NC246: Ecology and Management of Arthropods in Corn
(Multistate Research Project)
NC246: Ecology and Management of Arthropods in Corn
Duration: 10/01/2015 to 09/30/2020
Statement of Issues and Justification
Over 80 million acres of field corn (Zea mays) and 600,000 acres of sweet corn, worth about $65 billion and $1 billion respectively, are grown in the U.S. each year. The European corn borer (ECB) (Ostrinia nubilalis) and western corn rootworm (WCR) (Diabrotica virgifera virgifera) account for over $1 billion each in control costs and grain losses annually. Rootworms are particularly problematic because of their propensity to evolve resistance to management tactics, including crop rotation (Gray et al. 2009), insecticides (Meinke et al. 1998), and now Bt toxins (Gassmann et al. 2011, 2014).
There are numerous other corn insect pests that cause significant economic loss to U.S. corn producers. The southwestern corn borer (Diatraea grandiosella) causes several million dollars in damage to corn in the Western High Plains (Morrison et al. 1977). Recently, the sugarcane borer (D. saccharalis) has emerged as an important corn pest in the south (Castro et al. 2004, Porter et al. 2005). Significant foliage and ear feeders include the two most important lepidopteran pests of corn in the southeast, corn earworm (Helicoverpa zea) and fall armyworm (Spodoptera frugiperda) (Buntin et al. 2004). Losses attributed to corn earworm in sweet corn can be as high as 50% (Wiseman 1999). The western bean cutworm (Striacosta albicosta) has recently expanded its range to become an increasingly serious corn pest as far east as Pennsylvania and north into Canada (e.g. Michel et al. 2010). Among underground pests, the northern corn rootworm (NCR) (D. barberi) is a perennial pest in much of the Corn Belt, and the southern corn rootworm (D. undecimpunctata howardi) is occasionally important, especially in the southeast. Many secondary pests, such as wireworms (Elateridae) and white grubs (Scarabaeidae), can cause serious local problems, and may be resurging with the decrease in soil insecticides used to manage rootworms following wide adoption of transgenic Bt corn. Widespread prophylactic use of neonicotinoid seed treatments to control these secondary soil pests may not be sustainable because of increasing environmental concerns (Mullin et al. 2005, Krupke et al. 2012).
Established in 1953 to address ECB, earlier versions of NC-205 evolved to include a broader array of corn pests. First other stalk-boring Lepidoptera were included, and then other above-ground Lepidoptera. This was a natural progression for the committee, as 1) these pests increased in economic importance, and 2) a pest species does not exist in isolation, but as part of a pest complex and arthropod community. NCCC-46, the Multistate Research Coordinating Committee ‘Development, Optimization and Delivery of Management Strategies for Corn Rootworms’, originated in 1964 as WCR was spreading eastward from the Great Plains into the Central Corn Belt (Gray et al. 2009). NCR was already an economic pest in the Corn Belt, but it was becoming clear that WCR was an even bigger threat to corn production.
During the 1990s, NC-205 and NCCC-46 began to co-locate and meet sequentially during the same week. This was in part because several members were on both committees, but more importantly to invite Industry for discussing the deployment, efficacy, non-target effects, and insect resistance management (IRM) implications of transgenic Bt corn, topics of broad interest to both committees. This sequential meeting model became even more valuable upon the introduction of Bt transgenic corn targeting corn rootworm in 2003, its rapid adoption (Rice 2004), the stacking of genes targeting both corn rootworm and corn Lepidoptera in the same plant, and the discovery of WCR field resistance to Cry3Bb1 toxin (Gassmann et al. 2011). Because of the increasing interaction of NC205 and NCCC46, merging of the committees was discussed during the 2014 annual committee meetings. It was felt that a formal merging of the committees would be of mutual benefit, both scientifically and logistically, and after additional discussion, each committee voted to merge. Therefore, this NC-205 renewal proposal reflects the decision to merge the committee membership and address the larger corn insect pest complex, with emphasis on above-ground Lepidoptera pests and below-ground Coleoptera pests.
Since the commercial release of Bt transgenic corn against ECB in 1996 and against rootworms in 2004, a revolution in corn insect pest management has occurred. Seed companies continue to develop genetically-modified (GM) crops for pest protection. New GM corn hybrids have resistance to a broader range of lepidopteran pests, some have resistance to coleopteran pests, and most current GM hybrids have genes targeting both Lepidoptera and Coleoptera. This technology often eliminates the need to store and handle insecticides and it increases the efficiency of grower operations and pest control (Rice 2004, Sappington 2014). However, the development of resistance by WCR to some Bt toxins is threatening to reverse these gains. Keeping abreast of these changes with timely and relevant research over an area as large and diverse as the U.S. Corn Belt lends itself to a coordinated, committee approach.
Bt corn acreage in the U.S. has increased from 8% in 1997 to 80% in 2014. At this level of adoption, the potential for resistance increases. Research conducted by this committee was used to develop models predicting the rates of resistance evolution and efficacy of refuge in preventing resistance. This led to the IRM approach that used a 20% independent refuge planting; however, as GM technology has evolved, so has IRM. Recently deployed GM corn hybrids use multiple genes that target ECB and WCR. The IRM plan for these hybrids requires a smaller refuge, and seed mixtures (Bt and non-BT) are now being deployed. The models supporting these IRM modifications were constructed using the best information available, but a number of assumptions had to be made. These assumptions must be tested and research conducted to move them from assumptions to quantified variables. Furthermore, information is needed on the economics of this evolving technology at the field, farm, and regional levels. Addressing these knowledge gaps forms the basis for several objectives of the project. The long-term goal of our research is to develop sustainable ways to manage the corn insect pest complex. This is a high regional priority, and in the context of demonstrating sustainable practices, it also is an important national priority.
Relationship between pest control technologies and the agricultural environment. Since 2004 the percentage of U.S. corn acreage with seed-applied neonicotinoids has increased dramatically, and they are now used on virtually all non-organic corn acres. However, across most of the Corn Belt the targeted early-season pest species are sporadic and patchily distributed, and most crop fields do not experience annual economic infestations (Boethel 2012). This begs the questions: “How much protection do neonicotinoid seed treatments offer?” and “What is the risk posed by the most common early season pests in the region?”
