Research

Research Projects

• Arboviral Suppressors of RNA Interference
  The yellow fever mosquito, Aedes aegypti, is a prolific vector of human disease. Our long-term goal is to develop new methods for controlling arthropod-borne viruses based on understanding at the molecular level the virus-vector interactions occurring in the mosquito. It has been well demonstrated that arthropod-borne viruses are susceptible to the RNAi responses found in mosquitoes. Thus, RNA interference (RNAi) may play a role in several potential barriers to pathogen transmission present within the vector mosquito. The HYPOTHESIS to be evaluated is that arthropod-borne viruses have evolved to encode suppressors of the RNAi response within their genomes. The specific aims of this proposal are to: (1) Use stable germline transformation to establish and validate an Ae. aegypti “RNAi sensor” strain. (2) Use the sensor strain generated to assay candidate arthropod-borne viruses for the presence of silencing suppressors. Completion of these aims will also generate a novel assay system for the study virus-vector interactions, mosquito genetics, and virus genetics.
  
  
• Granulated ambrosia beetle
  Granulate ambrosia beetle management is of great concern to the wholesale nursery industry. Tree losses can be severe. Seasonal trapping for this insect has led to management strategies that reduce risk of crop losses.
  
  
• Improvements in Baiting Technology for Household Pest Management
  Over the last decade gel bait bait formulations have become the preferred method of German cockroach control. The single greatest advantage of using gel baits is that they have been highly attractive to German cockroaches so that bait consumption and subsequent mortality result in superior control. However, within the last decade there have been documented cases of "bait aversion" among field populations of German cockroaches. Bait aversion is manifested by cockroaches avoiding a bait formulation that they would previously consume. This avoidance develops as the result of selection for aversion to the food ingredients within the bait matrix rather than to the active ingredients. Most of these populations were from locations where poor sanitation was a problem and baits had been used for extended periods to keep chronic cockroach infestations to a minimum. As the bait aversion behavior becomes more widespread there is an urgent need for new baits to be formulated that provide all of the advantages of the older formulations, but do not elicit aversion response. Bait manufacturers have been re-formulating their bait matrices to replace ingredients that cause the averse behavior. Our laboratory has been evaluating these new formulations and their sugar attractants to determine how "bait averse cockroaches" respond to them.
  
  
• The Efficacy of Bed Bug Management Products and Strategies
  Virginia Tech is currently one of two universities in the nation that is rearing bed bugs for research. Bed bugs promise to be a very important area of research because they are blood feeders, prolific, and difficult to control. The liability issues associated with bed bug presence have already resulted in hundreds of thousands of dollars being awarded to people who have been bitten by bed bugs. My research has focused on evaluating the efficacy products labeled for bed bug control and those that have potential as a bed bug management tools.
  
  
• Beneficial insectary plants to enhance arthropod natural enemies in vineyards
  In spring 2007, we will establish plantings (~0.1 acre) of each of three commercial insectary plant mixes in randomized complete blocks with 4 replications in vineyards in Virginia (The Vineyard at Point Breeze, Belle Haven, VA) tfoster populations of natural enemies.
  
  
• Bioassays of acaricides with twospotted spider mite
  Management for twospotted spider mite, Tetranychus urticae Koch, populations in peanut, Arachis hypogaea L., relies on acaricides. The outcomes of acaricide applications are most predictable when complete information on their toxicity and specificity is available. Specifically, the degrees to which acaricides impact different stages of T. urticae and natural enemies combined determine the overall efficacy of an acaricide application. The objectives of this study were to determine stage-specific direct and residual efficacies of three acaricides (fenpropathrin, etoxazole, and propargite) against T. urticae, and the direct and residual toxicity of the acaricides to Orius insidiosus (Say) adults. Direct toxicity of acaricides to T. urticae was measured on peanut cuttings. All acaricide treatments caused significant mortality to a mixed stage population of T. urticae, and mortality did not differ among the acaricides 7d after treatment. When toxicity to eggs was tested, the proportion of eggs that hatched for all acaricide treatments was significantly lower than the control, with etoxazole and propargite causing 100% mortality. Exposure to acaricide residues caused 30% mortality of T. urticae adults 1 and 2 d after treatment and was not significantly different from the control. Fenpropathrin and propargite caused 100% mortality and etoxazole caused 50% mortality of O. insidious adults after direct exposure to the acaricides. Residual toxicity of acaricides to O. insidiosus adults varied but remained toxic to O. insidiosus longer than to T. urticae. Fenpropathrin had the longest residual effect on O. insidiosus adults, causing 95% mortality after 14 d; etoxazole and propargite caused 30% mortality after 14 d.
  
  
• Evaluation of Biological Control Agents on Target and Nontarget Weeds, and Associated Insects → website
  Impact of biological control agents on nontarget plant species and their associated insects will be studied at selected field sites. Counts of biological control agents will be recorded on nontarget plants. Impact on target and nontarget plant diversity and density will be determined by measuring changes in plant diversity at the selected sites. Statewide surveys will be conducted on the distribution of the established biological control agents.
  
  
• Biological Control of the Mahogany Shoot Borer
  Presence of weaver ants in mahogany plantations in Malaysia is correlated with reduced attack by the mahogany shoot borer. Studies are being conducted to improve our understanding of the system and help us develop augmentative approaches toward using the ants as biological control agents.
  
  
• Biological Control of the Tree of Heaven
  Tree of heaven is an established weed tree from Asia that is invading disturbed habitats throughout much of the U.S. Two weevil pests of the tree in China are being imported and studied in quarantine. They are considered potential biological control agents for this weed pest.
  
  
• Biological Control of the Hemlock Woolly Adelgid
  We are part of a large scale effort to manage the hemlock woolly adelgid in the eastern U.S. Our work encompasses the complete spectrum of biological control activities including foreign exploration, quarantine evaluation, mass production, release, and evaluation of approved insect natural enemies. You can read more about our work at http://www.research.vt.edu/resmag/2007summer/bugs.html
  
  
• Biological control of European corn borer with Trichogramma ostriniae
  Trichogramma ostriniae is a tiny parasitic wasp that was brought to the U.S. from China in the mid-1990s. Research in New York and other northeastern states has demonstrated strong potential for biological control of European corn borer in sweet corn. Current research projects by Tom Kuhar in Virginia include: 1) evaluations and optimization of the parasitoid for ECB control in peppers and potatoes, 2) dispersal of the parasitoid after augmentative releases, 3) effect of crop architecture on parasitoid behavior, and 4)integration of pesticides with T. ostriniae.
  
