SAES-422 Multistate Research Activity Accomplishments Report

Sections

Basic Information
Additional Info

Status: Approved

Basic Information

Project No. and Title: NC_old246 : Ecology and Management of Arthropods in Corn
Period Covered: 01/23/2019 to 01/23/2020
Date of Report: 04/02/2020
Annual Meeting Dates: 01/21/2020 to 01/23/2020

Meinke, Lance (lmeinke1@unl.edu)- University of Nebraska; Fuller, Billy (billy.fuller@sdstate.edu)- South Dakota State University; Deans, Carrie (dean0179@umn.edu)- University of Minnesota; Smith, Jocelyn (jocelyn@uoguelph.ca)- University of Guelph; Krupke, Christian (ckrupke@purdue.edu)-Purdue University; Tooker, John ( tooker@psu.edu)-Penn State; Ostlie, Ken (ostli001@umn.edu)- University of Minnesota; Porter, Pat (p-porter@tamu.edu)- Texas A&M; Davis, Holly (holly.davis@ag.tamu.edu )-Texas A&M; Owens, David (owensd@udel.edu)- University of Delaware; Schaafsma, Art (aschaafs@uoguelph.ca)- University of Guelph; Zukoff, Sarah (snzukoff@ksu.edu )- Kansas State University; Peterson, Julie ( julie.peterson@unl.edu)- University of Nebraska, Lincoln; Coates, Brad (Brad.Coates@ars.usda.gov)- USDA-ARS; Shields, Elson (es28@cornell.edu)- Cornell; Hellmich, Rick (Richard.Hellmich@ars.usda.gov)- USDA-ARS, Iowa State; Villanueva, Raul ( raul.villanueva@uky.edu)- University of Kentucky; Tillmon, Kelley (Tilmon.1@osu.edu)- Ohio State University; Kesheimer, Katelyn (kak0083@auburn.edu)- Auburn University; DiFonzo, Chris (difonzo@msu.edu)- Michigan State; Pereira, Adriano (pereiraa@missouri.edu)- University of Missouri; Hibbard, Bruce (Bruce.Hibbard@ars.usda.gov)-USDA-ARS; Dively, Galen (galen@umd.edu)- University of Maryland; Paula-Moraes, Silbana (paula.moraes@ufl.edu)- University of Florida; Reisig, Dominic (ddreisig@ncsu.edu)- North Carolina State; Barbosa dos Santos, Izailda (barbosad.izailda@ufl.edu)- University of Florida; Storer, Nick (nicholas.storer@corteva.com) -Corteva Agriscience; Oyediran, Isaac (isaac.oyediran@syngenta.com) - Syngenta; Sethi, Amit (amit.sethi@pioneer.com) - Corteva Agriscience; Welch, Kara (welch.kara@epa.gov)-EPA; Pilcher, Clinton (clint.pilcher@corteva.com)- Corteva Agriscience; Mitchell, Paul (pdmitchell@wisc.edu)- University of Wisconsin, Madison; Hurley, Terry (tmh@umn.edu)- University of Minnesota; Carroll, Mathew (matthew.carroll1@bayer.com)- Bayer Crop Science; Gander, Jody (jody.gander@bayer.com)- Bayer Crop Science; Crespo, Andre (andre.crespo@corteva.com)- Corteva Agriscience; Jensen, Bryan (bmjense1@wisc.edu0- University of Wisconsin; Darlington, Molly (mdarlington@huskers.unl.edu) - University of Wisconsin; Dubey, Aditi (aditid@umd.edu)- University of Maryland; Huang, Fangneng (fhuang@agcenter.lsu.edu)- Louisiana State University Ag Center; Luis Hurat-Fuentes, Juan (jurat@utk.edu)- University of Tennessee; Hamilton, Christina (christina.hamilton@wisc.edu)- NCRA/University of Wisconsin, Madison; He, Kanglai (hekanglai@caas.cn)- Institute of Plant Protection, Chinese Academy of Agricultural Sciences; Gassmann, Aaron (aaronjg@iastate.edu)- Iowa State University; Wright, Bob (rwright2@unl.edu) - University of Nebraska; Spencer, Joseph( spencer1@illinois.edu) - University of Illinois; Ruberson, John (jruberson2@unl.ed)- University of Nebraska; Hamby, Kelly (kahamby@umd.edu) - University of Maryland; Wechsler, Seth (seth.wechsler@usda.gov)- USDA-APHIS; Farhan, Yasmine (yfarhan@uoguelph.ca)- University of Guelph; Seiter, Nick (nseiter@illinois.edu) - University of Illinois; Miller, Nick (nmiller11@iit.edu)- Illinois Institute of Technology; Swoboda Bhattarai, Katie (kswoboda3@unl.edu)- University of Nebraska-Lincoln; Cummings, Matt- Canadian Food Inspection Agency; Bradshaw, Jeff ( jbradshaw2@unl.edu)- University of Nebraska; Brown, Zack (zack_brown@ncsu.edu)- North Carolina State University

Brief Summary of Minutes of Annual Meeting

Vip3A protein source discussion – Juan Luis Jurat-Fuentes

- can manufacture Vip3Aa39, 95% similar to Vip3aA20 and Vip3Aa19. He can sell, but would prefer to be involved in the research. Perhaps involve him in grant writing process.

Regional Bt trait/technology fees comparison – Christian Krupke

- Seth Wechsler- agricultural economist involved with project and works for APHIS. Lots of variance across regions and traits are expensive for growers. More traits cost the grower more. Looking at the data, the price differences across regions do not appear to be based on pest abundance or trait efficacy.

EPA Scientific Advisory Panel on Lepidoptera Bt Resistance

- SAP concluded that sentinel plots were cost prohibitive, but Galen mentioned he had surveyed his collaborators and it would only be 3K per location. Vip should be prohibited in southern US corn. Encourage growers to plant non-Bt refuge in southern US and encourage companies to provide good yielding non-Bt hybrids.

Kara Welch, EPA IRM

- Presented on The Unified Website for Biotechnology Regulation that came from Executive Order. Trying to streamline regulatory process for biotech products. They will be opening up comments for new rules on gene edited PIPs soon. Expedited review process for products that come in as “low risk PIP” (not ready to define that publicly yet, but the basis for starting is gene editing that could have happened by a natural process). Contact point is Alan Reynolds.

- Going to open up 60-day comment period soon to SAP and NC246 can respond. Will include letters already written at that time. It would be most impactful to provide one letter from NC246 and additional letters from each of us. They will work on making public data more easily available.

European corn borer and Cry1F – Jocelyn Smith & Art Schaafsma

- Bt resistance in European corn borer in Nova Scotia. All populations were susceptible to Cry1Ab leaf tissue, but four Truro populations took longer to die on Cry1Ab tissue compared to other populations. Wonders if there is a little cross resistance already. Replaced with Optimum Intrasect (Cry1Ab + Cry1F) in the region. Herculex still being sold in Manitoba during 2019, but CFIA has requested phase out of single trait hybrids.

- Conversation with ABSTC on ECB resistance- Amit Sethi; Corteva. Also found resistance. Action item proposed was to look for “island” areas where fields might be small or lots of dairy production to see if Herculex hybrids are currently being sold (is there part for a paper here? Growers in smaller areas have less access to technology from seed producers?). Also look at areas where ECB has historically been a problem. Look for activity in other host crops, as well.

Conventional insecticide use in rootworm management programs: status and challenged

- Lance Meinke- what is the role of soil applied insecticides for rootworm management? Centered largely around continuously planted Bt corn. No new Bt for RW in the next 5-10 years except for SmartStax Pro and insecticide product availability limited. Looked at soil applied insecticides with resistant and susceptible WCR. Western Nebraska populations the soil insecticides failed on (from resistance), while eastern Nebraska the insecticides worked. Ramifications for soil applied insecticides and foliar insecticide interactions. Revisiting BMP and IRM to mitigate resistance. Good for IPM if populations are reduced with insecticide (easier for IPM to work), but questionable value for IRM. For example, allows growers to use Bt traits longer and increase selection pressure. Souza et al. 2019- Western corn rootworm pyrethroid resistance confirmed by aerial application simulations of commercial insecticides.

- Aaron Gassmann- WCR Bt resistance. When fields were categorized as current problem, past problem, rotated, etc. resistance wasn’t any different. In response to resistance, growers don’t rotate, but switch to pyramids and soil-applied insecticides. Now there is resistance to pyramids (mCry3A + eCry3.1Ab, as well as Cry3Bb1), due to cross resistance. Single traited Cry34/35Ab1 resistance in some population, as well as Cry34/35Ab1 + Cry3Bb1 pyramid. Therefore, some farmers have resistance to all traits. Seems like the mitigation has led to the evolution of this resistance. Soil-applied insecticide reduces injury to Bt corn for resistant WCR. Unfortunately, there is substantial survival for resistant insects on Bt even when insecticides are present. So while the roots are protected, resistance is still being selected for.

- Matt Carroll with ABSTC thoughts- except in a limited set of conditions, insecticides do not have significant IRM value. To their knowledge, no company is actively promoting them for IRM. Primary BMP is crop rotation, then pyramided product or non-Bt corn, then as a third option additional control tools (soil insecticides, seed-applied insecticides, chemigation). Discussion around mitigation of resistance, since there is some question about using these BMPs for that.

