Duration: 10/01/2010 to 09/30/2015

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Statement of Issues and Justification

Over 80 million acres of field corn (Zea mays) and 600,000 acres of sweet corn, worth about $40 billion and $1 billion respectively, are grown in the U.S. each year. The European corn borer (ECB), Ostrinia nubilalis, accounts for over $1.85 billion in control costs and grain losses annually. In 2006, 88% of the fresh market sweet corn acreage was treated with one or more insecticide applications for a total of 605,000 lbs of insecticides applied. ECB also attacks many other crops, such as sorghum, small grains, potatoes, beans, tomatoes, and peppers. The southwestern corn borer, Diatraea grandiosella, causes about $1 million in damage in the Western High Plains (Morrison et al. 1977). Recently, the sugarcane borer, Diatraea saccharalis, has emerged as an important corn pest in the southern U.S. Other significant stalk-boring pests include the common stalk borer, Papaipema nebris, hop vine borer, Hydraecia immanis, and potato stem borer, Hydraecia micacea.

Since 1950, previous committees have focused on ECB and other stalk-boring lepidopteran corn pests. In addition to stalk borers, we propose to address the other lepidopteran corn pests, which include those that feed on corn leaves and ears. This is a natural progression for the committee, as these pests are increasing in economic importance. Corn earworm, Helicoverpa zea, and fall armyworm, Spodoptera frugiperda, consume corn leaves, tassels, silk and kernels. In the southeastern U.S., losses attributed to corn earworm in field corn range from 1.5-16.7%, and sweet corn losses can be as high as 50% (Wiseman 1999). Black cutworm, Agrotis ipsilon, is the most damaging of the cutworm complex in the Corn Belt. Stand loss over 25% and yield losses of about 2,900 kg/ha are not unusual (Showers et al. 1983, Showers 1999). Western bean cutworm, Striacosta albicosta, increasingly is a pest of corn ears across the north central region.

Since the commercial release of Bacillus thuringiensis (Bt) transgenic corn in 1996, a revolution in corn insect pest management has occurred. This revolution is rapidly moving corn pest management away from synthetic pesticides to plant-based toxin delivery systems. The use of Bt sweet corn varieties has been less dramatic, but is important because of its higher insecticide inputs and direct use as human food. This technology often eliminates the need to store and handle insecticides and it increases the ease of planting and pest control.

Seed companies continue to develop genetically-modified (GM) crops for pest protection. The first GM corn produced was resistant to ECB and a few other lepidopteran pests. New GM corn hybrids have resistance to a broader range of lepidopteran pests, and some have resistance to coleopteran pests. The most current GM hybrids have two genes targeting lepidopteran pests and two genes targeting coleopteran pests. These changes in corn technology have caused major changes in the agricultural community and identified major knowledge gaps, increasing the need to reevaluate knowledge about ECB and other corn pests. For example, an insect resistance management (IRM) program was never a legal requirement for any pest management technology until the introduction of Bt corn. Publicity and attention to scientific advisors led the EPA to require IRM programs on farms where Bt corn hybrids are used; consequently, the concept that resistance could be prevented went from a theory to an experiment in-progress.

Bt corn acreage in the U.S. has increased from 8% in 1997 to 63% in 2009. Corn hybrids that have multiple genes targeting both ECB and corn rootworm could further increase the percentage of acres planted to Bt corn for ECB because in some regions corn rootworm is considered a more important economic pest than ECB. As the level of adoption increases, the potential for resistance evolution increases. Research conducted by this committee was used to develop models predicting the rates of resistance evolution and to investigate the role of refuge in preventing resistance. This led to the IRM approach that utilized a 20% refuge; however, as GM technology has evolved, so has IRM. Recently deployed GM corn hybrids utilize multiple genes that target ECB. The IRM plan for these hybrids requires a smaller refuge of at least 5% (in non-cotton production regions), and seed mixtures (Bt and non-BT) are being considered for future GM corn. The models used to allow for these IRM modifications were constructed using the best information available, but a number of assumptions had to be made. These assumptions need to be tested and research conducted to move them from assumptions to quantified variables. In addition to addressing these information gaps, information is needed on the economics of this evolving technology. Eliminating these information gaps forms the basis for several objectives of the project. The long-term goal of our research is to develop sustainable ways to manage lepidopteran corn pests. This is a high regional priority, and in the context of demonstrating sustainable practices, it also is an important national priority.

Implications of GM corn in the landscape and pest management. Insect pests commonly have developed resistance to conventional insecticides when they are overused (Georghiou 1986), and scientists and growers are concerned that overuse of Bt corn could produce pests resistant to Bt toxins (e.g. Tabashnik 1994, Gould 1998). One of the biggest hindrances to providing accurate assessments of resistance risk is the lack of resistant colonies that are able to survive on transgenic plants. Such colonies would provide the opportunity to validate existing IRM strategies, identify resistance-associated genes, and develop molecular markers that are diagnostic for resistance. Recently, an ECB colony has been selected for that exhibits high levels of resistance to Cry1F and increased ability to survive on Cry1F corn tissues (Alves et al. 2006). Likewise, a colony of sugarcane borer was developed with resistance to Cry1Ab corn (Huang et al. 2009). Research on such colonies can aid in answering questions pertaining to the risk of Bt resistance development, help characterize genetic markers assay of Bt resistance, and help in development of diagnostic assays for resistance. The research can directly assist in the formulation of IRM strategies for GM crops by providing biological data that has previously been unavailable.

Because of the widespread use of Bt corn, there exists the potential for area-wide suppression of ECB populations, and the evidence for this is building (Hellmich 2006, Hutchison et al. 2007, Storer et al. 2008). Assessments of the benefits of Bt corn have usually focused on agronomics directly related to the crop (e.g. Marra and Piggott 2006), but by suppressing ECB populations, there may be far reaching economic, environmental, and human health benefits to not only users of Bt corn, but to non-Bt corn growers and others who grow crops for which ECB is a pest. It is therefore important to quantify the landscape-scale suppression of ECB associated with widespread Bt corn use and to estimate the farm and market level economic, environmental, and health benefits resulting from this suppression.