  
• Biological control of woolly apple aphid
  The woolly apple aphid (WAA), Eriosoma lanigerum, is a cosmopolitan pest of apple. In the mid-Atlantic region, WAA can simultaneously infest the roots and aerial portions of apple trees and can have significant adverse effects on the establishment of young trees. The loss of certain broad-spectrum pesticides under the 1996 Food Quality Protection Act has created the potential for the resurgence of some secondary apple pests, including WAA. A specialist parasitic wasp, Aphelinus mali, has been considered the main biocontrol agent of WAA in the US and abroad. We have discovered that two generalist and one specialist species of hover fly are abundant and important predators of woolly apple aphid early in the growing season, before A. mali becomes abundant. Furthermore, larvae of the specialist hover fly, Heringia calcarata, are purported to prey on both root and shoot colonies of WAA. The objectives of this project are to understand the roles of these hover fly species in the suppression of WAA and the influence of biotic and abiotic factors on populations of WAA and its natural enemy guild. Documenting and quantifying the life history and predator/prey association between H. calcarata and WAA are key goals, as well as understanding the intraguild interactions among predators and the parasitoid.
  
  
• Virginia Apiculture Program: IPM of Honey Bee Colonies, Queen Breeding and Pollination
  Virginia beekeepers have suffered serious colony losses due to the introduction of parasitic mites. The Apiculture Program is designed to improve the pest management practices utilized by beekeepers through the development of research and extension programs. The program will also involve the development of queen breeding programs within the state, and the initiation of programs to improve and promote the use of honey bees for pollination. In addition the program will involve the development of an Africanized Honey Bee Response Plan in collaboration with VDACS.
  
  
• Effectiveness of techniques for freshwater biomonitoring using benthic macroinvertebrates
  We have a longstanding interest in improving benthic macroinvertebrate-based biomonitoring methods and data analyses to draw valid conclusions about the environmental health of streams and rivers.
  
  
• Development of Insect Neuronal Cultures
  Relatively little work has been done on the development of monolayer neuronal cell cultures of invertebrates. This project aims to develop a simple technique for producing large amounts of insect neuronal tissue from an immortal cell line.
  
  
• Boll removal studies in cotton
  In developing management strategies for hemipteran pests in cotton (Gossypium hirsutum L.), it is important to understand the potential of plants to compensate for loss of the fruiting structures. Because of its northern latitude, Virginia has fewer available heat units relative to other cotton-producing states. Therefore, there may be limited opportunity for compensation relative to more southerly production areas. Previous work in Virginia demonstrated that cotton can sustain relatively high levels of first position square loss with no yield loss. This study evaluated the impact of a single event loss of 10 to 14-d-old bolls via mechanical removal on cotton lint yields with the premise that boll loss would have greater impact than square loss as less time and fewer heat units are available for compensation. Field experiments examining four levels of boll removal (0, 5, 15, and 20%) were conducted in 2001, 2002 and 2003. Each boll removal level was imposed at three different dates, beginning 2 wks after first flower and at 3- to 5-day intervals thereafter. Yields ranged from 1103 to 1422 in 2001, 909 to 1124 in 2002, and 843 to 1015 kg lint per ha in 2003. There were no significant differences in lint yields among the boll removal dates or removal levels. The results of our study showed that cotton in Virginia, which approaches the northernmost latitude for cotton production, is capable of sustaining losses as high as 20% of 10 to 14-d-old bolls at a single removal event without affecting lint yield. Results were consistent despite the wide variation in rainfall and temperatures during the three study years.
  
  
• Antifeedants, Repellants, and Organic Controls for Tarnished Plant Bug and Japanese Beetle on Caneberries → website
  This project deals with efficacy of pesticides that are appropriate given the restrictions imposed by preharvest intervals for pests that attack ripening berries. A related resources is a web page (linked below) that was supported by the North American Bramble Growers Association.
  
  
• Cataloguing specimens of aquatic insects in the Department of Entomology Collection
  We have begun to catalogue all of the specimens of aquatic insects housed in the Department of Entomology Collection that have been identified to species. The data are being stored with software designed specifically for museum collections.
  
  
• Cockroach Reproductive Physiology
  Traditionally, cockroaches have been considered pests on the basis of their presence in human dwellings, odors, their ability to acquire, harbor and transmit human pathogenic organisms. More recently, it has been shown that the presence of cockroaches in urban habitations can promote serious asthma reactions in humans, particularly in children. A variety of methods have been developed for cockroach control, but many have become less effective due to the development of pesticide resistance. As a result, there is a need for continued basic studies on cockroach biology to develop new pest control strategies for controlling these insects. Research in our laboratory is focused on cockroach reproduction physiology designed to examine the relationship of developing German cockroach embryos enclosed in an egg case that remains attached to the female until hatch.
  
  
• Commercial Turfgrass IPM: Novel Insecticides for Managing White Grubs and Cutworms
  The annual white grub complex and black cutworm are two of the most important pest groups affecting turf in Virginia. Insecticide management costs for these pests alone are estimated at hundreds of thousands of dollars annually. Recent industry research has produced two new insecticides, chloroantraniliprole for white grubs, and indoxacarb for cutworms. My current research on Virginia sod farms and golf courses is evaluating timing and rate options for these materials. It is expected that our findings will improve resistant management options for white grubs and cutworms as well as other important pests of commercial turfgrass in the near future.
  
  
• Concept Mapping on the Web
  Evidence suggests that students of agriculture generally do not possess a strong disposition for critical thinking. In addition, instructional goals and assessment in agricultural education are often not aligned. With pressure on educators to integrate science into agricultural education, instructors are being asked to find innovative ways to use computers for the delivery and assessment of instruction, encourage student learning beyond the classroom, and promote cooperative learning and collaboration in the delivery of instructional material between science- and agricultural-based disciplines. An efficient, cost effective, and discipline-independent method to improve students' disposition toward critical thinking is with concept maps. A concept map is a graphical tool that uses concepts and the relationships between and among them to represent an individual's cognitive structure (the way the individual thinks). The primary goal of this project is to develop a web-based concept mapping tool (CMT) that can be used to facilitate instruction, student learning, and collaboration in agricultural science education. The CMT would help to build student competencies for cognitive thinking by allowing them to integrate and synthesize old and new knowledge across science-related disciplines.
  