Special Topic Area: Neonicotinoid and other seed treatments

- Aditi Dubey (U. of Maryland)- used insecticide seed treatments in crop rotation. Insecticidal seed treatment persistence in soil was low, but highest in 3rd year of study after corn. Impacts on non-target arthropods were low. Greater community level impacts in wheat and corn compared to soybean. Corn, saw increases in spider abundance with insecticide, maybe because it was easier to catch intoxicated prey, but who knows. Wheat, the effect was stronger and parasitoid wasps of aphids were most strongly reduced in both insecticide treatments (imidacloprid and thiamethoxam). Was not caused by host scarcity, but likely from insecticide in aphid. Delayed effect into spring. Her theory is that either titer was too low in spring to impact aphid, but impacted parasitoids, or there was a carryover effect from the fall (killed them in the fall and fewer in the spring). No impacts on yield since pest pressure was low.

- John Tooker- mentioned study showing that neonics impacted collembolans, which decreased residue decomposition. This in turn can increase slug populations.

- Open forum on seed treatments led by Christian Krupke. ABSTC cannot comment because it could be anti-competitive and it is not within its charter. Discussion on seed treatments ensued. We need to submit these questions individually to each company for discussion.

Special Topic Area: Ear-feeding Lepidoptera and seed blends

- Pat Porter presentation- experiment demonstrates lots of cross pollination with RIB. Also looked at which kernels expressed which toxin when they pollinating. 2 out of 3 years earworm numbers reduced by RIB ears. Ear feeding insect like earworm would experience mosaic of non-Bt and Bt kernels. Especially problematic with earworms resistant to Cry toxins.

- Julie Peterson- WBC larval movement. 3 distinct periods 1) egg mass to tassel as neonate; 94% stay within a 40cm range- horizontal; 2) tassel to ear; movement distance bigger, 9% 120-160cm and even 1 larva to 9.2ft- horizontal; 3) away from ear; 37% 0-40cm and most spread up to 160cm- horizontal. This movement experiment done in a low density non-Bt scenario. High density scenario they move even farther. What about RIB scenario? Larvae may be more likely to abandon Bt plants than non-Bt plants. Neonates silked more when exposed to Bt.

- Carrie Deans at U of Minnesota- lepidopteran nutrition and implications for resistance monitoring. Differential levels of protein and carbohydrates in different cotton tissue types and changes throughout the season. Bollworm prefers to feed on slightly proteinaceous diet (1.6:1 P:C) ratio. Saw differential response to diet by different field-collected populations. Population and genetic background are important for resistance monitoring. No effect of diet on pupal mass. Diet effects on developmental time. Mortality rate decreases for neonates that are delayed exposure 24 hours Cry on regular diet compared to those placed right on diet with Cry.

- Fangneng Huang- larval movement of Helicoverpa zea in RIB with Vip. Did not recover larvae from pure Vip stand. Very few larvae move in pure non-Bt. 30% reduction of larvae in RIB. Also looked to see if there is Vip resistance in earworm.

- Matt Carroll ABSTC- refuge compliance low in southern US and limited in ways to improve refuge compliance. Modeled durability of Vip with RIB (20%) and Cry resistance in earworm. Relative to a structured refuge, their model says improved durability relative to a structured refuge, even when complete dominance is assumed for seed blend refuge.

- Pat Porter Vip3Aa39 for official testing for Vip3Aa19 and Vip3Aa20. Juan Luis says Cry1Ac is used as a proxy for Cry1Ab and Cry2Ab2 is used as a proxy for Cry2Ae. Isaac Oyediran mentioned that Syngenta is ready to provide Vip, but want to be sure that it’s being used for the correct purpose.

Update and discussion on industry “relaxed” research agreements

- Pat Porter clarified who in the companies are responsible for taking on the agreement in the company. Suggestion to clarify some language describing where lyophilized tissue or protein will be determined.

Holly Davis is secretary for next year. Next year’s meeting will be in Pensacola, FL (hosted by Silvana Paula Moraes) and the following year will be in Aubrun, AL (hosted by Katelyn Kesheimer)

Special Topic Area: Economic, social, and psychological aspects of resistance management- Zach Brown on economic, social, and psychological aspects of resistance management.

- Spatial economic spillovers in WCR resistance to Cry3Bb1. No evidence that prior Cry3 use led to higher UXI. He’s unsure, but it could be that CRW predation or some density dependent effect might be important. Because they didn’t find that prior Cry3 use led to higher UXI, they couldn’t find resistance using this model. Point was made that this is very coarse grained data and likely resistance cropping up on a much more fine-grained (like field) level.

- Farmer demand and areawide pest suppression for crop protection traits. As price premium decreases, the quantity of the seed purchases increases. How can we use this model for pest management? A 1% price increase resulted in <1% long-term demand decrease with pest suppression feedback. Without the feedback a 1% price increase resulted in a >1% long-term demand increase. Areawide pest population growth suppression is a public good.

- Evaluating social marketing strategies for addressing pesticide resistance- pilot program by Monsanto using social marketing to convince growers to plant refuge. 2.6-5.8% increase in refuge planted and 12.6% increase in growers planting any refuge in campaign counties the year after the program. Some evidence that smaller growers responded more to program. Effect decayed over time and was not persistent. No statistical effect on refuge compliance and refuge area likely because large growers were less responsive. Most significant effect was mobilizing growers to plant some refuge. Brown 2018 J. Agricul. Econom.

- ABSTC- Clint Pilcher. ESA/WSSA science policy tour during 2019. Goal was to get a new perspective on the development and implementation of local, voluntary, and community based social issues surrounding resistance. They talked about the importance of trust in the social science aspect. Value similarity is more important that competence or facts to gain trust. Most stakeholder groups share similar values so alignment is highly probably if correct approach is used. (protectiowacrops.org) Suggestion was to bring in stakeholder groups to dialogue.

Special Topic Area: Biological control as an IPM and resistance management tool

- Elson Shields- entomopathenogenic nematodes for control of corn rootworm. Nematodes persist even with Bt corn. He thinks they are feeding on intoxicated larvae. Sent nematodes down to Texas, they persisted and reduced injury on non-Bt corn. He thinks it might be able to stand alone on non-Bt corn in the northeastern US, but at a minimum can be a good partner with Bt corn everywhere to extend durability of Bt. Action item: he has 2-5 years before retirement, but if you want in on the party it would be good to get in now.

- Katelyn Kesheimer- EPNs for billbug in bahiagrass. Bahiagrass dieback was attributed to bahiagrass billbug- Sphenophorous coesifrons. Problem is that is lays eggs in grass stem and larvae feed on tillers and roots. The larvae are protected in the stem and difficult to reach. She put out untreated and two different mixes of nematode species. Applied early June, hot and dry, and severe drought followed. Couldn’t get a soil probe into the ground to sample later. She is finding nematodes, nonetheless, and will sample later.

- Jeff Bradshaw- biological control strategies for management of western bean cutworm. Trichogramma wasps are haplodiploid and he has been mass rearing in NE. Trichogramma ostriniae- can they be brought from New York climate to NE? Low parasitism overall in both corn and dry bean. High fecundity, female-biased sex ratio, but not clear if there is any host preference or if the climate is ok. Can not yet achieve the desired 80% parasitism rate.

Special topics proposed for next year: sentinel plots; 2 ½ days of programming; side meetings or discussions virtually around special topics; survivorship, genotypes, and phenotypes of surviving larvae from seed blends; bring cotton-oriented person like Angus to discuss implications for Vip; abut joint meeting with S1080; more time for state reports; zoom meetings when EPA comes out with documents; industry liked open forums with them, rather than closed session by company; molecular markers for resistance monitoring; google docs table with update on relaxed research agreements to see where everyone else is on the process

International Presentation: Ostrinia and corn production in China– Kanglai He, Chinese Academy of Agricultural Sciences

- Overview of corn pests in China. Bt is not approved for release, but various events have been tested by scientists. Says block refuge wouldn’t work for small farmers. Natural refuge has worked for Bt cotton.

Accomplishments

Participants had 97 peer review publications and over 100 research reports and research & extension presentations that informed and educated stakeholders (producers, extension agents, and university and private sector scientists) of ongoing pest insect control issues in corn production.

Participants developed various extension videos on topics impacting corn pest insect control. This included videos describing Bt resistance development and grain crop management. Dozens of extension publications were produced or updated, including updates to managing Bt resistance, crop scouting guides, and those relating to western bean cutworm management and resistance to Bt toxins.

The Handy Bt Trait Table, available at www.texasinsects.org/bt-corn-trait-table.html, was updated to include observed field resistance among target pest species and corresponding citations in scientific literature. This designation was added to alert producers and consultants to potential management problems and to encourage field scouting.