Another issue has been the need to more fully understand the impacts of GM technologies on non-target organisms. Never before in the history of pest management has there been as much pressure placed on the scientific community by the general public to understand the ecological impacts of new pest management tactics. Although numerous experiments have indicated that toxins produced by Bt corn have few if any significant negative effects on non-target organisms, debate continues in the scientific community (e.g. Romeis et al. 2008, Lovel et al. 2009). Members of this committee have contributed knowledge about the non-target impacts of GM crops, but there is not yet an accepted way of judging how much and to what extent change in biodiversity is important. Research to help understand how ecosystems function, and how new practices are changing the biodiversity in and near cornfields, is needed.

Adaption of IPM systems for changing pest complexes. Since the advent of Bt corn, there has been a shift in the corn pest complex in many regions. For example, the western bean cutworm historically has been a pest of corn in the western Great Plains (Keaster 1999). Since 2000, western bean cutworms have been increasing in abundance east of Nebraska, (ORourke and Hutchinson 2000, DiFonzo and Hammond 2008) and are now found as far east as Ohio (DiFonzo and Hammond 2008). Reasons for the recent range expansion are not known, but several possibilities are proposed, such as increased use of reduced tillage, milder winter temperatures, reduced precipitation, reduced use of foliar insecticides, and suppression of competitors (Catangui and Berg 2006). Yield losses of 30-40% have been reported, and a nominal threshold of 8% of plants infested with egg masses or small larvae has been used in its original range (e.g. Seymour et al. 2004). More comprehensive economic thresholds and management recommendations are needed across its current range, and there is increasing interest in monitoring procedures.

Climate change has important implications for corn IPM. Warmer temperatures and changing precipitation patterns may be in part responsible for the range expansion of western bean cutworm, but also for a host of corn pests. Range expansion of four major corn pests, including corn earworm and ECB, has been predicted by analyzing pest overwintering thresholds and degree-day requirements along with climate change projections (Diffenbaugh et al. 2008). These range expansions could have significant economic impacts via increased yield loss and management costs. Corn IPM will necessarily have to adapt to these changing conditions.

Changes in disease incidence also are expected with changes in pest complex. Corn diseases cause up to 15% yield loss in the U.S. (White and Carson 1999), costing over $3 billion annually. Fungal infection of ears can reduce quality of the grain, but also cause disease in humans and livestock that consume contaminated grain or its products. The FDA has established action levels that regulate concentrations of aflatoxins as low as 20 parts per billion in livestock feed (van Egmond, 1991). Incidence of fungal infection and concentrations of mycotoxins is increased in plants injured by insects. For example, grain produced by plants infested with southwestern corn borer had higher concentrations of aflatoxin than uninfested plants (Windham et al. 1999). Research conducted with Bt transgenic corn and their near-isogenic non-transgenic counterparts indicated a decrease in ear rot severity and mycotoxin concentrations in the Bt corn; however, it is not known if this relationship will hold true for pests that are only partially controlled by current Bt corn hybrids.

Ecology, evolution, genetics, and behavior. ECB is not only a major pest of corn, but is also a model species for lepidopteran genetics (Willet and Harrison 1999, Ferré and Van Rie 2002, Dopman et al. 2005), speciation (Roelofs et al. 1985, Linn et al. 1997, Dopman et al. 2004), insect/host-plant interactions (Ponsard et al. 2004, Calcagno et al. 2007, O'Rourke et al. 2009), and IRM (Ives and Andow 2002, Shelton et al. 2002, Qiao et al. 2008). Clarification of population structure and genetics is necessary to model the risk of resistance development and to design IRM strategies. More information for this species is needed on geographic patterns of genetic variation, voltinism, pheromone blend, sensitivity to Bt, and the influence of host plants to develop models of gene flow. Also, little is known of the population structure and genetics of other corn Lepidoptera. Acquiring such information will increase our understanding of the mechanisms of resistance, genetic basis for resistance, status of cross-resistance, and stability of resistance.

The advent of new DNA sequencing technologies is bringing the potential for genomics research within range of even nonmodel organisms. Genomics research on lepidopteran pests will provide opportunities to probe the genetic basis of many phenomena, including insecticide resistance (Alves et al. 2006), behaviors relevant to pest status, and insect-plant interactions. Construction of EST libraries will facilitate development of genetic markers necessary for population genetics studies and enhance development of linkage maps and QTL mapping for ECB (Coates et al. 2008, Khajuria et al. 2009). The coming explosion of sequence data will require coordinated development and maintenance of genomics databases for data presentation, mining, and annotation.

Despite nearly a century of research on ECB, spatial and temporal aspects of ECB movement and mating behavior have proven difficult to characterize. A clear understanding of mating behavior is important for modeling and estimating the likelihood of resistance developing in ECB to Bt corn (Guse et al. 2002), estimating gene flow, and implementing IRM. Analyses of gene flow indicate a substantial exchange of ECB migrants between locations separated by 1000 km or more (Bourguet et al. 2000, Malausa et al. 2007, Krumm et al. 2008, Kim et al. 2009). Such high gene flow implies that resistance to Bt corn will be slow to develop, but if it does develop, it will rapidly spread. However, it is not clear if these results can be extrapolated outside the Corn Belt. The situation in the eastern U.S. is further complicated by a number of sympatric races of ECB. A better understanding of the behavior and ecology of the races is critical to effective IPM and IRM of ECB.

Enhancing natural control is the first line of protection in IPM. Even though the biology of most of the natural enemies associated with corn has been described, the effects and value of these natural enemies in the landscape is not well understood. Information gaps include understanding patterns of variation in natural enemy communities in a corn and soybean agroecosystems. Gaps extend to quantifying the role of natural enemies in resistance evolution, improving the use of augmentative biological control, and characterizing the economic value of natural enemies (Musser et al. 2006). Scientists studying the impact of Bt crops on natural enemies generally conclude that there is little direct effect from the Bt itself (Marvier et al. 2007, Dhillon and Sharma 2009); however, the dynamics associated with how the change in pest populations in Bt corn affects natural enemies need to be studied.

