Putting a fungicide in the sprayer tank when a glyphosate herbicide application is being made at V5 growth stage of corn is set to explode in 2011. This explosion could occur because of trial results in 2010 that showed a national average eight bushels per acre positive yield response to a fungicide with preventive and curative disease modes of action at V5.

Effingham Equity cooperative, with 11 locations serving southeast Illinois, expects to have between 5,000 and 10,000 acres of corn treated with a fungicide at V5 growth stage in 2011. It is a big jump in acreage from 2010 trials.

"With $7 corn, farmers are more willing to see their way into doing things that might increase yield, compared to $3 corn, when the margin for error is a lot thinner," said Beau Morris, the cooperative's branch manager at Stewardson, Ill.

Agronomists for Effingham Equity are suggesting a three-for-one application that makes sense economically. For a single application cost, growers can get one-or-two product weed control, foliar nutrient (based on tissue testing) and a fungicide for control of anthracnose and other early-season diseases all in one tank mix.

"Not every product can be tank mixed with every fungicide," noted Terry Sorgenfrey, Bayer CropScience technical sales consultant for a section of counties in southcentral Illinois. "The beauty of Stratego YLD is that it has the flexibility to be added to almost any other product in a

tank mix."

The V5 application most common for his Illinois counties in 2011 is likely to be a tank mix of Laudis and glyphosate herbicides plus Stratego YLD fungicide and other nutritional products. The counties have a higher Midwestern average for corn-on-corn production, more and more glyphosate-resistant waterhemp and marestail showing up and consistently have some degree of anthracnose infection from year to year.

The V5 fungicide application in the Effingham Equity geography mainly will target anthracnose. "We've never really worried about anthracnose because we never really had an answer for it," said Morris.

"Stratego YLD applied at V5 is something that could give us good management of the disease."

Morris expects whatever yield advantage that occurs will be because of disease control and also because of "better standability and harvestability" of the corn.

Sorgenfrey has no doubts that there will be a yield advantage — to what degree is always the question. Last year's national average yield trials showed a Stratego YLD application at V5 increased yields 8.3 bushels per acre, and using Stratego YLD at V5 plus another application at R1 resulted in a national average yield increase of 15.2 bushels per acre against non-treated checks.

Sorgenfrey says he simplifies the fungicide use by referring to the V5 application as the anthracnose timing and the R1 application as the gray leaf spot control timing. He noted there are quite a few gray leaf spot-resistant hybrids on the market, but extremely few hybrids that show much, if any, resistance to anthracnose.

"Growers seem ready to invest into an anthracnose application," Sorgenfrey said.

With ag retailers such as Effingham Equity ready to apply three- and four-way tank mix solutions including Stratego YLD, this could be the year that growers everywhere see the value, and this could be the breakthrough year for the V5 application becoming as common as an R1 timing application.

For more information about V5 fungicide application in corn, Sorgenfrey can be reached at terry.sorgenfrey@bayer.com.

Key Issues Perspective: Big increase in V5 fungicide application