Brief Summary of Minutes of Annual Meeting

Monday, January 26, 2009 Elson Shields welcomed everyone to the meeting and mentioned that the agenda should be in everyones hands. He commented about the external meeting on Tuesday night with industry folks from Dow and then Pioneer. Dave Andow discussed the local arrangements for the meeting. He welcomed us to Minnesota. He first talked about the projection system set up. The meetings on Tuesday night will be at the University. He brought up the idea of an organized dinner for Monday, which most of the group supported. Registration fee for this meeting will be $100. If staying for the joint meeting, the cost will be $150. If staying over for the NC205 meeting, the cost will be $200. Continental breakfast will be provided each morning in the meeting room. Elson then asked for everyone to introduce themselves. Steve Pueppke gave an administrative update. NCCC46 is going through a mid term review. Next year the group should be getting involved in the rewrite of the committee. He mentioned that this is the year of a new farm bill which includes some major reorganization of the groups that support groups such as ours and the NRI program. A lot of money will be going towards competitive funds rather than formula funding. There is a push to bring agricultural research up to the same level as NSF or medical funding. Steve asked if there were any questions. Elson brought up the minutes from last year, and asked for approval of them. They were approved unanimously. A nomination committee was selected. The group was Joe Spencer and Mark Boetel. The group will need to identify a new secretary for 2010. Ken Ostlie was thanked for his willingness to step in as the new chair. Elson than asked for members to be a site selection committee. Pat Porter and Eileen Cullen volunteered. Both Madison, WI, and Columbus, OH, were discussed. Future meeting format and meeting with NC205. The committee should discuss over the next few days and it will be brought up later during the meeting. Management Guide for Corn Rootworms.  Joe Spencer discussed the current status of it. The guide is at the point where they have passed it along to a publication office. Ken Ostlie thanked all those who provided photos for the guide. There are still some photos that are missing. Ken discussed what will happen in the near future with final approval. Ken hopes to have a finished copy around the NC Branch meeting. He then discussed the various ideas for circulating the guide, and what to do with any funds brought in from its sale. Jon Tollefson discussed Marlin Rice leaving ISU within the next few weeks for a job with Pioneer. Lance Meinke mentioned that Gary Hein will be leaving the western NE location and moving to Lincoln for a new position. His old job is opening up for a replacement. State Reports Bruce Hibbard said that he had a CD of state reports. He sent copies around for people. Distribution, abundance, and species composition IL  Joe Spencer said they had high adoption of transgenic corn. He observes that there seems to be a general decline of rootworms across the state. IN  Larry Bledsoe said they have seen a general decline also, although he does not think its necessarily related to the amount of transgenic corn. He thinks there are a lot of environmental conditions that might be causing it. He saw a generally late population this past summer. IA  Jon Tollefson said that the variant is in generally in the east side of IA by Dubuque and around the Quad Cities. Tom Sappington discussed the expansion of the WCR across the country and in Europe and pointed out two new reviews: Gray et al. 2009 Annu. Rev. Entomol. 54: 303-321; Meinke et al. 2009 Agric. For. Entomol. 11: 29-46. Both have thorough discussions of history and dynamics of the expansions, and Gray et al. also has several good maps. KS  Brian McCornack said that populations were low this year. MI  Chris Difonzo said they were low, with variants in a localized area in central MI. MN  Ken Ostlie also saw lower numbers, with a shift in some places towards northerns. They discussed some of the relationships between westerns and northerns in the state. MO  Bruce Hibbard discussed the situation in the state, without any specific comments on populations. NE  Lance Meinke talked about the wet and cold weather, and the subsequent lower numbers. Western NE had some higher numbers. Northerns are still high in northeast Nebraska. NY  Elson Shields said that there was little economic damage in the state. ND  Mark Boetel stated that NCR has been the predominant species observed in informal surveys in ND during the past few years. . Populations are concentrated in the southeastern portion of the state. OH  Ron Hammond and Bruce Eisley said that the variant has gone farther south and east into Ohio, below I-70 and into central OH north of Columbus towards the north. PA  John Tooker said they were generally low. SD - Brad McManus said that dry areas were higher with wet areas low, with a lot of northerns being observed. TX  Pat Porter said that Mexican corn rootworms were general low, although southern corn rootworm appeared in some places. WI  Eileen Cullen said that the two species are about 60:40 WCR:NCR in state. CRW pressure in UW Madison efficacy trials is heavy each year because we trap crop the field sites (plant corn late June of previous year to have pollen/silks to attract egg-laying adults). CRW pressure in commercial fields (continuous, normal May corn planting dates) varies from year to year. CRW damage reported each year. Increasing attention to CRW damage in corn silage growing areas in eastern WI. WI Association of Production Ag Consultants reported to Cullen lack of efficacy on CRW trait (Agrisure, and anecdotally other brands). Some consultants and growers are adding soil insecticide to transgenic corn, especially those from Agrisure. They also saw lower pressure of the variant western corn rootworm this past year in Wisconsin. No trapped fields in the WI Dept. of Agriculture pest survey reached threshold, all soybean fields trapped with 12 Pherocon yellow sticky traps were far below 5 beetles/trap/day economic threshold (i.e. below 1 b/t/d). She shared with the group various extension publications they produced. Ontario  Tracey Baute reported they were normal or maybe even slightly higher in terms of general pressure, and that Poncho 1250 did not work well. The variant is not that high generally in the province yet except for one location or pocket. Behavior and Ecology IL  Oviposition studies were conducted with beheaded beetles. Beheaded females generally oviposited eggs rapidly. 