Impacts

Obj. 1. Investigate the relationship between pest management technologies and the agricultural environment. • A description of how and when seed treatment insecticides move into aquatic systems provides direct data that can be used to estimate when aquatic environments (i.e. drainage ditches, creeks, watersheds as a whole) would be expected to receive highest concentrations of these insecticides. A lab study using a common aquatic macrophyte (duckweed) and an insect herbivore (duckweed aphid) clarified that clothianidin will move rapidly from water into this aquatic plant, but was not acutely toxic to the aphids at field concentrations during the study period. • Research under this objective is helping to improve our understanding of how insecticidal seed treatments may affect monarch butterflies. Insecticidal seed treatments, in particular neonicotinoids, are widely used in corn and can protect corn seeds and seedlings from early season pests. However, these insecticides also have the potential to harm non-target species such as the monarch butterflies, whose habitat is often in close proximity to agricultural fields. Understanding the potential risks to monarchs from these seed treatments will enable seed treatments to be used in the ways which minimize harm to the environment. • We are in the final year of three projects testing connections among conservation-based farming tactics, insecticide use, arthropod diversity and pest control in field crop production. In two separate, but related projects, we are studying connections between prophylactic insecticide use, soil health, and populations of insect and slug pests, weeds, and natural enemies. The hypothesis that we are testing is that annual inputs of preventative insecticides and fungicides will decrease soil quality and populations of predaceous arthropods and detritivores. One outcome that we have begun sharing with growers is that regular insecticide use (either seed treatments or pyrethroid sprays) retards decomposition by limiting collembolan populations. Fields with slower residue decomposition appear to have worse slug problems. We are encouraging farmers to use IPM rather than preventative insecticide use. • Use of neonicotinoid seed treatments in grain crop rotations. Impact statement: “Evaluating the ecological impacts of pesticide seed treatments on arthropod communities in a grain crop rotation,” pre-print available at https://www.biorxiv.org/content/10.1101/689463v1 and accepted in Journal of Applied Ecology determined that arthropod taxa can be impacted by neonicotinoid insecticides as well as seed treated fungicides, with impacts sometimes lasting for several months after planting. Neonicotinoids were not very persistent in the soil, and no economic benefits were observed for either the fungicide or insecticide components. These products should only be used where high early season pest pressure occurs. 2. At-planting soil pest control. Impact statement: An in-furrow pyrethroid or a neonicotinoid seed treatment (250 rate) were sufficient to mitigate moderate wireworm pressure and combining the two products did not improve yield. Given that neonicotinoid insecticides are included on virtually all corn seed, demonstrating that they are sufficient to control soil pests will prevent unnecessary in-furrow pyrethroid applications. 3. Tank mixing pyrethroids with herbicides and fungicides. Impact statement: Two year replicated strip trials indicate that foliar pyrethroids applied with post-emergence herbicides and at-tasseling fungicides provide no yield benefits in Maryland field corn. No pests were present at economic levels, though the 2019 herbicide timing significantly reduced the number of plant hoppers and plant bugs. Beneficials such as minute pirate bugs and lady beetles were common at both timings and pyrethroid applications did not significantly impact their abundance. This work will help growers avoid unnecessary applications of pyrethroid insecticides.
Obj. 2. Investigate the ecology, biology, evolution, genetics, and behavior of corn arthropods. • A review of the pest status, distribution and Bt resistance in the Western bean cutworm in the open-access Journal of IPM will allow pest managers, researchers, and industry personnel to have access to an updated description of this pest, and, in particular, avoid confusion regarding whether specific Bt traits are effective and where resistance has been documented. • The western corn rootworm is among the most serious pests of corn in North America. Costing US farmers over a billion dollars each year. Some of the most recent challenges posed by this pest include the evolution of resistance to transgenic Bt corn and conventional insecticides. Research under this objective generated new knowledge about how this insect moves within the agricultural landscape. Understanding the flight behavior of western corn rootworm will help to improve strategies to manage this pest and delay the development of resistance to current management practices. For example, this information will be used by those modeling Bt resistance development in western corn rootworm and developing resistance mitigation strategies, including scientists working for federal and state governments, universities, industry, and regulatory agencies. Other research on western corn rootworm under this objective includes the discovery of new DNA sequences for genes that are suspected of contributing to Bt resistance, and studies of naturally occurring insect killing fungi which may be used to suppress populations of western corn rootworm and reduce injury to corn. European corn borer is another key pest of corn in the United States. Interestingly, two strains of European corn borer that differ in the pheromone used in mate attraction coexist in the northeast United States, and these strain feed on different host plants. Research reported here has found that there is little genetic differentiation and high rates of gene flow between European corn borer pheromone strains, but strains remain diverged due to strong selection at a small number of genetic loci involved in mate attraction. Estimates of gene flow are important because they enable predictions concerning the spread of resistance alleles, and as such, these results are especially important now that European corn borer has evolve resistance to Bt corn in Nova Scotia, Canada, where these two pheromone strains also coexist. European corn borer population also differ in the number of generations per year (referred to as voltanism). In geographic regions where univoltine and multivoltine European corn borer are co-occur, the extent of mating period overlap may influence levels of gene flow. This research identified two genes involved in circadian rhythm that are the causal voltinism genes in European corn borer. These results are the first to identify the genes that determine voltinism, and will be crucial for future development of genetic markers to differentiate voltinism ecotypes and estimate levels of gene flow among field populations. Additionally, European corn borer populations have decreased substantially since the widespread adoption of hybrid corn producing Bacillus thuringiensis (Bt) toxins. Comparison of recent and historical light trap samples demonstrate a significant reduction in European corn borer captures, with a corresponding increase in proportion of suspected European corn borer that are actually the related species, the American lotus borer. Research conducted as part of this project provides a genetic marker that differentiates European corn borer and American lotus borer, and will be useful for determination of species and accurate European corn borer trap capture estimates. One common challenge when managing insect pest of corn is the development of insecticide resistance by these pests. Using the fruit fly, Drosophila melagaster, which is a model organism for the study of insects because of the detailed understanding of its genome, new knowledge has been generated about the mechanisms by which insects develop insecticide resistance. This change in knowledge will enable better strategies to be developed for managing insect pests in corn, in particular, strategies to delay the development of insecticide resistance, detect resistance once it arises, and mitigate the effects of insecticide resistance by reducing insect feeding injury to corn plants. • Transgenic corn, Zea mays L., hybrids expressing insecticidal Cry proteins from Bacillus thuringiensis (Bt) were evaluated in Florence, SC (with both early and late planting dates), and in Blackville, SC in 2019. Insect injury was limited to corn earworm (Helicoverpa zea) feeding in ears and yield was not affected by Bt traits. No ear injury to kernels was observed in an Optimum Leptra hybrid expressing Vip3A. Poor levels of control of ear injury were achieved in Genuity VT Double PRO (expressing Cry1A.105 and Cry2Ab2 for above ground pests), with 0% control in Blackville, 53% and 4% in Florence in early and late planted corn, respectively; this percent control compared to a non-Bt near isoline (average of 26% control across the three 2019 trials) reduced from 93-97% from 2011-2013 to 50-82% in 2014-2018 in trials in SC. The consistency of this reduction in efficacy is a concern, as work published in 2019 showed field colonies collected in the Carolinas tested against Cry1A.105 were highly resistant, with resistance ratios (RR) ranging from 13.5 to >4000. Against Cry2Ab2, 19 colonies were tested and RRs ranged from 0.26 to 33.7. Work continued in 2019 to determine the impact of Bt corn on the production of corn earworm pupae. This on-going work began in 2012, providing an overview of changes over time in susceptibility in corn earworm to Bt corn. Pupae were sampled by placing ears with late instar larvae in plastic boxes with soil to allow pupation. A total of 176 and 472 pupae were sampled in 2019 in early and late planted corn, respectively. Pupal weights were generally lower in Bt than in non-Bt corn. No pupa was collected from corn expressing Cry1F x Cry1Ab x Vip3A. The toxin Vip3A is the only Bt toxin that is currently providing excellent levels of control for corn earworm. • We now know how to efficiently collect NCR eggs from wild NCR and know the baseline susceptibility of an NCR laboratory colony to all Bt toxins. • Documentation of very low local WCR abundance as well as stable, albeit slightly-compromised, WCR susceptibility to the Cry34/35Ab1 toxin was presented to underscore the critical importance of maintaining (or adopting) an IPM-based approach to justify the use of Bt corn hybrids expressing Cry34/35Ab1, the only reliably efficacious Cry toxin expressed in Bt corn. A dramatic 2018-2019 increase in adoption of conventional, non-rootworm Bt corn hybrids, may be a response to well-publicized WCR abundance and Bt efficacy news; however, an historically wet planting season may have limited grower options/access to some Bt hybrids • Measuring gene flow between Bt and non-Bt plants. Impact statement: Cross-pollination between Bt field corn and structured refuge plants averaged 5.4% on adjacent rows and decreased significantly moving away from the interface. Outcrossing of pollen from the refuge plant in a seed blend averaged < 1% in neighboring Bt ears, but was much greater from Bt pollen in the opposite direction, averaging 18.6% in refuge ears. Diet bioassays incorporating kernel tissue from refuge plants in a 95:5% seed blend caused significant growth inhibition of H. zea and O. nubilalis larvae. • Identification of field-derived resistance mechanisms to Cry and Vip3A toxins in lepidopteran pests of corn and detection of their spread. Impact statement: Isolation and sequencing of genomic DNA from S. frugiperda individuals captured in locations in the continental US, Puerto Rico, Brazil and Kenya (Africa) allowed for genome-level comparisons. Results suggest lack of population structure and identify potential genomic regions associated with resistance. 2.Effects of transgenic corn on fall armyworm flight behavior. Impact statement: Flight propensity tests were performed by feeding S. frugiperda larvae from susceptible and Cry1F-resistant strains on control meridic diet or containing a sublethal concentration of Cry1Ac or Cry1Fa on the diet surface. The larvae fed ad libitum during the whole larval stage, and then the emerging adults after pupation were used for flight mill assays. Results detected increased flight of female armyworms when exposed to a sublethal (Cry1Ac) protein, and that this inducible effect becomes constitutive in Cry1F-resistant insects. • Texas conducted a replicate of Galen Dively's Sweet Corn Sentinel Plot trials to detect Bt resistance in corn earworm. There were 26 of these in the USA and Canada, and our replicate was by far the most geographically separated from the other replicates and had exceedingly high insect pressure • The mark/release/recapture techniques developed and validated in Tavares et al (2019) will facilitate pest dispersal research to be conducted with Noctuids, an economically damaging group of Lepidoptera.