  
• The Cost of IPM for German Cockroach Control in Public Housing
  The long-term costs and efficacy of two treatment methods (traditional pesticide spray applications and IPM) for German cockroach control were compared in a Virginia Public Housing facility. The results idicated that the cost of IPM was significantly greater than that of the spray applications with the majority of the cost being attributed to technician time. However, the efficacy of IPM was als signficantly greater. Cockroach trap catch in the IPM treatment was signficantly reduced by month 4 and the populations remained supressed for thrououth the year. Trap catch in the apartments that received monthly spray applications tripled during the sumer months and were not reduced at any time during the study.
  
  
• Decision-support system for slowing gypsy moth spread → website
  The goal of the USDA Forest Service Slow-the-Spread (STS) project initiated in 1993 is to slow the expansion of gypsy moth (Lymantria dispar L.) populations in the U.S. by early detection and suppression of isolated colonies beyond the population front. The decision-support system is needed to determine the location of potential colonies from data on moth counts in pheromone traps, and to suggest what actions to perform in these areas. Results of analysis are available on the web and can be downloaded by all agencies involved in the STS project in 8 states. Recently the STS project has expanded to Minnesota, Wisconsin, Illinois, Indiana, and Ohio, where gypsy moth populations have a different pattern of spread. Now we work on the revision of the decision algorithm to improve its effectiveness in these new areas.
  
  
• Determining the Impact of northern and southern strains of plum curculio on Interstate Shipment of Virginia Apples → website
  This project attempts to differentiate univoltine and bivoltine southern strains of plum curculio based on biochemical methods, and determination of the within-state distrbution of the two strains. The presence of second-brood larvae in the fruit at harvest will complicate shipment of fruit to certain states and countries.
  
  
• Development of Biopesticides for Grasshopper and Locust Control in Sub-Saharan Africa
  A major problem encountered in development of biopesticides is protection of the agents from desiccation and ultraviolet light. Collaborative work among several VA Tech faculty has focused on development of efficient production and formulation of microbial biopesticides for use in locust control in Africa. We have been successful in coating spores of an entomopathogenic fungi which improves their viability during exposure to UV-B radiation and dry heat conditions characteristic of the African climate. This technology may be developed for protection of a variety of entomopathogenic organisms which might be utilized in insect pest control.
  
  
• Embedded Systems Mobile Computing Data Collection in the National STS Program
  The "Trapper Gadget" is an integrated Pocket PC-based device coupled with a GPS receiver. We have written custom software in Visual Basic in the pocket PC operating system environment that incorporates the trapping protocols of the STS program. The unit is designed as a tool carried by the gypsy moth trapper that facilitates rapid, accurate, and error-free data collection. The Gadget references its internal STS trapping database and thus has complete access to all activities associated with a gypsy moth trap site. Through the GPS receiver, the Gadget associates the trapper's location with its database of sites and allows the trapper to perform legitimate trapping operations.
  
  
• Pheromone based monitoring and management of dogwood borer in southern apple orchards
  The dogwood borer, Synanthedon scitula, is becoming an increasingly important pest of apple grown on size-controlling rootstocks in eastern North America. Monitoring the dogwood borer using commercially available sex pheromone lures has produced discrepant results among published studies, due mainly to the fact that its sex pheromone had not been specifically identified. A collaborative project with USDA and NCSU scientists has led to identification of the dogwood borer sex pheromone, resulting in a tremendous increase in the number of moths captured and a significant improvement in the species specificity of the new lure. Our current efforts seek to determine whether dogwood borer populations in commercial apple orchards can be suppressed through mass trapping of males. As well, cooperators from TN, NC, VA, WV and NY are deploying the new lures in managed urban landscapes, apple orchards and woodlands in each state, to compare the seasonal flight activity and relative abundance of dogwood borer among these habitats.
  
  
• Integrated Pest Management of Specialty Crops in Eastern Europe → website
  
  
  
• Ecology and IPM of Diamondback moth on collards
  Dr. Kuhar is currently researching the ecological aspects and insecticide control of diamondback moth, Plutella xylostella (L.), on collards in two regions of Virginia. Research Objectives: 1.To compare fecundity, mortality, and survivorship curves of P. xylostella between the southwestern and eastern shore regions of Virginia using ecological life table analysis. 2.To assess the species complex and relative impact of parasitoids of P. xylostella, 3.To compare insecticide efficacy, relative toxicity to natural enemies, and resistance levels in P. xylostella between the SW and ES regions. Publication: Cordero, R. J.*, T. P. Kuhar, J. Speese, III, R. R. Youngman, E. E. Lewis, J. R. Bloomquist, A. D. Bratsch, and L. T. Kok. 2006. Field efficacy of insecticides for control of lepidopteran pests on collards in Virginia. Online. Plant Health Progress. doi:10.1094/PHP-2006-0105-01-RS. http://www.plantmanagementnetwork.org/php
  
  
• Ecology and management of wireworms
  Wireworms are the larval stage of click beetles and can be serious underground pests of many crops particularly potatoes. A number of research grants have been obtained by Dr. Kuhar to study the management of this important pest group. Projects include the following: 1) Monitoring species complex, 2)Evaluating sampling methods, 3) Investigating habitat preferences, 4)studying the phenology of wireworms with potato crop development, and 5)Evaluating novel insecticide chemistries and timings for control.
  
  
• Relationship of European corn borer on whole-plant corn yield
  Previous research has focused almost exclusively on the impact of European corn borer on corn grown for grain. Findings from our two-year field study have indicated that 3-4 tunnels per stalk are necessary before economic loss occurs in whole-plant yield. The significance of this is that our field surveys have shown that this level of tunneling pressure rarely occurs in field corn in Virginia. These findings promise to offer growers in Virginia as well as in other Mid-Atlantic states much needed information on the impact of European corn borer on corn grown for silage.
  