32% of beheaded females had ruptured oviducts. Discussed some of their observations of mating for insects from transgenic and refuge corn. Numerous committee members joined in a discussion of what has been seen by others on mating- and dispersal-related issues. MN  looking at volunteer corn issues, which will be discussed under management. NE  looking at differences between two different species barberi and longicornis knowing that they have a good overlap in their range. They were doing this especially with mating behavior. SD  mating behavior studies are finishing. Brain McCormick asked if there are some basic behaviorally or ecological items that are not being addressed that should be. Tom mentioned long range dispersal as an area of interest. Ron Hammond mentioned that OSU has a new person, Mary Gardiner, who is a landscape ecologist who wants to work with specific pests and how it can impact management of those pests. BREAK Biology IL  Has observed some color differences of WCR. A melanic color variation is about 1% of the population. In Europe, its a lot higher. Genetic studies have been initiated. Also are conducting some studies and beginning to consider what might happen if additional host plants of rootworms are grown for biomass for biofuel uses. He is specifically working with Miscanthus gigantueus. IA . Aaron (IS) is beginning studies with various colonies of the different species and types. Sappington discussed aspects of population genetics and potential long range dispersal. There was an active discussion on various aspects of this area. The findings so far suggest WCR across the U.S. are similar genetically speaking. He also discussed some work they have done in Europe with the WCR. They have been able to conclude that there were five independent introductions in Europe. He passed out information on a recent WCR genome sequencing workshop that was held in Reno, NV, and what was discussed. MO  Discussed some of the publications forthcoming and over the past year on research of the biology of rootworms. NE  Attempting to better examine extended diapause of NCR. SD  Discussed some studies with mating of regular and extended diapausing NCR. Discussed some issues that have come up with APHIS when shipping insects of different genotypes, diapausing, rotational resistant, etc. Various permits will be required in the future when shipping these various insects. Adjourn for the day. The group decided to begin at 8:30 AM on Tuesday. The group will meet at 5:45 PM for dinner. Tuesday, January 27, 2009 Elson Shields began by discussing some other items or issues that could be brought up after finishing the state reports. Perhaps we could being talking about the rewrite, and discuss some issues that could be brought up during the joint meeting with NC205. Management IL  Discussed a trap crop project that they are working on using late planted corn in strips planted into soybean fields. The idea is to trap crop the WCR variant in these areas. General finding was that trap crops did not work very well or as intended for what would be needed on large grower fields. IN  Bledsoe told of a a graduate student looking at a 10-20% refuge in the bag strategy who is currently processing most of the data. They did not see the temporal shift when using the refuge in bag strategy compared to the normal strategy. They saw damage to neighboring corn plants next to non-transgenic plants, resulting in lesser yield. Also, they are doing work trying to sample the variant beetle by different means, including examining beetles for soybean feeding. IA  Tollefson discussed research by Gassmann in which insecticide treatments on transgenic corn studies were conducted. Improvement in root protection was very slight, and even then, from very little injury to even less injury. Tollefson has been looking at rootworm tolerance in European corn hybrids because they cannot use transgenic nor afford soil insecticides. There are differences in tolerance with some of their varieties. KS  Did similar studies with transgenic and soil insecticides, but had very little damage in their studies. MI  Looking at the secondary soil pests, including many of the grub species that seem to be getting worse. A question was brought up about the winter cutworm. MN  They are doing various studies with transgenics, volunteer corn, and crop rotation. They discussed various surveys about transgenic use and compliance with IRM requirements. Mentioned their overall transgenic performance trials, including transgenics plus soil insecticides. Then they discussed the issue with the diapausing NCR problem in the state. They also mentioned their studies on the role of volunteer corn with the two rootworm species, and whether the corn influences egg laying. Had a lot more WCR beetles in the fields with higher levels of corn; was not as evident with NCR. Results show that the greater the beetle activity, the lesser the yield. Discussed efficacy studies with the various Bt events. There appears to be some differences between WCR and NCR control, with NCR being poorer. They finished discussing their studies on transgenic plus insecticides. There was a general discussion about the performance of Agrisure . There are some instances where the material does not perform as well as the other two transgenic families. MO  discussed the work with rootworm resistant colonies, and then their studies with feeding stimulants. They are looking for native resistance to rootworms in corn, including having released