LSU AgCenter soybean specialist Ronnie Levy talks about optimizing soybean yields at the Dean Lee Research and Extension Center field day on July 17. Photo by Olivia McClure

Josh Lofton, LSU AgCenter agronomist, points at a blackbird flying overhead at the Dean Lee Research and Extension Center field day on July 17. Blackbirds feed on grain sorghum heads, which makes ratoon cropping difficult. Photo by Olivia McClure

LSU AgCenter research associate Randall Landry shows johnsongrass to participants at the Dean Lee Research and Extension Center field day on July 17. Johnsongrass is difficult to control in grain sorghum, but a new herbicide called Zest could help solve this problem. Photo by Olivia McClure

News Release Distributed 07/18/14

ALEXANDRIA, La. – Louisiana farmers got an update on a variety of research projects at the LSU AgCenter Dean Lee Research and Extension Center's 13th annual row crop field day. The event, held on July 17, attracted about 200 attendees.

Dan Fromme, AgCenter cotton and corn specialist, said Louisiana cotton acreage is up to nearly 200,000 acres, which is vast improvement over 2013's record low of 125,000 acres. He expects yields to be excellent this year — but perhaps not as high as last year's 1,200 pounds per acre — because insect pressure has been light, and there has been timely rainfall.

There are about 420,000 acres of corn in Louisiana, Fromme said, which is down significantly from 700,000 last year. Fromme attributes the decrease to "disappointing" corn prices.

AgCenter entomologist David Kerns said tobacco thrips, which are a prevalent pest of cotton, have developed resistance to the Cruiser seed treatment. Farmers who used Cruiser need to watch closely for thrips, he said. This year is also "a big boll worm year," Kerns said.

Spider mites are less of a problem this year, but Kerns said they have developed strong resistance to abamectin.

"If you have them, don't rely on abamectin," Kerns said. "Spray with it once, then switch your chemistry to something like Portal or Zeal."

AgCenter soybean specialist Ronnie Levy discussed optimizing soybean yields by adjusting planting dates. Five or 10 years ago, no one thought of planting before May 5, he said, but planting as early as March 21 could mean better yields because the weather is cooler. In hot weather, plants cannot capture as much moisture.

Earlier-planted soybean plants are shorter in stature but produce just as many pods, Levy said. He is working to identify which varieties are best suited for early planting.

Josh Lofton, AgCenter agronomist, talked about research being conducted by Rick Mascagni, AgCenter agronomist at the Northeast Research Station in St. Joseph, on ratoon crops of grain sorghum. Many growers are interested in getting a second crop without replanting, he said, but complications like blackbirds and anthracnose disease sometimes mean ratooning is not worth the effort. He said Mascagni is studying inputs that may make ratooning more feasible.

Lofton is reevaluating recommendations for how many sorghum seeds should be planted per acre. Currently, the AgCenter recommends 75,000 seeds per acre, but 60,000 seeds produce similar yields but on larger grain heads, Lofton said.

Beatrix Haggard, AgCenter soil specialist, told attendees about the soil profile of central Louisiana and how it influences their crops. Soils in central Louisiana contain clay molecules that enable them to hold onto nutrients.

Brandi Woolam, AgCenter research associate, said it is important to triple rinse spraying equipment to avoid damaging plants. Even small amounts of leftover herbicides like Dicamba can cause cupping of leaves and swollen stems, especially in soybeans.

Research associate Randall Landry discussed DuPont's new Zest herbicide, which is not commercially available yet but effectively controls johnsongrass in grain sorghum. This is a breakthrough because johnsongrass is nearly impossible to control in grain sorghum, according to AgCenter weed scientist Daniel Stephenson.

AgCenter plant pathologist Trey Price said southern rust has surfaced in corn in Louisiana, so farmers should scout for it, especially if they planted late. There have been few major issues in soybeans, cotton and sorghum this year, but work to develop varieties resistant to various diseases continues.

Gerald Myers, AgCenter plant breeder, told attendees about the AgCenter's new grain sorghum breeding program. Myers said he is looking at more than 400 lines of grain sorghum from around the world to identify molecular markers that "may allow us to take care of problems we have here in Louisiana."

Julien Beuzelin, AgCenter entomologist, said the Mexican rice borer is spreading through Louisiana and is a problem for rice, sugarcane and non-Bt corn. The white sugarcane aphid population has increased this year, he said. The aphids can prevent heading in grain sorghum and leave a sticky honeydew that makes harvesting difficult. Louisiana has received a Section 18 permit for Transform to control the aphids.

AgCenter entomologist Jeff Davis advised attendees to avoid using acephate to control green and Southern stinkbugs but rather save it for redbanded stinkbugs that arrive later in soybean season. Redbanded stinkbugs in Louisiana have begun developing resistance to acephate, however, so Davis said it is best to do three applications of different insecticides.

Glen Gentry, AgCenter animal scientist, gave an update on research to control the growing feral hog population, which has reached about 500,000 statewide and is causing significant damage to agriculture. Researchers have been testing a bait containing sodium nitrite, which is toxic to hogs, as well as applying creosote to trees, which lures hogs into nearby traps. Feral hogs reproduce rapidly, Gentry said, so at least 60 percent of hogs must be removed just to maintain a steady population.

Rogers Leonard, AgCenter associate vice chancellor for plant and soil sciences, encouraged farmers to attend an EPA listening session on proposed changes to the Clean Water Act on July 30 in Winnsboro. A similar meeting was held in Crowley on July 9.

Bill Richardson, LSU vice president for agriculture and dean of the College of Agriculture, said the Dean Lee Center is critical to the AgCenter's future in both research and extension. He said LSU-Alexandria will begin offering various agriculture courses as part of a new agriculture concentration. A similar program at LSU-Eunice is in the works.

"It's important to expose our students to opportunities in agriculture because they are the future of the research you heard about at the field day today," Richardson said. "There's high demand for trained ag scientists and professionals. We want to do everything we can to give these young people the tools they need to be successful in agriculture careers."

Olivia McClure