Obj. 3. Develop and assess IPM and IRM systems for the arthropod complex in corn. • One aspect of integrated pest management (IPM) is the use of host-plant resistance, specifically, crop varieties that are better able to fend off insect pests and their associated yield losses. Research under this objective has led to the identification of new sources of native host-plant resistance in corn to fall armyworm, a challenging pest of corn that has developed resistance to several classes of insecticide including some Bt traits. Another serious lepidopteran (caterpillar) pest of corn is the corn earworm. Work has continued to elucidate the genetic and biochemical basis of a potentially novel host-plant resistance source against corn earworm. This host-plant resistance was discovered in silk tissue of Piura 208, a Peruvian landrace of corn (PI 503849). We have developed a quantitative corn earworm bioassay and tested it on four populations lines of corn that vary in their degree of resistance. This research will help to identify sources of host-plant resistance in corn to corn earworm, and decrease the yield losses imposed by this pest. Insect resistance management (IRM) is focused on delaying the development of resistance by insect pests to insecticides and transgenic insecticidal traits, in particular, transgenic traits that allow plants to produce insecticidal proteins derived from the bacterium Bacillus thuringiensis (Bt). Western corn rootworm is the most serious pest of corn in the US Corn Belt. Research under this objective has identified populations of western corn rootworm that are resistance to all commercially available Bt traits. Additionally, laboratory and field studies were conducted to provide a better understanding of what Bt resistance means in terms of injury to corn and yield loss. Knowledge of resistance by western corn rootworm to multiple Bt traits will enable farmers to reduce yield losses by changing their management approaches if they suspect resistance, and by using more diversified management approaches to delay additional cases of multi-trait Bt resistance. • A commercially-available artificial diet is available for western corn rootworm larvae that we developed. • A seed blend method has been used to provide susceptible insect populations for resistance management of Bt corn in the U.S. Corn Belt. One major concern for the use of seed blend is that larval movement of the target insect pests among non-Bt and Bt plants can affect the effectiveness of the refuge planting. Three caged-field trials were conducted in 2018 and 2019 to evaluate the larval survival and movement of the corn earworm (CEW), Helicoverpa zea, in eight seed blends of non-Bt and Bt corn containing Agrisure Viptera® corn expressing the Vip3A and Cry1Ab proteins. Each field plot consisted of five rows and 21 plants in each row with a structured refuge (100% non-Bt corn) and 0-30% seed blend non-Bt refuge. In each plot, 35 CEW neonates were infested on the ear silks of the center plant at the R1 plant stage. After 9-13 d of the neonate release, no live larvae or ear damages by CEW were observed from any Bt corn plants, regardless of the planting patterns. In the structured refuge or seed blends, CEW larvae demonstrated the capability to move from infested non-Bt ears to at least four plants away, as well as to the adjacent rows. However, majority of the larvae were found in the central row (66.8%), and the infested (34.5%) and adjacent (29.9%) plants. Overall, the number of live larvae recovered from the central non-Bt plants that were initially infested with CEW larvae in the three seed blends containing 10-30% non-Bt corn seeds was 27.5% less than that observed in the structured refuge planting. Across all treatments, ear damage area by CEW followed the similar patterns as the larval survival. Larvae recovered developed similarly among plantings and locations. The results suggest that, compared to structured refuge, seed bends could reduce refuge supply of CEW. Open-field and greenhouse trials were conducted during 2018-2019 to evaluate the performance of a Bt-susceptible and a dual-gene resistant heterozygous genotypes of fall armyworm (FAW), Spodoptera frugiperda, in six seed blends of pyramided Bt corn with 0-30% non-Bt refuge. In the pure non-Bt plantings, after 10-13 days of neonate releases on the vegetative stage plants, 0.39 and 0.65 larvae per plant with a leaf injury rating of 4.65 and 5.99 (Davis’s 1-9 scale) was recorded in the field and greenhouse trials, respectively. In contract, live larvae or plant injury were virtually not observed on Bt plants regardless of the planting patterns. In the field, larval occurrence and plant injury on non-Bt plants were similar between the seed blends and pure non-Bt plantings, suggesting that seed blends might be able to provide an equivalent refuge population as the structured refuge. In the greenhouse, the dual-gene heterozygous FAW in the seed blends also performed similarly as the Bt-susceptible larvae, indicating that the seed blends did not create more favorable conditions for the heterozygous-resistant insects. Recently, CEW has developed resistance to the two most common types of Bt proteins (Cry1 and Cry2) in plants targeting Lepidoptera. The Vip3A is a relatively new Bt protein that has incorporated into many corn and cotton varieties. Plants containing the Vip3A gene are effective against the Cry1/Cry2-resistant CEW and these Bt crop traits are expected to be planted widely in the near future. Thus, preservation of the Vip3A susceptibility is crucial for the sustainability of Bt crop technology. During 2017-2019, we conducted laboratory assays and F2 screen to 1) establish Vip3A baseline susceptibility of CEW in the U.S. southeast region, 2) determine the Vip3A resistance allele frequency, and 3) to assess the potential risk of resistance development in CEW to Vip3A. Diet overlay bioassays showed that all 27 field CEW populations collected from seven southeast states (LA, MS, AR, NC, SC, GA and FL) in 2018 and 2019 were susceptible to Vip3A. F2 screen didn’t find major resistance alleles to Vip3A in 93 family lines established from field collections in 2017-2019 and thus the resistance allele frequency with 95% probability was estimated to be < 0.0026 in the region. Laboratory-selected populations with up to 27-fold resistance couldn’t survive on Vip3A corn ears, suggesting that the corn plants containing the Vip3A gene produce a ‘high does’ against CEW. Information generated from this study will be useful for the proper use of Vip3A crop technology. Recently, field resistance of the corn earworm (CEW), Helicoverpa zea, to the Cry1A/Cry2A corn and cotton has been documented in some areas in the U.S. Cry1A.105 and Cry2Ab2 are the two Bt proteins expressed in a common Bt corn event, MON 89034. Both proteins target the above-ground lepidopteran pests including CEW. F2 screen was conducted to determine the Cry1A.105/Cry2Ab2 resistance allele frequency in CEW populations in the U.S. southeastern region and to establish Cry1A.105/Cry2Ab2-resistant CEW strains. The results showed that resistance allele frequencies in CEW in the region to both Cry1A.105 and Cry2Ab were very high, 0.31 with a 95% CI of 0.249-0.374 for Cry1A.105 and 0.29 with a 95% CI of 0.231 to 0.444. Resistance rates to Cry1A.105 and Cry2Ab2 were high after only a few generations of selections with the survivors in the F2 screen. The results suggest that resistance of CEW to Cry1A/Cry2 is common in the region. Data generated from this study should fill gaps in understanding single, dual-multiple-gene Bt resistance, as well as providing useful information for resistance monitoring, refining resistance modeling, improving resistance risk assessment, and developing management strategies for the sustainable use of pyramided Bt maize technology. Results from this project have been presented at several local, regional, national, and international meetings. At least four additional manuscripts will be generated from this project. One new student and two visiting scientists joined the project during 2019. • Monitoring resistance to Bt toxins. Impact statement: Sweet corn sentinel plots revealed that H. zea has lost most of its susceptibility to the Cry1Ab toxin. Moreover, larval densities in Bt ears reached levels higher than those in non-Bt ears, suggesting that a single gene Cry1Ab expressing plant could conceivably produce the same or even more moths emerging than from a refuge plant. Increases in the number and age of surviving larvae and kernel consumption in Cry1A.105+Cry2Ab2 sweet corn suggest that H. zea has become became more tolerant to these two toxins, even though the percent of ear damage has not significantly changed. The Cry1Ab+Vip3Aa sweet corn continues to provide high levels of field efficacy against H. zea, reducing the percent of damaged ears by 99% compared to the non-Bt isoline. However, three years of sentinel monitoring show a small but noticeable increase in the incidence of damage, and number and age of surviving larvae, suggesting a possible change in H. zea susceptibility in Vip3Aa trait. • Identification of new actives against fall armyworm. Impact statement: Seven day bioassays with neonate S. frugiperda from susceptible and Cry1F-resistant strains tested activity of plant leaf extracts, plant-derived chemicals, solubilized insecticidal proteins from Bacillus thuringiensis (Bt) isolates, and a chimeric protein combining domains of Cry1F and Cry2Aa proteins. Results support growth inhibitory effects of plant extracts and high activity of a Bt isolate from Sri Lanka. • Issue: Stink bugs have been an increasing problem in corn across the southeastern US. Approximately ten percent of the 880,000 corn acres in North Carolina were impacted by stink bugs during 2017, with an average yield loss of 30% on those acres. Based on 2017 average yields (142 bu/A), this represented a 3.7 million bushel loss. What has been done: Studies on insecticide efficacy, movement from other crops and wild hosts to corn, and the efficacy of aerial insecticide sprays were conducted. Furthermore, scouting procedures, previously based on whole plant samples, were re-evaluated during 2016 and 2017. We developed a sequential stop sampling plan using only certain parts of the plant from this research during 2018. These results were promoted at numerous grower meetings throughout the state and using the NCCE portal system during 2019. Impacts: These sampling recommendations were demonstrated to be very precise and will save scouts 59% more time when making a decision to treat. Furthermore, aerial applications of a pyrethroid over tasseling corn for stink bug were shown to be ineffective. A North Carolina farmer that grows approximately 20,000 acres of corn annually has stopped treating for stink bugs as a result of a collaborative study, saving $400,000 annually on this single farm. Issue: Stink bugs have been an increasing problem in soybeans across the US. Approximately 21% of the 1.7 million soybean acres in North Carolina were economically impacted by stink bugs during 2017 (with stink bugs present on 66% of the acres). Yield loss and costs of control topped $8 million for stink bugs in soybeans during 2017. • In conjunction with Cornell University, we applied entomopathogenic nematodes to 300 acres of a 500 acre continuous corn field in the northern panhandle for corn rootworm control. The success of small plot trials on this field in 2017 and 2018 caused the grower to want the whole field treated. We also applied entomopathogenic nematodes on two fields in New Mexico and demonstrated that center pivot application is a completely viable method. • Results from a collaboration with Corteva on corn earworm in seed corn production has impacted pest management recommendations for the 40,000 acres of Corteva seed corn production in Nebraska. By determining the functional resistance of corn earworm populations to multiple insecticides, using dose-response bioassays and simulated aerial applications, we developed recommendations for choice and rotation of active ingredients and application parameters (e.g., carrier volume) to maximize efficacy of insecticide applications. This will reduce the incidence of unnecessary and/or ineffective insecticide applications, and therefore reduce negative environmental and human health impacts. This is particularly important in seed corn production, as there is a low threshold for insect damage to the developing ears, as well as high potential for contact between de-tasseling field crews and insecticides. • provided print and web-based information for growers and crop consultants to assess and economically manage corn rootworms using a diverse set of management practices that slows the spread of Bt-resistance.
Obj. 4. Employ diverse delivery methods to disseminate information related to sustainable management of corn arthropod pests. • Over the past year, a wide variety of methods have been used to communicate information about insect pests of corn and their management, including online videos, peer-reviewed publication, presentations at scientific conference, book chapters and outreach publications. In particular, a book chapter published under this objective that provides a broad review of the application of host-plant resistance through genetic engineering within an context integrated pest management. Insect resistance management continues to be vital to ensuring the viability of transgenic technologies in agricultural crop plants, in particular corn. New approaches, such as RNAi and CRISPR, are considered. Anybody interested in insect-protected, genetically engineered crops will find this review useful. • In 2019, we published results of control evaluations for corn rootworm widely to our crop consultant and grower Extension clients in both print and electronic versions. This document was produced in collaboration with researchers in plant pathology as well as entomology, and provided an unbiased, third-party evaluation of insect and disease control methods. These reports were used to inform management decisions, allowing producers to choose effective control tactics where needed to optimize their economic returns. • Evaluating regional insect pest pressure. Impact statement: Sentinel untreated, non-Bt organic corn revealed inconsistent sporadic pest pressure that ranged from mild to moderate severity. One-size-fits-all preventative management technologies are not targeted for Maryland pests, and pest pressure does not justify preventative applications of insecticides, especially in Bt crops. • Expanding knowledge on damages caused by the sugarcane beetle an sporadic pest in corn • Extension Entomologists and IPM Agents produced approximately 35 newsletter articles detailing insect problems in corn in 2019. We also gave approximately 19 presentations on this topic. • Based on interactions with UNL extension, 89% of Nebraska Independent Crop Consultants Association members have changed their pest recommendations, impacting >0.25 million acres of Nebraska cropland. Examples of how their recommendations have changed include: “Have been more diligent in scouting for WBC,” “refined management of WBC treatments” and "best management practices for rootworm.” The seven presentations comprising the webinar "Corn rootworm management in the transgenic era" published online on the Plant Management Network during 2014 and 2015 have now collectively been viewed 22,428 times. All presenters were affiliated with U.S. land grant universities (most NC246 members). • Employed, radio, webinars, both formal and informal classroom and laboratory training, newsletter blogs, email and field days to provide information on corn arthropod diagnosis and management.

