Source: NORTH CAROLINA STATE UNIV submitted to NRP
INSECT-SPECIFIC TARGET SYSTEMS FOR THE DEVELOPMENT OF NOVEL TOOLS FOR COCKROACH CONTROL
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
0168824
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Oct 1, 2012
Project End Date
Sep 30, 2017
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
NORTH CAROLINA STATE UNIV
(N/A)
RALEIGH,NC 27695
Performing Department
Entomology
Non Technical Summary
Insects account for tremendous losses of food and fiber and many, including cockroaches, acquire, carry, and transfer human pathogens. This has led to extensive use of insecticides for pest control. The utilization of broad spectrum toxins for cockroach control has resulted in environmental and public health concerns and insecticide resistance and has created a need for the continued development of safe, effective, and environmentally compatible insect control techniques. The relatively specific functions of certain organs and metabolic processes in insects have provided focal points for studies leading to the discovery of selective agents for insect control. Toward this end, this proposal addresses major insect-specific target organs/systems and highly species-specific biological control agents. We also propose to further our fundamental understanding of cockroach-produced allergens and both cockroach and allergen mitigation strategies. The German cockroach is a major urban worldwide pest; it is usually the most prominent and therefore most important of the household cockroaches. It poses both direct and indirect hazards to humans and animals as producers of allergens and as significant agents in the transmission of antibiotic resistant microbes in livestock production systems. Alternative approaches for cockroach control are therefore needed and it is essential that safe, effective, and environmentally compatible insect control techniques be developed and incorporated into sustainable IPM programs. Our research is committed to understanding basic aspects of the population genetics of cockroaches so that decision-making in the urban and agricultural environment is vastly improved.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
7215320113030%
7215399113030%
8045320113010%
8045399113010%
7235320113010%
7235399113010%
Knowledge Area
804 - Human Environmental Issues Concerning Apparel, Textiles, and Residential and Commercial Structures; 723 - Hazards to Human Health and Safety; 721 - Insects and Other Pests Affecting Humans;

Subject Of Investigation
5399 - Structures, facilities, and equipment, general/other; 5320 - Houses (human residences), furniture, household equipment, non-textile furnishings;

Field Of Science
1130 - Entomology and acarology;
Goals / Objectives
Long-Term Goals: We propose to develop and incorporate effective and environmentally compatible pest management tactics into Integrated Pest Management programs for Urban ecosystems. We will conduct a two pronged approach: (a) Basic research on the chemical communication system of cockroaches, allergens they produce and viruses that infect them will result in the isolation, assay, identification, and synthesis of pheromones that are needed for the development of better pest management practices and effective, species-specific biological control agents; (b) Laboratory and field studies will evaluate the utility of these compounds and biological control agents for integrated cockroach management. Furthermore, we will investigate innovative approaches to reduce cockroach populations and the allergens associated with them. Specific Objectives: 1. Identify the complete blend of the volatile sex pheromone of the German cockroach. 2. Determine the sites of expression and function of cockroach-produced allergens. 3. Gain a comprehensive understanding of the pathology and molecular ecology of a newly discovered Blattella germanica densovirus. 4. Evaluate various cockroach control procedures and transfer new technology to the pest control industry.
Project Methods
1. Identify the complete blend of the volatile sex pheromone of the German cockroach. Following the same procedure that we used for purification of blattellaquinone the extract is passed through a short silica gel column and eluted with solvents of increasing polarity. Pheromone activity is monitored by behavioral assays and by EAG. The active fractions are then concentrated and chromatographed on a non-polar macro-bore GLC column. Eluted compounds are tested by continuous GLC-EAD or collected at short intervals. The collected fractions are then tested by behavioral and EAG assays, and the active material amassed for analytical and micro-chemical reactions. Further separations are then done on higher resolution analytical columns. When sufficient material is accumulated, we will obtain high resolution mass spectra, including EI and CI, infra-red (FT-IR), NMR, and UV spectra, and perform microchemical reactions. Final confirmation will be done by synthesis of active compounds and dose-response behavioral studies comparing it to the natural material. 2. Determine the sites of expression and functions of cockroach-produced allergens. The anatomical tissue distribution of Bla g 1, 2, 4, and 5 will be examined in nymphs and adult males and females of the German cockroach using ELISA, immunohistochemistry, Northern blots, real time-qPCR, and in situ RNA hybridization. RNAi approaches have worked well in this cockroach and we have silenced expression of Bla g 1. 3. Gain a comprehensive understanding of the pathology and molecular ecology of a newly discovered Blattella germanica densovirus. We will collect cockroaches from various localities, and use our previously described DNA extraction protocol, and PCR procedures. If an additional DNA band of ~5 kb is revealed, this band will be excised and subjected to restriction digests to determine if it corresponds to BgDNV. To describe the species-specificity and host range of the virus healthy cockroaches of different genera and species will be infected with virus isolated from infected B. germanica or cell culture. DNA will be extracted from injected animals and checked for the presence of the additional band corresponding to BgDNV on agarose gels. The physiological and behavior status of the injected animals will be followed in order to detect manifestations of virus pathology. 4. Evaluate various cockroach control procedures and their effect on cockroach allergen load in structures. The cockroach populations in infested residences will be estimated with sticky traps placed overnight in the kitchen, bathroom, living room, and one bed room. Homes will be assigned randomly to one of 3 treatments: untreated control, whole-home treatment, and only kitchen and bathroom treated.