Neonicotinoids are attracting attention for their potential role in pollinator declines and possible contamination of surface waters (Goulson 2013, Hladik et al. 2014, van der Sluijs et al. 2014). Seed-applied active ingredient can persist in soil for up to two years and move into aquatic systems where it can simplify aquatic invertebrate communities (Laurent and Rathahao 2003, Krupke et al. 2012, Van Dijk et al. 2013). A recent Canadian study revealed substantial ground water contamination with thiamethoxam (Main et al. 2014). It is clear an evaluation of the effects of seed treatments upon a range of non-target insects in and around cornfields is warranted.
Ecology, evolution, genetics, and behavior of corn arthropods. The WCR and ECB genomes, and the WCR transcriptome, were recently sequenced through international efforts involving several Committee members. Annotating, mining, and maintaining these rich and powerful databases will require an ongoing, collaborative community effort. These genomics gateways will facilitate probing the genetic basis of many important pest traits, including insecticide resistance (Alves et al. 2006), behaviors relevant to pest status, and insect-plant interactions. Furthermore, the potential role of microbial associates on these traits can begin to be assessed. Development of genetic markers and genomics tools by Committee members is allowing more sensitive population genetics studies for estimating dispersal distances of corn insects. Spatial and temporal aspects of adult movement have proven difficult to characterize in both WCR and ECB, despite significant recent advances by Committee members. A comprehensive understanding of mating behavior and dispersal is critical for modeling development and spread of resistance to Bt corn, estimating gene flow, and implementing IRM.
The introduction of Bt transgenic corn hybrids and neonicotinoid seed treatments, have increased the need for addressing critical regional issues largely because the agricultural landscape has changed. Changes in corn rootworm biology, pest management technologies, and regulatory issues over the last several years have illustrated the fact that much of our past information and research about these systems must be re-evaluated. More information is needed on geographic patterns of ECB genetic variation, voltinism, pheromone blend, sensitivity to Bt, and the influence of host plants. Promotion of an IPM-based approach to the deployment of rootworm-Bt products has reached a critical cross-roads, as resistance to some toxins has led to recommendations from various quarters to layer multiple control tactics on Bt corn, including conventional insecticides, without assessing actual need. The Committee has an interest in use of Bt and other insect control tactics in an economically viable and sustainable manner that will prevent or delay the onset of insect resistance. Ensuring long-term durability of these tools requires IRM strategies that are compatible with production practices.
IPM and IRM systems for the corn arthropod complex. Monitoring for resistance among target pests to plant-incorporated insecticidal toxins remains an EPA mandated component of IRM for insect pest-targeting transgenic corn (Siegfried and Spencer, 2012). Being able to detect insecticide resistance is necessary to determine if control failures are because of resistant insects or other factors, determine the extent of the resistance, and design resistance mitigation programs. This is particularly important for WCR which was recently confirmed as resistant to Cry3Bb1 and mCry3A (Gassmann et al. 2011, 2014). There is an urgent need to characterize resistance of rootworms to Cry3Bb1 and other cry toxins and to develop and deliver IPM recommendations to mitigate rootworm resistance. Recently a decline in Cry1F susceptibility of western bean cutworm has been reported (Smith et al. 2014), so a geographic assessment of Cry1F susceptibility is necessary, as well as a proactive plan to address the risk of resistance to Vip3A and other insecticides. As additional pests become primary targets of transgenic technology, monitoring methodologies and programs will have to accommodate these new target pests.
The ear-feeding guild has gained increased attention during the last decade for several reasons, including the range expansion of the western bean cutworm (e.g. Michel et al. 2010), the association between insect feeding and aflatoxin, and the implications of differential kernel feeding for IRM. This complex includes several Lepidoptera, but also coleopteran and hemipteran pests, which presents significant management and research complications. Basic issues such as accurate quantification of injury and the effects of sequential feeding require characterization, as well as the broader issues relating to IPM and IRM.
In 2013 the cotton bollworm (H. armigera), an Old-World pest, was detected in Brazil (Czepak et al. 2013, EMBRAPA 2013, Specht et al. 2013). This was the first report of this pest in the Americas. An insect capable of long distance migration (Pedgley 1985), it presents a significant risk of entering the U.S. Early detection and response plans for this potential corn pest are an immediate need.
Diverse delivery methods for sustainable management of corn arthropod pests. The audience for the results of this project has grown. It comprise farmers and other ag-professionals, but also policymakers, researchers, educators, concerned citizens, and their expectations are greater than ever before. It is critical that results be packaged as unbiased information for these agricultural and public sectors. While traditional information dissemination is still needed, stakeholders are expecting that information be timely, provided in new formats, interactive, and accessible from their home or office.
A comprehensive IPM system is needed for cost-effective prevention, early detection, rapid diagnosis, and mitigation of new and emerging corn pests that links all stakeholders (e.g. myfields.info). We need to transform how we extend information using mobile technologies and web-based social networks. Defining elements needed to sustain user interests in the system is critical; a positive user-experience leads to increased use and rapid integration of stakeholder inputs. Knowledge gaps in specific areas must be addressed in multiple geographic regions to allow uniform application of the system. Using this approach, a blend of smartphone technologies and social networks with traditional Extension activities will lead to rapid detection and cost-effective management of new and common corn pests.
A Multi-State Approach. Collectively, a multi-state approach to researching the knowledge gaps described above, developing IPM tools and programs, assessing IRM strategies, and implementing technology transfer is appropriate and necessary. Geography plays an important role in how pests interact with other organisms in their environment, and how IPM and IRM strategies are designed and employed. It is this significant spatial effect of population and community dynamics that make a regional project necessary. Lack of knowledge has led to fears by the general public about the potential environmental and health risks associated with adoption of new technologies. Controversy about the effect of GM and seed treatment technology on non-target organisms and human health has fueled public concerns. These fears have the potential of forcing legislation to ban or slow the introduction of these technologies. Answers to questions regarding new technologies should help focus the public's perception of them and allow growers to gain the pest control advantages provided by future technologies.
The proposed multi-state plans will continue to be a model for the development of science-based resistance management programs and risk assessment for other pests, other crops, and future crop protection technologies. Our efforts will provide fundamental advances in the knowledge of pest ecology, genetics, behavior, and evolution. Our work will continue to provide science-based assessments essential to the policy decision-making process, which should help to increase the public's acceptance of environmentally friendly technologies while identifying potential negative impacts that need further investigation. Our work also will continue to lead to more sustainable pest management systems for the corn pest complex. There is ample evidence that the merged NC-205 and NCCC-46 research groups have the skills, collaborative working relationships, and commitment to provide the missing biological information and to incorporate this new information into evolving IPM programs and IRM models.
