicides likely to be available to peanut producers for the first time in 2014 include Priaxor from BASF and Custodia from Farmoz or Mana – a combination of azoxystrobin and tebuconazole.