Progress 10/01/15 to 09/30/16

Outputs
Target Audience:Academic scientists, pest control operators, municipalities, livestock production managers, allergy clinicians Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?5 postdocs, 1 professional scientist, 2 visiting professors, 11 graduate students and 4 undergraduates were trained. How have the results been disseminated to communities of interest?Two meetings of the North Carolina Pest Control Association Education Committee. Three days of attending and lecturing at the North Carolina Pest Management Association Pest Control Technicians School. Presentations on research updates from NCSU to Pest Management Professionals. Presentations on bed bug research to Pest Management Professionals. Presentations (2) at the Mid-Atlantic Pest Management Conference. Presentations on bed bug personal protection at regional pest control workshops. Numerous (ca. 50) calls from consumers and industry regarding household pests. About 10 interviews with local, national and international media regarding urban pests. Various Outreach activities, including Entomology demonstration at NC State College of Agriculture and Life Sciences (CALS) Alumni Tailgate, BugFest, Schiele Museum Bugapalooza (Gastonia, NC), Science of Attraction (Museum of Life & Science, Durham, NC), IMSD Ambassador Project: Chesterbrook Academy 3rd grade students, Judge for State 4-H Competition - "Bugs and Bees" category (Raleigh, NC) Media: Link NCSUWashington PostBusiness InsiderGenome WebU.S. News & World ReportThe New YorkerThe Australian EurekaAlert What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Adaptations to hazardous environmental factors are essential for survival, although they may be maladaptive in conditions where the hazard is absent. In German cockroach (Blattella germanica L.) populations, glucose aversion has evolved rapidly in response to glucose-containing insecticidal baits, but little is known about the consequences of this behaviour in the absence of bait. In our study, glucose-averse (GA) and wild-type (WT) male German cockroaches are restricted to a range of nutritionally defined diets containing either glucose or fructose as the sole carbohydrate source, and time to first expression of courtship is measured by stimulating the male antennae daily with isolated antennae from receptive, 6-day-old females. Glucose-averse males that are restricted to glucose-containing diets mature their courtship responses significantly later than GA males restricted to fructose-containing diets, whereas there is no difference in maturation of courtship responses between GA males restricted to fructose-containing diets and WT males restricted to diets containing either sugar type. Glucose-averse males furthermore respond later to GA female antennae than to WT female antennae, all from 6-day-old females. This suggests that GA females are less sexually stimulating, and the results are also consistent with earlier findings showing that GA females contain less developed oocytes than WT females at this age. These findings demonstrate that an adaptive gustatory mutation conferring protection from a toxin may have comparatively detrimental effects under conditions where the toxin has vanished, both by delaying female sexual maturation and signaling and by delaying male sexual maturation and courtship under conditions where glucose is a major energy source. Bait formulations are considered to be the most effective method for reducing German cockroach (Blattella germanica) infestations. An important property of some bait formulations is secondary kill, whereby active ingredient (AI) is translocated in insect-produced residues throughout the cockroach population, especially affecting relatively sedentary early-instar nymphs. B. germanica was collected from a location where baits containing hydramethylnon, fipronil or indoxacarb had become ineffective, and these AIs were topically applied to adult males. Results revealed the first evidence for hydramethylnon resistance, moderate resistance to fipronil and extremely high resistance to indoxacarb. Insecticide residues excreted by field-collected males that had ingested commercial baits effectively killed nymphs of an insecticide-susceptible laboratory strain of B. germanica but failed to kill most nymphs of the field-collected strain. We reported three novel findings: (1) the first evidence for hydramethylnon resistance in any insect; (2) extremely high levels of indoxacarb resistance in a field population; (3) reduced secondary mortality in an insecticide-resistant field-collected strain of B. germanica. We suggest that, while secondary mortality is considered to be advantageous in cockroach interventions, the ingestion of sublethal doses of AI by nymphs may select for high insecticide resistance by increasing the frequency of AI resistance alleles within the population. Bait formulations are widely used to control German cockroach (Blattella germanica) populations. To perform optimally, these formulations must compete favorably with non-toxic alternative foods present within the insect's habitat. We hypothesized that the nutritional history of cockroaches and their acceptance or avoidance of glucose would affect their food preference and thus bait efficacy. To test this hypothesis, we conducted a controlled laboratory experiment, first providing glucose-accepting and glucose-averse cockroaches nutritionally defined diets and then offering them identical diets containing the insecticide hydramethylnon as a bait proxy to evaluate the effect of diets of differing macronutrient composition on bait performance. The interaction between diet composition and bait composition affected the survival of adult males as well as first-instar nymphs exposed to excretions produced by these males. Survival analyses indicated different responses of glucose-averse and glucose-accepting insects, but generally any combination of diet and bait that resulted in high diet intake and low bait intake reduced secondary kill. This study represents a comprehensive examination of the effect of alternative foods on bait efficacy. We suggest that disparities between the nutritional quality of baits and the foods that are naturally available could profoundly impact the management of German cockroach infestations. Densoviruses are a group of arthropod-infecting viruses with a small single-stranded linear DNA genome. These viruses constitute the subfamily Densovirinae of the family Parvoviridae. While recombination in between vertebrate-infecting parvoviruses has been investigated, to date, no systematic analysis of recombination has been carried out for densoviruses. The aim of the present work was to study possible recombination events in the evolutionary history of densoviruses and to assess possible effects of recombination on phylogenies inferred using amino acid sequences of nonstructural (NS) and capsid (viral protein, VP) proteins. For this purpose, the complete or nearly complete genome nucleotide sequences of 40 densoviruses from the GenBank database were used to construct a phylogenetic cladogram. The viruses under study clustered into five distinct groups corresponding to the five currently accepted genera. Recombination within each group was studied independently. The RDP4 software revealed three statistically highly credible recombination events, two of which involved viruses of the genus Ambidensovirus, and the other, viruses from the genus Iteradensovirus. These recombination events led to mismatches between phylogenetic trees constructed using comparison of amino acid sequences of proteins encoded by genome regions of recombinant and non-recombinant origin (regulatory NS1 and NS3 proteins and capsid VP protein). The Asian cockroach (Blattella asahinai Mizukubo) was introduced to Florida in 1986 and has since spread throughout the Southeastern United States. Blattella asahinai is a peridomestic pest and high population densities in residential areas can become a nuisance, especially when adults fly into homes. Few studies to date have been conducted on Asian cockroach control, and we evaluated the efficacy of Zyrox Fly Granular Bait and Maxforce Complete Granular Insect Bait against this species in the laboratory compared with the closely related German cockroach (Blattella germanica (L.)). In no-choice and two-choice assays with both species, Zyrox bait and Maxforce bait achieved nearly 100% mortality within two and five days, respectively. We also tested Zyrox bait against B. asahinai in an invasive field population in North Carolina at the label rate (2 g/sq m) and at approximately three times the label rate (6.9 g/ sq m), and found that broadcast applications at both rates reduced populations by an average of 64 and 92%, respectively, for 35 d after the initial application. Zyrox Fly Bait appears to be effective against the Asian and German cockroaches, and could be another tool in an integrated pest management program, if its label could be extended or the active ingredient (cyantraniliprole) formulated into a cockroach bait.