a population of native resistant corn. Some of these lines have been shown to have antibiosis. The committee went back to some information from Iowa, in terms of looking for the variant in eastern parts of the sate, and the diapausing NCR in the next group of counties to the west. The variant is currently in the far NE and EC parts of the state. He then discussed some concerns with the yellow traps, and research when applying soil insecticides to transgenics. NE  a report was given on their studies looking at late season dynamics of WCR with transgenic corn. They also reported on using RNA interference techniques to examine useable genes within the insect as it might relate to resistance. Also are looking at cyclodine resistance as a marker for understanding the population dynamics and movement of WCR. OH  talked about a students work with late planted corn using both long and short maturity hybrids. As part of that, they also looking at silk feeding from adult WCR and JP. Then they discussed efficacy work with transgenics. TX  Doing southern corn rootworm efficacy trials with transgenics. They reported that a lot of work is being done on silage work, mainly because there is an increase in dairies in the state. NY mentioned earlier work in that state on silage corn. WI  Reported on work with soil insecticide on transgenics, and how you seldom see improvements in root ratings but often see a very slight improvement on yields. Also, they are looking at the economics of using insecticides and transgenics as insurance treatments. Ontario  Talked surveying growers compliance with IRM requirements in the province, and their interactions with their government regulatory agencies on future IRM policies. They are still seeing the odd millipede issue on corn seed. Lance Meinke asked about what is happening with fiprinol (Regent) as an infurrow soil application treatment, and the possibility of loosing it. Numerous comments were made. The committee then broke for lunch, with the afternoon session beginning at 1:15 PM. Elson asked if there are any additional information for the state reports. Potter discussed a bimodal peak he sees with WCR in volunteer corn. Tom Sappington mentioned the problem with not being able to get seed from companies. The publication committee of ESA is developing an ethic statement that anyone publishing in ESA journals would have to make all materials available to anyone who wants to repeat those experiments. The issue was discussed on how it would or might work. Ken Ostlie brought up a discussion on the future of CRW management. With so much transgenic use as insurance, how do we position ourselves for these changes? How do we position ourselves to deal with possible resistance? What are the relationships between the companies, EPA, USDA, universities research and extension, etc.? The committee discussed the idea of a letter to the companies about some of these concerns, which had been discussed at last years meeting. Could any of this be made part of the rewrite for NCCC46? Elson asked if there is interest in drafting a letter. As during last years meeting, this issue was discussed in detail. Should we include constituent groups like the corn grower associations and others to get involved in this? Should we write a letter? Should we write an article/journal paper for ESA, perhaps the Forum section of JEE? Perhaps any such paper or group of papers should also bring in the views of EPA and ABSTC. This will be brought up and discussed in our joint meeting tomorrow with NCR205. Pat Porter, Tom Sappington, and Mark Boethel will take the lead and develop an outline of a possible paper, meeting this evening to jot down some thoughts and ideas. Business Meeting Nomination committee selected Eileen Cullen as the new secretary. She accepted. The site selection committee selected Madison, WI. Approved. Target the same last week in January, 25-29, 2010 with NCR46 being Jan 28-29 after NCCC205. Moved and approved. Will need to determine NCCC205 interests in having the joint meeting. BREAK The committee then began a discussion of the rewrite that will need to begin next year. Modified Objectives for the next rewrite. 1. Evaluate registered and experimental corn rootworm management tactics (including rootworm-resistant transgenic hybrids) for their impacts on rootworm biology and implications they may have on the agroecosystem throughout the United States and Canadian corn growing regions. 2. Coordinate a national research investigation into reported yield enhancements associated with new insecticidal seed-coat in the absence of corn rootworm injury. (Lance: this one is pretty much completed. Fuller is summarizing the data.) 3. Systematically design and implement research on rootworm mating, dispersal, survival, and host range across environments and production systems. 4. Characterize the impacts of gene flow on the spread of behaviorally and physiologically resistant pest strains and the resulting needs for designing resistance management plans. These research needs may be identified by and used in resistance-management computer simulation models. 5. Investigate the biology and impact of emerging and/or secondary below ground pests on corn hybrids and evaluate management options. 6. Facilitate national and international information exchange on corn rootworm management as it relates to other crop management practices, agroecosystem and regulatory issues. 7. Develop and maintain a public website that collates current knowledge on rootworm biology and management across regional production systems. 8. On an as-needed basis, publish statements that draw on published research and the expertise of the committee to address critical issues pertaining to existing or emerging insect control technologies. 9. (new) Evaluate the impacts of below-ground pests on plants grown for biofuels or feedstocks. It was again mentioned that there would be a meeting with Dow and then Pioneer this evening is in Amundson Hall, Room 124, at 7:30 PM. This is a separate meeting from NCCC046. The meeting then adjourned.

