WEST LAFAYETTE, Ind. — Now is the time of year when corn growers need to decide if a fungicide should be applied, and a Purdue University expert has a few guidelines to help in the decision-making process.

“Deciding whether to apply a fungicide is not a straightforward question,” said Kiersten Wise, Purdue Extension field crops disease specialist. “There are several things that must be taken into consideration.”

University research from across the Midwest shows consistent yield advantages from a fungicide application occur when there is a significant amount of disease in a field, Wise said.

“This is the time to get out there and scout and determine the amount of disease in the field,” she said. “This will really help you decide if a fungicide application is justified.”

Wise recommends farmers take into account hybrid susceptibility, the level of disease in the field, previous crop and cropping system, late planting, and if weather conditions are favorable for disease development.

Hybrids vary in their susceptibility to foliar disease of corn, and hybrids susceptible to diseases such as gray leaf spot are at a greater risk of disease development than hybrids with moderate or high levels of resistance, she said.

“As far as limiting yield potential, gray leaf spot is the main disease we are concerned about,” Wise said. “However, if you see a little bit of gray leaf spot in the field when scouting, that doesn’t necessarily mean you need a fungicide application.”

Growers should look through the entire field, consider the type of field and where the lesions are located on the plant, she said.

“Check to see if lesions are on the ear leaf or if the disease is on a few leaves below the ear leaf and determine the percentage of plants affected,” she said. “Fungicide application should be considered on fields where the hybrid is rated as susceptible or moderately susceptible and 50 percent or more of the plants display disease lesions on the third leaf below the ear and higher prior to tasseling.”

So far, Wise said she has seen gray leaf spot on lower leaves in some susceptible hybrids.

When looking at the previous crop and cropping system, it’s important to remember that most fungal diseases, such as gray leaf spot, survive from year to year on crop residue.

“Planting continuous corn or planting corn into high levels of corn residue with no-till will increase the likelihood for a disease to develop,” Wise said.

Late planting across much of Indiana, Illinois and Ohio this spring means the crop is at increased risk of gray leaf spot development, according to research from Iowa State University. Favorable weather conditions for disease development of gray leaf spot are high humidity and moisture levels, as well as moderate to warm temperatures.

Wise cautioned growers to be careful in making the decision about whether to apply a fungicide and also include economics in the list of things to consider.

“It’s an added cost, and with the price of corn right now, we need to make sure that the fungicide application will pay for itself,” she said.

Economic return depends on fungicide application costs, drying costs and the price of corn. Wise said an increase of approximately 10 bushels per acre is needed to pay for the cost of fungicide application with corn priced at $3 per bushel and an application cost of about $30 per acre. As the price of corn increases, the additional amount of yield needed to pay for the fungicide application decreases, Wise said.

So when corn is at $3.50 per bushel and application costs $30 per acre, a yield increase of about 8.5 bushels per acre is needed to pay for the cost of application. If corn reaches $4 per bushel, then a yield increase of about 7.5 bushels per acre is needed to cover application costs.

For more information about determining whether a fungicide application is warranted, contact Wise at 765-496-2107, kawise@purdue.edu

WEST LAFAYETTE, Ind. — Crop producers should start scouting for signs of western bean cutworms this week, according to a Purdue University Extension specialist, after the first signs of the corn pest were recently found in northwestern Indiana.

“Typically at the end of June we start catching our first moths, and that’s what’s happened this year,” said John Obermeyer, Purdue Extension integrated pest management specialist.

Western bean cutworm is a pest that can cause damage to ears of corn. A cluster of about 50 to 100 small, white, pearl-like eggs are laid on the upper surfaces of the top leaves of a plant. They will turn a deep purple just before hatching, Obermeyer said.

Once hatched, larvae get quickly into the corn whorl and eat until ears are formed. Once in an ear, they will eat before cutting out of the ear and dropping to the ground to winter, becoming moths the following summer. Molds often form where the worms have eaten.

Western bean cutworm first showed up in Indiana about three years ago. But in areas that have been dealing with the pest for decades, Obermeyer said, yield losses could be as high as 20 percent, although that is unusual. He expected the losses to be significantly lower in the state, though it will be worst where the insects were observed last year.

Western bean cutworms like sandier soils with continuous corn rotations. They are attracted to fields that soon will or are actively pollinating.

Obermeyer said producers should check 20 consecutive plants for egg masses. Anything higher than 5 percent to 8 percent of plants infested should receive an aerial insecticide, he said. He said Cry1F Bt corn seed also has been effective in controlling western bean cutworm.