Publications

  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Jensen K., A. E. Ko, C. Schal and J. Silverman. 2016. Insecticide resistance and nutrition interactively shape life-history parameters in German cockroaches. Scientific Reports 6, 28731. doi: 10.1038/srep28731
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Ko A. E., D. N. Bieman, C. Schal and J. Silverman. 2016. Insecticide resistance and diminished secondary kill performance of bait formulations against German cockroaches (Dictyoptera: Blattellidae). Pest Management Science 72: 17781784. doi: 10.1002/ps.4211
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Ko A. E., C. Schal and J. Silverman. 2016. Diet quality affects bait performance in German cockroaches (Dictyoptera: Blattellidae). Pest Management Science 72: 18261836 doi: 10.1002/ps.4295
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Kolokotronis S-O., J. Foox, J. A. Rosenfeld, M. R. Brugler, D. Reeves, J. B. Benoit, W. Booth, G. Robison, M. Steffen, S. R. Palli, C. Schal, S. Richards, A. Narechania, R. H. Baker, L. N. Sorkin, G. Amato, C. E. Mason, M. E. Siddall, R. DeSalle and Z. Sakas. 2016. The mitogenome of the bed bug Cimex lectularius (Hemiptera: Cimicidae). Mitochondrial DNA Part B: Resources 1(1): 425427. doi: 10.1080/23802359.2016.1180268
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Martynova E. U., C. Schal and D. V. Mukha. 2016. Effects of recombination on Densovirus phylogeny. Archives of Virology 161: 6375. doi: 10.1007/s00705-015-2642-5
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Matos Y. and C. Schal. 2016. Laboratory and field evaluation of Zyrox Fly Granular Bait against Asian and German cockroaches (Dictyoptera: Blattellidae). Journal of Economic Entomology 109: 18071812. doi: 10.1093/jee/tow092
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Paz-Soldan V. A., J. Yukich, A. Soonthorndhada, M. Giron, C. S. Apperson, L. Ponnusamy, C. Schal, A. C. Morrison, J. Keating and D. M. Wesson. 2016. Design and testing of novel lethal ovitrap to reduce populations of Aedes mosquitoes: community-based participatory research between industry, academia and communities in Peru and Thailand. PLoS ONE 11(8): e0160386. doi: 10.1371/journal.pone.0160386
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Raab R. W., J. E. Moore, E. L. Vargo, L. Rose, J. Raab, M. Culbreth, G. Burzumato, A. Koyee, B. McCarthy, J. Raffaele, C. Schal and R. Vaidyanathan. 2016. New introductions, spread of existing matrilines, and high rates of pyrethroid resistance result in chronic infestations of bed bugs (Cimex lectularius L.) in lower income housing. PLoS ONE 11(2): e0117805. doi: 10.1371/journal.pone.0117805
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Rangel J., K. B�r�czky, C. Schal and D. R. Tarpy. 2016. Honey bee (Apis mellifera) queen reproductive potential affects queen mandibular gland pheromone composition and worker retinue response. PLoS ONE 11(6): e0156027. doi: 10.1371/journal.pone.0156027
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Shorter J. R., L. M. Dembeck, L. J. Everett, T. V. Morozova, G. H. Arya, L. Turlapati, G. E. St. Armour, C. Schal, T. F. C. Mackay and R. R. H. Anholt. 2016. Obp56h modulates mating behavior in Drosophila melanogaster. G3: Genes, Genomes, Genetics 6: 3335-3342. doi: 10.1534/g3.116.034595
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Wang F-M., J-Y. Deng, C. Schal, Y-G. Lou, G-X. Zhou, B-B. Ye, X-H. Yin, Z-H. Xu and L-Z. Shen. 2016. Non-host plant volatiles disrupt sex pheromone communication in a specialist herbivore. Scientific Reports 6, 32666. doi: 10.1038/srep32666
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Choi D. B., J. P. Grieco, C. S. Apperson, C. Schal, L. Ponnusamy, D. M. Wesson and N. L. Achee. 2016. Effect of spatial repellent exposure on dengue vector attraction to oviposition sites. PLoS Neglected Tropical Diseases 10(7): e0004850. doi: 10.1371/journal.pntd.0004850.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Jensen K., C. Schal and J. Silverman. 2016. Gustatory adaptation affects sexual maturation in male German cockroaches, Blattella germanica. Physiological Entomology 4: 1923. doi: 10.1111/phen.12122
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Benoit J. B., Z. N. Adelman, K. Reinhardt, A. Dolan, M. Poelchau, E. C. Jennings, E. M. Szuter, R. W. Hagan, H. Gujar, J. Shukla, F. Zhu, M. Mohan, D. R. Nelson, A. J. Rosendale, C. Derst, V. Resnik, S. Wernig, P. Menegazzi, C. Wegener, N. Peschel, J. M. Hendershot, W. Blenau, R. Predel, P. R. Johnston, P. Ioannidis, R. M. Waterhouse, R. Nauen, C. Schorn, M.-C. Ott, F. Maiwald, J. S. Johnston, A. D. Gondhalekar, M. E. Scharf, B. F. Peterson, K. R. Raje, B. A. Hottel, D. Armis�n, A. J. Johan Crumi�re, P. N. Refki, M. E. Santos, E. Sghaier, S. Viala, A. Khila, S.-J. Ahn, C. Childers, C.-Y. Lee, H. Lin, D. S. T. Hughes, E. J. Duncan, S. C. Murali, J. Qu, S. Dugan, S. L. Lee, H. Chao, H. Dinh, Y. Han, H. Doddapaneni, K. C. Worley, D. M. Muzny, D. Wheeler, K. A. Panfilio, I. M. Vargas Jentzsch, E. L. Vargo, W. Booth, M. Friedrich, M. L. Porter, J. W. Jones, O. Mittapalli, C. Zhao, J.-J. Zhou, J. D. Evans, G. M. Attardo, H. M. Robertson, E. M. Zdobnov, J. M.C. Ribeiro, R. A. Gibbs, J. H. Werren, S. R. Palli, C. Schal and S. Richards. 2016. Unique features of the bed bug, a global human ectoparasite, identified through genome sequencing. Nature Communications 7: 10165. doi: 10.1038/ncomms10165


Progress 10/01/14 to 09/30/15

Outputs
Target Audience:Academic scientists, pest control operators, municipalities, livestock production managers, allergy clinicians Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?7 postdocs, 1 professional scientist, 2 visiting professors, 11graduate students and 4 undergraduates were trained. How have the results been disseminated to communities of interest?Two meetings of the North Carolina Pest Control Association Education Committee. Three days of attending and lecturing at the North Carolina Pest Management Association Pest Control Technicians School. Presentations on research updates from NCSU to Pest Management Professionals. Presentations on bed bug research to Pest Management Professionals. Presentations (2) at the Mid-Atlantic Pest Management Conference. Presentations on bed bug personal protection at regional pest control workshops. Numerous (ca. 50) calls from consumers and industry regarding household pests. About 10 interviews with local, national and international media regarding urban pests. Various Outreach activities, including Entomology demonstration at NC State College of Agriculture and Life Sciences (CALS) Alumni Tailgate, BugFest, Schiele Museum Bugapalooza (Gastonia, NC), Science of Attraction (Museum of Life & Science, Durham, NC), IMSD Ambassador Project: Chesterbrook Academy 3rd grade students, Judge for State 4-H Competition - "Bugs and Bees" category (Raleigh, NC) Media: German Public Radio http://www.deutschlandfunk.de/insektenforschung-der-duft-der-schaben.676.de.html?dram:article_id=339166 Smithsonian http://www.smithsonianmag.com/science-nature/scent-their-own-poop-entices-cockroaches-congregate-180957471/?no-ist Science http://news.sciencemag.org/plants-animals/2015/12/cockroaches-communicate-bacteria-their-feces http://phys.org/news/2015-12-gut-bacteria-important-factor-cockroach.html Scientific American http://www.scientificamerican.com/podcast/episode/cockroach-caca-contains-chemical-messages-made-by-microbes/ Science Codex http://www.sciencecodex.com/gut_bacteria_important_factor_in_cockroach_gathering-171285 EurekaAlert http://www.eurekalert.org/pub_releases/2015-12/ncsu-gbi120315.php Daily Mail http://www.dailymail.co.uk/sciencetech/article-3351631/Cockroaches-attracted-poo-companions-Gut-microbes-aggregation-pheromones.html Inverse https://www.inverse.com/article/8949-cockroaches-find-the-scent-of-bacteria-attractive The Scientist http://www.the-scientist.com/?articles.view/articleNo/44728/title/Gut-Bugs-Affect-Cockroach-Poop-ularity/ PCT http://www.pctonline.com/article/NC-State-cockroach-study-gut-bacteria Motherboard http://motherboard.vice.com/read/behold-the-cockroach-internet-of-shit-and-gut-bacteria News & Observer http://www.newsobserver.com/news/technology/article27927940.html Press Releases Gut bacteria in cockroaches paper inPNAS: https://news.ncsu.edu/2015/12/gut-bacteria-cockroach-gathering/ Five Faculty Win Holladay Medal: https://news.ncsu.edu/2015/04/2015-holladay-medal/ What do you plan to do during the next reporting period to accomplish the goals?Continue chemical ecology and epidemiology studies with the common bed bug. Continue isolation and characterization of behaviorally active compounds from bacterial species that mediate oviposition in mosquitoes (collaboration with Apperson, Wesson at Tulane). Continue investigations of the evolution of sexual communication in Heliothis moths (NSF funded, collaboration with Groot). Continue investigations of total release foggers (TRFs), which are often used in homes to kill cockroaches and bed bugs. The project empirically test the efficacy and to conduct a cost-benefit analysis of TRF products in the context of promoting reduced-risk and IPM practices in low-income households in five communities in Raleigh, NC. (HUD funded). Develop innovative, biologically-based semiochemical tools that will facilitate early detection, population monitoring, and ultimately control of Sirex noctilio (USDA-APHIS-FS funded). Continue projects on isolation and characterization of behaviorally active compounds from bacterial species that mediate oviposition in sand flies (NCBC- and NIH-funded, collaboration with Wasserberg (UNC-G), Apperson, Ponnusamy). Continue projects on isolation and characterization of behaviorally active compounds that mediate egg hatch in mosquitoes (NIH funded, collaboration with Apperson, Ponnusamy). Continue investigations of the gustatory mechanisms of glucose-aversion (collaboration with Silverman, Katsumata).

