Disease management should be part of crop budget

Active disease management is an on and off issue for growers. With the current heat wave and severe drought in the south central U.S., wheat diseases have not been a big issue in 2011. But the dry environment does not mean producers get a pass on next year’s disease management plan. Brad Ruden, senior technical service representative for Bayer CropScience, said wheat producers should be sure to include a plan for disease management as they develop a budget for the year.

“You get one shot to get plants out of the ground and growing,” Ruden said. “Even the most popular wheat varieties with the most disease tolerance and highest yield potential still respond to fungicide applications in the presence of diseases.”

During his presentation to the Profit Maximizer crowd, Ruden said a fungicide will move upward and outward when applied to a plant, not down the stem. Therefore coverage becomes a critical issue for growers. He said to keep in mind the compound can also be a relatively low-cost solution to issues that can otherwise reduce the plant’s ability to respond.

“The most expensive inputs growers will have are land rent, fertilizer and seed,” he said. “If we can optimize a less expensive product like seed treatment it can optimize plant health early on in the season and make sure we are getting adequate return on all of our other investments that might end up costing more per acre.”

The focus on growing a healthy crop is different than other pest management tools, he said. When looking at weed management, for example, producers can scout the field post emerge to find weeds and if they find a problem, it can be treated. A crystal ball, however, is needed to predict if and when diseases might be present. Effective management should be based on susceptibility of the wheat variety, on timing and the environment. This means disease management must be done before diseases actually appear in the field.

Diseases also vary greatly according to geography, Ruden said. Fusarium head blight or scab can hit no matter where the wheat field is located, while a few soilborne viruses are more prevalent in the southern and central plains.

“I tell growers that every disease management plan will be unique to their soil and environment,” he said. “Nothing in agronomics works in every environment, which we’ve heard from another speaker during this conference.”

One suggestion Ruden offers to control FHB or scab is to tip or angle spray nozzles forward to better penetrate the wheat head with fungicides. This, he said, optimizes the ability of the product to control the disease organism, rather than just using a standard, straight head-down nozzle positioned on a new sprayer.

In addition to being a complex surface, a wheat head is a vertical target, which means it is difficult to achieve optimal FHB management. At best, Ruden said, a producer could have 75 percent disease control, not the 90 to 95 percent rate accomplished in herbicide management. This is why it is even more critical to consider putting the right product on, at the right time, with the right angle.

“I want to be sure growers are looking at diseases as part of a management plan,” he said. “We are looking at heavy and expensive inputs so to optimize management means they can get a maximum return on the inputs for each particular field.”