“Some Delta cotton producers made as many as 15 insecticide applications for plant bugs in 2007,” says Jeff Gore, Mississippi Agricultural and Forestry Experiment Station research entomologist at MSU’s Delta Research and Extension Center.
“We averaged seven sprays for plant bugs in the Delta in 2007,” Gore says. “This was nearly twice the average number of sprays for 2006 and nearly three times the average number of sprays we were making 10 years ago.”
Gore says plant bug treatments cost $6 to $12 an acre. With already tight profit margins, cotton producers need an economical way to manage plant bugs without losing yields. He says a solution is fine-tuning insect thresholds, or the number of insects found in a field sample that indicates when an insecticide is necessary.
“We’re looking at specific timings for insecticides,” Gore says. “We hope we can reduce one or two applications in many of these situations. Each application eliminated is potentially a big savings on a whole farm basis.”
Was Corn To Blame?
One of the factors behind high plant bug populations in 2007 was increased corn acreage. Corn is a good host plant for the insects. Other factors were a favorable spring for reproduction, adverse weather conditions for insecticide spraying, poor spray coverage and insecticide resistance.
Gore says in response to the plant bug problems of 2007, he will be working closely with other researchers and Extension specialists across Mississippi and the Mid-South to develop a set of best management practices, or BMPs, that will improve insect management in cotton.
“One of the key factors of these BMPs will be to refine insecticide use strategies by reducing spray intervals during times of extremely high pressure, rotating chemistries and improving application efficiency,” Gore says. “Other factors to be considered will be eliminating weeds that act as hosts, minimizing and managing the effects of corn fields adjacent to cotton and variety selection.”
The goal is to reduce the number of insecticide applications and minimize the impacts of insect pests without negatively affecting yields or profits.
Gore came to MSU in November 2007 after working for six years as a research entomologist for the USDA Agricultural Research Service in Stoneville, Miss. Gore received his doctorate in entomology from Louisiana State University in 2001 and is originally from Gadsden, Ala.
Plant Bug Strategies
Joe Street, head of the Delta Research and Extension Center, says with the increased incidence of plant bug damage on cotton, Gore will be a valuable member of the DREC team. He will devise effective methods to control plant bugs and other pests.
“Jeff brings tremendous experience in entomology to our staff,” Street says. “He is well known for his work with cotton pests, and I am pleased to have an individual of his caliber on board.”
Gore’s research will focus on insect pests of cotton, soybeans, corn and peanuts. He also will study the potential for site-specific insecticide applications. Site-specific technology uses coordinates from satellites to apply pesticides only to areas of a field with the highest population of pests, thus reducing spray costs.
“Entomology research with site-specific applications at the DREC has focused primarily on tarnished plant bugs; however, plans are in place to expand that research to also include spider mites,” Gore says.
“We feel that spider mites are an ideal candidate for site-specific applications because early infestations start at isolated locations within a field; their feeding injury to cotton is visually evident; and the miticides used for their control are very expensive.”
The Delta Research and
Extension Center in Stoneville, Miss., provided information for this
article. Contact Dr. Jeff Gore at (662) 686-3252.