Impacts
What was accomplished under these goals? Continuing progress on developing an integrated cockroach management program in confined swine production, which includes (a) testing the efficacy of various new technologies and formulations for cockroach control; (b) and studying the environmental distribution of cockroach allergens in swine farms and approaches to reduce allergens. We also demonstrated that the German cockroach and house flies play important roles in the ecology of antibiotic resistant enterococci in confined swine production. Extensive use of antibiotics as growth promoters in the livestock industry constitutes strong selection pressure for evolution and selection of antibiotic resistant bacterial strains. We isolated, quantified, identified, and screened for antibiotic resistance and virulence Enterococci from house flies, German cockroaches and pigs. The majority of samples were positive, and showed that multi-drug resistant enterococci were common from all three sources and frequently carried antibiotic resistance genes. This study showed that house flies and German cockroaches in the confined swine production environment likely serve as vectors and/or reservoirs of antibiotic resistant and potentially virulent enterococci and consequently may play an important role in animal and public health. We demonstrate that the gut microbial community of the German cockroach contributes to production of semiochemicals that mediate aggregation. Chemical analysis of the fecal extract of B. germanica revealed 40 VCAs. Feces from axenic cockroaches (no microorganisms in the alimentary tract) lacked 12 major fecal VCAs, and 24 of the remaining compounds were represented at extremely low amounts. Olfactory and aggregation bioassays demonstrated that nymphs strongly preferred the extract of control feces over the fecal extract of axenic cockroaches. Additionally, nymphs preferred a synthetic blend of 6 fecal VCAs over a solvent control or a previously identified VCA blend. To test whether gut bacteria contribute to the production of fecal aggregation agents, fecal aerobic bacteria were cultured, isolated, and identified. Inoculation of axenic cockroaches with individual bacterial taxa significantly rescued the aggregation response to the fecal extract, and inoculation with a mix of six bacterial isolates was more effective than with single isolates. The results indicate that the commensal gut microbiota contributes to production of VCAs that act as fecal aggregation agents and that cockroaches discriminate among the complex odors that emanate from a diverse microbial community. Our results highlight the pivotal role of gut bacteria in mediating insect-insect communication. Moreover, because the gut microbial community reflects the local environment, local plasticity in fecal aggregation pheromones enables colony-specific odors and fidelity to persistent aggregation sites. As part of a project to measure and document the effects and impacts on the environment and human health of using total release foggers (TRFs) and to compare these with the effects and impacts of using reduced-risk gel baits within an IPM program, we have initiated studies of pyrethroid resistance in cockroaches. We found extensive and high levels of resistance in Raleigh populations of cockroaches. Showed that C. lectularius that associate with humans have a cosmopolitan distribution, whereas those associated with bats occur across Europe, often in human-built structures. We assessed genetic structure and gene flow within and among populations collected in association with each host using mtDNA, microsatellite loci and knock-down resistance gene variants. Both nuclear and mitochondrial data support a lack of significant contemporary gene flow between host-specific populations. Within locations human-associated bed bug populations exhibit limited genetic diversity and elevated levels of inbreeding, likely due to human-mediated movement, infrequent additional introduction events per infestation, and pest control. In contrast, populations within bat roosts exhibit higher genetic diversity and lower levels of relatedness, suggesting populations are stable with temporal fluctuations due to host dispersal and bug mortality. In concert with previously published evidence of morphological and behavioral differentiation, the genetic data presented here suggest C. lectularius is currently undergoing lineage divergence through host association. We documented frequent mtDNA heteroplasmy in the bed bug. Our findings show that heteroplasmy is common, with 5 of 29 (17%) populations screened exhibiting two mitochondrial variants within each individual. We hypothesized that the mechanism underlying heteroplasmy in bed bugs is paternal leakage because some haplotypes were shared among unrelated populations and no evidence for nuclear mitochondrial DNA sequences was detected. Isolated and in the process of characterizing behaviorally active compounds from bacterial species that mediate oviposition in mosquitoes. We identified several semiochemicals that attract mosquitoes to plant infusions, and other chemicals that stimulate gravid females to lay their eggs in water. These compounds have great potential as components of monitoring traps and in lethal ovitraps that target gravid (and potentially virus-infected) mosquitoes. We are making good progress on a project on the pre-mating reproductive isolating signals of moth species with emphasis on male close-range signaling. We also assessed the heritability, genetic basis and behavioral consequences of pheromone variation in the field. Artificial selection with field-collected moths dramatically changed the pheromone composition. Continuing studies on cuticular hydrocarbons and contact sex pheromone of the German cockroach and the involvement of contact pheromones in chemical sexual mimicry. This system has become, arguably, the best known contact pheromone system from the integrated perspective of chemical complexity, biosynthetic pathways, hormonal control, and roles in behavior. We delineated the behavioral resistance mechanism of sugar-aversion in the German cockroach in several populations of cockroaches. We have conducted extensive behavioral and electrophysiological assays to show that alterations in the peripheral gustatory system are responsible for this behavior. We have initiated molecular genetic studies. Ayako Wada-Katsumata (senior research scholar) is conducting this project. We used feeding experiments within the geometric framework to test whether glucose-averse cockroaches with limited access to glucose have compensatory behavioral and physiological strategies for meeting nutritional requirements. Glucose-averse cockroaches had severely constrained food intake, fat and N mass, and performance on glucose-based diets relative to wild type cockroaches and did not appear to exhibit digestive strategies for retaining under-eaten nutrients. However, we found that hybrids may be a reservoir for this maladaptive trait in the absence of positive selection and may account for the rapid evolution of this trait following bait application.

Publications

  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Booth W., O. Balvin, E. L. Vargo, J. Vil�mov� and C. Schal. 2015. Host association drives genetic divergence in the bed bug, Cimex lectularius. Molecular Ecology 24: 980992. doi: 10.1111/mec.13086.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Dembeck L. M., K. B�r�czky, W. Huang, C. Schal, R. R. H. Anholt and T. F. C. Mackay. 2015. Genetic architecture of natural variation in cuticular hydrocarbon composition in Drosophila melanogaster. eLife 4:e09861. doi: 10.7554/eLife.09861.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Wada-Katsumata A., J. Silverman and C. Schal. 2015. Sugar aversion: A newly-acquired adaptive change in gustatory receptor neurons in the German cockroach. Japanese Society for Comparative Physiology and Biochemistry 31: 220230.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Jensen K., C. Schal and J. Silverman. 2015. Adaptive contraction of diet breadth affects sexual maturation and specific nutrient consumption in an extreme generalist omnivore. Journal of Evolutionary Biology 28: 906916. doi: 10.1111/jeb.12617
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Jensen K., C. Schal and J. Silverman. 2015. Suboptimal nutrient balancing despite dietary choice in glucose-averse German cockroaches, Blattella germanica. Journal of Insect Physiology 81: 4247. doi: 10.1016/j.jinsphys.2015.07.001
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Marayati B. F., C. Schal, L. Ponnusamy, C. S. Apperson, T. Rowland and G. Wasserberg. 2015. Attraction and oviposition preferences of Phlebotomus papatasi, vector of Old-World cutaneous leishmaniases, to larval rearing media. Parasites and Vectors 8: 663. doi: 10.1186/s13071-015-1261-z
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: 225. Martin L. J., R. Adams, A. Bateman, H. M. Bik, S. Crane, L. Fellman, S. M. Hird, D. Hughes, S. W. Kembel, K. Kinney, S.-O. Kolokotronis, G. Levy, C. McClain, J. F. Meadow, R. F. Medina, G. Mhuireach, C. S. Moreau, J. Munshi-South, C. Palmer, L. Popova, C. Schal, J. Siegel, M. T�ubel, M. Trautwein, J. A. Ugalde, W. Wilson and R. R. Dunn. 2015. Evolution on the indoor biome. Trends in Ecology and Evolution 30: 223232 doi: 10.1016/j.tree.2015.02.001
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Matos Y. K. and C. Schal. 2015. Electroantennogram responses and field trapping of Asian cockroach (Dictyoptera: Blattellidae) with blattellaquinone, sex pheromone of the German cockroach (Dictyoptera: Blattellidae). Environmental Entomology 44: 11551160. doi: 10.1093/ee/nvv090
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Ponnusamy, K., C. Schal, D. M. Wesson, C. Arellano and C. S. Apperson. 2015. Oviposition responses of Aedes mosquitoes to bacterial isolates from attractive bamboo infusions. Parasites and Vectors 8: 486 doi: 10.1186/s13071-015-1068-y
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Robison G. A., O. Balvin, C. Schal, E. L. Vargo and W. Booth. 2015. Extensive mitochondrial heteroplasmy in natural populations of a resurging human pest, the bed bug (Hemiptera: Cimicidae). Journal of Medical Entomology 52: 734738. doi: 10.1093/jme/tjv055
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Wada-Katsumata A, L. Zurek, G. Nalyanya, W. L. Roelofs, A. Zhang and C. Schal. 2015. Gut bacteria mediate aggregation in the German cockroach. Proceedings of the National Academy of Sciences, USA 112: 1567815683. doi: 10.1073/pnas.1504031112


