This podcast episode focuses on a few recent pest updates, like soybean aphid, twospotted spider mites, and a mix of defoliators. Matt talks about spider mite activity in some of his research plots and also in fields near Brookings, SD. Erin notes soybean aphid activity is down throughout Iowa and they both revisit the economic threshold for this common pest. To read more information about why the economic threshold for soybean aphid remains consistently at 250 per plant, read this webpage co-authored by many university entomologists. Finally, Matt shares a research update on the release of parasitic wasps that like to feed on soybean aphid.
Today, Matt and Erin talk about noteworthy news items related to field crop pest management. But first, they talk about upcoming meetings they plan to attend. Both are attending the ICE (International Congress of Entomology) meeting in Orlando next week. And both plan on speaking at the annual ISU Integrated Crop Management Conference in Ames (Nov 29 - Dec 1). Erin will talk about a management plan for soybean aphid, particularly with suspected pyrethroid resistance in Iowa. Matt plans to talk about pollinators in field crops. In Minnesota, the governor proposes restrictions on neonicotinoids in agriculture and the implications for that are largely not understood. Also, the recent merger discussions between Bayer Crop Science and Monsanto also could change the ag industry in the U.S. and around the world.
It's a new beginning for the podcast - Season 8 starts today! Matt and Erin have a bit of random conversation at the beginning like usual. But they eventually provide a summary of the recent new of an organophosphate, chlorpyrifos. The EPA has been dealing with a petition to revoke tolerances for this widely-used insecticide. The EPA will not move forward with restricting chlorpyrifos in any crop; this could be important as farmers make product choices for 2017. Erin wrote a recent ICM Blog about it. Matt shared updates about his recent travels to the S1055 Soybean Entomology Working Group meeting in Memphis where he compares soybean production in the North Central Region to the South. Surprise - it's a lot different! Erin wraps up by providing overwintering mortality predictions for bean leaf beetle. The 2016-2017 winter was moderate and about half of the beetles are expected to survive. Read more in her recent ICM News article.
Bean leaf beetle adult. Photo by Winston Beck, ISU.
It's been a few weeks, but Matt and Erin have a new episode out today! Erin starts off by providing a statewide update on soybean pest populations in August. Good news is that most fields had low pest pressure in 2018. Matt shares his impressions of a recent court ruling that will ban chlorpyrifos use in the U.S. The episode title is a play off of Warren Zevon's song, "Lawyers, Guns and Money" from 1978.
Soybean aphid management has relied heavily on foliar insecticides to protect yield since 2000. In 2016, performance issues have been documented in commercial fields and research plots in northern Iowa counties. With support from the Iowa Soybean Association, we are exploring insecticide resistance for soybean aphid in Iowa and describing the mechanism of resistance. Laboratory bioassays identified field-collected population’s evolved resistance to pyrethroids. Read more about Monitoring soybean aphid resistance to lambda-cyhalothrin and identification of mutation associated with insecticide resistance