Publications

Obj. 1. Investigate the relationship between pest management technologies and the agricultural environment. 1a. Assess the need, efficacy and pest management window of seed treatment insecticides, primarily neonicotinoids, to control secondary below-ground insect pests. 1b. Evaluate possible effects of insecticidal seed coatings on non-target beneficial insects.

1. AM Alford and CH Krupke. 2019. Movement of the Neonicotinoid Seed Treatment Clothianidin into Groundwater, Aquatic Plants, and Insect Herbivores. Environmental science & technology 53 (24), 14368-14376

2. Walter, J. A., L. W. Sheppard, P. D. Venugopal, D. C. Reuman, G. Dively, J. F. Tooker, and D. M. Johnson. 2019. Weather and crop composition drive spatial synchrony of Lepidopteran agricultural pests. Ecological Entomology, in press. https://doi.org/10.1111/een.12830

3. Hiltpold, I. and B.E. Hibbard. 2018. Indirect root defenses cause induced fitness costs in Bt resistant western corn rootworm (Diabrotica virgifera virgifera LeConte). J. Econ. Entomol. 111: 2349-2358. (https://doi.org/10.1093/jee/toy220).

4. Pereira, A.E., T.A. Coudron, B.W. French, E.J. Bernklau, L.B. Bjostad, and B.E. Hibbard. 2019. Comparative susceptibility of western corn rootworm, Diabrotica virgifera virgifera LeConte neonates to selected insecticides and Bacillus thuringiensis proteins in the presence and absence of feeding stimulants. J. Econ. Entomol. 112: 842–851 (https://doi.org/10.1093/jee/toy415).

5. Dubey, A., M.T. Lewis, G.P. Dively, and K.A. Hamby. Accepted 2019, pre-print available at https://www.biorxiv.org/content/10.1101/689463v1. Evaluating the ecological impacts of pesticide seed treatments on arthropod communities in a grain crop rotation. Journal of Applied Ecology.

6. Dively, G.P., A.W. Leslie, and C.R.R. Hooks. 2020. Evaluating wildflowers for use in conservation grass buffers to augment natural enemies in neighboring cornfields. Ecological Engineering 144 (in press). https://doi.org/10.1016/j.ecoleng.2019.105703

7. Walter, J.A., L.W. Sheppard, P. D.Venugopal, D.C. Reuman, G.P. Dively, J.F. Tooker, and D.M. Johnson. 2019. Weather and regional crop composition variation drive spatial synchrony of lepidopteran agricultural pests. Ecological Entomology. https://doi.org/10.1111/een.12830.

8. Schaafsma, A.W., Limay-Rios, V., Baute, T., and Smith, J.L. 2019. Neonicotinoid residues in subsurface drainage and open ditch water around maize fields in southwestern Ontario. PLoS ONE. 14(4): e0214787. doi.org/10.1371/ journal.pone.0214787.

9. Editor-Reviewed Articles: DeVries, T.A., and R. J. Wright. 2019. Evaluation of seed-applied and liquid and granular insecticide formulations at planting for larval corn rootworm control, 2018. Arthropod Manag Tests 44. https://doi.org/10.1093/amt/tsz055

10. Mollet, K.A., G.E. Hirzel, C. Oliveira-Hofman and J.A. Peterson. 2019. Performance of seed treatments and in-furrow at-plant insecticides for protection against Cry3Bb1-resistant western corn rootworm, 2016. Arthropod Management Tests 44. https://doi.org/10.1093/amt/tsz002

11. Jones, M.S., J.A. Delborne, J. Elsensohn, P.D. Mitchell, and Z.S. Brown. 2019. Does the US public support using gene drives in agriculture? And what do they want to know? Science Advances 5(9):eaau8462 DOI: 10.1126/sciadv.aau8462

12. Chavas, J.P., and P.D. Mitchell. 2018. Corn Productivity: The Role of Management and Biotechnology. Corn, London: InTech. Online: https://www.intechopen.com/books/corn-production-and-human-health-in-changing-climate/corn-productivity-the-role-of-management-and-biotechnology.

Obj. 2. Investigate the ecology, biology, evolution, genetics, and behavior of corn arthropods. 2a. In cooperation with international community, develop genomics tools for key corn pests, including assembled and annotated genome and transcriptome sequences, genetic markers, and physical and QTL maps of important traits. 2b. Characterize races of corn pests, including ecology of races in sympatry. 2c. Assess effects of seed blend refuge in Bt corn on biology, development, and behavior of multiple lepidopteran pest species. 2d. Examine the potential role of microbial associates on important pest traits, including insecticide resistance, behaviors relevant to pest status, and insect-plant interactions. 2e. Characterize dispersal of adult WCR and lepidopteran pests, and assess its implications for IPM and for resistance development, spread, and mitigation.

13. Smith, J.S., C.D. DiFonzo, T.S. Baute, Michel, A.P., and C.H. Krupke. 2019. Ecology and management of the western bean cutworm (Lepidoptera: Noctuidae) in corn and dry beans - Revision with focus on the Great Lakes region. doi: 10.1093/jipm/pmz025.

14. JL Smith, CD Difonzo, TS Baute, AP Michel and CH Krupke. 2019. Ecology and Management of the Western Bean Cutworm (Lepidoptera: Noctuidae) in Corn and Dry Beans—Revision With Focus on the Great Lakes Region. Journal of Integrated Pest Management 10 (1), 27

15. Adedipe, F., Grubbs, N., Coates, B.S., Wiegmann, B., and Lorenzen, M. 2019. Structural and functional insights into the Diabrotica virgifera virgifera ATP-binding cassette (ABC) transporters gene family. BMC Genomics. 20(1): 899.

16. Coates, B.S., Kozak, G.M., Kim, K.S., Sun, J., Wang, Y., Fleischer, S., Dopman, E.B., and Sappington, T.W. 2019. Influence of host plant utilization and pheromone strain on variation between sympatric Ostrinia nubilalis populations. Mol Ecol 28(19): 4439-4452.

17. Coates, B.S., and Abel, C.A. 2019. Differentiation of European corn borer, Ostrinia nubilalis, and American lotus borer, O. penitalis, from North American field-collections. Journal of Economic Entomology 112(4): 2007-2011.