Progress 10/01/13 to 09/30/14

Outputs
Target Audience:Academic scientists, pest control operators, municipalities, livestock production managers, allergy clinicians Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?7 postdocs, 1 professional scientist, 9graduate students and 4undergraduates were trained. How have the results been disseminated to communities of interest?Two meetings of the North Carolina Pest Control Association Education Committee. Three days of attending and lecturing at the North Carolina Pest Management Association Pest Control Technicians School. Presentations on research updates from NCSU to Pest Management Professionals. Presentations on bed bug research to Pest Management Professionals. Presentations (2) at the Mid-Atlantic Pest Management Conference. Presentations on bed bug personal protection at regional pest control workshops. Numerous (ca. 50) calls from consumers and industry regarding household pests. About 10 interviews with local, national and international media regarding urban pests. Various Outreach activities, including Entomology demonstration at NC State College of Agriculture and Life Sciences (CALS) Alumni Tailgate, BugFest, Schiele Museum Bugapalooza (Gastonia, NC), Science of Attraction (Museum of Life & Science, Durham, NC) A sampling of media stories: Virna Saenz (PhD student) research on bed bugs: ESA Science Daily Philly.com RedOrbit Medical Daily PR Web Ada Uzsák (PhD student) research on insect antennae: NCSU Smithsonian Entomology Today Phys.org RedOrbit Press Releases Glucose taste aversion in cockroaches paper inScience: NCSU press release Insect antennal grooming paper inProceedings of the National Academy of Sciences: NCSU press release (blog) What do you plan to do during the next reporting period to accomplish the goals?Continue chemical ecology and epidemiology studies with the common bed bug. Continue isolation and characterization of behaviorally active compounds from bacterial species that mediate oviposition in mosquitoes (collaboration with Apperson, Wesson at Tulane). Continue investigations of the evolution of sexual communication in Heliothis moths (NSF proposal, collaboration with Groot). Continue investigations of total release foggers (TRFs), which are often used in homes to kill cockroaches and bed bugs. The project empirically test the efficacy and to conduct a cost-benefit analysis of TRF products in the context of promoting reduced-risk and IPM practices in low-income households in five communities in Raleigh, NC. (HUD funded). Develop innovative, biologically-based semiochemical tools that will facilitate early detection, population monitoring, and ultimately control of Sirex noctilio (USDA-APHIS-FS funded). Continue projects on isolation and characterization of behaviorally active compounds from bacterial species that mediate oviposition in sand flies (NCBC-funded, collaboration with Wasserberg (UNC-G), Apperson, Ponnusamy). Continue projects on isolation and characterization of behaviorally active compounds that mediate egg hatch in mosquitoes (NIH funded, collaboration with Apperson, Ponnusamy). Continue investigations of the gustatory mechanisms of glucose-aversion (collaboration with Silverman, Katsumata).

Impacts
What was accomplished under these goals? Continuing progress on developing an integrated cockroach management program in confined swine production, which includes (a) testing the efficacy of various new technologies and formulations for cockroach control; (b) and studying the environmental distribution of cockroach allergens in swine farms and approaches to reduce allergens. We also demonstrated that the German cockroach and house flies play important roles in the ecology of antibiotic resistant enterococci in confined swine production. Rick Santangelo (Research Specialist) is conducting this project. Extensive use of antibiotics as growth promoters in the livestock industry constitutes strong selection pressure for evolution and selection of antibiotic resistant bacterial strains. We isolated, quantified, identified, and screened for antibiotic resistance and virulence Enterococci from house flies, German cockroaches and pigs. The majority of samples were positive, and showed that multi-drug resistant enterococci were common from all three sources and frequently carried antibiotic resistance genes. This study showed that house flies and German cockroaches in the confined swine production environment likely serve as vectors and/or reservoirs of antibiotic resistant and potentially virulent enterococci and consequently may play an important role in animal and public health. We conducted an analysis of nuclear and cytoplasmic extracts of BgDNV densovirus infected German cockroaches and investigated the intracellular localization of regulatory proteins in cell culture. We demonstrated that two proteins, NS1 and NS3, were predominantly localized in the nucleus, whereas NS2 was equally distributed in the nuclei and the cytoplasm. These results are important for understanding the potential functions of densovirus regulatory proteins. The intracellular localization of NS3 protein was determined for the first time for any densovirus. As part of a project to measure and document the effects and impacts on the environment and human health of using total release foggers (TRFs) and to compare these with the effects and impacts of using reduced-risk gel baits within an IPM program, we have initiated studies of pyrethroid resistance in cockroaches. We found extensive and high levels of resistance in Raleigh populations of cockroaches. Rick Santangelo (Research specialist) is conducting this project. We have extended the population genetic studies to bed bug populations. We have (a) perfected a rearing system based on feeding on rabbit blood with artificial membranes; (b) identified and characterized 25 polymorphic microsatellite loci and intend to recover more through 454 sequencing; (c) collected populations of bed bugs in NC, throughout the US, and globally with assistance from several major pest control companies (mainly Orkin, Cooper Pest Solutions, and JC Ehrlich); (d) extracted DNA and characterized the structure and genetic differentiation of these populations; (e) conducted DNA sequence analysis for SNPs associated with kdr-based resistance to pyrethroids; (f) conducted extensive analysis of insecticide resistance using residual and topical applications. Warren Booth, a post doctoral researcher, Virna Saenz (PhD student) and Rick Santangelo (Research specialist) are conducting this project. We used a membrane-based feeding system to identify chemicals that stimulate acceptance and engorgement responses in various life stages of bed bugs. Water was fortified with a variety of compounds (e.g. salts, amino acids, vitamins, nucleotides, cholesterol and fatty acids) in these bioassays. ATP was the most effective phagostimulant in adults and nymphs. Identification of phagostimulants for bed bugs will contribute towards the development of artificial diets for rearing purposes, as well as for the development of alternative methods to eliminate bed bug infestations. We conducted studies to determine whether bed bug nymphs reared in groups develop faster than solitary nymphs. Nymphal development was 2.2 d faster in grouped nymphs than in solitary-housed nymphs, representing 7.3% faster overall development. However, this grouping effect did not appear to be influenced by group composition. We investigated the key elements, or stimulus features, of antennal contact that socially facilitate reproduction in B. germanica females. Using motor-driven antenna mimics, we assessed the physiological responses of females to artificial tactile stimulation. Our results indicate that tactile stimulation with artificial materials, some deviating significantly from the native antennal morphology, can facilitate female reproduction. However, none of the artificial stimuli matched the effects of social interactions with a conspecific female. Isolated and in the process of characterizing behaviorally active compounds from bacterial species that mediate oviposition in mosquitoes. We identified several semiochemicals that attract mosquitoes to plant infusions, and other chemicals that stimulate gravid females to lay their eggs in water. These compounds have great potential as components of monitoring traps and in lethal ovitraps that target gravid (and potentially virus-infected) mosquitoes. Loganathan Ponnusamy and Emily Kuhns, two post doctoral researchers, are conducting this project. We are making good progress on a project on the pre-mating reproductive isolating signals of moth species with emphasis on male close-range signaling. Jeremy Heath and Michiel Van Wijk are post-doctoral researchers on this project (NSF-funded in collaboration with Groot). We also assessed the heritability, genetic basis and behavioral consequences of pheromone variation in the field. Artificial selection with field-collected moths dramatically changed the pheromone composition. Continuing studies on cuticular hydrocarbons and contact sex pheromone of the German cockroach and the involvement of contact pheromones in chemical sexual mimicry. This system has become, arguably, the best known contact pheromone system from the integrated perspective of chemical complexity, biosynthetic pathways, hormonal control, and roles in behavior. We delineated the behavioral resistance mechanism of sugar-aversion in the German cockroach in several populations of cockroaches. We have conducted extensive behavioral and electrophysiological assays to show that alterations in the peripheral gustatory system are responsible for this behavior. We have initiated molecular genetic studies. Ayako Wada-Katsumata (senior research scholar) is conducting this project. We used feeding experiments within the geometric framework to test whether glucose-averse cockroaches with limited access to glucose have compensatory behavioral and physiological strategies for meeting nutritional requirements. Glucose-averse cockroaches had severely constrained food intake, fat and N mass, and performance on glucose-based diets relative to wild type cockroaches and did not appear to exhibit digestive strategies for retaining under-eaten nutrients. However, we found that hybrids may be a reservoir for this maladaptive trait in the absence of positive selection and may account for the rapid evolution of this trait following bait application.