As previously noted, the western bean cutworm has been expanding its range, and little is known about the causal factors. Two potentially important factors are pathogenic microsporidia that infect it (Su 1976, Dorhout 2007) and its host plants (Blickenstaff and Jolley 1982). Research and population genetics analyses are necessary to investigate the interactions between genetic diversity, range expansion, gene flow, microsporidian infection and host plant usage. Knowledge is needed that will provide a scientific foundation to develop innovative ways to manage this pest. Furthermore, this is a rare opportunity to study a biological invasion as it happens and it will serve as a model for invasive species.

For philosophical or economic reasons, not all growers will adopt Bt corn, and effective management options are needed. For example, little research has been conducted on managing ECB in organic corn (Delate and Cambardella 2004, Evering 1985). Organic corn production has been steadily increasing, which is raising the need to conduct research on basic biology of corn pests in this system.

Electronic delivery of information. The audience for the results of this project is growing. Not only does it comprise farmers and other ag-professionals, but also policymakers, researchers, high school and university educators, concerned citizens, and their expectations are greater than ever before. It is critical that the results be packaged as unbiased information for these agricultural and public sectors. The days of publishing hard copy documents and then simply distributing them or posting them online are over. While traditional information dissemination is still needed, stakeholders are expecting that information be provided in various formats, be timely, immediately accessible from their home or office, interactive, and provide real-time data.

In 2010 an updated edition of this committees publication, NCR-327 European Corn Borer Ecology and Management will be published. An online version could provide a platform for an expanded, interactive version with economic threshold calculators, scouting video clips, links to pest trap networks, and other pertinent publications and educational material. It also could provide the opportunity to obtain important feedback from stakeholders. For example, online surveys could assess growers needs and opinions concerning corn IPM and adoption of IRM practices. This data could then be used to balance logistical and economic expectations for effective corn pest management with the desire to maintain long-term durability of new technologies. As the body of corn Lepidoptera biology, ecology, IPM and IRM knowledge grows in both volume and complexity, it is critical that stakeholders have a complete, easily accessible source of scientifically-based, unbiased information that the NC-205 committee can provide.

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 effective technology transfer is appropriate and necessary. As shown above, geography plays an important role in how the 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, particularly GM technologies. Controversy about the effect of GM 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 GM crops. Answers to questions regarding Bt-corn should help focus the public's perception of this technology and where benefits are clearly demonstrated, and allow growers to gain the pest control advantages provided by this and future technologies.

These multi-state plans will 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, and evolution. Our work will continue to provide scientifically-based assessments essential to the policy decision-making process and should help to increase the public's acceptance of these technologies and to identify potential negative impacts that need further investigation. Our work also will continue to lead to more sustainable pest management systems for lepidopteran corn pests. We also view it as our responsibility to provide unbiased, scientifically-based information that fosters subsequent investment in promising novel approaches to pest management. There is ample evidence that the NC-205 research group has 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 44 active projects related to corn Lepidoptera or corn insects. Of these, 19 are directly associated with NC-205 and four projects are led by NC-205 collaborators. Of the remaining 21 projects, the corn insect pests under study are often from orders other than Lepidoptera, such as Coleoptera. Eight are broad and include a few corn insect pests as components of a general IPM or pest management project covering several crops. The 13 others cover a variety of subjects, such as organic crop production, stored product pests, or biocontrol of insects, and again often focus on insects in other orders or are narrow in scope with respect to a specific corn pest.

Several USDA-ARS Units conduct research on lepidopteran pests of corn, including units at Tifton, GA (Crop Genetics and Breeding Research Unit), Stoneville, MS (Southern Insect Management Research Unit), Manhattan, KS (Biological 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 corn pests, and several of its research scientists are members of NC-205.

A NIMSS search indicates four active regional projects that involve the biological control of insects: W-2185 Biological Control in Pest Management Systems in Plants; S-1034 Biological Control of Arthropod Pests and Weeds; NE-1032 Biological Control of Arthropod Pests and Weeds; and NCERA-125 Biological Control of Arthropod and Weeds. 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 will continue to deal specifically with natural enemies of stalk-boring Lepidoptera. Our committee has established cooperative interactions with these biological control committees and we will continue to coordinate efforts with other regional projects investigating biological control. Another regional project that deals in part with corn insect pests, NECC-1008 Improving Sweet Corn: Genetics and Management, has little overlap with NC-205.

NCCC-46 is a multi-state committee focused on the biology and control of corn rootworms. We have held overlapping meetings with this committee, industry, and other stakeholder (e.g. EPA) for over a decade to share ideas in the rapidly evolving area of transgenic corn. Because stacked hybrids now contain genes that target both corn Lepidoptera and corn rootworm, it will be essential to continue to coordinate activities with NCCC-46 members. Growers will need consistent recommendations from both groups. Several members of NC-205 attend NCCC-46 meetings regularly, so effective coordination is already the norm.

With the various sustainable agriculture efforts, based largely on the principles of IPM, there are a few projects with one or two corn insects; however, we know of no other research efforts engaged in a regionally coordinated project that focuses on the ecology, evolution, genetics, behavior, and management of corn Lepidoptera.

Monitoring techniques developed at the University of Nebraska for detecting Bt resistance in the European corn borer (ECB), Ostrinia nubilalis, are currently used in support of an annual resistance monitoring program for the major Bt toxins that are deployed in transgenic Bt corn varieties targeting the ECB. This effort provides a means for early detection of Bt resistance and is an essential component of Bt resistance management programs (Siegfried et al. 2007). Based on the combined results of concentration-mortality assays and diagnostic bioassays employing the Cry1Ab and Cry1F protein from Bt, there has not been a detectable change in susceptibility among ECB populations in the USA resulting from the introduction of transgenic corn. The methods used are sufficiently sensitive to detect a low frequency of insects with incomplete resistance, indicating that if resistance were evolving in the field, it is likely to have been detected (Crespo et al.2009). Perhaps the biggest source of variation in these assays has been inconsistent sources of toxins. Significant effort has been invested in developing methods for quantification of Bt toxins (Crespo et al. 2008) in order to standardize the toxin concentrations and provide increased consistency in our monitoring efforts.