Related, Current and Previous Work
A CRIS search indicates that there are 54 active projects related to ‘corn Lepidoptera’, ‘corn Diabrotica’, or ‘corn insects’. Of these, 29 are directly associated with NC-205 or NCCC-46, and six projects are led by NC-205 or NCCC-46 collaborators. The remaining 19 projects are broad and typically include a few corn insect pests as components of a general IPM or pest management project covering several crops. Others cover a variety of subjects, such as organic crop production, stored product pests, or biocontrol of insects, and again often focus on a variety of insects or are narrow in scope with respect to a specific corn pest.
Several USDA-ARS Units conduct research on insect pests of corn, including units at Tifton, GA (Crop Genetics and Breeding Research Unit, Crop Protection and Management Research Unit), Stoneville, MS (Southern Insect Management Research Unit), Gainesville, FL (Insect Behavior and Biocontrol Research Unit), Mississippi State, MS (Corn Host Plant Resistance Research Unit), Fargo, ND (Insect Genetics and Biochemistry Research Unit), Brookings, SD (Integrated Cropping Systems Research Unit), Columbia, MO (Plant Genetics Research Unit), and Ames, IA (Corn Insects and Crops Genetics Unit). The Corn Insects and Crops Genetics Unit at Ames, IA conducts considerable research on lepidopteran and Diabrotica corn pests, and several of its research scientists are long-standing members of NC-205 and NCCC-46.
A NIMSS search indicates three active Multistate Research Projects other than NC-205 that involve corn arthropod pests: NE-1332 Biological Control of Arthropod Pests and Weeds; S-1052 The Working Group on Improving Microbial Control of Arthropod Pests; and W-3185 Biological Control in Pest Management Systems in Plants. None of these projects deal with the entire array of natural enemies (i.e. predators, parasites, and diseases) for even a single corn insect pest, so NC-205 and NCCC-46 will continue to deal specifically with natural enemies of corn pests. Our committees have established cooperative interactions with members of these biological control committees and we will continue to coordinate efforts with other regional projects investigating biological control.
There are two active Coordinating Committees besides NCCC-46 that involve corn arthropod pests: NECC-1008 Improving Sweet Corn: Genetics and Management and NECC-029 Northeastern Corn Improvement Conference. NECC-029 is quite broad, addressing a few facets of corn rootworm resistance management only in the northeast region. NECC-1008 simply provides a forum for information exchange on current and emerging sweet corn pests.
There are several active Education/Extension and Research Activity Committees that in some part address corn arthropod pests. Some are based largely on the principles of IPM (e.g. NCERA-224 IPM Strategies for Arthropod Pests and Diseases in Nurseries and Landscapes, SERA-003 Southern Region Exchange Group for IPM), but these are very broad and address corn arthropod pests only in brief. Others address biological control or resistance management (e.g. NCERA-220 Biological Control of Arthropods and Weeds, WERA-060 Management of Pesticide Resistance), but their primary purpose is information exchange and awareness, not in-depth and collaborative research. We know of no other research projects engaged in a regionally coordinated research that focuses on the ecology, evolution, genetics, behavior, and management of corn arthropod pests.
NC-205 and NCCC-46 have held overlapping meetings with one another, industry, and other stakeholders (e.g. EPA) for over a decade to share ideas in the rapidly evolving area of transgenic corn. Because stacked hybrids contain genes that target both corn Lepidoptera and corn rootworm, it will be essential to continue to coordinate research and extension activities. Growers will need consistent recommendations from both groups. Effective coordination between the committees is already the norm, hence the decision to merge.
Relationship between pest control technologies and the agricultural environment
Without a corresponding increased threat from insect pests, neonicotinoid seed treatments are now used on virtually all non-organic corn acres. These seed treatments are deployed outside of an IPM framework in that they are not guided by field histories or pest infestation levels. The early-season pest species targeted by these seed-applied insecticides are sporadic and patchily distributed, meaning that the majority of crop fields do not annually experience economically significant populations of the pest species; thus, the insecticide has little opportunity to provide a benefit (Higley and Boethel 1994, Pedigo and Rice 2008). Most producers may be unaware that neonicotinoids only target a subset of the pest complex for a relatively brief period in each growing season and that the pests targeted are infrequently encountered and often require no intervention.
Neonicotinoids research has recently been directed at their potential role in pollinator declines and for evidence suggesting that neonicotinoid contamination of surface waters can be negatively correlated with abundance of some vertebrate and invertebrate species (Goulson 2013, Van Dijk et al. 2013, van der Sluijs et al. 2014). These studies are correlational in nature, and it is clear that there is a poor understanding of the potential influence of such widespread adoption of insecticides with such a high toxicity. The LD50 of honey bees for clothianidin is just 3 ng (Iwasa et al. 2004), demonstrating that minute concentrations of neonicotinoids can significantly affect or kill non-target arthropods. The role of planter dust has received attention recently (Krupke et al. 2012), but this exposure route may be mitigated. Only a minority of the seed-applied active ingredient is actually absorbed by the plant and the material left behind can persist in soil for up to two years and move into ground water where it can simplify aquatic invertebrate communities and significantly retard decomposition (Laurent and Rathahao 2003, Krupke et al. 2012, Van Dijk et al. 2013). A recent study conducted in the prairie wetlands of Canada revealed substantial ground water contamination with thiamethoxam, a seed treatment of canola grown in this region (Main et al. 2014).
