Controlling rice diseases for Missouri Bootheel farmers begins with variety selection and ends with the potential use of a foliar fungicide.
But there are a lot of things to do in-between, too.
Cultural practices to minimize losses to disease include crop rotation, resistant varieties, planting into warm soil and the use of fungicides when necessary, according to Allen Wrather, plant pathologist at the University of Missouri Delta Center in Portageville, Mo.
Wrather also suggests that growers plant for a stand of 15 to 20 plants per foot.
“That's not a thin stand, but it results in an open canopy, which will dry more readily in the morning. Apply only the amount of nitrogen for that variety.”
In addition, if your scout sees disease problems, he needs to assess the weather for the next five to 10 days. If the weather looks like it's going to be suitable for diseases, then treat.
Sheath blight is the most prevalent rice disease in the Missouri Bootheel, according to Wrather. “Blast is deadly when it occurs, but it is rare in Missouri.”
Wrather says foliar fungicides Quadris and Gem “are excellent for rice disease control. Our data indicates that Gem and Quadris reduced disease damage greater than other products tested.
“Coverage is critical,” Wrather stressed. “It's difficult to get these products down into the plant canopy where the disease is developing. So it's critical that the aerial applicator use as much water as possible, at least 5 gallons per acre. And they need to be close to the canopy when they're going across the field.”
For more information on soybean and rice diseases, visit http://aes.missouri.edu/delta/.