  
• Evaluating novel insecticides on vegetable crops
  Novel pesticides, including many biological compounds and biorational chemistries are evaluated annually for control of the major arthropod pests of potato, sweet potato, cucurbit vegetables, cole crops, sweet corn, tomatoes, snap beans, peppers, asparagus, and spinach. Research results help the development of new products and label registrations for the vegetable grower.
  
  
• Evaluation of organic or environmentally selective methods to control Japanese beetle on fruit crops
  The objective is to determine insecticides that will control Japanese beetles on several fruit crops grown in Virginia. Materials will be determined that control Japanese beetles either by killing adult beetles or by preventing their feeding, that meet current days-to-harvest restrictions on commodities where the beetles commonly feed on fruit just before harvest.
  
  
• Fructans: inclusive of inulins, levans, and related fructofuranosides as subterranean termite feeding attractants in termite baiting systems.
  Currently, there are no attractants or consumption enhancement compounds available for use in subterranean termite baiting systems. Therefore, it takes weeks and often months for termites to begin feeding at the bait stations in significant numbers. The addition of these fructofuranoside polymers to the termites bait matrix would be a significant enhancement to these termite bait systems. The addition of compounds like inulin would cause termites to feed preferentially on the bait matrix rather than other local food resources, and influence those termite workers to recruit additional termites to the bait stations.
  
  
• GIS for IPM in Developing Countries → website
  Previous work, funded through the USAID IPM-CRSP, involved developing and conducting workshops in the use of GIS and GPS in IPM programs in developing countries (Jamaica, Uganda, and Trinidad). Current efforts build on this by incorporating a GIS/GPS component of pest managment programs in tomato and coffee in Uganda..
  
  
• Homing Endonucleases and genetic control
  This project aims to determine the potential for the selfish genes called homing endonucleases to serve as a method of dispersing and fixing genes into natural mosquito populations that reduce the vector competence of mosquitoes to transmit pathogens, such as the causative agents of dengue fever and malaria.
  
  
• Impact of hemlock decline from HWA on aquatic insects in freshwater streams
  The goal of this project is to determine the extent to which the decline of riparian hemlock caused by hemlock woolly adelgid (HWA) affects stream ecosystems in the southern Appalachians.
  
  
• Assessing the Value of IPM in Virginia Public Housing
  The goal of this project is to change pest management practices in Virginia public housing from monthly pesticide applications to IPM. In 2002, I conducted a research project designed to answer the question, "What is the cost of IPM?" Many researchers had speculated that IPM would be initially more expensive than monthly pesticide treatments but that the cost would decline as pest populations decreased. However, no dollar figure was ever put on these costs. A year-long study comparing the costs (and efficacy) of IPM to monthly spray applications was conducted in Portsmouth public housing. We concluded that IPM was far more effective at killing cockroaches, but the cost was significantly higher ($4.06/ per unit per month) than that of spray applications ($1.50 per unit per month). In 2005, we conducted a face-to-face survey of public housing residents to introduce them to the IPM concept and benefits. We then asked how much they would value an IPM program. Of 816 respondents, 462 indicated that they would pay an additional $11.32 (average) per month for IPM. These responses indicated that public housing residents did value a superior, reduced toxicity method of pest control. In fact, most placed more value on IPM than the actual cost of the program ($4.06). In 2006, a cost/benefit analysis will be conducted, which will weigh the IPM cost data, and the resident response data, against a risk assessment. A policy brief will be presented to the Virginia division of Housing and Urban Development and other interested parties, in an attempt to interest those individuals in adopting an IPM policy in place of the standard practice of accepting low-bidder pest control.
  
  
• Project Planning Proposal: West African Regional Consortium of IPM Excellence
  Faculty from Virginia Tech, University of California-Davis, Purdue University and Fort Valley State University developed a proposal designed for collaboration with research and extension units from five West African countries in a project featuring Integrated Pest Management (IPM) research on a variety of commodities.
  
  
• Impact of conservation tillage and other cultural practices on tobacco insect pests.
  Research is underway in cooperation with Dr. David Reed of the Southern Piedmont AREC to investigate insect pests and their management on conservation-tilled tobacco. Results indicate that conservation-tillage reduces the incidence of aphids and flea beetles, but its impact on hornworms has been inconsistent. Findings also indicate that flue-cured tobacco grown in conservation tillage systems can produce yield and quality similar to conventional tobacco. Research is being continued to evaluate various cultivation methods, cover crops, and insecticides for managing insect pests on tobacco. This research has helped increase the use of conservation tillage in flue-cured tobacco production in Virginia.
  
  
• Influence of tobacco flea beetle management on the development of black shank in tobacco
  Black shank is a major soil-borne pathogen of tobacco. The objectives of this research are to determine the influence of early-season control of the tobacco flea beetle, a pest that damages young leaves and roots, on the development of black shank in tobacco. Imidacloprid for flea beetle control and metalaxyl, a fungicide commonly used for black shank management, are being assessed for their impact on the incidence of flea beetles and black shank. In a moderately-resistant cultivar, the use of imidacloprid applied as tray drench treatments provided effective early-season control of flea beetles, reduced flea beetle emergence from tobacco root systems, and reduced the number of plants with black shank symptoms by 40% to 50% compared with the untreated check and an early-season application of metalaxyl. This study may lead to improved insect management practices for reducing the incidence of black shank in problem fields.
  
  
• Insect management on transgenic tobacco produced for high-value protein.
  Genetically modified tobacco for valuable proteins has excellent potential for commercial production in the tobacco growing regions of Virginia. This crop will be produced for maximum yield of specific proteins. The plants will be grown at very high densities and clipped three to five times a year. The objectives of this research are to determine the major insect problems and to develop strategies for managing these pests. Preliminary studies indicate that several insect problems on tobacco grown for protein are different from those on tobacco produced for cured leaf.
  
  
• Insecticides for tobacco
  Several potential new insecticides are evaluated annually for use on tobacco. Neonicotinoids were the most promising insecticides tested in recent years. They were clothianidin applied as a transplant water treatment for aphid and flea beetle control and foliar applications of clothianidin and acetamiprid for control of aphids, flea beetles, hornworms and budworms. Acetamiprid is a reduced risk insecticide that was labeled for aphid control on tobacco in early 2005. Previous research contributed to the registration of thiamethoxam (Actara/Platinum), emamectin benzoate (Denim), and lambda-cyhalothrin (Warrior) on tobacco.
  