Investigate the ecology, evolution, genetics, and behavior of corn arthropods
A large-insert bacterial artificial chromosome library, DvvBAC1, was constructed from size-selected WCR genome fragments representing ~4.5X genome coverage (Coates et al. 2012). The Diabrotica Genetics Consortium, which includes several Committee scientists, has organized the recent sequencing of the WCR genome and transcriptome (see Miller et al. 2010). Sequencing was made possible by the critical development of an inbred WCR strain at the ARS Brookings laboratory. However, the WCR genome is huge (2.56 Gbp) and highly repetitive making assembly of sequence fragments very difficult (Coates et al. 2012; 2014a). Results from genotyping resistant and susceptible WCR indicate the frequency of resistance alleles can be estimated in field populations (Wang et al. 2013). Quantitative trait locus (QTL) mapping of Cry1Fa and Cry1Ab Bt toxin resistance in ECB revealed that gene products can modify gene expression of unlinked loci (Coates et al. 2011a; 2013a). A team led by Committee scientists developed and verified 817 single nucleotide polymorphism (SNP) markers (Coates et al., 2009b) from WCR EST libraries of the head (Knolhoff et al., 2010) and midgut (Siegfried et al., 2005). Transgenic Bt corn expressing the Cry1Ab toxin and targeting ECB is not effective against western bean cutworm (Catangui and Berg 2006), and although Bt corn hybrids that express Cry1Fa toxin are fairly effective (Rice and Dorhout 2006), ears on these hybrids can still sustain significant feeding damage (Michel et al. 2010). In response to mounting concerns over possible western bean cutworm field resistance to Cry1Fa corn, methods were developed for laboratory rearing and assaying for Bt toxin tolerance using toxin overlay assays (Dyer et al. 2013).
Pheromone races of ECB ("Z" and "E") coexist in the eastern U.S., and are partially isolated genetically (Dopman et al. 2005). The Z-race is widespread east of the Rocky Mountains, but the E-race is restricted to the northeastern U.S. and along the Atlantic seaboard (O'Rourke et al. 2010). Based on carbon isotope signatures, ~18% of E-race adults captured in New York had developed on non-corn (C3) plants compared to only 4% of Z-race moths (O'Rourke et al. 2010). Pheromone traps are often used to separate the morphologically indistinguishable males of E- and Z-races, but imperfect fidelity has resulted in difficulties in associating genetic differences with pheromone race. A novel molecular genetic assay was developed to detect a SNP fixed in the pheromone gland fatty acyl-reductace (pgfar) gene between E- and Z-race ECB, which is >98% accurate compared to gas chromatograph phenotypes from corresponding females (Coates et al. 2013a, b). Populations of ECB recently have been collected from several isolated locations in PA, genotyped at neutral SNP marker loci, assayed for pheromone genotype, and analyzed for C-isotope signatures.
With the advent of pyramided Bt corn (corn with two or more Bt toxins with different modes of action targeting one or closely related insect species), refuge has evolved from a structured refuge approach to an unstructured refuge approach that uses a blend of Bt and non-Bt corn seed (i.e. refuge in a bag). Theoretically, pyramids require less refuge (Gould et al., 2006; Zhao et al., 2003) and EPA has allowed reduced refuge for some pyramided corn (Coons, 2009). However, recent modeling suggests larval biology and behavior, such as dispersal between Bt and non-Bt corn, may compromise seed blends as a resistance management strategy (e.g. Goldstein et al. 2010, Razze et al. 2011, Yang et al. 2014). European corn borer neonate dispersal has been found to be greater on Bt corn compared with non-Bt corn (Razze and Mason 2012). Recent research has indicated that larvae of several Lepidoptera species (e.g. European corn borer, fall armyworm) exhibit more plant-to-plant movement than was expected, particularly in early instars.
Microbial associates of insects mediate many aspects of insect biology, including interactions with host plants and defense against natural enemies (Frago et al 2012, Hansen and Moran 2014, Oliver et al 2014). Many of these interactions are recently discovered, indicating that we are only beginning to uncover the microbial dimension to plant-insect interactions. Bacterial associates can down-regulate plant defenses against the insect (Chung et al. 2013), increase insect resistance to pesticides (Kikuchi et al. 2012), and influence the pest status of their insect host on crops (Hosokawa et al. 2007). Among corn pests, bacteria associated with western corn rootworm interact with plant defenses (Barr et al 2010), an effect initially attributed to the mitochondrially-inherited bacterium Wolbachia (Giordano et al 1997). However, a study involving a MO committee scientist found no effect of Wolbachia on corn plant defense (Robert et al. 2013), suggesting that other microbial associates (e.g. gut or oral bacteria) may instead play a role. Preliminary analyses of genomic DNA and transcriptome sequences have revealed multiple insect, plant, fungal and bacterial viruses (or phages) associated with corn rootworms. Soil core and pitfall samples of arthropods have been taken from replicated long-term 2-yr and 4-yr crop rotation plots in Iowa, which have exhibited differences in yield and soil structure (Cruse et al. 2010). DNA isolation is underway, and primers for PCR amplification of mitochondrial cytochrome oxidase I (COI) have been obtained and modified with index sequences for barcode identification of taxa.
WCR populations are not genetically differentiated in the Corn Belt as a consequence of range expansion (Kim and Sappington 2005; Flagel et al. 2014), so sampling and genetic characterization of populations from the native home range is underway. Preliminary analyses indicate genetic structuring exists in this area, a precondition for estimating spatial gene flow. Considerable progress has been made in estimating short-range WCR dispersal behavior (Spencer et al. 2009; 2013). Overwintering populations of fall armyworm host races in Florida and Texas re-infest the northern and eastern U.S. each summer via long-distance migration. Host races are distinguishable based on mitochondrial DNA haplotypes. Recent research extended the haplotype map to Mexico and South America, and confirmed that regional differences are stable over time (Nagoshi et al. 2015).
Develop and assess IPM and IRM systems for the arthropod complex in corn
Annual assessments of susceptibility of target pest species such as the European corn borer and fall armyworm have been ongoing. This research has involved diagnostic bioassays (Marcon et al. 2000, Siegfried et al. 2007) or in some cases F1 and F2 screening approaches (Siegfried et al. 2014, Velez et al. 2013) to isolate resistance alleles and assess frequencies. In instances where resistance has been identified, specific research to identify inheritance patterns, fitness costs (Crespo et al. 2010, Pereira et al. 2011, Petzhold-Maxwell et al. 2013, Velez et al. 2014), and molecular mechanisms of resistance have been conducted (Crespo et al. 2011, Coates et al. 2011). Bioassay of Bt toxins have relied on standard methods involving surface treatment of artificial diet with toxin preparations (Marcon et al. 1999) and has provided consistent assessments of susceptibility for more than a decade (Siegfried et al. 2006, Siegfried and Hellmich 2012, Siegfried and Spencer 2012). A variety of biochemical, molecular and genomic tools have been developed to assess mechanisms of resistance (Coates et al. 2011, Crespo et al. 2011).
