What’s the deal with pest resistance?
Pests – insects, disease and weeds -- are a regular part of life. For large areas, our pest removal practices have included spraying safe pesticides or relying on plant genetics to manage them. But many pests can reproduce quickly and often, allowing them to evolve and develop tolerance to some of our easiest, cheapest and most effective management tools. Some pests are completely tolerant to some pesticides. When this occurs, it is called pest resistance, because they can now resist and survive a specific management tactic that previously controlled them.
Pest resistance is a natural process. However, when it comes to something as valuable as our food and when there’s no easy way to fight a pest, it can lead to yield reductions and increasing costs. Farmers, landowners, scientists, private businesses, and groups of individuals are finding ways to preserve our management tools, prevent pest resistance, and develop management strategies for already resistant pests.
The two most important pests that reduce soybean yield (nematodes and aphids) are evolving, becoming resistant to commonly used pest management tools. This workshop will provide research-based, sustainable pest management recommendations for the control of soybean cyst nematode and soybean aphid. Information provided will include updates on the status of resistant pest populations in Iowa and hands-on demonstrations of sampling and managing both pests.
Soybean cyst nematode (H. glycines) is the most damaging pathogen of soybean in the United States and Canada. The main management strategy has been to rotate soybean crops with non host crops. However, this strategy has not proved always effective, leaving the need for more study and application of nematode-protectant seed treatments.
The goal of the study was to determine the effectiveness of two different seed treatments on soybeans: ILeVO (fluopyram) and VOTiVO (Bacillus firmus I-1582). These two seed treatments coat the soybean seeds in active ingredients (AI) to help the plants fight different pests and diseases, while also using a less amount of AIs as it’s applied directly to the seed and root area of the plants and not across an entire field.
The researchers grew soybeans and inoculated the roots of the treated and untreated soybeans with H.glycines at various soil depths. The data supports that ILeVO fights against H.Glycines, but gets less effective as the roots grow away from the treated seed. ILeVO also significantly reduced second-stage juvenile (J2) SCNs compared to the untreated soybean seeds. ILeVO treated seeds also significantly reduced the movement of J2 populations compared to the groups of non treated seeds and groups of just the J2 populations. VOTiVO had no effect on the measured parameters in the study.
This study was published in 2019. For the whole study, click here.
DES MOINES – Iowa Secretary of Agriculture Bill Northey, Iowa State University College of Agriculture and Life Sciences Associate Dean John Lawrence and Iowa farmer Larry Buss of Logan today announced the release of the Iowa Pest Resistance Management Plan. A video of the announcement is available here.
Version 1 of the IPRMP is an Iowa-specific plan that seeks to engage farmers on the issue of pest resistance management with the goal of keeping technology and tools such as pesticides, seed treatments and biotechnology products and native traits available and effective.
A research team led by Iowa State University has solved part of a mystery important to battling the most serious threat to U.S. soybean production, the soybean cyst nematode — a pathogen responsible for more than $1 billion in reduced yields each year in this country alone.