The NCCC-46 publication "the corn rootworm management guide" is in final layout production and is scheduled for publication in 2009.

A reconstructed history of WCR range expansion through North America was finished, resulting in first accurate and updated map in 25 years.

In cooperation with EPA scientists USDA-NCARL have selected three genetically diverse non-diapausing WCR lines, which have undergone several generations of selection for Cry3Bb1 resistance. The genetic makeup of these colonies are being analyzed and mapped by the EPA. The resistant lines have developed about a 6.5 fold resistance level.

Field and lab studies of WCR mating dynamics indicate that there is assortative mating, with large females being preferred by males. There was no evidence of any effect of male size upon mating patterns. This information is important because female weight has been shown to be both positively and negatively affected by exposure to Bt toxin, depending on exposure time, duration, and density.

Male WCR mated an average of 3.5 times during their lifetime when given continuous access to unmated females. However, "old" males (more than 10 days after initial mating), usually did not mate at all. This is critical information to assess the success of the Bt/refuge concept, as the models currently assume that males are able to mate equally well from eclosion until death.

Demonstration of egg-to-adult WCR development on Miscanthus x giganteus (candidate feedstock crop for the cellulosic ethanol industry) raises questions about the suitability of this perennial grass for Corn Belt cultivation. Failure to assess the capacity of Miscanthus to become a reservoir for pest rootworms, could compromise corn pest management. Uncertainty about WCR interactions with Miscanthus in the field warrant caution before promoting the widespread cultivation of an alternate WCR host on 7 million acres.

