As production practices evolve, the methods used by scientists and farmers to attack and conquer insect problems in soybeans also evolve.
“One of the biggest factors is that the production system for growing soybeans has drastically changed and it’s forcing us to re-evaluate the damage caused by insects,” said Gus Lorenz, Extension entomologist for the University of Arkansas Division of Agriculture.
A tool farmers have in their arsenal to control insects is insecticide seed treatment. Most seed is treated by the seed company or seed distributor before the grower picks it up.
“The use of insecticide seed treatment in soybeans is something we really pioneered in Arkansas,” Lorenz said.
Insecticide seed treatment is making a positive impact on soybean production in Arkansas. In the beginning, others were skeptical about the impact seed treatment could have on controlling insects. However, as soon as other states started testing the treatments, they got the same results Lorenz did. In fact, Lorenz and his Mid-South peers have conducted more than 100 replicated trials since 2008.
“I would say that about 80 percent of the time in these trials we saw a net profit with the use of the treated seed,” said Lorenz. “In other states, that control may be for thrips, root worms, or another insect, but the overall effect is that everyone is seeing insect control and increased vigor.”
Arkansas producers are seeing a positive effect on the control of grape colaspis.
“The results we’ve been seeing the past five or so years are increased health and vigor of the plants and, most importantly, increased yield.”
Insecticide seed treatments appear to have the most value for crops that are planted early.
“The seed treatments help the plant better manage the stress of being planted early and being exposed to stressful field conditions, whether it’s too hot, too cold, too wet, etc.,” said Lorenz. “It’s just about stress management and the seed treatments do that.”