  
• Genetic Effects of Inversion Polymorphism in Anopheles gambiae
  Ecological, behavioral, and physiological adaptations related to malaria transmission are often associated with chromosomal inversions (genome rearrangements that result from flipping a chromosomal segment) in the mosquito genome. Our goal is to understand the mechanism of how polymorphic inversions affect the ability of a mosquito to transmit malaria parasites and to adapt to diverse environments. This line of research will ultimately lead to the development of novel strategies for malaria control, such as immune regulators that disrupt parasite development in the mosquito.
  
  
• Emerging Foci of La Crosse Encephalitis Virus Activity
  La Crosse (LAC) virus is the leading cause of pediatric encephalitis in the U.S. Since its discovery approximately 40 years ago, most cases have been reported from the upper Midwestern states. However, in the past decade a southeastern focus of LAC virus has emerged with increasing numbers of cases being reported from West Virginia, Tennessee, North Carolina, and Virginia. Complicating the situation is the possible involvement of two non-native species of mosquitoes that have recently become established in LAC virus endemic areas. Isolation of LAC virus from several pools of mosquitoes collected in the New River Valley of southwest Virginia in 2002, an area from which no human cases have yet been reported, suggests that LAC virus may be continuing to expand its range in Virginia. The purpose of this research is to determine the extent of LAC virus activity in southwest Virginia. Two hypotheses are being tested in three regions in southwest Virginia. The first hypothesis is that accessory vectors, most specifically Ae. albopictus, are contributing to the increased incidence of LAC virus. Second, that canine seroprevalence can be used as a practical indicator of LAC virus transmission rates to vertebrates in an area.
  
  
• Long term effects of vineyard surroundings of three vineyard pests, and short term control → website
  This proposed project addresses management of grape berry moth (GBM), a key pest of grape throughout Virginia, grape root borer (GRB), a pest that has been sporadic in occurrence but locally severe, and Pierce?s disease (PD), a sharpshooter-borne disease that is of critical concern in the southeastern part of the state. The objectives attempt to deal both with short-term control options, as well as ecological factors that can be used to manage these pests more effectively in the long term. 1. Evaluate role of vineyard surroundings and management approach on incidence of GBM, parasitism of GBM, climbing cutworm pest pressure, diversity of arthropod predators, and abundance of sharpshooter vectors of Pierce?s disease, 2. Compare efficacy of low-risk insecticides for grape berry moth, 3. Evaluate mating disruption technologies, as well as three non-organophosphate pesticides: azadirachtin (botanical), methoxyfenozide (insect growth regulator) and paraquat (herbicide) for control of GRB, 4. Evaluate three trap designs leading towards a GRB monitoring program, 5. Evaluate efficacy of two neonicotinoids for prevention of PD infection.
  
  
• Improved management of aphid-vectored barley yellow dwarf virus in small grains.
  Field studies are underway to evaluate grain aphid populations, strain and occurrence of BYDV in the crop and in associated alternate weed hosts, timing and impact of various insecticide treatments, incidence and severity of BYDV and impact on yield. Five grain aphid pest species are being monitored using yellow, plastic pan traps located in and around the test field, above ground inspection of plant leaves, and below ground inspection of plant stems and roots. Virus is being evaluated in the crop and most common potential weed hosts using the ELISA technique on random samples taken each 6-8 weeks throughout the season. Both seed and foliar insecticide applications are being evaluated for impact on aphid populations, incidence of the disease and impact on crop yields. Results have revealed a new aphid pest species, the rice root aphid, as a potential major source of virus. Pan traps appear to provide a better indication of the species present and their relative abundance, compared with plant and soil samples. About 21 alternate virus hosts have been identified and show positive for the strains also found in the crop. Both seed and well-timed foliar insecticide treatments have provided significant reductions in the incidence and severity of the virus, and increased yields.
  
  
• Refining Mating Disruption Techniques in Gypsy Moth IPM
  Gypsy moth insecticides have evolved from broad spectrum, persistent, environmentally hazardous compounds to highly specific and relatively environmentally benign products. Chief among these new tools is the use of Disparlure, the synthetic gypsy moth mating attractant. This compound is applied aerially and serves as a mating disruptant with profound positive effects in halting gypsy moth mating and subsequent population growth. Our work in the STS Project with fine tuning both the concentration and application of Disparlure has led to an overwhelming increase in the use of this product within the STS Project area. Since 1995, when mating disruption was first used in STS, it has grown from 7% of the 35,238 treated acres to 81% of the over 441,000 acres treated in 2007. We are now able to apply rates of 6gm/acre as opposed to earlier concentrations of 32gm/acre. Disparlure now is approximately 1/3 the cost per acre as Btk and has fewer environmental effects. This is especially valuable in areas with threatened and endangered lepidopteran species.
  
  
• Pink hibiscus mealybug monitoring and management
  The pink hibiscus mealybug (PHM) is a serious pest of a broad range of fruit trees, vegetables and ornamentals and has recently spread from the Caribbean islands to south Florida, where is was first detected in June 2002. The insect is currently under quarantine in Florida, where ornamental nurseries can be temporarily closed for business if APHIS inspectors find just a single colony infesting a plant. Several biological control agents attack PHM colonies, and while they can provide high levels of control, they do not eradicate infestations. Recent identification of the PHM sex pheromone by Dr. Aijun Zhang, USDA-ARS, has greatly facilitated the ability to monitor PHM and offers an opportunity to explore the potential for pheromone-based management in concert with other tactics, including biological and chemical control. This project involves use of the PHM sex pheromone for monitoring and management and research on aspects of the ecology and behavior of PHM that relate to its pest status in the United States.
  
  
• Blockers of Voltage-Dependent Chloride Channels as New Nematicides
  The toxic and environmentally unfriendly compound, methyl bromide, is being phased out as a broad specrum nematicide by the EPA. Accordingly, alternatives are urgently needed to protect crops from nematode-induced root damage, and we are addressing this need by evaluating a number of compounds known to block chloride channels.
  
  
• An inhibitor-based suppression tactic for southern pine beetle → website
  During the 1980's and 1990's we were part of a team responsible for developing a suppression tactic based on the southern pine beetle produced inhibitor-pheromone, verbenone. The tactic was approved by EPA in 1999, but is still not operational or commercially available.
  