18. Kozak, G.M., Wadsworth, C.B., Kahne, S.C., Bogdanowicz, S.M., Harrison, R.G., Coates, B.S., and Dopman, E.B. 2019. Genomic basis of circannual rhythm in the European corn borer. Current Biology 29(20): 3501-3509.e5.

19. Seong, K.M., Coates, B.S., and Pittendrigh, B.R. 2019. Impacts of sub-lethal DDT exposures on microRNA and putative target transcript expression in DDT resistant and susceptible Drosophila melanogaster strains. Frontiers in Genetics 10: 45.

20. Seong, K.M., Coates, B.S., and Pittendrigh, B.R. 2019. Impacts of sub-lethal DDT exposures on microRNA and putative target transcript expression in DDT resistant and susceptible Drosophila melanogaster strains. Frontiers in Genetics 10: 45.

21. Steele, L.D., Coates, B.S., Seong, K.M., Valero, M.C., Mittapalli, O., Sun, W., Clark, J., and Pittendrigh, B.R. 2018. Changes in expression in mitochondrial pathways associated with DDT resistance in the 91-R strain of Drosophila melanogaster. Journal of Insect Science. 18(6): 1-11.

22. Yu, E. Y., A. J. Gassmann, and T. W. Sappington. 2019. Using flight mills to measure flight propensity and performance of western corn rootworm, Diabrotica virgifera virgifera (LeConte). Journal of Visualized Experiments 152: e59196, doi:10.3791/59196. URL: https://www.jove.com/video/59196

23. Yu, E. Y., A. J. Gassmann, and T. W. Sappington. 2019. Effects of larval density on dispersal and fecundity of western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae). PLoS ONE 14(3): e0212696.

24. Shelton, A. M., Romeis, J., Naranjo, S. E., Hellmich, R. L., Tian, J. C. 2016. Use of Bt-resistant caterpillars to assess the effect of Cry proteins on beneficial natural enemies. IOBC/WPSR Bulletin. 114:51-55.

25. Tian, J. C., Wang, X. P., Chen, Y., Romeis, J., Naranjo, S. E., Hellmich, R. L., Wang, P., and Shelton, A. M. Bt cotton producing Cry1Ac and Cry2Ab does not harm two parasitoids, Cotesia marginiventris and Copidosoma floridanum. Sci. Rep., 8(1), p.307. 2018

26. Reay-Jones, F.P.F. 2019. Pest status and management of corn earworm (Lepidoptera: Noctuidae) in field corn in the United States. Journal of Integrated Pest Management. 10(1): 1-9 (doi: 10.1093/jipm/pmz017).

27. Bilbo, T. R., F.P.F. Reay-Jones, D. D. Reisig, and J. K. Greene. 2019. Susceptibility of corn earworm (Lepidoptera: Noctuidae) to Cry1A.105 and Cry2Ab2 in North and South Carolina. Journal of Economic Entomology. 112: 1845-1857.

28. Bilbo, T. R., F.P.F. Reay-Jones, D. D. Reisig, J. K. Greene, and M. W. Turnbull. 2019. Development, survival, and feeding behavior of Helicoverpa zea (Lepidoptera: Noctuidae) relative to Bt protein concentrations in corn ear tissues. PLOS ONE. 14 (8): e0221343. https://doi.org/10.1371/journal.pone.0221343.

29. Caprio, M. A., R. Kurtz, A. Catchot, D. Kerns, D. Reisig, J. Gore, and F.P.F. Reay-Jones. 2019. The corn-cotton agroecosystem in the mid-southern United States: what insecticidal event pyramids should be used in each crop to extend Vip3A durability. Journal of Economic Entomology. 112: 2894-2906.

30. Bilbo, T. R., F.P.F. Reay-Jones, and J. K. Greene. 2020. Evaluation of insecticide thresholds in late-planted Bt and non-Bt corn for management of fall armyworm (Lepidoptera: Noctuidae). Journal of Economic Entomology. In press.

31. Rowen, E. K., J. F. Tooker, and C. Blubaugh. 2019. Soil fertility management to promote arthropod pest suppression. Invited manuscript, Biological Control 134: 130-140.

32. Rowen, E. K., and J. F. Tooker. 2019. Manure decreases herbivore performance but increases early-season damage on corn in the greenhouse and field. Environmental Entomology, in press. https://doi.org/10.1093/ee/nvz145

33. Mahmoud, M.A.B., R.E. Sharp, M.J. Oliver, D.L. Finke, M. Bohn, M.R. Ellersieck, and B.E. Hibbard. 2018. Interactive effects of western corn rootworm and drought on Maize hybrids with and without drought- and rootworm-tolerance in the field. J. Econ. Entomol. 111: 193–208 (https://doi.org/10.1093/jee/tox309).

34. Bohn, M.O., J.J. Marroquin, S. Flint-Garcia, K. Dashiell, D.B.Willmot, and B.E. Hibbard. 2018. QTL mapping of western corn rootworm (Coleoptera: Chrysomelidae) host plant resistance in two populations of doubled haploid lines in maize (Zea mays L.). J. Econ. Entomol. 111:435–444 (https://doi.org/10.1093/jee/tox310).

35. Geisert, R.W., D.J. Cheruiyot, B.E. Hibbard, D.I. Shapiro-Ilan, K.S. Shelby, T.A. Coudron. 2018. Comparative assessment of four Steinernematidae and three Heterorhabditidae species for infectivity of larval Diabrotica virgifera virgifera. J. Econ. Entomol. 111: 542–548. (https://doi.org/10.1093/jee/tox372).

36. Bernklau, E. J., B. E. Hibbard, and L. B. Bjostad. 2018. Sugar preferences of western corn rootworm larvae in a feeding stimulant blend. J. Appl. Entomol. 142: 947-958 (https://onlinelibrary.wiley.com/doi/epdf/10.1111/jen.12540).

37. Jaffuel, G., N. Imperiali, K. Shelby, R. Campos-Herrera1, R. Geisert, M. Maurhofer, J. Loper, C. Keel, T.C.J. Turlings, and B. E. Hibbard. 2019. Protecting maize from rootworm damage with the combined application of arbuscular mycorrhizal fungi, Pseudomonas bacteria and entomopathogenic nematodes. Sci. Reports 9:3127 | https://doi.org/10.1038/s41598-019-39753-7.

38. Bernklau, E.J., B.E. Hibbard, and L.B. Bjostad. 2019. Repellent effects of methyl anthranilate on western corn rootworm larvae in soil bioassays. J. Econ. Entomol. 112: 683 – 690 (https://doi.org/10.1093/jee/toy346).

39. Geisert, R.W., D.C. Ludwick, and B.E. Hibbard. 2019. Effects of cold storage on non-diapausing eggs of the western corn rootworm (Diabrotica virgifera virgifera). J. Econ. Entomol. 112: 708 – 711 (https://doi.org/10.1093/jee/toy405).

40. Zhao, Z., L.N. Meihls, B.E. Hibbard, C. G. Elsik, T. Ji, and K.S. Shelby. 2019. Differential gene expression in response to eCry3.1Ab ingestion in an unselected and eCry3.1Ab-selected western corn rootworm (Diabrotica virgifera virgifera LeConte) population. Scientific Reports | 9:4896 | https://doi.org/10.1038/s41598-019-41067-7.

41. Ludwick, D.C., A.C. Ericson, L.N. Meihls, M.L. Gregory, T.A. Coudron, B.E. Hibbard, and K.S. Shelby. 2019. Survey of microbes associated with all western corn rootworm life stages reveals no difference between insects reared on different soils. Scientific Reports | 9:15332 (https://www.nature.com/articles/s41598-019-51870-x).

42. Zhang, X., C. van Doan, C.C.M. Arce, L. Hu, S. Gruenig, B.E. Hibbard, M.R. Hervé, C. Nielson, C.A.M. Robert, R.A.R. Machado, and M. Erb. 2019. Plant defense resistance in natural enemies of a specialist insect herbivore. PNAS 116: 23174–23181. (https://www.pnas.org/content/early/2019/10/25/1912599116).

43. Pereira, A.E., D.C. Ludwick, J. Barry, L.J. Meinke, D.J. Moellenbeck, K. Hyte, A. Ernwall, K. Paddock, and B.E. Hibbard. 2019. Optimizing egg recovery from wild northern corn rootworm beetles. J. Econ. Entomol. 112: 2737–2743. (https://doi.org/10.1093/jee/toz234).

44. Dively, G.P., F. Huang, I. Oyediran, T. Burd, and S. Morsello. 2019. Evaluation of gene flow in structured and seed blend refuge systems of non-Bt and Bt corn. J. of Pest Sci. doi:10.1007/s10340-019-01126-4

45. Smith, J.L., C.D. DiFonzo, T.S. Baute, A.P. Michel, and C.H. Krupke. 2019. Ecology and management of the western bean cutworm (Lepidoptera: Noctuidae) in corn and dry beans – Revision with focus on the Great Lakes region. JIPM. 10(1): 27. doi.org/10.1093/jipm/pmz025.

46. Tavares, C.S., Paula-Moraes, S.V., Valencia-Jimenez, A., Hunt, T.E., Vélez, A.M., Pereira, E.J.G. 2019. Egg albumin as a protein marker to study dispersal of Noctuidae in the agroecosystem. Environmental Entomology, 48:1260-1269. https://doi.org/10.1093/ee/nvz118.