Techniques are continuing to be developed for identification of Bt receptors in the gut of ECB and potential modifications that may result from resistance development. A 220-kDa protein has been identified from ECB midguts as a cadherin-like molecule, which binds Cry1Ab toxin and confers susceptibility to fall armyworm, Spodoptera frugiperda, (SF9) cells transfected with the cadherin gene (Flannagan et al. 2005). These results in combination suggest strongly that a cadherin-like protein acts as receptor and is involved with Cry1Ab toxicity. Comparison of cadherin expression in a Cry1Ab resistant ECB strain identified by laboratory selection (Chefaux et al. 2001, Siqueira et al. 2004) indicated that resistance was associated with altered receptor binding although cadherin gene expression was similar in both the resistant and susceptible strains and suggests a more complex resistant mechanism (Siqueira et al. 2006). Several major mutations in the ECB cadherin that introduce premature termination codons and/or large deletions have been associated with Cry1AB resistance (Bel et al. 2009). However their contribution to resistance is still uncertain because the presence of major mutations was drastically reduced in individuals that survived exposure to high Cry1Ab concentrations. Previous inheritance experiments with the resistant strain (Alves et al. 2006) indicated the involvement of more than one genetic locus and and support the complex nature of the resistance mechanism.

Efforts to develop Bt resistant strains of ECB and to characterize their resistance have resulted in a number of important findings related to potential evolution of resistance in field populations. A strain of ECB has recently been identified through laboratory selection that exhibits high levels of resistance (>3,000-fold) to the Cry1F Bt protein (Pereira et al. 2008a,b). Importantly, this strain is the first that we know of that exhibits the ability to develop on Bt expressing corn plants. Because the resistance is almost completely recessive and appears to be conferred by a single genetic locus (Pereira et al. 2008b), current resistance management recommendations that involve the high dose/refuge approach appear to be justified. Importantly, however, the resistance gene does not appear to be associated with major fitness deficits and suggests that it may be maintained at relatively high frequencies among field populations (Pereira et al. 2009).

Next-generation DNA sequencing technologies are rapidly bringing the potential for genomics research, including whole genome sequencing, within range (Miller et al., in press). Development of linkage maps and QTL mapping for ECB is progressing (Coates et al. 2008, Khajuria et al. 2009).

To safeguard Bt technology against the evolution of resistance in target pests (Tabashnik et al. 2003, 2008; Qiao et al. 2008; Tyutyunov et al. 2008), substantial efforts are being made to delay the development of resistance through insect resistance management (IRM) (Bourguet et al. 2005, Sivasupramaniam et al. 2007). Not all growers will adopt Bt corn for various philosophical or economic reasons, and effective management options are needed. For example, little research has been conducted on managing ECB in organic corn production systems (Delate and Cambardella 2004, Evering 1985). Organic corn production has been steadily increasing, which increases the need for research on basic biology of corn pests that addresses issues in this system. Effective strategies for both IPM and IRM for Lepidoptera require a thorough understanding of population dynamics, which in turn requires an understanding of adult movement and consequent gene flow over space and time. Recent work indicates that there is substantial movement of ECB between locations separated by 1000 km or more (Bourguet et al. 2000, Malausa et al. 2007, Krumm et al. 2008, Kim et al. 2009), implying that resistance to Bt corn will be slow to develop, but will rapidly spread if or when it does. Corn acreage in the eastern U.S., is less than in the Midwest, but is still substantial (Dillehay et al. 2004). Resistance is most likely to evolve in small populations with low immigration rates (Taylor et al. 1983, Caprio and Tabashnik 1992, Lenormand and Raymond 1998), a condition that could be favored by the more broken landscape of the eastern U.S., with topographical features creating potential barriers to ECB dispersal (Sorenson et al. 2005).

The situation in the eastern U.S. is further complicated by a number of sympatric races of ECB. Z- and E-races are partially isolated by different dominant racemic isomers in their sex pheromone communication systems (Cardé et al. 1978). The Z-race is widespread east of the Rocky Mountains, but the E-race is restricted in range to the eastern U.S. (Sorenson et al. 2005, O'Rourke et al. 2009). Complexed with pheromone race are voltinism races (Glover et al. 1991, Showers 1993), denoted as B for bivoltine or U for univoltine. Combinations of pheromone and voltinism races results in three types of partially reproductively isolated races, designated by convention as BZ, UZ, and BE (Roelofs et al. 1985, Showers 1993). Most research has been performed on BZ moths, the most common and widespread race in North America, and little is known about differences in dispersal and behavior among the races. Finally, there is the possibility of sympatric host races of ECB, especially in the BE race (Sorenson et al. 2005, O'Rourke et al. 2009). A much better understanding of the behavior and ecology of the races and their hybrids is critical to effective IPM and IRM of this insect.

The western bean cutworm (WBC), Striacosta albicosta, is a corn pest that has been expanding its range of activity for a little over a decade. In 1999, WBC were found feeding in experimental plots of corn throughout southwestern Minnesota (O'Rourke and Hutchison 2000). Though present in South Dakota for many years (Fauske 1982), it did not cause economic damage there until 2000 (Catangui and Berg 2004). In 2001, widespread damage to corn crops occurred throughout western Iowa (Rice 2002), and was reported for the first time in Illinois and Missouri in 2004 (Dorhout and Rice 2004). The species continues to spread eastward and is now found in Wisconsin, Indiana, Michigan, Ohio, (Rice and Dorhout 2006, Pope 2007, DiFonzo and Hammond 2008) and Ontario (Baute, personal communication). At present, little is known about the factors that initiated and sustain this range expansion, although population genetic evidence indicates it was not due to a sudden breach of a topographical barrier (Miller et al. 2009). Research has been initiated across the current WBC range on possible reasons why its range has expanded and on an array of WBC biological, ecological, and behavioral factors that will be used to develop a comprehensive IPM program for this pest.