  
• Orange striped oakworm
  Implementation of IPM strategies including targeted scouting and use of microbial insecticides led to an 85% reduction in insecticide usage after 2 years and 100% reduction after 12 years.
  
  
• Evaluating the pest management potential of the use of pheromones and plant attactants of Colorado potato beetle
  This research is a special cooperative research agreement between Dr. Kuhar and Dr. Dick Dickens (USDA-BARC-Chemicals Affecting Insect Behavior Lab). The use of attractants and pheromones that draw beetles to a point source may greatly reduce the amount of insecticides necessary for effective control of Colorado potato beetle (CPB) in potatoes and other solanaceous crops. Over the past few years, Dr. Dickens has demonstrated that several synthetic kairomone blends, based on the volatiles produced by potato plants, are attractive to CPB. More recently, he and his colleagues identified a male-produced aggregation pheromone, (S)-CPB I, and discovered that the combination of pheromone and plant attractant is more attractive than the plant attractant alone. Field studies in Virginia have demonstrated the attractiveness of the pheromone under field conditions, the potential for the pheromone in a trap crop IPM strategy for CPB, and the assessment of potential attracticide formulations.
  
  
• Combined effects of alfalfa weevil and potato leafhopper on yield and forage quality of glandular-haired alfalfa → website
  A three-year Virginia field study found that a commercial leafhopper-resistant alfalfa variety did not provide acceptable resistance to potato leafhopper. Our cost-benefit analysis indicated that growers who planted this ineffective variety lost nearly $31 more per acre than growers who planted one of the many standard, non-leafhopper resistant varieties suited to Virginia.
  
  
• Pesticide Waste Disposal
  Pesticide disposal research has focused on development of a biologically-based system for cleanup and detoxification of pesticide wastes. Equipment has been developed and is being used to cleanup pesticide rinsewater wastes. The treatment system consists of batch sorption of pesticides onto an organic sorbent (e.g. peat), followed by separation (filtration) and finally degradation of sorbed pesticide in bioreactors during solid state fermentation (SSF). Field experiments are being conducted at three Virginia Agricultural Research and Extension Centers (AREC's) to evaluate the effectiveness of the process with regard to human effort, safety and economics and environmental safety. A second area which is being addressed is the bioremediation of soils contaminated with pesticides resulting from accidental spills. Investigations deal with the use of organic sorbents and other amendments such as used vegetable oil soil in an effort to first retard pesticide movement and subsequently to facilitate biodegradation.
  
  
• Insecticide Exposure and Parkinsonism
  These studies have analyzed a number of insecticides and their potential to cause behavioral and neurochemical hallmarks of Parkinson's disease. We are also evaluating new therapeutic agents for treating or preventing Parkinson's disease.
  
  
• Pattern of Genome Rearrangements in Malaria Mosquitoes
  Our long-term goal is to elucidate the role of genome rearrangements in mosquito evolution, adaptation, and ability to transmit malaria parasites. Identification of chromosomal determinants of speciation and adaptations will improve our understanding of the origin and evolution of mosquito vectorial capacity.
  
  
• Reduced Pesticide Use in Bee Hives through the Development and Promotion of an IPM Program for Mite Parasites
  The U.S. beekeeping industry has faced serious challenges after the introduction of the parasitic mites, Varroa destructor and Acarapis woodi. The mites have lead to a significant delcine in the number of managed colonies. Effforts to control the mites have lead to an over-reliance on acaracides and chemical fumigants. Our goal, therefore, is to develop and promote an IPM program that not only provides beekeepers with alternative approaches for the management of mite parasites, but reduces pesticide use and the potential for honey and wax contamination. We will also sample hives (honey and wax) for miticide residues to allow us to monitor changes in hive product contamination.
  
  
• Risk Avoidance and Mitigation Program (RAMP)
  The USDA "Risk Avoidance and Mitigation Program" (RAMP) is intended to address and assist growers with the transitions stemming from ongoing pesticide regulatory changes under the Food Quality Protection Act (FQPA). A collaborative effort among tree fruit entomologists from seven eastern states has been supported by two consecutive RAMP grants, designed to develop arthropod pest management programs that rely exclusively on “reduced risk” and “organophosphate-replacement” products and tactics. Our ultimate goal is to develop programs that are effective and affordable to the grower and that conform to the tenets of less risk to the consumer, the agricultural worker and the environment.
  
  
• Role of insecticides in reducing incidence of tomato spotted wilt virus in peanut
  Tomato spotted wilt virus (genus Tospovirus, family Bunyaviridae, TSWV), transmitted by many thrips species, is one of the most devastating pathogens of peanut (Arachis hypogaea L.). Recently, TSWV has become a serious problem in the Virginia/Carolina peanut growing region of the United States. During 2002, TSWV was present in 47% of the North Carolina hectarage and caused a 5% yield reduction in Virginia. Factors that influence levels of TSWV in runner market-type peanut cultivars, which are primarily grown in Alabama, Florida, Georgia and Texas have been integrated into a risk advisory to help those peanut growers reduce losses. However, there are inherent differences between runner and virginia market-type peanut cultivars which are primarily grown in the Virginia/Carolina region. In 2003, a preliminary risk advisory was released for virginia market-type peanut grown in the Virginia/Carolina region. One factor in both advisories is the use of insecticides to reduce the vector populations and disease incidence. This research elucidated the influence of insecticides on thrips populations, thrips plant injury, incidence of TSWV, and pod yield in virginia market-type peanut. Eight field trials from 2003 to 2005 were conducted at two locations. In-furrow application of aldicarb and phorate resulted in significant levels of thrips control, significant reductions in thrips injury to seedlings and incidence of TSWV, and significant increases in pod yield. Foliar application of acephate following aldicarb or phorate applied in the seed furrow further reduced thrips plant injury and incidence of TSWV and also improved yield. These findings will be used to improve the current virginia market-type TSWV index.
  
  
• Southern Pine Beetle Internet Control Center → website
  A web-based clearinghouse for southern pine beetle information, control strategies, and ongoing research and activities.
  