“Once we start seeing moths, which we have in the northwestern counties, we know the eggs aren’t too far behind,” Obermeyer said. “Egg scouting is the only chance we have of catching them before they get into an ear.”

Obermeyer said the western bean cutworm is most likely to be seen in northwestern Indiana counties, and as far south as Benton County. One moth was seen on the eastern border of Indiana in Jay County already this year.

WEST LAFAYETTE, Ind. — Even though it’s been an unusually wet spring in Indiana, it was cold enough to limit the conversion of anhydrous ammonia to nitrate during the rainy periods, said a Purdue University expert.

Nitrogen losses should be about average because of the cooler-than-normal temperatures across the state, said Jim Camberato, Purdue Extension soil fertility and plant nutrition specialist.

“If a farmer applied anhydrous in the fall, the average loss would be estimated at about 30 percent of the nitrogen if they did not use a nitrification inhibitor such as N-Serve,” Camberato said. “Fortunately, most Indiana farmers apply their anhydrous in the fall with a nitrification inhibitor, and we estimate the average loss to be about 15 percent of the applied nitrogen.”

A nitrification inhibitor slows the conversion of nitrogen to nitrate — the form that is lost.

“For anhydrous applied in the spring without a nitrification inhibitor, we also estimate 15 percent of the nitrogen to be lost,” he said. “If a nitrification inhibitor is used with spring anhydrous, dependent on when it was put out, losses will be minimal.”

Camberato said farmers who planted shortly after anhydrous application should watch for anhydrous injury, particularly in sandy soils.

The best application of nitrogen is to sidedress UAN (urea ammonium nitrate) or anhydrous UAN by either injecting it into the soil or dribbling it onto the soil surface, he said. If it’s injected at least 2 inches deep, ammonia loss is eliminated. When dribbled on the soil surface, losses of UAN are only about 5 percent of the nitrogen applied.

“A broadcast application of UAN between the corn rows or a broadcast application of urea left on the soil surface have the potential to lose 15 or 30 percent of the nitrogen content as ammonia to the air, so I do not recommend them,” Camberato said. “If you want to leave urea on the surface, then adding a urease inhibitor, such as Agrotain to the urea should be considered.”

However, he said making an injected application of UAN would still be better than adding the inhibitor to urea.

Because nitrogen is relatively expensive compared to grain lately, one should consider the cost of nitrogen and the value of the grain for determining the rate of sidedress nitrogen application, Camberato explained. A Corn Nitrogen Rate Calculator based on recent Purdue research by Camberato and Bob Nielsen, Purdue Extension corn management specialist, is available at http://extension.agron.iastate.edu/soilfertility/nrate.aspx. The calculator is designed to help farmers calculate the economic return to nitrogen with different nitrogen prices and corn prices. For more information on modifying recommendations derived from the calculator, visit http://www.agry.purdue.edu/ext/corn/news/timeless/NitrogenMgmt.pdf

WEST LAFAYETTE, Ind. – Two Purdue University agricultural economists will crunch U.S. Department of Agriculture planting intentions data and share their insights during an online meeting from 7-9 p.m. March 31.

Chris Hurt and Corinne Alexander will discuss the USDA’s “Prospective Plantings” report and offer marketing strategies on the same day the report is issued. Online participants can ask questions electronically and view and print Hurt’s and Alexander’s PowerPoint presentation. The meeting will be conducted using Adobe Connect, a Web conferencing program.

To participate in the live online meeting or watch an archived version later, log onto https://gomeet.itap.purdue.edu/march31outlook. Some county offices of Purdue Extension also plan to host the live Webcast. For more information, contact a Purdue Extension office.

The annual “Prospective Plantings” report estimates how many acres of corn, soybeans, wheat and other crops American farmers expect to plant each year. Acreage projections are based on a survey the USDA conducts with farmers across the country.

“The report is the first indication of what farmers are actually going to plant this year,” Alexander said. Farmers and commodities traders pay close attention to the planting intentions report, she added.

“We expect the report to have a major impact on markets,” Alexander said. “If you think back over the last couple of years, we’ve seen major acreage swings on the order of millions of acres moving out of corn or soybeans, or back into corn and soybeans and wheat, as well. We’re expecting the same sort of massive acreage shifts this year.”

In the 2008 planting intentions report, the USDA estimated that the nation’s farmers would plant 86 million acres of corn, 74.8 million acres of soybeans and 63.8 million acres of wheat. Farmers eventually planted 85.9 million acres of corn, 75.7 million acres of soybeans and 63.1 million acres of wheat.