Publications

  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Groot A. T., G. Sch�fl, O. Inglis, S. Donnerhacke, A. Classen, A. Schmalz, R. G. Santangelo, J. Emerson, F. Gould, C. Schal and D. G. Heckel. 2014. Within-population variability in a moth sex pheromone blend: genetic basis and behavioural consequences. Proceedings of the Royal Society B: Biological Sciences 281 (1779):20133054. doi: 10.1098/rspb.2013.3054.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Martynova E. U., T. V. Kapelinskaya, C. Schal and D. V. Mukha. 2014. Intracellular localization of regulatory proteins of the German cockroach Blattella germanica densovirus. Molecular Biology 48: 301304.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Romero A. and C. Schal. 2014. Blood constituents as phagostimulants for the bed bug, Cimex lectularius L. Journal of Experimental Biology 217: 552557.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Saenz V. L., R. G. Santangelo, E. L. Vargo and C. Schal. 2014. Group-living accelerates bed bug (Hemiptera: Cimicidae) development. Journal of Medical Entomology 51: 293295.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Shik J. Z., C. Schal, and J. Silverman. 2014. Diet specialization in an extreme omnivore: nutritional regulation in glucose-averse German cockroaches. Journal of Evolutionary Biology 27: 20962105. doi: 10.1111/jeb.12458.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Vargo E. L., J. R. Crissman, W. Booth, R. G. Santangelo, D. V. Mukha and C. Schal. 2014. Hierarchical genetic analysis of German cockroach (Blattella germanica) populations from within buildings to across continents. PLoS ONE 9(7): e102321. doi:10.1371/journal.pone.0102321.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Uzs�k A., J. Dieffenderfer, A. Bozkurt and C. Schal. 2014. Social facilitation of insect reproduction with motor-driven tactile stimuli. Proceedings of the Royal Society B: Biological Sciences 281 (1783):20140325. doi: 10.1098/rspb.2014.0325.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Wada-Katsumata A., J. Silverman and C. Schal. 2015. Sugar aversion: A newly-acquired adaptive change in gustatory receptor neurons in the German cockroach. Japanese Society for Comparative Physiology and Biochemistry 31: 220230.


Progress 10/01/12 to 09/30/13

Outputs
Target Audience:Academic scientists, pest control operators, municipalities, livestock production managers, allergy clinicians Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?7 postdocs, 1 professional scientist, 6 graduate students and 2 undergraduates were trained. How have the results been disseminated to communities of interest?Civic, educational or other similar events: Two meetings of the North Carolina Pest Control Association Education Committee. Three days of attending and lecturing at the North Carolina Pest Management Association Pest Control Technicians School. Presentations on research updates from NCSU to Pest Management Professionals. Presentations on bed bug research to Pest Management Professionals. Presentations (2) at the Mid-Atlantic Pest Management Conference. Presentations on bed bug personal protection at regional pest control workshops. Numerous visits to swine facilities to remedy cockroach problems. Numerous (ca. 50) calls from consumers and industry regarding household pests. About 20 interviews with local, national and international media regarding urban pests. Various Outreach activities, including Entomology demonstration at NC State College of Agriculture and Life Sciences (CALS) Alumni Tailgate, BugFest, Schiele Museum Bugapalooza (Gastonia, NC) Extension publications Schal C. 2012. North Carolina State University research update--Cockroaches. Pest Management Professional January 2012, 31,66. Media appearances: A sampling of media stories: Ann Carr's research on ticks featured inPerspectives Glucose taste aversion in cockroaches paper inScience: NCSU press release Science Podcast(start at 10:10 min) NY Times Error! Hyperlink reference not valid. BBC(narrated video) The Scientist Pest Control Technology Podcast News &Observer NPR The Christian Science Monitor Daily Mail The Why Files Science News TIME Los Angeles Times Bloomberg News New Scientist LiveScience.com io9 J Gen Physiol Mallis Expert Insights:Q&A with Dr. Coby Schal Coby Schal profiled inPest Management Professionalmagazine Coby Schal interviewed by Terry & Joe Graedon on NPR's thePeople's Pharmacy Ada Uzsák (PhD student) awarded theKenneth R. Keller Award for Excellence in Doctoral Dissertation Research Coby Schal comments about insect personality inPest Control Technologymagazine Ada Uzsák's poster wins at the 8th AnnualNCSU Graduate Student Research Symposium Insect antennal grooming paper inProceedings of the National Academy of Sciences: NCSU press release (blog) NPR Science Friday Video Pick of the Week (Audio) (video) Discovery Channel:Why do animals groom? Science Magazine (PDF file) Today's Science (Science news for students) (PDFfile) News & Observer WUNC91.5 BBC News Science daily LiveScience.com Chemical & Engineering News Discover Magazine Science360.gov Smithsonian Magazine Discovery News SigmaXi Smart Briefs National Geographic 4 Kids Huffington Post Neuroscience News PCT Magazine Coby Schal profiled inThe Scientist Magazine Daily Planet TV show filming for an upcoming episode Press Releases Glucose taste aversion in cockroaches paper inScience: NCSU press release Insect antennal grooming paper inProceedings of the National Academy of Sciences: NCSU press release (blog) What do you plan to do during the next reporting period to accomplish the goals?Continue chemical ecology and epidemiology studies with the common bed bug. Continue isolation and characterization of behaviorally active compounds from bacterial species that mediate oviposition in mosquitoes (Gates Foundation, collaboration with Apperson, Wesson at Tulane). Continue investigations of the evolution of sexual communication in Heliothis moths (NSF proposal funded, collaboration with Groot). Continue investigations of total release foggers (TRFs), which are often used in homes to kill cockroaches and bed bugs. The project empirically test the efficacy and to conduct a cost-benefit analysis of TRF products in the context of promoting reduced-risk and IPM practices in low-income households in five communities in Raleigh, NC. (HUD funded). Develop innovative, biologically-based semiochemical tools that will facilitate early detection, population monitoring, and ultimately control of Sirex noctilio (USDA-APHIS-FS funded). Continue projects on isolation and characterization of behaviorally active compounds from bacterial species that mediate oviposition in sand flies (NCBC-funded, collaboration with Wasserberg (UNC-G), Apperson, Ponnusamy). Continue projects on isolation and characterization of behaviorally active compounds that mediate egg hatch in mosquitoes (NIH funded, collaboration with Apperson, Ponnusamy). Continue investigations of the gustatory mechanisms of glucose-aversion (collaboration with Silverman, Katsumata).