Wisconsin entomological field research continued during summer 2008 to collect a third and final experiment year from 5 case study farms. Data for Obj. 1 and 2 of a current USDA CSREES North Central Region IPM project (Cullen and Mitchell) are fulfilled by Variant WCR trapping data from non-corn crops paired with first year corn root ratings and insecticide or Bt corn rootworm hybrid treatment strip trial yield measurements (PI, Cullen) and economic analysis (Co-PI, Mitchell) from the same fields the subsequent year. A total of 18 fields (14 soybean, 4 winter wheat stubble) were sampled across the four on-farm study sites. None of our case study farms grew alfalfa in 2008. 12 yellow sticky traps were placed in an evenly spaced grid in each field during the last week of July. Traps were checked, WCR beetle numbers totaled, and traps replaced every 7 to 10 days. The sampling period extended 6 weeks, and traps were removed in early September. Total beetles/trap/day (B/T/D) was calculated for each week interval, the entire 6 wk sampling period and for each individual trap location within each field. Additionally, during summer 2008, 21 first year corn fields in Rock and Walworth Counties that were trapped as non-corn crops (soybeans and wheat) in 2007 for Variant WCR were evaluated by root injury ratings from replicated CRW treatment efficacy (soil insecticide or Bt corn rootworm hybrid) and yield strip trials to evaluate preceding crop, Variant WCR numbers in relation to the 5 B/T/D economic threshold for first year corn, and treatment efficacy and economics by first year corn management decision paradigm. This project has now obtained IPM non-corn crop scouting data- first year corn treatment decision efficacy and economic data for two complete cycles 2006-2007 and 2007-2008, respectively. The 18 soybean and wheat fields trapped in 2008 will be evaluated in 2009 as first year corn fields to complete a third 2008-2009 data set. During the remainder of this project, Mitchell and Cullen will be analyzing experimental data to identify the most profitable combinations of Variant WCR scouting protocol, economic threshold, and crop rotation.

Extension PRODUCTS fostered by this project include incorporation of the Variant WCR trapping survey network into the WI Department of Agriculture Trade and Consumer Protection (WDATCP) Pest Survey http://pestbulletin.wi.gov/ leveraging USDA CSREES NCIPM funding and research/extension efforts into a self-sustaining state IPM monitoring program. An Extension publication is in preparation by Cullen to communicate project findings to growers and crop consultants. Mitchell developed an initial Spreadsheet Decision Aid titled "Calculate Your Net Benefit and Break-Even Probability for Western Corn Rootworm Control Using Soybean Trap Counts" http://www.aae.wisc.edu/mitchell/extension.htm.

2006-2008 surveys that documented relative densities of NCR emerging from first-year corn and associated level of root injury in eastern Nebraska clarified the geographic variability of NCR infestation and demonstrated that NCR injury in most first-year cornfields in eastern Nebraska was not great enough to warrant grower investment in a rootworm control tactic. This information has been used by growers to make more informed NCR management decisions in 2007-2009.

Volunteer corn in soybeans following triple-stack corn in Indiana was found to express glyphosate-tolerance 85% of the time, and Bt (Cry3BB1) 65% of the time. Of the plants expressing Bt, about a third exhibited high levels of damage from larval WCR feeding, indicating that expression of toxin may not be as high in the non-hybrid volunteer corn. This represents a novel food source for WCR larvae in soybean fields and should be aggressively treated with herbicide early in the year to minimize RW exposure to potentially lower toxin levels.

Ongoing Illinois study demonstrated that mate-seeking refuge WCR males thoroughly disperse into transgenic corn. This information supports general movement assumptions integral to WCR IRM strategy. However, significant movement of unmated females from refuge into transgenic corn (perhaps related to low male density in refuge) suggests that some assumptions about refuge function are not being met.