Introduction of Bt crops has changed the agro-ecosystem where the natural enemies have traditionally played an important part. Although recent work generally indicates there is little direct effect from the Bt itself on natural enemies (e.g. Marvier et al. 2007, Dhillon and Sharma 2009), others disagree (Lovei et al. 2009) and the effects and value of natural enemies in various resistance management refuges and corn cropping systems is not well enough understood to fully know the role they play. Key information gaps include understanding patterns of variation in natural enemy communities associated with landscapes dominated by corn and soybeans intermingled with resistance management refuges (White and Andow 2005). Gaps extend to adequately quantifying the role of natural enemies in resistance management, improving the use of augmentative biological control agents in crop refuges, and characterizing the economic value of natural enemies in cropping systems (Musser et al. 2006). It is possible that that natural enemy abundance and diversity in corn may be influenced by reduction in target pest populations due to wide use of transgenic crops; and some predators and host-specific parasitoids may have such a limited food source that only those with superior host-finding behavior will persist in landscapes dominated by Bt corn.

Novel F2 and F1 screening methods have been developed at the Corn and Small Grain Insect Research Laboratory at the LSU Ag Center (Huang et al. 2007a), and significant progress has been made examining the presence of Bt resistance in sugarcane borer, Diatraea saccharalis, (Huang et al. 2007 b,c,d; Huang et al. 2008; Huang et al. 2009). More than 2000 sugarcane borer from Louisiana and Texas were examined for Bt resistance alleles during 2004-2007. Major resistance alleles that allowed resistant insects to complete larval development on Bt corn plants were detected in three Louisiana populations. Monitoring results indicate that Bt resistance allele frequency in sugarcane borer populations in Louisiana and Texas may meet the rare resistance allele requirement of the high dose refuge IRM strategy for Bt corn. However, continuous monitoring of Bt resistance in sugarcane borer is necessary to maintain the sustainability of Bt corn for corn borer management in the mid-southern region of the U.S. The Bt resistance in the sugarcane borer populations detected in this study is the first major resistance allele to commercial Bt corn hybrids in any corn stalk borer species worldwide. This resistant strain has value in understanding the mechanisms of Bt resistance in sugarcane borer and other corn borer species.

Objectives

1. Investigate the relationship between transgenic maize and the agricultural environment.
   
2. Adapt IPM systems for the changing pest complexes in maize.
   
3. Investigate ecology, evolution, genetics, and behavior of pest Lepidoptera.
   
4. Employ electronic delivery methods to disseminate information related to sustainable management of Lepidopteran pests.
   

Methods

Objective 1. Investigate the relationship between transgenic maize and the agricultural environment. IA, NE, KS, ONT, MN, OH, DE, MD, GA, IL, WI, TX.

1a. Studies are underway in IA, IL and NE to test the feasibility of using non-Bt corn seed blended with Bt transgenic seed as a source of refuge. This research focuses on the genetics of interplant movement of European corn borer (ECB) larvae. Susceptible and resistant colonies of ECB will be tested on non-Bt, single-toxin and pyramided corn. Initially bioassays with artificial diet will be used to assess how resistance alleles impact tasting survival by switching larvae from diets with Bt tissues to diets without Bt tissues. Results of these laboratory trials will guide selection of the most appropriate treatments for subsequent testing in semi-field experiments. These trials will examine how resistance alleles from ECB colonies impact dispersal and tasting survival of larvae after exposure to various Bt toxins. Dispersal and tasting survival are key parameters identified by models for strip and seed mix refuges. The information from these experiments will be incorporated into existing IRM models.

1b. Research will be conducted in NE, IA, IL to compare the production of ECB in mixed refuge and block refuge plantings. One of the assumptions of using blended seed is that in fields of equal size the numbers of ECB produced in a field with mixed Bt and non-Bt plants will be comparable or greater than the number produced in a field with structured refuge. If the number produced in a mixed-refuge field is substantially lower than the blended-seed strategy would be compromised. Test plots will be established with blended-seed and block refuges in several states that will directly compare the production of first and second generation ECB.

1c. Researchers in NE, IA and MN will continue to improve the efficiency of monitoring for ECB resistance to Bt corn. Established colonies of ECB with resistance to Cry1Ab and Cry1F will be used to investigate mechanisms of resistance and cross-resistance. IA and NE will lead efforts to use molecular markers and linkage maps to identify regions of the ECB genome associated with Bt-resistance traits. The marker-trait associations will be used to extend characterizations of the genetic architecture of Cry1Ab resistance found in classical genetic studies of both resistant and susceptible colonies of ECB. The final product will be isolating and examining what expressed resistance genes are actually linked to our markers. Knowledge obtained from these studies will be applied to cross resistance issues that will be important to identify compatible proteins used in stacked gene products. The identification of specific molecular markers that are associated with resistance will allow development of high-throughput screening techniques to increase the sensitivity of resistance detection. Traditional concentration-response and diagnostic concentration bioassays will continue to be used for detecting both Cry1Ab and Cry1F resistance in ECB populations throughout the Corn Belt. Baseline susceptibility will be determined for new toxins that may be deployed.

1d. MN, WC, MD, IA, IL and NE will collaborate with an economist from WI to document and measure the off-site community effects of Bt field corn use on ECB populations and assess the environmental and productivity benefits in terms of reduced insecticide use and environmental risks in vegetable crops (e.g. sweet corn) that rely heavily on insecticides to control ECB. Also, insect trapping records will be evaluated to determine if similar suppression has occurred with corn earworm and fall armyworm. Off-site suppression will be determined from analyses of new and existing databases, with metrics reflecting changes in ECB populations during periods before and after introduction of Bt corn. Various metrics will be recorded in sentinel plots of untreated sweet corn and other vegetables in regions with different rates of Bt corn adoption. To estimate the yield benefits for sweet corn and other vegetables due to ECB suppression, a hierarchical model will be developed to link measures of ECB population density to crop damage and yield loss for both the pre- and post-Bt periods. Reductions in insecticide use will be based on ECB moth flight data comparing probabilities and frequencies that moth flight numbers exceed action thresholds for pre- and post-Bt corn years. Separate analyses will be performed for each state/region with varying rates of Bt corn use. We will measure environmental impacts using the environmental impact quotient and the more recent multi-attribute toxicity factor.