Western corn rootworm resistance to Cry3Bb1 corn was documented in western corn rootworms collected from IA cornfields previously reporting greater than expected damage to corn roots from rootworms in 2009 (Gassmann et al. 2011). Additional IA cornfields were identified with Cry3Bb1 resistance in 2010 (Gassmann et al. 2012). The resistance was found to persist, and in analysis of western corn rootworms collected in 2011, resistance was found to Cry3Bb1 corn, mCry3A corn, and cross-resistance between Cry3Bb1 and mCry3A (Gassmann et al. 2014). Analysis of western corn rootworm collected from northeast NE fields with reports of greater than expected damage to corn roots from rootworms indicated resistance to Cry3Bb1 corn (Wangila et al. in press).
Pleau et al. (2002) altered dietary constituents of a southern corn rootworm larval artificial diet and measured subsequent effects on western corn rootworm growth. They found that optimizing pH, removing formalin, and adding plant adjuvant nearly doubled growth of western corn rootworm larvae from the previous diet. There is a wealth of rearing literature with other insects, but nothing in the literature since that time on western corn rootworm. Our group has considerable experience with rootworm (Hibbard et al. 2010), diet formulations for other insect species (Zou et al. 2013), rootworm feeding behavior (Bernklau et al. 2013), and microbes associated with rootworms (Demantheis et al. 2012a,b). We plan a series of experiment aimed at eventually developing an improved, standardized artificial diet for western corn rootworm larvae that can be used in diet-toxicity assays with all toxins targeted for transgenic rootworm control and develop an efficient artificial diet system capable of rearing western corn rootworm larvae all of the way to beetle emergence.
As noted above, questions have arisen with respect to larval movement and the efficacy of seed blends in slowing the development of resistance. Associated with movement are the consequent effects of larval feeding on corn ears that are the result of cross pollination between Bt corn and non-Bt corn (e.g. Chilicutt and Tabashnik 2004, Burkness et al. 2011, Burkness and Hutchison 2012, Kang et al. 2012, Yang et al. 2014). Reduced mortality was observed by ECB larvae feeding on kernels of Bt corn expressing Cry1Ab toxin (Burkness et al. 2011), and recent studies have indicated that some species (e.g. corn earworm) may exhibit differential feeding on kernels expressing different, or no, Bt toxin. Differential expression of of Bt toxins in corn ears has been suggested to effect the evolution of resistance in Lepidoptera that feed primarily in the ear (e.g. corn earworm, western bean cutworm) (Burkness et al. 2011, Onstad et al. 2011).
Economic injury levels, economic thresholds, and sampling tools have recently been developed for western bean cutworm (Paula-Moraes et al. 2011, 2012, 2013). However, the utility of these tools can be compromised by the presence of other ear-feeding pests, particularly non-lepidopteran species. There are several kinds of insects that feed on corn ears besides Lepidoptera. These include the brown stink bug (Euschistus servus), green stink bug (Acrosternum hilare), the southern green stink bug (Nezara viridula), the brown marmorated stink (Halyomorpha halys), bug picnic beetle (Glischrochilus quadrisignatus), and the dusky sap beetle (Carpophilus lugubris) (Flanders et al. 2013). Several species may occupy the ear at the same time, and current research is being designed and conducted to address differentiating injury types, the effects of competition, and consequent effects on IPM and IRM.
The cotton bollworm, an ear-feeder, was detected in 2013 in Brazil (Czepak et al. 2013, EMBRAPA 2013, Specht et al. 2013). A strong flyer capable of long distance wind assisted migration (Pedgley 1985), bollworm moths have recently been captured in Costa Rica and Puerto Rico. To date, no bollworm have been found in very limited surveys of larvae in corn and light trap evaluations in the southern U.S., but it is expected to be found in coming years and/or as monitoring increases. Once in the U.S., recent modeling estimates its range would be similar to that of the corn earworm. Early detection and response plans for this potential pest are an immediate need.
The corn seed market has become more concentrated with the four largest firms accounting for 86% of the market in 2010 (Shi et al. 2013). Factors contributing to this concentration include a desire to exploit asset complementarities, mitigate contractual hazards, and/or secure market power (Graff et al. 2003; Shi 2009). As firms secure market power, they focus less on price competition and more on non-price competition, which is beneficial to them, but not necessarily to farmers and the efficacy of IRM. The increased pyramiding and stacking of GE traits and efforts to obtain less stringent IRM requirements are examples of non-price competition that could positively or negatively affect farmers and IRM efficacy. Pyramiding modes of action for an insect target tends to reduce the risk of resistance, while stacking modes of action for different insect targets can increase the risk of resistance with negligible economic benefit in regions where some insect targets do little damage. All else equal, making IRM less stringent by reducing refuge size requirements tends to increase the risk of resistance, though it could instead reduce the risk of resistance if it improves farmer compliance (Hurley 2005).
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.
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.
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.
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.