Impacts
What was accomplished under these goals? As part of our efforts to understand the chemical ecology of cockroaches, we used field emission gun scanning electron microscopy imaging and GC-MS to show that nongroomed cockroach antennae accumulated significantly more native cuticular hydrocarbons and environmental contaminants from surfaces and from air than groomed antennae. Electroantennogram experiments and single-sensillum recordings showed that antennae that were prevented from being groomed were significantly less responsive than groomed antennae to sex pheromone and to general odorants. Therefore antennal grooming maintains the olfactory acuity of the antennae. Katalin Böröczky and Ayako Wada-Katsumata (post doctoral researchers) conducted this research in collaboration with Dale Bachelor (NCSU engineering) and Marianna Zhukovskaya (Russia). Continuing progress on developing an integrated cockroach management program in confined swine production, which includes (a) testing the efficacy of various new technologies and formulations for cockroach control; (b) and studying the environmental distribution of cockroach allergens in swine farms and approaches to reduce allergens. We also demonstrated that the German cockroach and house flies play important roles in the ecology of antibiotic resistant enterococci in confined swine production. Rick Santangelo (Research Specialist) is conducting this project. Extensive use of antibiotics as growth promoters in the livestock industry constitutes strong selection pressure for evolution and selection of antibiotic resistant bacterial strains. We isolated, quantified, identified, and screened for antibiotic resistance and virulence Enterococci from house flies, German cockroaches and pigs. The majority of samples were positive, and showed that multi-drug resistant enterococci were common from all three sources and frequently carried antibiotic resistance genes. This study showed that house flies and German cockroaches in the confined swine production environment likely serve as vectors and/or reservoirs of antibiotic resistant and potentially virulent enterococci and consequently may play an important role in animal and public health. We conducted DNA sequence analysis, morphological studies and pathology of a new cockroach Densovirus isolated from a swine farm. Blattella germanica densovirus (BgDNV) possesses three mRNAs for NS proteins, two of which are splice variants of the unspliced transcript. We characterized the genome organization of this virus and used mass spectrometry analysis to charachterize the amino acid composition of virus proteins. (USDA-NRI funded, collaboration with Mukha). As part of a project to measure and document the effects and impacts on the environment and human health of using total release foggers (TRFs) and to compare these with the effects and impacts of using reduced-risk gel baits within an IPM program, we have initiated studies of pyrethroid resistance in cockroaches. We found extensive and high levels of resistance in Raleigh populations of cockroaches. Rick Santangelo (Research specialist) is conducting this project (EPA-PESP and HUD funded). We have extended the population genetic studies to bed bug populations. We have (a) perfected a rearing system based on feeding on rabbit blood with artificial membranes; (b) identified and characterized 25 polymorphic microsatellite loci and intend to recover more through 454 sequencing; (c) collected populations of bed bugs in NC, throughout the US, and globally with assistance from several major pest control companies (mainly Orkin, Cooper Pest Solutions, and JC Ehrlich); (d) extracted DNA and characterized the structure and genetic differentiation of these populations; (e) conducted DNA sequence analysis for SNPs associated with kdr-based resistance to pyrethroids; (f) conducted extensive analysis of insecticide resistance using residual and topical applications. Warren Booth, a post doctoral researcher, Virna Saenz (PhD student) and Rick Santangelo (Research specialist) are conducting this project. (USA-NRI and Pest Management Foundation funded, collaboration with Vargo). We conducted studies of the potential for disease transmission by bed bugs. We screened field-collected populations of bed bugs for presence of Bartonella DNA. Virna Saenz (PhD student) and Rick Santangelo (Research specialist) are conducting this project. (collaboration with Vargo, Breitschwerdt). Isolated and in the process of characterizing behaviorally active compounds from bacterial species that mediate oviposition in mosquitoes. We identified several semiochemicals that attract mosquitoes to plant infusions, and other chemicals that stimulate gravid females to lay their eggs in water. These compounds have great potential as components of monitoring traps and in lethal ovitraps that target gravid (and potentially virus-infected) mosquitoes. Loganathan Ponnusamy and Katalin Böröczky, two post doctoral researchers, are conducting this project (Bill & Melinda Gates Foundation subcontract from Tulane University, collaboration with Apperson, Wesson). Continued investigations of the evolution of sexual communication in Heliothis moths. Most important findings: We conducted a comparative population genetic analysis to assess whether and how generalist and specialist life styles are reflected in differences in population structures. Population homogeneity of H. virescens likely results from the high mobility and its generalist feeding behaviour. H. subflexa, a specialist, exhibited substantially more population structure, with at least two subpopulations and thus some degree of metapopulation structure. We suggested that the patchy distribution of Physalis - the exclusive food source of H. subflexa - contributes to differences in population structure between these closely related species. (collaboration with Groot and Gould). We are making good progress on a project on the pre-mating reproductive isolating signals of moth species with emphasis on male close-range signaling. Jeremy Heath and Michiel Van Wijk are post-doctoral researchers on this project (NSF-funded in collaboration with Groot). Continuing studies on cuticular hydrocarbons and contact sex pheromone of the German cockroach and the involvement of contact pheromones in chemical sexual mimicry. This system has become, arguably, the best known contact pheromone system from the integrated perspective of chemical complexity, biosynthetic pathways, hormonal control, and roles in behavior. Examining the role of various sensory modalities in social facilitation of reproduction in the German cockroach. Thus far we have found that vision and chemicals likely are not involved, but mechanoreception appears to be important. Adrienn Uzsák (PhD student) conducted this project (collaboration with Bozkurt - Engineering). We delineated the behavioral resistance mechanism of sugar-aversion in the German cockroach in several populations of cockroaches. We have conducted extensive behavioral and electrophysiological assays to show that alterations in the peripheral gustatory system are responsible for this behavior. We have initiated molecular genetic studies. Ayako Wada-Katsumata (postdoctoral researcher) is conducting this project. (collaboration with Silverman).