47. Montezano, D.G., Specht, A., Sosa-Gómez, D.R., Roque-Specht, V.F., Paula-Moraes, S.V., Peterson, J.A., Hunt, T.E. 2019. Developmental parameters of Spodoptera frugiperda (Lepidoptera: Noctuidae) immature stages under controlled and standardized conditions. Journal of Agricultural Science, 11:76-89.

48. Montezano, D.G., Specht, A., Sosa-Gómez, D.R., Roque-Specht, V.F., Malaquias, J.V., Paula-Moraes, S.V., Peterson, J.A., Hunt, T.E. 2019.Biotic potential and reproductive parameters of Spodoptera frugiperda (JE Smith, 1797)(Lepidoptera: Noctuidae). Journal of Agricultural Science, 11:240-252.

49. Pannuti, L.E.R., Baldin, E.L.L.L, Paula-Moraes, S.V., Hunt, T.E., Canassa, V.F., Bentivenha, J.P.F., Silva, I.F. 2019. External marking and behavior of early instar Helicoverpa armigera (Lepidoptera: Noctuidae) on soybean. Florida Entomologist, 102: 90-95.

50. Kaur, G., Guo, J., Brown, S., Head, G.P., Price, P.A., Paula-Moraes, S., Ni, X., Dimase, M., Huang, F. 2019. Field-evolved resistance of Helicoverpa zea (Boddie) to transgenic in northeast Lousiana, the United States. Journal of invertebrate pathology, 163: 11-20.

51. Babu, A., D. Reisig, J. Walgenbach, R. Heiniger, and W. Everman. 2019. Influence of weed manipulation in field borders on brown stink bug (Hemiptera: Pentatomidae) densities and damage in field corn. Environ. Entomol. 48: 434-443. doi: 10.1093/ee/nvz016

52. Yang, F., J. Williams, P. Porter, F. Huang and D.L. Kerns. 2019. F2 screen for resistance to Bacillus thuringiensis Vip3Aa51 protein in field populations of Spodoptera frugiperda (Lepidoptera: Noctuidae) from Texas, USA. Crop Protection 126: 104915.

53. Montezano, D.G., T.E. Hunt, A. Specht, P.M. Colombo da Luz and J.A. Peterson. 2019d. Survival and development of Striacosta albicosta (Smith) (Lepidoptera: Noctuidae) immature stages on dry beans, non-Bt, Cry1F and Vip3A maize. Insects 10: 343. https://doi.org/10.3390/insects10100343

54. Montezano, D.G., T.E. Hunt, A. Specht, P.M. Colombo da Luz and J.A. Peterson. 2019c. Life cycle parameters of Striacosta albicosta (Smith) (Lepidoptera: Noctuidae) under laboratory conditions. Journal of Insect Science 19: 14; 1-8. https://doi.org/10.1093/jisesa/iez073

55. Montezano, D.G., A. Specht, D.R. Sosa-Gómez, V.F. Roque-Specht, J.V. Malaquias, S.V. Paula-Moraes, J.A. Peterson and T.E. Hunt. 2019b. Biotic potential and reproductive parameters of Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae). Journal of Agricultural Science 11: 240-252. https://doi.org/10.5539/jas.v11n13p240

56. Montezano, D.G., A. Specht, D.R. Sosa-Gómez, V. Ferreira Roque-Specht, S.V. Paula-Moraes, J.A. Peterson and T.E. Hunt. 2019a. Developmental parameters of Spodoptera frugiperda (Lepidoptera: Noctuidae) immature stages under controlled and standardized conditions. Journal of Agricultural Science 11: 76-89. https://doi.org/10.5539/jas.v11n8p76

57. Pereira, A.E., B. Tenhumberg, L.J. Meinke, B.D. Siegfried. 2019. Southern corn rootworm (Coleoptera: Chrysomeldiae) adult emergence and population growth assessment after selection with vacuolar ATPase-A double-stranded RNA over multiple generations. J. Econ. Entomol. 112: 1354-1364. doi: 10.1093/jee/toz008

58. Pereira, A.E., D.C. Ludwick, J. Barry, L.J. Meinke, D.J. Moellenbeck, K. Hyte, A. Ernwall, K. Paddock, and B.E. Hibbard. 2019. Optimizing egg recovery from wild northern corn rootworm beetles. J. Econ. Entomol. 112: 2737–2743. doi.org/10.1093/jee/toz234.

59. Schuster N.R., J.A. Peterson, J.E. Gilley, L.R. Schott & A.M. Schmidt. 2019. Soil arthropod abundance and diversity following land application of swine slurry. Agricultural Sciences 10: 150-163. https://doi.org/10.4236/as.2019.102013

60. Tavares, C.S., S. V. Paula-Moraes, A. Valencia-Jimenez, T. E. Hunt, A. M. Vélez, E.J.G. Pereira. 2019. Egg albumin as a protein marker to study dispersal of Noctuidae in the agroecosystem. Environ. Entomol. 48(6):1260-1269, doi: 10.1093/ee/nvz118

61. Vélez A.M., E. Fishilevich, M. Rangasamy, C. Khajuria, D.G. McCaskill, A.E. Pereira, P. Gandra, M.L. Frey, S.E. Worden, S.L. Whitlock, W. Lo, J.R. Lutz, K.E. Narva, and B.D. Siegfried. 2019. Control of western corn rootworm via RNAi traits in maize: lethal and sublethal effects of Sec23 dsRNA. Pest Management Science. DOI 10.1002/ps.5666.

Obj. 3. Develop and assess IPM and IRM systems for the arthropod complex in corn. 3a. Characterize and monitor for resistance of lepidopteran pests to Bt corn and conventional insecticides, and assess possible IRM and mitigation strategies. 3b. Characterize geographic extent and nature of resistance of Diabrotica spp. to Cry toxins, pyrethroids, and other insecticides, and develop appropriate IPM and IRM strategies for problem areas. 3c. Work toward improving an artificial diet for WCR rearing and more sensitive bioassays of toxins. 3d. Develop strategies to manage the ear-feeding pest complex and model implications for IRM and IPM. 3e. Develop Helicoverpa armigera early detection and mitigation network. 3f. Develop region-specific bioeconomic models to assess refuge and IPM strategies for managing lepidopteran and coleopteran pest resistance to Bt corn expressing stacked and pyramided toxins. 3g. Assess the extent to which limited farmer access to Bt corn varieties targeting only coleopteran or only lepidopteran pests affects the risk of resistance when the economic importance of each pest varies regionally.

62. Gutiérrez-Moreno, R., D. Mota-Sanchez, C. A. Blanco, M. E. Whalon, H. Terán Santofimio, J. C. Rodriguez-Maciel, and C.D. DiFonzo. 2018. Field-evolved resistance of the fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae) to conventional insecticides in Mexico and Puerto Rico. J. Econ. Ent. https://doi.org/10.1093/jee/toy372

63. Abel, C. A., Coates, B. S. and Scott, M. P. 2019. Evaluation of maize germplasm from Saint Croix for resistance to leaf feeding by fall armyworm. Southwestern Entomologist. 44:99-103.

64. Lopez, M. D., Dennison, T. S., Paque, T. M., Yandeau-Nelson, M. D., Abel, C. A. and Lauter, N. 2019. Development and application of a quantitative bioassay to evaluate maize silk resistance to corn earworm herbivory among progenies derived from Peruvian landrace Piura. PLoS ONE. 14(4): e0215414. https://doi.org/10.1371/journal.pone.0215414

65. Gassmann, A. J., Shrestha, R. B., Kropf, A. L., St. Clair, C. R. and Brenizer, B. D. 2020. Field-evolved resistance by western corn rootworm to Cry34/35Ab1 and other Bacillus thuringiensis traits in transgenic maize. Pest Management Science 76:268-276

66. Shrestha, R. B. and Gassmann, A. J. 2019. Field and laboratory studies of resistance to Bt corn by western corn rootworm (Coleoptera: Chrysomelidae). Journal of Economic Entomology 112:2324-2334

67. Ludwick, D.C., L.N. Meihls, M.P. Huynh, A.E. Pereira, B.W. French, T.A. Coudron, and B.E. Hibbard. 2018. A new artificial diet for western corn rootworm larvae is compatible with and detects resistance to all current Bt toxins. Scientific Reports: 8:5379 | (https://doi.org/10.1038/s41598-018-23738-z).

68. Meihls, L.N., M.P. Huynh, D.C. Ludwick, T.A. Coudron, B.W. French, K. Shelby, A.J. Hitchon, A.W. Schaafsma, A.E. Pereira, and B.E. Hibbard. 2018. Comparison of six artificial diets for support of western corn rootworm bioassays and rearing. J. Econ. Entomol. 111: 2727-2733 (https://doi.org/10.1093/jee/toy268).

69. Huynh, M.P., B.E. Hibbard, S.L. Lapointe, R.P. Niedz, B.W. French, A.E. Pereira, D.L. Finke, K.S. Shelby, and T.A. Coudron. 2019. Multidimensional approach to formulating a specialized diet for northern corn rootworm larvae. Scientific Reports: 9:3709 | https://doi.org/10.1038/s41598-019-39709-x

70. Huynh, M.P., E.J. Bernklau, T.A. Coudron, K.S. Shelby, L.B. Bjostad, and B.E. Hibbard. 2019. Characterization of corn root factors to improve artificial diet for western corn rootworm larvae. J. Insect Sci. 9: 19; 1–8 (https://doi.org/10.1093/jisesa/iez030).

71. Huynh, M.P., B.E. Hibbard, M. Vella, S.L. Lapointe, R.P. Niedz, K.S. Shelby, and T.A. Coudron. 2019. Development of an improved and accessible diet for western corn rootworm larvae using response surface modeling. Scientific Reports | 9:16009 (https://www.nature.com/articles/s41598-019-52484-z).