Objective 2. Adapt IPM systems for the changing pest complexes in maize. NE, KS, ONT, GA, WI, OH, IA, MI, PA, MD.

2a. Field studies will be conducted in NE and other participating states/provinces to establish yield loss-density relationships and economic injury levels for western bean cutworm (WBC) in field corn across its geographic range. Depending on location, a non-Bt or a Bt transgenic corn hybrid expressing the Cry1Ab toxin adapted to the specific region will be selected for infestation. The Cry1Ab toxin controls ECB and suppresses corn earworms, but is not active against WBC and minimizes confounding effects of having multiple lepidopterous insects influencing yield. Egg masses will be introduced into each plot at varying levels. At dent stage, a subsample will be taken to estimate number of larvae per plot. Yield loss per insect, one of the factors necessary to calculate an economic injury level, will be determined.

2b. Quantify the relationship between WBC damage levels to grain, grain molds, and aflatoxin production. Ear rot incidence and severity will be determined in NE and other states/provinces across the WBC range. Grain from corn ears harvested in the field studies in objective 1a will be evaluated using the methodology similar to Munkvold et al. (1999). Aflatoxin and fumonisin concentrations will be measured on a subsample of the grain from each plot following harvest. Grain will be processed and mycotoxins extracted according to the ELISA-based mycotoxin kit instructions from Neogen (Woloshuk 2001). Concentration of aflatoxin, fumonisin, ear rot incidence and severity will be related to severity of WBC injury, location and year.

2c. WBC flight phenology, as determined by pheromone and black light trap, will be compared with corn phenology and oviposition in field corn and correlated with degree-day accumulation. In NE and at locations in other states/provinces, black light traps will be used to monitor for WBC moth flight. Pheromone traps will be established on the edges of nearby cornfields using commercially available WBC pheromone. Egg sampling and corn staging will be initiated when the first WBC moth is caught in black light or pheromone traps. Egg masses will be sampled from the corn fields adjacent to the pheromone traps. Pheromone trapping, black light trapping and egg mass counts will be correlated and compared with degree-day accumulations based on nearby automated weather stations.

2d. Sampling plans will be developed for WBC egg masses in field corn. Data on incidence of egg masses will be collected in commercial cornfields and experiment station fields across the WBC cutworms range. In general, fields will be monitored each year and starting with the first catch of WBC moths, egg mass sampling will be conducted every 5 days during the moth oviposition period. The egg mass distribution(s) will be described and a sequential sampling plan developed for WBC egg masses. Sequential sampling plans have the potential to decrease sampling time to reach a decision, particularly when the populations are low or high, and allow sampling effort to be directed to situations which are approaching threshold levels.

2e. The dispersal, survival and distribution of WBC larvae on and between corn plants will be characterized across the WBC current range. In general, different stages of corn will be infested with 1 or more egg masses as described in 3a. The distribution of the larvae on the plant will be evaluated through time by plant dissection and Berlese funnel larval extraction. The effect of plant stage and density of infestation on distribution of the larvae will be characterized. The dispersal behavior of the larvae between corn plants also will be characterized. Single plants will be infested with egg masses and plots monitored for the presence of natural infestations. Larval presence, plant injury, and the number of the larvae will be recorded on all corn ears in all plants within a 20 feet diameter from the release point of the eggs. If larvae are detected10 feet from the release point, the evaluation will continue for 10 more feet in each direction. Linear regression analysis will be conducted on the dispersal of the larvae from the release point in and across rows.

2f. OH will lead an effort mapping the distribution of overwintering WBC. High infestations will be overlaid on soil type distribution maps to determine if sandier soils are more likely to support overwintering. Life history characteristics will be determined and compared to characteristics in western states. MI and ONT will cooperate to characterize WBC in the Great Lakes region. The influence of growing degree days on WBC life stage development will be evaluated to improve management strategies and timings. Preliminary work in MI suggests WBC survives better shortly after egg hatch than in its original range in the Great Plains. The impacts of environmental conditions on egg and larval survival in the Great Lakes Region will be examined.

2g. The range expansion of the WBC will continue to be monitored and overwintering success will be examined. Host range tests will be conducted to determine if WBC has the potential to feed and survive on other host plants found in MI, PA and ONT, and experiments will determine if a "biotype" exists that prefers dry beans over corn. PA will run trapping networks for both WBC and black cutworm. Time of arrival of black cutworm in spring in combination with degree-day accumulations will allow prediction of cutting behavior. WBC arrived in PA in 2009 and trapping efforts will be used to track their spread and the incidence of larval damage. PA also will reexamine the WBC sex pheromone, which seems to attract many non-target moths. The current pheromone blend is based on limited information, so there is good potential for improvement, making trapping easier and potentially more efficient.

Objective 3. Investigate ecology, evolution, genetics, and behavior of pest Lepidoptera. NE, ONT, QUE, MI, IA, MN, OH, KS, PA, NY, TX, LA, DE.

3a. ECB populations are lower than historical averages in some regions, thanks to high adoption rates of Bt-corn technology. The ECB will not disappear, but it is unclear whether subpopulations that attack vegetables and sweet corn will be differentially affected by widespread Bt corn adoption, and studies in Quebec, IA, and PA will address alternative host use by ECB. This trend provides a unique opportunity to investigate ECB population dynamics and resistance management assumptions at low pest densities. If current selection pressure by Bt corn is directly or indirectly affecting sex ratios, these impacts may influence mating success, and ECB could experience additional population suppression not currently accounted for in IRM models. These issues will be addressed in a project led by MN that involves annual collection of ECB adults across its range for first, second and univoltine generations to measure sex ratios, the percentage of mated females, mating frequency, and the percentage of male and female moths infected with the microsporidian Nosema pyrausta, a widespread obligate parasite of ECB.

