Soybean Pest Podcast
In this episode, Matt and Erin interview the 2016 Gunderson Memorial Seminar speaker, Dr. Ric Bessin. Ric is a professor and extension entomologist at the University of Kentucky. His areas of extension and research interests range from row crops to specialty crops, and has a focus on IPM. Their conversation starts off talking about agriculture in Kentucky compared to Iowa.
He also shares observations about early season pests, like wireworms, and moves to brown marmorated stink bug, an invasive species causing havoc in Kentucky. Ric was also a Peace Corps volunteer before graduate school, and where he spent time beekeeping. He shares an interesting story about using bees to help with pain management.
Due to technical difficulty, this is a second take at the podcast today. Matt and Erin start by sharing highlights from the recent International Congress of Entomology (ICE) meeting in Orlando last week. Erin talks about pest resistance issues for corn rootworm and western bean cutworm. Matt summarizes some work on rapid resistance development in agro-ecology systems. Fall nuisance invaders were also briefly discussed, including minute pirate bugs, boxelder bugs and lady beetles. Matt got excited by a recent aphid find on ISU campus this week - aphids and parasitized aphids were on collected from buckthorn. They don't understand the implications for these finds yet, but it is certainly not a common find. Lastly, Matt and Erin are speaking at the upcoming ICM Conference in Ames. Registration details will be posted soon.
Minute pirate bug adult feeding on white fly nymphs. Photo at https://en.wikipedia.org/wiki/Anthocoridae.
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.
[Apologies for the poor sound quality of Erin's microphone]
In this podcast episode, Matt and Erin recap a few extension activities they recently participated in this week. It started with being an "expert" at the Iowa State University display building in the 2016 Farm Progress Show near Ames, IA. Both Matt and Erin helped answer questions about entomology and agriculture, and they also learned from the other displays in the building (something about underwear?). One of the main attractions was a monarch butterfly display and also samples of a new invasive weed, palmer amaranth. Matt also saw a cool UAV display with potential use in site-specific management. Erin also was a judge for a regional crop scouting competition for high school students. It included two teams each from Iowa, Indiana and Nebraska. There are some bright, young agronomists out there. Erin switched gears to talk about pest updates in Iowa, but crops are quickly maturing and the time to make treatments is generally done for this growing season.
The podcast took a break while Matt was on vacation and Erin was on the extension circuit. But they're back and talking about recent pest activity in Iowa. First, Erin shares updates about treating for soybean aphid in northern Iowa. Populations were erratic, as usual, and some fields exceeded threshold in early- to mid-August. A few people noticed poor performance of bifenthrin, a pyrethroid, for soybean aphid. This isn't a huge surprise, given there are pyrethroid-resistant populations in southwestern and southcentral Minnesota in 2015 and 2016. It is important to assess insecticide efficacy and determine potential issues with soybean aphid. In general, soybean are approaching mid- to full seed set throughout Iowa and yield responses are not consistent when applied after full seed set.
In addition, Erin has noted some corn fields with abundant aphid populations. Some fields exceeded 1,000s per plant and were treated with aerial applications last week and this week. Economic thresholds for these pests are not well defined, but Erin has an ICM News article to take into consideration.
Matt and Erin will be at the 2016 Farm Progress Show near Boone, Iowa on August 30. Erin will be at the ISU Event Tent in the morning and have a presentation at 10am. Matt will be there in the afternoon - so stop by and see them!
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.
Don't drought this episode was a good one. Matt shares an update on the Iowa drought and encourages people to use the U.S. Drought Monitor as a tool to measure landscape moisture levels. Matt and Erin transition and talk about pest activity around the state, starting with twospotted spider mite. Erin wrote a recent ICM News article that talks about scouting and managing this pest that favors hot and dry conditions. Spider mites can be first detected around field perimeters and then eventually infest the field interior. Discoloration, webbing and stunted plants are often the result of heavy spider mite feeding. Erin mentioned a new miticide, AgriMek, that has promise for suppressing mites in corn and soybean; find the label here. The conversation switched gears to talk about some corn silk clipping pests, like Japanese beetle and corn rootworm adults. Scouting to determine pest densities and potential interference with pollination is important. Learn more about Japanese beetle ID, scouting and management with an ICM News article.
Twospotted spider mite. Photo by Frank Peairs, www.ipmimages.org.
Bean leaf beetle. Photo by Marlin Rice.
Today, Erin is so excited to tell everyone about her new, 12-page publication called, "Getting to Know the Insects." This publication is geared to youth and new agronomists that want to learn more about how to identify, sample and management field crop insects. It's available for $2 in the ISU Extension Store. Next, Matt and Erin talk about corn and soybean switching to reproductive stages around Iowa and implications for pest scouting and management. In particular, hot and dry weather favors twospotted spider mites, but expected cooler temperatures can promote soybean aphid populations. Erin also mentions a rare pest, redheaded flea beetle, showing up in a cornfield this summer. Read Erin's blog to see feeding injury on corn leaves. Erin also mentioned some upcoming field days at the ISU FEEL demo lab located between Boone and Ames, Iowa. The first is the Crop Management Clinic (13-14 July), which features a number of different topics related to crop production and protection. The second is an all-day workshop on corn insects (29 July). We aren't sure why, but there are a lot of references to MMA fighters in this episode??
Redheaded flea beetle on soybean. Photo by Lewis Veith.
Today, Matt and Erin talk about current pest activity in Iowa. Specifically, the last week was very hot (>90 degrees) and that isn't conducive for soybean aphid growth. So no new detection since the last podcast (but not surprised because aphids don't do well under consistently hot temps). Also, some alfalfa farmers are starting to see potato leafhopper injury. Matt heard about early twospotted spider mite injury in Illinois and that is a concern for extended hot and dry periods. Southeastern Iowa is abnormally dry right now and so be looking for initial spider mite infested along edge rows. Mite injury should not be confused with herbicide injury that is also starting to show up in some soybean fields. Finally, Erin and Matt talk about Pollinator Fest displays at Reiman Gardens. Erin will have the kids make Wikki Stik insects and Matt has prepared a honey tasting station.
Potato leafhopper (Photo by Marlin Rice) and classic "hopper burn" (Photo by Purdue Extension). To learn more about potato leafhopper, read this ICM News article.
Twospotted spider mite (Photo by Frank Peairs) and spider mite injury (Photo by Whitney Cranshaw). To learn more about scouting for twospotted spider mite, read this ICM News article.
Wikki Stik insect art for Pollinator Fest (Photo by Erin Hodgson).
Today, Matt and Erin have so much to talk about in this episode. The multiple phone calls and people stopping by Erin's office can't stop the podcast. Lab members found a few soybean aphids in central and northeast Iowa. This is not too surprising because a few soybean aphids can usually be found in June. Populations are very low, but something to note as the field season continues.
The first soybean aphids of the year were found in northeastern Iowa. Photo by Greg VanNostrand.
The warm winter was helpful to those insects trying to overwinter in Iowa, particularly for bean leaf beetle. For the other crop in Iowa, corn rootworm egg hatch is peaking, stalk borers are moving to corn, and European corn borer egg hatch is also happening now. Then the conversation turned to millipedes - not a typical field crop pest. They talk about field conditions conducive to millipede injury, in addition to other emerging pests like slugs, snails and isopods. Finally, Matt reminded us Pollinator Fest is coming up at Reiman Gardens in Ames on June 25.
Random fact: Millipedes are arthropods within the class Diplopoda. They are distant relatives to insects and arachnids. People who study millipedes are called diplopodologists.
Millipede. Photo by David Cappaert, www.ipmimages.org.