72. Niu, Y., J. Guo, G.P. Head, P.A. Price and F. Huang. 2019. Phenotypic performance of nine genotypes of Cry1A.105/Cry2Ab2-dual gene resistant fall armyworm on non-Bt and MON 89034 maize. Pest Manag. Sci. 75:2124-2132.

73. Kaur, G., J. Guo, S. Brown, G.P. Head, P.A. Price, S. Paula-Moraes, X. Ni, M. Dimase and F. Huang. 2019. Field-evolved resistance of Helicoverpa zea (Boddie) to transgenic maize expressing pyramided Cry1A.105/Cry2Ab2 proteins in northeast Louisiana, the United States. J. Invertebr. Pathol. 163: 11-20.

74. Chen, X., G.P. Head, D.L. Kerns, P. Price, M.E. Rice, F. Huang, R.T. Gilreath, and F. Yang. 2019. Fitness costs of Vip3A resistance in Spodoptera frugiperda on different hosts. Pest Manage. Sci. 75: 1074-1080.

75. Zhu, C., Y. Niu, Y. Zhou, J. Guo, G.P. Head, P.A. Price, X. Wen, and F. Huang. 2019. Survival and effective dominance level of a Cry1A.105/Cry2Ab2-dual gene resistant population of Spodoptera frugiperda (J.E. Smith) on common pyramided Bt corn traits. Crop Protect. 115: 84-91.

76. Baragamaarachchi, R.Y., Samarasekera, J.K.R.R., Weerasena, O.V.D.S.J., Lamour, K., and J. L. Jurat-Fuentes. 2019. Identification of a native Bacillus thuringiensis strain from Sri Lanka active against Dipel-resistant Plutella xylostella. PeerJ 7: e7535

77. Smith, J.L., Y. Farhan, and A.W. Schaafsma. 2019. Practical resistance of Ostrinia nubilalis (Lepidoptera: Crambidae) to Cry1F Bacillus thuringiensis maize discovered in Nova Scotia, Canada. Scientific Reports 9 (1): 18247. doi:10.1038/s41598-019-54263-2.

78. Farhan, Y., Smith, J.L., and A.W. Schaafsma. 2019. Susceptibility of different instars of Striacosta albicosta (Lepidoptera: Noctuidae) to Vip3A, a Bacillus thuringiensis protein. J Econ Ent. doi.org/10.1093/jee/toz118.

1. Caprio, M., K. Ryan, A. Catchot, D. Kerns, D. Reisig, J. Gore, F. Reay-Jones. 2019. The corn-cotton agroecosystem in the mid-southern United States: what insecticidal event pyramids should be used in each crop to extend Vip3A durability. J. Econ. Entomol. 112: 2894-2906. doi: 10.1093/jee/toz208 2.

2. Bilbo, T. F.P.F. Reay-Jones, D. D. Reisig, J. K. Greene, and M. W. Turnbull. 2019. Development, survival, and feeding behavior of Helicoverpa zea (Lepidoptera: Noctuidae) relative to Bt protein concentrations in corn ear tissues. PLoS ONE doi: 10.1371/journal.pone.0221343 3.

3. Bilbo, T., F. Reay-Jones, D. Reisig, and J. Greene. 2019. Susceptibility of corn earworm (Lepidoptera: Noctuidae) to Cry1A.105 and Cry2Ab2 in North and South Carolina. J. Econ. Entomol. 112: 1845-1857. doi: 10.1093/jee/toz062

79. Carmona, G., J. Rees, R. Seymour, R. Wright, and A. J. McMechan. 2019. Wheat Stem Maggot (Diptera: Chloropidae): An emerging pest of cover crop to corn transition systems. Plant Health Progress. 20: 147-154.

80. Christiaens, O., S.Whyard, A.M. Vélez, G. Smagghe. 2019. RNA Interference technologies to control insect pests: current status and challenges. Frontiers in Plant Science. In Press.

81. Montezano, D.G., T.E. Hunt, D. Souza, B.C. Vieira, A.M. Vélez, G.R. Kruger, S.N. Zukoff, J.D. Bradshaw and J.A. Peterson. 2019e. Bifenthrin baseline susceptibility and evaluation of simulated aerial applications in Striacosta albicosta (Smith) (Lepidoptera: Noctuidae). Journal of Economic Entomology 112: 2915-2922. https://doi.org/10.1093/jee/toz237

82. Naranjo S., R. Hellmich, J. Romeis, A. Shelton, and A.M. Vélez. 2020. The Role and Use of Genetically Engineered Insect-Resistant Crops in IPM Systems. In: Integrated Pest Management of Insect Pests: Current and Future Developments. Burleigh Dodds Science Publishing. Marcos Kogan and Elvis ‘Short’ Heinrichs eds. Burleigh Dodds Science Publishing, Cambridge, UK.

83. Silva, P.R. da, A.N. Istchuk, T.E. Hunt, C.S. Bastos, J.B. Torres, K.L. Campos and J. Foresti. 2019. Susceptibility of corn to stink bug (Dichelops melacanthus) and its management through seed treatment. Australian Journal of Crop Science 13(12):2015-2021, doi: 10.21475/ajcs.19.13.12.p2021

84. Souza, D., B. C. Vieira, B. K. Fritz, W.C. Hoffmann, J. A. Peterson, G. R. Kruger, L. J. Meinke. 2019. Western corn rootworm pyrethroid resistance confirmed by aerial application simulations of commercial insecticides. Sci. Rpts. 9:6713. doi.org/10.1038/s41598-019-43202-w

85. Souza, D., J.A. Peterson, R.J. Wright, L.J. Meinke. 2019. Field efficacy of soil insecticides on pyrethroid-resistant western corn rootworms (Diabrotica virgifera virgifera LeConte). Pest Manag. Sci. published online Sept. 2019: doi: 10.1002/ps.5586

86. Editor-Reviewed Articles: DeVries, T.A., R. J. Wright. 2019. Evaluation of granular insecticide formulations of tefluthrin at planting for larval corn rootworm control, 2018. Arthropod Manag Tests 44. https://doi.org/10.1093/amt/tsz041

87. DeVries, T.A., R. J. Wright. 2019. Evaluation of traited corn rootworm and refuge corn hybrids in combination with soil insecticides at planting for larval corn rootworm control, 2018. Arthropod Manag Tests 44. https://doi.org/10.1093/amt/tsz054

88. DeVries, T.A., R. J. Wright. 2019.Evaluation of liquid and granular insecticide formulations at planting for larval corn rootworm control, 2018A. Arthropod Manag Tests 44. https://doi.org/10.1093/amt/tsz056

89. DeVries, T.A., R. J. Wright. 2019.Evaluation of liquid and granular insecticide formulations at planting for larval corn rootworm control, 2018B. Arthropod Manag Tests, 44. https://doi.org/10.1093/amt/tsz057

90. Swoboda-Bhattarai, K.A., S.R. Daniel and J.A. Peterson. 2019b. Evaluation of foliar insecticide application timing for the control of western bean cutworm in field corn, 2018. Arthropod Management Tests 44. https://doi.org/10.1093/amt/tsz090

91. Swoboda-Bhattarai, K.A., S.R. Daniel and J.A. Peterson. 2019a. Evaluation of foliar insecticides for the control of western. bean cutworm in field corn, 2018. Arthropod Management Tests 44. https://doi.org/10.1093/amt/tsz063

Obj. 4. Employ diverse delivery methods to disseminate information related to sustainable management of corn arthropod pests. 4a. Establish an NC-205 video library website with permanent high quality versions of IPM videos for open online access and download to computer and portable electronic devices. 4b. Produce and deploy a comprehensive IPM system for cost-effective prevention, early detection, rapid diagnosis, and mitigation of new and emerging corn pests that links all stakeholders who have common interests in pest detection and management. 4c. Develop an array of IPM and IRM distance education workshops.

92. Naranjo, S. E., Hellmich, R. L., Romeis, J., Shelton, A. M., and Vélez, A. M. The role and use of genetically engineered insect-resistant crops in IPM systems, pp. 283–340. In M. Kogan and E. Heinrichs (eds.), Integrated management of insect pests: current and future developments. Burleigh Dodds Science Publishing, Cambridge, UK. 2020.

93. De Bortoli, C.P., and J.L. Jurat-Fuentes. 2019. Mechanisms of resistance to commercially relevant entomopathogenic bacteria. Curr Opin Insect Sci 33:56-62

94. Extension Publications (examples): Bradshaw, J. 2019. What’s New in Entomology: Nebraska Panhandle, Crop Production Clinic Proceedings. https://cropwatch.unl.edu/2019/what%E2%80%99s-new-entomology-nebraska-panhandle Hunt T., J. Peterson, A. Vélez and R. Wright. May 22, 2019. First European Corn Borer Resistance to Bt Corn Reported in Canada. Nebraska Extension CropWatch.

95. Peterson J., K. Swoboda Bhattarai, J. Cluever, J. McMechan and J. Bradshaw. June 21, 2019. Using Degree-Day Models to Predict Western Bean Cutworm Flights. Nebraska Extension CropWatch.

96. Swoboda Bhattarai K., J. Peterson and T. Hunt. 2019. The Biology and Management of Ear-Feeding Lepidopteran Pests of Corn in Nebraska. Nebraska Extension Crop Production Clinic Proceedings.

97. Swoboda Bhattarai K., J. Peterson and S. Daniel. March 8, 2019. Introducing the ‘Western Bean Cutworm Central’ Webpage. Nebraska Extension CropWatch.

Back