MethodsObj. 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. IN will coordinate an effort to survey fields across the Corn Belt to quantify the population densities of key pests, and characterize the protection offered by neonicotinoid seed treatments by quantifying the levels of insecticide present in treated seeds and seedlings at various points throughout the season, using established LC-tandem mass spectrometry. The results will be used to determine the degree of overlap between populations of early season pests in the region and the window of efficacy afforded by neonicotinoid seed treatments. 1b. Evaluate possible effects of insecticidal seed coatings on non-target beneficial insects. IN and PA will lead U.S. efforts to evaluate the effects of seed treatment upon a range of beneficial insects, including pollinators, important predators and species that are particularly charismatic and/or imperiled. Abundance and diversity studies of non-target insects using a combination of survey techniques will be conducted. Candidates for further study may be subjected to more detailed dose/response studies in laboratory settings that include estimates of sublethal effects. 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. NE, IA, IL, MO, and SD will lead and collaborate in various projects under this subobjective. A new WCR BAC library will be constructed to provide more complete genome representation than the earlier DvvBAC1 library (Coates et al. 2012; Wang et al. 2013). Clones containing WCR Bt-resistance candidate genes will be identified using a BAC super-pool screening strategy (Coates et al. 2009b), followed by purification and sequencing (Coates et al. 2012). mRNA will be extracted from WCR larvae exposed to Bt Cry3Bb1 and Cry34/35 toxins, nematode and entomopathagenic fungi. This mRNA will be converted to cDNA for full transcriptome sequencing, and these data will be used for gene annotation. Reference transcriptomes for both western bean cutworm and ECB midgut tissue will be constructed from overlapping paired-end reads from Illumina MiSeq insert libraries. RNA-seq data from Cry1Fa resistant and control larvae will be mapped to their respective reference transcriptomes to identify differentially-expressed genes. We will analyze pedigrees constructed from resistant and susceptible individuals of ECB and WCR to identify genome regions linked to inheritance of Cry1Fa and Cry1Ab resistance in ECB, and Cry3Bb1resistance in WCR, using QTL mapping methods. Higher recombination among F8 or F10 progeny will allow fine mapping of QTL identified in the F2 backcross generation. All progeny will be genotyped with SNPs acquired using a genotyping-by-sequence approach (Elshire et al. 2011). 2b. Characterize races of corn pests, including ecology of races in sympatry. DE and IA will co-lead studies on characterization of races of corn pests, including ecology of races in sympatry. There is increasing evidence that ECB pheromone races (E and Z) differ behaviorally and ecologically in important, but ill-defined, ways, including resistance to Cry 1 proteins, host plant use, and phenology. DE will lead studies on races of fall armyworm and their differences among criteria similar to those mentioned for ECB. IA and DE will continue to provide molecular and pheromone analyses of ECB for cooperators, the most accurate ways to differentiate races, and will help transfer this technology to other investigators. IA, DE and PA will investigate population genetic differentiation and gene flow among E and Z pheromone race populations in PA, and its association with possible Cry1 protein resistance and ECB host races. 2c. Assess effects of seed blend refuge in Bt corn on biology, development, and behavior of multiple lepidopteran pest species. IA, NE, and DE dispersal and predispersal tasting survival rates will be measured in field plot trials using the approach employed by Davis and Onstad (2000). In brief, FAW egg masses will be placed in the whorl of vegetative-stage corn plants surrounded by uninfested plants. Living and dead larvae will be counted periodically using destructive sampling. Planting arrangements will include two peripheral non-Bt isoline plants surrounding one Bt (Cry1Ab, Cry1F, or Cry1Ab/Cry1F pyramid) plant or one non-Bt plant. Tests with a central Bt-corn plant will provide estimates of movement and survival of FAW after oviposition on Bt corn. Early samples will provide estimates of dispersal from infested plants, while later samples will assess larval survival. Comparisons to treatments with all non-Bt plants will reveal the relative effects of tasting Bt-corn tissue on larval dispersal and survival. Experiments will be conducted with reproductive-stage corn using the same design. 2d. Examine the potential role of microbial associates on important pest traits, including insecticide resistance, behaviors relevant to pest status, and insect-plant interactions. KY will lead a study comparing microbial communities across populations of corn insect pests and their natural enemies using next-generation sequencing technology. Following identification of microbes of potential interest, taxon-specific primers will be used in diagnostic screens to compare infection frequency of the microbe within and among populations of the host insect. Populations that differ in important phenotypic traits (e.g., insecticide resistance, virulence on resistant varieties) will be compared. IA will focus on comparing soil arthropod-associated microbes, including endosymbionts, across established long-term (>12 yr) crop rotation plots. 2e. Characterize dispersal of adult WCR and lepidopteran pests, and assess its implications for IPM and for resistance development, spread, and mitigation. IL and IA will lead studies to examine corn insect pest dispersal. Root injury data and emergence patterns will be used to describe the distribution of oviposition by WCR dispersing into Bt corn from refuge blocks. Analysis of WCR engaged in flight at 10m versus those flying within the corn canopy will reveal the proportion dispersing beyond the field and their respective physical and reproductive characteristics. A population genetics approach will be used to estimate long-distance dispersal among genetically differentiated WCR populations in its home range of eastern CO. The strategy will be to use large numbers of SNP genetic markers to estimate Wright's genetic neighborhood area, the radius of which constitutes a measure of the typical distance genes move per generation. WCR flight behavior and capacity will be compared across three Cry3Bb1-resistant and two susceptible strains using flight mills to determine the degree to which resistance affects dispersal. Three treatment groups of mated females will be tested: 1. Cry3Bb1-susceptible; 2. Cry3Bb1-resistant reared on Cry3Bb1 plants; and 3. Cry3Bb1-resistant reared on non-Bt plants. Several states will participate in a study led by FL, PA, and TX to map seasonal migration of fall armyworm into the central and eastern U.S. using a network of pheromone traps and molecular genetic markers. 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. NE and IA will coordinate target pest population collections from across Corn Belt and diagnostic bioassays will be conducted annually to assess susceptibility of target pest species (e.g. ECB and fall armyworm) using established methodology (Marcon et al. 1999, Marcon et al. 2000, Siegfried et al. 2007). Inheritance experiments will involve reciprocal crosses of resistant and susceptible parental populations to establish an F1 generation and dominance determined based on the response curve of the heterozygous individuals. Backcross of the F1 heterozygotes to one of the parental strains will be used to estimate the number of genetic factors that contribute to resistance. A variety of biochemical, molecular and genomic tools will be used to assess mechanisms of resistance (Coates et al. 2011, Crespo et al. 2011). 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. IA, IL, MN, NE, and Ontario will conduct field visits to identify suspected cases of Bt resistance. Fields will be visited in response to concerns by farmers and crop consultants of possible resistance to Bt corn. A gene check will be used to confirm the type of Bt corn planted in the field, roots will be sampled to evaluate feeding injury, and a sample of WCR collected to generate eggs for bioassays. Single-plant bioassay, following Gassmann et al. 2014, along with other bioassay methods, such as Nowatzki et. al (2008), will be applied to measure the level of resistance to various Bt events. NE and KS will make field collections of WCR in areas with pyrethroid use histories and/or reduced pyrethroid efficacy. Both adult diagnostic and dose response topical assays with pyrethroid active ingredients will be conducted to determine relative susceptibility level and geographic distribution of resistance. 