Large acreage shifts are likely this year, Alexander said.

“We at Purdue are estimating that corn acreage will be down nationwide by about 1 million acres, soybeans will be up by 6 million acres and wheat will be down by 4 million acres,” Alexander said.

Those interested in watching the Purdue online meeting should have DSL/high-speed Internet access. Computers must have Adobe Flash Player installed to receive the Adobe Connect program. A free plug-in download of Adobe Flash Player is available at http://www.adobe.com/products/flashplayer/

When logging in for the meeting, computer users should click “Enter as a Guest,” enter their name and then click the “Enter Room” button. Make sure computer speakers are plugged in and turned on to hear the presentation.

The 2009 USDA “Prospective Plantings” report can be accessed after 8:30 a.m. EST March 31 online at http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID=1136

WEST LAFAYETTE, Ind. — The 2009 edition of the “Corn & Soybean Field Guide,” a pocket reference that covers corn and soybean production issues, is now available for sale.

The guide, created and distributed by Purdue University’s Crop Diagnostic Training and Research Center, is a handy resource for determining stages of plant development and identifying weeds, insects and plant diseases, as well as plant injury and deficiency symptoms. Center director Corey Gerber said pictures in the guide have been especially helpful to its users.

“The photos help identify types of pests, plant deficiencies and injuries, either related to herbicides or weather,” Gerber said. “The guide is small enough that people can take it to the field and use it as a source on the spot.”

The 2009 guide includes a few new items, including updated nitrogen recommendations and photos of early stage lesions for plant diseases on corn. Gerber said these photos would aid crop advisers, scouts and farmers in diagnosing issues early, allowing ample time to manage problems.

The guide is $6 and can be purchased online or by phone. To purchase online, go to http://www.extension.purdue.edu/store and search for product code ID-179. To order by phone, call (888) EXT-INFO (398-4636).

WEST LAFAYETTE, Ind. — Crop growers now have access to the 2008 variety trial yield results for corn and soybean varieties tested in Indiana.

“As with a lot of people, this year we had challenges, but the yields are much better than anticipated,” said Phil DeVillez, director of Purdue’s Crop Performance Program.

DeVillez and his team tested 240 corn hybrids at 12 sites and about 200 soybean hybrids at nine sites.

Yield data is available at the Purdue Crop Performance Program Web site, http://www.agry.purdue.edu/pcpp/. The variety trial results are free for farmers.

“The best thing a grower can do when contemplating varieties, is to compare this year’s data to last year’s data,” he said. “Always look at multi-year data.

“Something that was on top last year could be in the middle of the pack or even on the bottom this year, in terms of performance. It all depends on the planting date, growing season and the rain patterns.”

DeVillez said the past two years have been very different. If a variety is at the top in terms of performance both last year and this year, then you can feel confident about it being a good variety for the area.

For additional information and questions about how to interpret the data, contact DeVillez at (765) 583-1406 or pld@purdue.edu.

“We learned that good yields can still be achieved with late planting,” he said. “We replanted three of our locations (Butlerville, Shelburn and Vincennes) and probably should have replanted a fourth, but we just didn’t have enough time.

“We planted our plot here in West Lafayette May 29, which is a good month behind normal, so we didn’t expect yields to be very good on that plot. Our last planting date was June 12.”

DeVillez said the plot at the Purdue Agronomy Farm yielded more than 200 bushels of corn an acre. He attributes the surprisingly good yields to September’s warm weather, as well as improved genetics and the insect resistance with which they’ve been bred.

“If you look back, September was really warm and that helped us catch up in terms of growing degree days,” he said. “Because the crop was planted late and was still maturing, it worked out quite well, other than putting us behind for harvest.

“We didn’t start harvest until Oct. 1. Typically, we start sometime during the first week of September.”

DeVillez said the data is very representative of the state this year.

This also was the first year for the Farmer Nominated Variety Program, which is a partnership between the Indiana Soybean Alliance and Purdue Agronomy. This year, 16 soybean varieties were entered into the trials and DeVillez hopes to see that number grow next year. The program, designed to ensure producers have an objective source of information about the plant health and yield characteristics of individual soybean varieties, is funded by checkoff dollars.

“It basically allows farmers to have input about what varieties will be tested,” DeVillez said. “If you have a favorite variety that’s not included in the program because the company doesn’t participate or chooses not to put it in the test, then you can nominate it.”

For more information about the Farmer Nominated Variety Program, contact the Indiana Soybean Alliance at (800) 735-0195 or DeVillez.