In this episode, Matt and Erin start by talking about foliar insecticide sprays for soybean aphid. Erin has a large efficacy evaluation program and screens many different products every year. She publishes the results in a Yellow Book (see previous editions here: http://www.ent.iastate.edu/soybeanresearch/content/extension). Then Matt talks a bit about corn rootworm biology and why that might be important in Iowa soybean.
In this episode, Matt and Erin break down a recent ruling to vacate the unconditional registration of sulfoxaflor. In other words, the EPA registration for sulfoxaflor, in products like Transform and Seeker, was overruled in U.S. court.
Read more about the court decision here: http://earthjustice.org/sites/default/files/files/sulfoxaflor-opinion.pdf
Read more about why EPA approved the registration of sulfoxaflor here: http://pesticides.supportportal.com/link/portal/23002/23008/Article/35618/Why-did-EPA-register-sulfoxaflor-I-heard-it-harms-bees
Learn more about insecticide groups here: http://www.irac-online.org/documents/moa-classification/
Matt and Erin have a special guest on this podcast to help understand life cycle assessments. Dr. Kurt Rosentrater is an engineer and associate professor at Iowa State. Kurt explained the basics of conducting a life cycle assessment, including assumptions and resulting complications that come with this tool. They focused on a recent example looking at environmental impacts in four major crops. Here is the link to the paper so you can follow along with figures: http://www.ingentaconnect.com/content/iop/erl/2015/00000010/00000009/art094016. The assessment showed freshwater ecotoxicity impact in soybean increased 3-fold from 2002 to 2012. The authors claimed the insecticides used to control soybean aphid was an important factor. Corn, cotton and wheat did not have a significant increase of impact over the study duration. Learn more about Kurt's research and teaching program here: http://www.abe.iastate.edu/kurt-a-rosentrater-assistant-professor/.
Soybeans are going into the ground, and Matt and Erin have started a new podcasting season. They talk about early-season soybean pests, like black cutworm and bean leaf beetle, and the likelihood of seeing injury this year. Read more about the predicted cutting date for black cutworm here:
http://crops.extension.iastate.edu/cropnews/2016/05/black-cutworm-scouting-advisory-2016. They also spend some time highlighting some new people and research projects going on this summer. Finally, Matt talks about a recent publication that looks at the probability of breaking even with different inputs.
It's the first podcasting episode of 2017! Matt and Erin talk briefly about a few topics related to insecticides today. First, Erin recaps the findings of her insecticide resistance project from 2016. A field sprayed twice with a pyrethroid (bifenthrin) did not have efficacy against soybean aphid. She conducted an assay and discovered elevated resistance ratios for bifenthrin and lambda-cyhalothrin. Distinguishing insecticide group will become important for future growing seasons so farmers can prolong the efficacy of pyrethroids and organophosphates. Learn more about insecticide groups and resistance management at the IRAC website. Matt shared updates on pending EPA approvals of existing insecticides. Chlorpyrifos, an organophosphate, had an open comment period that closed January 17, 2017; read more about the health risk assessment for chlorpyrifos. In addition, the EPA has four public comment dockets open now regarding pollinator-only risk assessments for the neonicotinoid insecticides clothianidin, thiamethoxam, and dinotefuran.
Erin and Matt are speaking at the ISU Crop Advantage Series this month. Find locations and registration details here. Erin is also speaking on a resistance management panel at the 2017 Iowa Soybean Research Conference on February 8, 2017.
Watch an IRAC video on how insecticide resistance happens!
In the last episode of season 7, Matt and Erin talk about two new insecticide options for soybean aphid in Iowa. Movento and Sivanto by Bayer CropSciences are products that target fluid-feeding pests, like aphids, and are considered reduced-risk options compared to broad spectrum insecticides. Movento is a Group 23 and Sivanto is a Group 4D. To learn more about these insecticide groups, visit the IRAC website.
It seems like a long time since the last episode and that's because it was! Matt and Erin are back to talk about pest updates in Iowa. Drought stress throughout much of the state has been ideal for twospotted spider mite. Erin reports Some injury has been observed in corn and soybean this summer. Treatments are going on now throughout some southern Iowa counties. In addition, soybean aphid continues to be an erratic pest. Some populations are building up in northern Iowa counties, but most fields are not reaching the economic threshold in July. Matt elaborates about high numbers of Japanese beetle and they talk about the use of pheromone traps as a management tool. Finally, Matt talks about a new Science research paper that has inconsistent data on the effect of neonicotinoid seed treatments on wild and managed bees in Europe.