3c. Work toward improving an artificial diet for WCR rearing and more sensitive bioassays of toxins. MO, Ontario, and FL will be working closely together to develop and evaluate diet formulations for WCR larvae. The MO team will also evaluate toxin overlays of each protein on the improved diet(s). A CO team will conduct behavioral evaluation of each diet and diet modification developed by other members of the team. Finally, a German contingent will evaluate changes in microbiota with the WCR associated with improved diets. 3d. Develop strategies to manage the ear-feeding pest complex and model implications for IRM and IPM. KS, TX, NE, MN will collaborate to evaluate the impact of cross-pollination of non-Bt refuge ears from pyramided Bt plants on the behavior, survivorship and fitness of fall armyworms and western bean cutworms in refuge in a bag (RIB) and strip refuges; determine the segregation and dosages of pyramided traits in ear-tip kernels of cross-pollinated non-Bt RIB and strip refuge plants; and evaluate the susceptibility of surviving adults’ progeny from cross-pollinated RIB and strip refuges to Bt toxins. SmartStax and Leptra pure stands and RIB plantings will be utilized. Field work will be conducted on cooperating producers’ field sites which will utilize natural infestations for TX, KS and NE and artificial infestations for MN. Fitness and survival of FAW and WBC will be followed to pupation in field experiments. Laboratory assays will be carried out in years two and three. 3e. Develop Helicoverpa armigera early detection and mitigation network. MN, TX, LA will coordinate expanded monitoring for H. armigera throughout the southern U.S. and across the Corn Belt. To facilitate, NE, MN, TX, and Brazil will conduct a workshop that will 1) teach morphological identification of H. armigera, 2) identify collaborators that will identify H. armigera using molecular techniques, 3) develop a light trap and pheromone trapping network, 4) assess current H. armigera management practices for possible use in the U.S., and 5) develop a research portfolio to address the impact and management of H. armigera in the U.S. 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. To more effectively evaluate the impacts of increased pyramiding and stacking of GE corn traits and evolving IRM guidelines on the risk of insect resistance and farmer productivity, the existing IRM models (Hurley et al. 2001, 2002; Onstad et al. 2002; Mitchell and Onstad 2005) will be extended to incorporate multiple insect targets with multiple modes of actions for each target. MN and WI will lead in developing the general IRM modeling framework. To regionalize the model, MN and WI will work with committee members to parameterize the yield loss models with regionally appropriate values based on regional data and pests. The model will incorporate regional variation in crop rotation, yield potential, and participation in farm programs and crop insurance. The model will be used to explore the extent to which limiting farmer access to coleopteran- or lepidopteran-only varieties of Bt corn affects the risk of resistance and agricultural productivity when the economic importance of each pest varies regionally. Obj. 4. Employ diverse delivery methods to disseminate information related to sustainable management of corn arthropod pests. 4a. Establish an NC-246 video library website with permanent high quality versions of IPM videos for open online access and download to computer and portable electronic devices. The library will be established under the system described in sub-objective 4b for clientele access online and download to computer and portable electronic devices. Video topics include, but are not limited to insect scouting videos, ‘How-to’ videos for pheromone or black light trap operation, IPM in organic systems, and emerging corn insect pest issue videos with clips from extension entomologists from multiple states and provinces. 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. KS will lead in producing and deploying a comprehensive, integrated system like MyFields.info for cost-effective prevention, early detection, rapid diagnosis, containment and mitigation of new and emerging corn pests that links all stakeholders. Stakeholder surveys will be used to define elements needed to sustain user interests in the system; a positive user-experience leads to increased use and rapid integration of relevant stakeholder inputs. Knowledge gaps in specific areas will be addressed in multiple geographic regions of the U.S. to allow uniform application of the system. This approach will blend smartphone technologies with traditional Extension activities and will lead to rapid detection and cost-effective management of invasive/emerging and common pests in corn. 4c. Develop an array of IPM and IRM distance education workshops. Committee members will continue to deliver live distance education programs to clientele utilizing electronic meeting software to present real time workshops state, region and province-wide. Programs will be archived for online access. Select workshops will also be placed on DVD and delivered to extension educators or other instructors and IPM field scout training programs nationally and internationally. This digital media could be played at extension meetings and other agribusiness training sessions and CEU credit could be given with prior approval through appropriate state or province-based certifying agencies. No internet access would be required for this approach (still an issue in some rural areas).
Measurement of Progress and Results
- Data (e.g. 2 refereed publications) documenting the ability of neonicotinoids to control secondary below-ground insect pests and an increased understanding of the effects of these compounds beyond the planted field,
- The assembled genome sequence of WCR and reference transcriptomes of WCR, ECB, and western bean cutworm. Identification of genes involved in Bt toxin and insecticide resistance in WCR, ECB, and western bean cutworm.
- Annual assessments of pest susceptibility provided to regulatory agencies and to sponsoring industry organizations, as well as refereed publications that document changes in susceptibility and additional studies related to inheritance and resistance mechanisms.
- 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.
- A comprehensive IPM system for cost-effective prevention, early detection, rapid diagnosis, and mitigation of new and emerging corn pests.
- Output 6: A refereed publication on estimates of intra- and inter-field movement of WCR adults and a detailed map of fall armyworm migration pathways and overwintering ranges in the U.S. Output 7: An improved artificial diet or diets will be developed that can be used for diet toxicity evaluations with all rootworm toxins. Output 8: Helicoverpa armigera early detection and mitigation workshop. Output 9: Data will on the magnitude and distribution of pyrethroid resistance in western corn rootworm populations. Output 10: Refereed publication that identifies microbes associated with corn insect pests and their natural enemies, and infection prevalence compared across insect populations and crop rotation treatments. Output 11: Refereed publication(s) characterizing genetic connectivity among and between pheromone race populations of ECB in Pennsylvania and on whether host plant races of ECB exist based on genetic evidence. Output 12: Refereed publication on the movement of key lepidopteran pests in a seed blend refuge. Output 13: Refereed publication on differential kernel feeding of the ear-feeding pest complex.
Outcomes or Projected Impacts
- U.S. corn producers and other stakeholders (e.g. regulatory bodies) will have the necessary information to make informed decisions on neonicotinoid seed treatment use and regulation.
- The assembled genome sequence of WCR and reference transcriptomes of several corn pests will serve as resources for the global research community for gene discovery, gene expression, and characterization of sequence variation.
- The identification of resistant strains and characterization of resistance among field populations will provide critical information to federal agencies that regulate the use of this technology and help ensure that the technology is used a sustainable manner. Bt resistance monitoring information is currently utilized by most of the major seed and biotechnology companies to support registrations of transgenic corn for both European corn borer.