  
• Sampling for the Hemlock Woolly Adelgid
  Ongoing investigations to provide a statistical basis for making population estimates and pest management decisions for HWA
  
  
• Developing a fall sampling method for predicting spring-planted corn fields with economic infestations of secondary insect pests
  Fall sampling for secondary soil insects on corn has become important to corn growers who plan on using seed-applied insecticides for these pests. This relatively new seed-applied insecticide technology requires that growers order this technology at the same time they place their seed orders, which is usually done in late fall or early winter. Consequently, the information gained from standard pre-plant sampling methods typically done two weeks before spring planting is too late to be useful. In fall 2005 and 2006, a standard soil sampling method and a more efficient sampling method we developed for detecting annual white grubs were compared in fifteen fields in eastern Virginia. The results indicated no significant difference in numbers of annual white grubs detected between the two sampling methods.
  
  
• Ecological studies of benthic macroinvertebrates for determining sedimentation impacts in Chattahoochee National Forest streams
  Private organizations have taken legal action against the U. S. Forest Service for not protecting streams in the Chattooga River watershed in accordance with the Clean Water Act. The main problem is sedimentation, but there are questions about the relationships between sediment and benthic macroinvertebrates and the best way to study the problem in this watershed. We have been conducting studies of the smaller streams in the Chattahoochee National Forest for the Forest Service in order to address these questions.
  
  
• Sample analysis and interpretation for the Shenandoah National Park Long-Term Ecological Monitoring System
  After developing the aquatic component of the Long-Term Ecological Monitoring System for Shenandoah National Park in the late 1980's, the Aquatic Entomology Program has continuously performed laboratory analyses of the samples taken by park personnel and assisted with data analysis and interpretation.
  
  
• Using benthic macroinvertebrates to identify causes of fish kills in the Shenandoah River
  Recent massive fish kills in the Shenandoah River have caused a significant loss of recreation and economic benefits in Virginia and have become a high profile issue with the public and state government. There is not a single, readily apparent stressor killing the fish, but intensive agriculture in that part of the state (primarily cattle and poultry) is suspected to be involved. The problem is likely the result of multiple stressors operating interactively for brief, irregular time periods. We will be conducting studies of benthic macroinvertebrates to help identify the cause of the fish kills and to suggest actions to prevent them.
  
  
• Spatial ecology and remote sensing for precision management
  In May 2003, USDA and NASA entered into a collaborative agreement to promote the development of precision agriculture (precision farming), a technology-based and information-intensive area of agriculture. Precision pest management falls within the scope of precision agriculture. However, few attempts have been made to apply precision farming technology to arthropod pest management because of the difficulty creating “bug map” of the spatial variability of pest populations within the field. An attempt was made using twospotted spider mite population infestations in peanut fields in Virginia to assess the feasibility of precision agriculture approaches for the management of arthropod pests in agricultural fields.
  
  
• Investigations on the interaction between spatially separated herbivores on field corn
  Greenhouse studies were conducted in 2004, 2005, and 2006 to examine the reciprocal effects of aboveground herbivory by European corn borer, Ostrinia nubilalis Hübner (Lepidoptera: Crambidae), and belowground herbivory by root knot nematode, Meloidogyne incognita Chitwood (Tylenchida: Heteroderidae), on one another at three growth stages of corn, Zea mays L. Although numerous studies have been published on the interactions between different herbivorous insects on a common host plant, few of this nature have been published on insect-nematode interactions on a common host plant.
  
  
• Using benthic macroinvertebrates to evaluate the effectiveness of stream restoration for improving biological integrity
  Billions of dollars are being spent on stream restoration but the results of these expenditures are unknown, especially in regard to recovery of biological communities, because appropriate post-restoration studies rarely occur. We are addressing this issue by first conducting detailed baseline studies of the benthic macroinvertebrate assemblages in relation to a wide array of environmental variables in an impaired stream where a restoration program has been implemented. Then, the same stream will be studied over a long time frame (at least 5 years) to follow the recovery of biological integrity and explain how these changes are related to stream restoration efforts.
  
  
• Strengthening the Environmental Quality Laboratory of the Central Veterinary Laboratory, Bamako, Mali
  Virginia Tech has committed to an Integrated Pest Management Collaborative Research Support Program (IPM CRSP) 5-year project to provide assistance in developing the capabilities of the Environmental Quality Laboratory (EQL) as a leader in pesticide analytical techniques in Mali and West Africa. Another component of the project is pesticide safety education. Pesticide safety will promote personal and environmental safety. Delivery of pesticide safety lessons will be coordinated with demonstrations of IPM practices developed for horticultural crops in Mali. Proper pesticide use will allow the laboratory to function in a quality assurance role. Several Virginia Tech Personnel are providing technical and educational assistance to this laboratory.
  
  
• Studies in Forensic Entomology
  Insects can be used for the determination of post mortem intervals (PMI) in cases of unknown death. Several approaches may be used for the estimation of PMIs, including the use of maggot developmental times and the use of successional data. Our research has involved the study of insect successional fauna on carcasses, the effects of ante mortem alcohol ingestion on fly development, and the effects of maggot activity on gunpowder residue retention. Current studies involve the dispersal of Oxycontin in the body and its effects on maggot development.
  
  
• Managing Red Imported Fire ants in Virginia
  The first report of red imported fire ants (RIFA), Solenopsis invicta Buren, in Virginia was recorded in 1989. Since that time, several thousand mounds have been identified in the southeastern, coastal regions of the state. The Virginia Department of Agriculture is currently responsible for all RIFA control in Virginia. However, limited resources and the possibility that the RIFA has become established within the coastal regions of the VA has led the Virginia Department of Agriculture (VDACS) to consider placing certain Virginia counties under the Federal RIFA quarantine. One consequence of the quarantine implementation is that FIRA control being transferred to homeowners and pest management professionals within the quarantine areas. Because these individuals have no experience in FIFA control, the Virginia Cooperative Extension services has undertaken a study to evaluate RIFA control products for efficacy.
  
  
• Identification and succession of pest ant species in Puerto Rican housing developments
  The invasive ant species complex was determined within three Puerto Rican housing developments of different ages (one, four, and eight years old). Frequency and relative abundance data were collected and spatiotemporal analysis mapped the location of each species within the sites.
  
  
• Investigation of Novel Approaches for Exploiting and Manipulating the Behavior of Sesiid Pests of Apple and Grape in Virginia
  
  
  
• Bean leaf beetle biology and management in snapbeans
  Snapbeans are a multimillion dollar industry in Virginia. Bean leaf beetle has become one of the most important insect pests of the crop. Adults defoliate young plants and scar pods rendering them unmarketable. The current research of my graduate student, Meredith Cassell, involves assessing the impact of early-season defoliation on pod yield, host preference studies, and novel management strategies.
  