3b. DE will lead a geographic survey of ECB pheromone races, including frequency 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 host plant use and movement. DE will continue to provide pheromone analyses for cooperators, the most accurate way to differentiate races, and will help transfer this technology to IA to share the load. IA will seek a molecular marker for diagnosing pheromone race. IA will investigate population genetic differentiation and gene flow within the E pheromone race and its association with possible ECB host races.

3c. NY will continue to assess conventional synthetic insecticides, biologicals and genetically engineered insect-resistant plants for their effects on predators and parasitoids of insects such as ECB, corn earworm, and fall armyworm. The effects of management strategies on these natural enemies should be considered for sustainable production of sweet and field corn. Interstate cooperators will include companies that produce transgenic insect-resistant plants and companies that manufacture conventional and biological insecticides. NY will work with colleagues in IA who are involved with testing products on non-target organisms. IA will determine the nature and degree of potential impacts of transgenic corn on non-target organisms and determine harmonized methods for insecticidal proteins. The harmonization process will involve parallel testing of protocols at three or more laboratories. The tested insects will be selected from a list of surrogate species provided by the EPA or from newly identified surrogate species. The same well-established source colonies of insects will be used to minimize experimental variability.

3d. LA will lead investigations on occurrence/abundance of stalk boring pests on corn to determine species, distribution, overwintering, and damage caused in the mid-south region of the U.S. Occurrence and overwintering of corn borers and plant damage at different plant stages will be investigated by sampling corn stalks and other hosts across the major corn areas in the mid-South. In each state, 4 to 10 locations will be selected for field surveys. In each location, at least 100 plants of each non-Bt corn (and other host plants) and Bt-corn hybrids will be randomly sampled to record the number of insects and bored stalks. WI will continue to examine organic soil and crop fertility effects on corn nutrition and lepidopteran pest response.

3e. LA will a study investigating larval movement and distribution of sugarcane borer and corn ear worm in different patterns of mixed planting of non-Bt corn and Bt corn with pyramided genes. Larval movement and distribution of sugarcane borer and corn ear worm will be evaluated in four different patterns of seed mixtures in open field and greenhouse conditions with natural and artificial infestations. These four different treatments will be 1) all non-Bt plants with one Bt plant in the centre, 2) all Bt plants, 3) all non-Bt plants, and 4) all Bt plants with one non-Bt in the center.

3f. IA will lead a collaborative effort to develop genetic markers and other genomics tools for lepidopteran pests of corn. Resources will be developed for research community-oriented data interaction along with tools for data analyses, which will facilitate annotation of function and pathway interactions of gene sequences within Lepidoptera. This will be accomplished though the annotation of available DNA and translated DNA sequence data searches of available databases. The database structure will allow interaction with inclusive information, determination of hierarchical position and functional relevance of experimental data, as well as creation of an environment for interpretation of results and genetic/genomic assay development. Information within the database will be applied for the development of additional SNP markers for ECB, and de novo development of SNP markers for corn earworm and WBC.

3g. IA will lead an effort to survey for and take advantage of transient genetic structuring in WBC populations that is likely being generated by founder effects along the invasion front to estimate gene flow. Samples from the home range and along the front have been collected and stored by cooperators over the last two years, and new samples are anticipated from other eastern states as they are invaded. Standard population genetics analyses, including FST estimates, Nm estimates, and population assignment techniques will be conducted using a panel of single nucleotide polymorphism (SNP) markers currently under development.

Objective 4. Employ electronic delivery methods to disseminate information related to sustainable management of Lepidopteran pests. MI, ND, NE, OH, ONT, TX, WI, MN.

4a. An NC-205 video library website with permanent high quality versions of IPM videos will be established for clientele access online and download to computer and portable electronic devices. A YouTube channel will be established that will facilitate video contributions and clientele access to smaller file size videos. The goal is to develop a comprehensive series on Lepidoptera corn pests with regional and national/international IPM emphasis. This multiple delivery approach will allow clientele to access and download digital video products in high quality, as well as quick access to smaller, shorter videos on YouTube. 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. An online version of NCR-327 European Corn Borer Ecology and Management will be created. The electronic version will be available free of charge on a more dynamic platform than the print version and allow for continuous updating. The online publication will provide an expanded, interactive format with economic threshold calculators, corn insect IPM videos, pest trapping reports, and pertinent links. Print and CD/DVD educational materials and IPM training videos will be available for purchase through the online site. Each page of the online NCR-327 publication will function as a stand-alone resource for clientele who may not otherwise purchase the print edition. The NCR-327 electronic version can also be used to obtain important feedback from stakeholders. Online surveys will assess grower needs and opinions concerning corn IPM and adoption of IRM practices. These data could then be used to balance logistical and economic expectations for effective corn pest management with the desire to maintain long-term durability of new technologies. Outputs from NC-205 activities will be featured on the NCR-327 online publication.

4c. Individual state and province field crop extension entomology programs are increasingly offering distance education workshops to clientele. The National Corn Growers Assn. has collaborated with NC-205 extension entomologists to deliver Bt corn IRM distance education workshops to growers and consultants. NC-205 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 on-demand online access. States and provinces may allow us to bundle videos and the distance education workshops mentioned above for CEU credit. This would enable NC-205 to offer high quality versions on DVD and send them to county agents or other instructors and IPM field scout training programs nationally and internationally. This digital media could be played at extension meetings and agronomist, 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.