- Improved IRM policies that reduce the risk of coleopteran or lepidopteran resistance and result in more resilient corn production.
- A comprehensive IPM system will transform how we extend information using mobile technologies and web-based social networks.
- Outcome/Impact 6: Results of behavior and genetic studies of WCR dispersal will help parameterize models of Bt-resistance evolution and mitigation with realistic data incorporating movement over all spatial scales. Outcome/Impact 7: Rearing of western corn rootworm all the way to beetle emergence will greatly improve efficiencies for a wide-variety of rootworm research. Outcome/Impact 8: The North and South American research community will be coordinated in their response to Helicoverpa armigera, a recently introduced pest. Outcome/Impact 9: Understanding the extent and severity of pyrethroid resistance by western corn rootworm will enable farmers to adjust their management practices accordingly. Outcome/Impact 10: Identification of viruses that infect rootworms may lead to development of vectors for delivery of rootworm gene-silencing RNA or novel biocontrol strategies. Outcome/Impact 11: Assortative mating among ECB races within geographically isolated populations could accelerate development of resistance to Bt corn, and results will help guide priorities for resistance monitoring. Outcome/Impact 12: The understanding of pest movement in a seed blend refuge strategy will allow regulators to assess the appropriate use of this refuge strategy. Outcome/Impact 13: An understanding of the kernel feeding behavior of the ear-feeding pest complex will help resistance modeling efforts for IRM and IPM of these pests.
Milestones(0): duration and timetable: Many objectives are continuing and will continue throughout the project life. Time to significant output (e.g. publication, diet, etc.) is indicated by uppercase X, and continued research indicated in lowercase x. ____________________YEARS________________________ ______2016 _____2017______2018______2019______2020__ Obj 1 1a. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 1b. XXXXXXXXXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxxxxxxxxxx Obj 2 2a. XXXXXXXXXXXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxxxxxxx 2b. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXxxxxxxxxxxx 2c. XXXXXXXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxxxxxx 2d. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxx 2e. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXxxxxx Obj 3 3a. XXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 3b. XXXXXXXXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxxxxxxxxxxx 3c. XXXXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxx 3d. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXxxxxxxxxxxxx 3e. XXXXXXXXXXXXXXXXXXXXXX 3f. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 3g. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Obj 4 4a. XXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 4b. XXXXXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 4c. XXXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx __________________________________________________________________________
Projected ParticipationView Appendix E: Participation
Members of NC-205 and NCCC46 are involved in field demonstrations and outreach efforts related to the sustainable management of corn arthropod pests. In general, they recommend IPM approaches that exploit as many strategies for suppressing pest levels as possible to avoid growers' reliance on any one practice or tactic. Many committee members interact regularly with farmers, radio broadcasters, government agencies, and other Ag professionals regarding IPM and IRM. They also interact with directors of state corn grower association boards to communicate science-based information on biotechnology issues. In addition to helping farmers and the public understand IRM programs, committee members with extension appointments will provide guidance about how transgenic crops and IRM programs fit into a larger field corn IPM program. Specifically, how growers should make informed decisions about the management of corn insect pests.
Traditional and electronic extension meetings and educational programs will be held with producers, industry, consultants, and regulators to discuss findings and share information and ideas to enhance policy and regulatory decisions compatible with the economic, environmental, health and social needs of both the agricultural and non-agricultural communities. Feedback from growers will be used to help direct research activities of the committee. Newsletters, traditional extension materials, Web pages, Blogs and other social media, videos, interactive CD training modules, scientific publications, surveys and focus groups, and position statements will be used to disseminate information to the agricultural and public sectors. Objective 4 further details our outreach efforts that employ electronic delivery methods. Activities will focus on expanding the land-grant university research and Extension presence and leadership role in the electronic media arena to provide unbiased science-based IPM and IRM decision support to clientele.
The project will be administered by a Technical Committee consisting of all participants of the project, and all are eligible for office, regardless of sponsoring agency affiliation or the number of members per SAES. An Executive Committee will consist of a Chair, Secretary (each serving 1-year terms), and the Administrative Advisor. An annual meeting of the full Technical Committee will be held to summarize and critically evaluate progress, analyze results, and plan future activities, reports, and publications. The Executive Committee Chair, in consultation with the Technical Committee and with the concurrence of the Administrative Advisor notifies the Technical Committee members of the time and place of meetings, prepares the agenda, and presides at meetings of the full Technical Committee and Executive Committee. The Administrative Advisor authorizes the annual meeting 90-120 days in advance. Two standing subcommittees will operate under the Executive Committee, each with its own Chair and Secretary. One subcommittee will focus on underground pests of corn, reflecting the historical research emphasis of NCCC46 and its predecessors on corn rootworms. This subcommittee's Chair will be responsible for setting the agenda and presiding over the portion of the annual meeting devoted to state reports on below-ground corn insects, and the subcommittee's Secretary will take minutes. The other subcommittee will focus on above-ground pests of corn, reflecting the historical research emphasis of NC205 and its predecessors on corn borers and other lepidopterans. This subcommittee's Chair will be responsible for setting the agenda and presiding over the portion of the annual meeting devoted to state reports on above-ground corn insects, and the subcommittee's Secretary will take minutes. Membership in either subcommittee will be open to any project participant, each of whom may affiliate with one or both or neither, based on self-identified interests. The Chair and Secretary of each subcommittee will be elected annually by participants on that subcommittee, and each will serve a 1-year term culminating at the close of the annual meeting. The Subcommittee Secretary will rotate into the Subcommittee Chair position after the first year. Subcommittee Chairs will rotate (in alternating years) into the Executive Committee Secretary position followed one year later by rotating into the Executive Committee Chair position. This will ensure alternating representation on the Executive Committee of both sets of historic research interest groups. Therefore, election as Secretary to one of the subcommittees implies a 4-year commitment as an officer, culminating in the 4th year as Chair of the Executive Committee. The Executive Committee will conduct full-committee business during and between annual meetings (e.g. annual reports, NIMSS entries, project rewrites). It also will be responsible for organizing, setting the agenda, and presiding over an annual Open Meeting with Industry, EPA, and other invited guests, which will be scheduled as part of the regular annual Technical Committee meeting.
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