  
• The National Gypsy Moth Slow the Spread IPM Project Information System → website
  The STS Project Information System is the primary information management system for gypsy moth population data from the ten states involved in the National Gypsy Moth Slow the Spread Project. We are responsible for processing, quality control, and distribution of trap catch data in a format usable by project personnel for management decisions. In addition, we are responsible for codifying all aspects of STS Project components into an information systems framework that serves as the structure for seasonal project activities.
  
  
• The development of novel detection and management tactics for grape root borer
  The grape root borer (GRB), Vitacea polistiformis, is a potential threat to wine grape production in the southeastern United States. The long-term availability of the most effective pesticide for managing it and other clearwing borers, chlorpyrifos, remains uncertain due to the review of pesticide tolerances under the Food Quality Protection Act. GRB larvae are subterranean pests, feeding on the roots of vines, making their detection difficult. There are no unequivocal horticultural symptoms that can be used to diagnose GRB infestation of vines. Sex pheromones traps are effective at capturing male GRB, but since the insect also infests native vines that are often in close proximity to commercial plantings, the relationship between trap catch and infestation levels remains unknown. We are currently exploring the potential for using acoustic emissions detection technology to monitor the vibrational signals generated by the feeding activity of larval grape root borer on vine roots. This novel approach may enable more precise estimates of vineyard infestation levels and aid in developing the relationship between pheromone trap captures and larval density.
  
  
• Impact of tobacco splitworm on burley tobacco
  The tobacco splitworm, Phthorimaea operculella, is a leaf-mining caterpillar that is becoming an important pest of tobacco in the southeastern United States. In Virginia, it has been a sporadic problem on flue-cured tobacco, but not on burley tobacco. However, since there is a shortage of burley tobacco, companies are encouraging farmers to grow burley in the flue-cured region where splitworms are common. On burley tobacco, splitworm caterpillars cause moderate damage in the field and continue to feed on the leaves and stalks in the curing barn after harvest. Research will quantify splitworm damage to burley tobacco in the field and in the curing barn. The impact on leaf quality will be compared for various levels of leaf injury for each stalk position. Splitworm development on plants in the curing barn will be investigated. Pheromone traps will be used to monitor adult flight activity in the field and in the curing barn to assess their value for predicting splitworm outbreaks. Several insecticides will also be evaluated for splitworm control.
  
  
• Virginia IR-4 Minor Use Pest Control Clearance Program → website
  The IR-4 Minor Use Pest Control Clearance Program was established in 1963 by the state land-grant university agricultural experiment stations. IR-4 is a partnership between agricultural producers, land grant universities, government, and chemical manufacturers. Today, IR-4 conducts research on chemical and biological pest controls. Virginia Tech pest management faculty are active in the IR-4 Project. This involves the indentification of grower needs for pest controls to maintain their minor crops (64% of Virginia crops are minor crops) and research to support the registration of chemical and biological pesticides and animal drugs.
  
  
• Virginia Pest Management Information Program (VPMIP) → website
  The Virginia Pest Management Information Program (VPMIP) is the Virginia component of the Southern IPM Center. VPMIP was originally part of the USDA National Agricultural Pesticide Impact Assessment Program (NAPIAP) established in 1977 to collect pesticide benefit use data for EPA's Office of Pesticide Programs and the USDA Office of Pest Management Policy. PIAP was a joint effort of USDA and the state Land-Grant University - Agricultural Experiment Stations and Cooperative Extension Services. The Southern IPM Center was established at North Carolina State University in 2003. The program is funded by the IPM Center through grants supporting a "Virginia State Contact Project (SCP)" and collaboration with stakeholders through the development of crop pest management profiles and pest management strategic plans.
  
  
• Virginia Pesticide Safety Education Program → website
  Pesticide Safety Education (PSE) in Virginia is a statewide educational program with an overall goal to protect the environment and the public health from improper pesticide use through applicator and public education. The primary target audience includes certified and non-certified pesticide applicators of all kinds, farmworkers, and the general public. Most of the program activity involves training support for a group of approximately 21,000 pesticide applicators who seek training in order to comply with federal and state pesticide certification and licensing requirements. Program efforts are coordinated with other states, state and federal pesticide regulatory agencies, agricultural organizations, manufacturers of pesticide chemicals and alternative control technology, application equipment and engineering control companies, and other related cooperators. The program is supported by Extension agents and specialists from across the Commonwealth. In 2004, Extension agents from over 90 Virginia localities dedicated their time and resources to this program. That group is responsible for holding over 300 annual training meetings and field days designed to benefit pesticide applicators across Virginia and the region. The agents train applicators, develop training media and programs, answer public inquiries, and advise the public on proper and safe pesticide use and the selection of proper pest management strategies including non-chemical alternatives to pesticides.
  
  
• West African Regional Consortium of IPM Excellence
  This project is part of a USAID funded Integrated Pest Management CRSP that seeks to develop regional IPM programs in West Africa. It involves five African countries including: Burkina Faso, Gambia, Guinea, Mali, Senegal and multiple institutions in these countries and the US.
  
  
• West Nile Virus Surveillance
  West Nile virus is a mosquito-borne disease that is normally found in Africa, West Asia and the Middle East. However, an outbreak of West Nile virus in the New York City metropolitan area in the late summer of 1999 resulted in over 60 confirmed human infections with 7 deaths.This is the first time that West Nile virus has been found in the Western hemisphere. In response to the introduction of this new virus threat, the Virginia Interagency Arbovirus Task Force was formed in December 1999.
  
  
• Heat-shock response in disease vector mosquitoes
  Studies of Aedes aegypti have shown that heat shock stress affects the susceptibility of the mosquitoes to arboviruses. These studies have included testing whole organism susceptibility and cell culture studies. Stress response can be induced not only by heat but also by chemicals and viral infection. It is not known whether the induction of heat shock proteins helps viral proliferation by folding packaging proteins or if it takes a defensive role against the virus. Understanding the induction of heat shock protein expression may lead to a better understanding of the interaction between stress response and viral infection in disease vector mosquitoes.