Measurement of Progress and Results

Outputs

• A publication documenting the benefits of Bt corn from the areawide suppression of European corn borer populations
• A comprehensive western bean cutworm IPM management publication
• Western bean cutworm monitoring methodology and tools (e.g. improved pheromone traps) that will trigger field scouting
• Online IPM training modules and decision support tools for corn Lepidoptera
• A rapid translation of research results into technology transfer tools
• Output 6 Website use reports as measures of program delivery; Output 7 Online user survey (pre- and post program) reports of knowledge gain; Output 8 Recommendations to growers related to the use and implementation of refuge seed blends; Output 9 Publications that evaluate movement of various lepidopteran larvae in blended seed (Bt and non-Bt) fields; Output 10 Insect resistance management models that evaluate new technologies and evolving IRM practices; Output 11 Guidelines for monitoring for Lepidopteran resistance to Bt corn; Output 12 A rapid method to screen for resistance alleles in the field; Output 13 Identification of pest management tools that are less harmful to natural enemies and fit the goals of IPM programs for stalk boring insects; Output 14 A core group of harmonized methods, especially for Tier 1 tests, to assess non-target effects of genetically engineered plants; Output 15 Sensitive tools for estimating resistance allele frequencies among field populations using expressed resistance genes linked to a set of molecular markers; Output 16 Genetic markers for several species of lepidopteran corn pests; Output 17 Regulators, companies and farmers will be able to promote products that fit the goals of sustainable production of sweet and field corn in the US.

Outcomes or Projected Impacts

• Cumulative benefits to Bt and non-Bt maize due to a suppressed European corn borer population during 13 growing seasons are conservatively estimated at more than $6.1 billion for a 5-state region, with cumulative benefits to non-Bt maize accounting for almost $3.9 billion of this total.
• An improved program for monitoring for European corn borer resistance to Bt corn would help safeguard Bt technology for growers.
• Blended seed refuge would increase grower productivity across the Corn Belt and reduce the likelihood that European corn borer would develop resistance to Bt corn.
• Growers and consultants will have practical methods to monitor for western bean cutworm adults so they can initiate field scouting and avoid undue economic loss to either the pest itself or the increased mycotoxin contamination it might cause.
• Online publication of outputs will expand clientele access to corn insect IPM decision support tools and increase implementation of IPM for corn lepidopteran pests.
• Outcome/Impact 6 A new extension audience will be reached through expanded access; Outcome/Impact 7 Input efficiencies through IPM decision support tools will reduce corn lepidopteran pest management costs to growers; Outcome/Impact 8 Extension specialists and extension agent links to NC-205 digital media in local newsletters will provide multiplier effect in provision of authoritative, supplemental IPM information at the local level; Outcome/Impact 9 A rapid method to screen for resistance alleles in the field will allow low cost screening over large geographic areas and provide a dependable method to quickly assess whether resistance has developed; Outcome/Impact 10 Documentation of off-site suppression of ECB populations and the associated benefits will provide the validation and impetus for extension activities to train farmers and processors to judiciously apply insecticides according to treatment thresholds based in field scouting and insect trap monitoring; Outcome/Impact 11 Results from this project will have a major influence on regulators in their efforts to assess comparative environmental costs and benefits of IPM systems involving Bt or other transgene technology; Outcome/Impact 12 Data collected from this project over the next five years will be used to modify existing models to assess the impact of changing ECB dynamics on IRM for a range of Bt corn refuge scenarios, which will directly influence refuge requirements imposed on growers using Bt corn; Outcome/Impact 13 Harmonized protocols for testing impacts of transgenic crops will foster communication among scientists and regulators and ultimately will contribute to science-based decisions related to the regulation of genetically engineered plants; Outcome/Impact 14 The long-term sustainability of transgenic plants for insect control will provide significant economic benefit to U.S. agriculture; Outcome/Impact 15 A viable insect resistance management (IRM) strategy that incorporates seed mixtures for the refuge component will directly benefit growers because refuge will be easier to deploy, not only ensuring compliance, but saving growers money; Outcome/Impact 16 The resulting genetic markers will be available for application in population genetics and linkage mapping. Furthermore, functional gene annotations within the database will serve as a cornerstone for biological interpretation of genes that are differentially-expressed among Bt resistance phenotypes; Outcome/Impact 17 Increased adoption of sustainable corn pest production and a reduction of negative impacts to the environment and human health.

Milestones

(2010): Publish updated edition of the NCR-327 publication <i>European Corn Borer Ecology and Management</i>; Submit manuscript on European corn borer areawide suppression and its economic consequences; Submit manuscript on European corn borer male age, mate choice and movement behavior.

(2011): An enhanced online version of NCR-327 publication is established; Submit review on short-range mating behavior in Lepidoptera; Submit manuscript on western bean cutworm population genetics; Launch NC-205 Corn IPM You Tube channel.

(2012): Submit manuscript on select western bean cutworm biological parameters; Submit manuscript on western bean cutworm economic injury levels and thresholds; Development of comprehensive IPM management recommendations for western bean cutworm in its western range; Publish manuscript that evaluates the movement of European corn borer larvae and its impact on blending Bt and non-Bt seed for refuge.

(2013): Submit manuscript on western bean cutworm sampling; Comprehensive IPM management tools are put on the NCR-327 webpage and/or participating NC-205 faculty web pages; Development of recommendations for growers considering refuge seed blends; Genetic analysis to assess host races within E race completed.

(2014): Development of guidelines for monitoring for Lepidopteran resistance to Bt corn; Publish manuscript that evaluates the movement of corn earworm larvae and its impact on blending Bt and non-Bt seed for refuge; Electronic media use surveys are completed and results are published.

Projected Participation

View Appendix E: Participation

Outreach Plan

Members of the NC-205 are involved in field demonstrations and outreach efforts related to the sustainable management of lepidopteran pests of corn. 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 IRM requirements associated with Bt-corn. 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 extension meetings and educational programs conducted by Extension entomologists will be held with producers, industry, consultants, and regulators to discuss findings, and share information, questions 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, 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 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 decision support to clientele.

Organization/Governance

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 the chairperson, secretary, and the administrative advisor. The executive committee will conduct business between meetings. Subcommittees may be named by the chair as needed for specific assignments such as developing new project outlines for continuing the project, to prepare publications, or other assignments. 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 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 technical committee and executive committee. The administrative advisor authorizes the meeting 90-120 days in advance. The chair prepares or supervises preparation of the annual report of the project. The secretary prepares minutes of the annual meeting and forwards them to the administrative advisory who distributes them to the regional research office, the CSREES liaison person, technical committee members, all North Central AES directors, and directors of other participating states. Procedures outlined in the manual for Cooperative Regional Research will be followed.

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