Publications

  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Wada-Katsumata A., J. Silverman and C. Schal. 2013. Changes in taste neurons support the emergence of an adaptive behavior in cockroaches. Science 340: 972975.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: B�r�czky K., A. Wada-Katsumata, D. Batchelor, M. Zhukovskaya and C. Schal. 2013. Insects groom their antennae to enhance olfactory acuity. Proceedings of the National Academy of Sciences, USA 110: 36153620.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Carr A. L., R. M. Roe, C. Arellano, D. E. Sonenshine, C. Schal and C. S. Apperson. 2013. Responses of Amblyomma americanum and Dermacentor variabilis (Acari: Ixodidae) to odorants that attract haematophagous insects. Medical and Veterinary Entomology 27: 8695.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Groot A.T., H. Staudacher, A. Barthel, O. Inglis, G. Sch�fl, R.G. Santangelo, S. Gebauer-Jung S, H. Vogel, J. Emerson, C. Schal C, D.G. Heckel and F. Gould. 2013. One quantitative trait locus for intra- and interspecific variation in a sex pheromone. Molecular Ecology 22: 10651080.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Saenz V. L., R. G. Maggi, E. B. Breitschwerdt, J. Kim, E. L. Vargo and C. Schal. 2013. Survey of Bartonella spp. in U.S. bed bugs detects Burkholderia multivorans but not Bartonella. PLoS ONE 8(9): e73661. doi:10.1371/journal.pone.0073661.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Uzs�k A. and C. Schal. 2013. Sensory cues involved in social facilitation of reproduction in Blattella germanica females. PLoS ONE 8(2): e55678. doi:10.1371/journal.pone.0055678.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Uzs�k A. and C. Schal. 2013. Social interaction facilitates reproduction in male German cockroaches, Blattella germanica. Animal Behaviour 85: 15011509.


Progress 10/01/10 to 09/30/11

Outputs
OUTPUTS: As part of objective 1 of our proposed work, we have used bioassay-guided isolation and structure elucidation of several insect pheromones and other semiochemicals. The broad wood cockroach, Parcoblatta lata, is among the largest and most abundant of the wood cockroaches, constituting >50% of the biomass of the Cockaded woodpecker diet. Female P. lata emit a volatile, long distance sex pheromone, which, once identified and synthesized, could be deployed for monitoring cockroach populations. We identified and synthesized the pheromone as (4Z,11Z)-oxacyclotrideca-4,11-dien-2-one [= (3Z,10Z)-dodecadienolide; parcoblattalactone]. Parcoblattalactone is biologically active in electrophysiological assays and attracts not only P. lata but also several other Parcoblatta species in pine forests, underscoring its utility in monitoring several endemic wood cockroach species in red-cockaded woodpecker habitats.We also investigated environmental factors stimulating hatch of Aedes aegypti eggs. Our results show that bacteria or water-soluble compounds secreted by bacteria stimulate hatching of Ae. aegypti eggs. These research findings contribute new insight into an important aspect of the oviposition biology of Ae. aegypti, a virus vector of global importance, providing the basis for a new paradigm of environmental factors involved in egg hatching. We also investigated why some populations of B. germanica are behaviorally deterred from eating glucose. We found that the paraglossae alone were sufficient for maximum sensitivity to both phagostimulants and deterrents, including glucose as a deterrent in a glucose-averse strain. We are currently investigating how the chemosensory system can mediate opposite feeding responses to glucose in wild-type and glucose-averse strains. We are developing a newly discovered densovirus as a species-specific biological control agent to mitigate the medical and veterinary impacts of the German cockroach. We have investigated the expression and splicing patterns of the densovirus to understand its life cycle. The results of these studies have been presented at several international and national meetings, and invited seminars to Entomology Departments. PARTICIPANTS: Coby Schal (PI, Professor, NCSU) Satoshi Nojima (Senior Researcher, NCSU) Loganathan Ponnusamy (Senior Research Scholar, NCSU) Ayako Katsumata (postdoc, NCSU) Katalin Boroczky (postdoc, NCSU) Warren Booth (postdoc, NCSU) Jan Buellesbach (postdoc, NCSU) Dmitry Mukha (Collaborator, Vavilov Institute, Russia) Jules Silverman (Collaborator, NCSU) Rick Santangelo (technician, NCSU) Angela Bucci, Ann Carr, Dorit Eliyahu, Yvonne Matos, Angela Sierras, Adrrien Uzsak (graduate students, NCSU). This project provided professional development opportunities for undergraduates to engage in scientific research projects. TARGET AUDIENCES: Academic scientists, pest control operators, municipalities, livestock production managers, allergy clinicians PROJECT MODIFICATIONS: A no-cost-extension was approved.

Impacts
Cockroaches are recognized as a major cause of asthma morbidity in the urban, inner-city environment. Our recent research has moved beyond clinical, patient-based investigations to a more entomological perspective that addresses the production, physiological regulation, and developmental expression of cockroach allergens, thus providing insight into their functional biology and their relationship to current cockroach control strategies. Although successful removal of cockroach allergens from the infested environment has been difficult to accomplish with remedial sanitation, large-scale reductions in cockroach allergens below clinically relevant thresholds have recently been realized through suppression of cockroach populations. We have critically evaluated allergen mitigation studies from an entomological perspective, highlighting disparities between successful and failed attempts to lessen the cockroach allergen burden in homes. We showed that significant reductions in cockroach allergen concentrations in urban homes by reducing cockroach infestations. The findings from these studies could be used in developing new pest management approaches.

Publications

  • Saenz VL, W Booth, C Schal and EL Vargo. 2012. Genetic analysis of bed bug populations reveals small propagule size within individual infestations but high genetic diversity across infestations from the Eastern United States. Journal of Medical Entomology 49: 865-875.
  • Uzsak A and C Schal. 2012. Differential physiological responses of the German cockroach to social interactions during the ovarian cycle. Journal of Experimental Biology 215: 3037-3044.
  • Benda ND, C Brownie, C Schal and F Gould. 2011. Field observations of oviposition by a specialist herbivore on plant parts and plant species unsuitable as larval food. Environmental Entomology 40: 1478-1486.
  • Blomquist GJ, R Jurenka, C Schal and C Tittiger. 2011. Pheromone production: Biochemistry and molecular biology. In: Insect Endocrinology (L I Gilbert, ed), Chapter 12, pp. 523-567, Academic Press. Elsevier.
  • Booth W, L Million, RG Reynolds, GM Burghardt, EL Vargo, C Schal, AC Tzika, and GW Schuett. 2011. Consecutive virgin births in the new world boid snake, the Colombian rainbow boa, Epicrates maurus. Journal of Heredity 102: 759-763.
  • Eliyahu D, S Nojima, R G Santangelo, S Carpenter, F X Webster, D J Kiemle, C Gemeno, W S Leal and C Schal. 2012. An unusual macrocyclic lactone sex pheromone of Parcoblatta lata, a primary food source of the endangered red-cockaded woodpecker. Proceedings of the National Academy of Sciences doi: 10.1073/pnas.1111748109.
  • Groot AT, A Classen, O Inglis, CA Blanco, J Lopez, A Teran Vargas, C Schal, DG Heckel and G Schofl. 2011. Genetic differentiation across North America in the generalist moth Heliothis virescens and the specialist H. subflexa. Molecular Ecology 20: 2676-2692.
  • Kapelinskaya T, E Martynova, C Schal and D Mukha. 2011. Expression strategy of densonucleosis virus from the German cockroach, Blattella germanica. Journal of Virology 85: 11855-11870.
  • Ponnusamy L, K Boroczky, DM Wesson, C Schal and CS Apperson. 2011. Bacteria stimulate hatching of yellow fever mosquito eggs. PLoS ONE 6(9): e24409. doi:10.1371/journal.pone.0024409.
  • Richard F-J, C Schal, DR Tarpy and CM Grozinger. 2011. Effects of instrumental insemination and insemination quantity on Dufours gland chemical profiles and vitellogenin expression in honey bee queens (Apis mellifera). Journal of Chemical Ecology 37:1027-1036.
  • Booth W, VL Saenz, RG Santangelo, C Wang, C Schal and EL Vargo. 2012. Molecular markers reveal infestation dynamics of the bed bug (Hemiptera: Cimicidae) within apartment buildings. Journal of Medical Entomology 49: 535-546.
  • Carr AL, RM Roe, C Arellano, DE Sonenshine, C Schal and CS Apperson. 2012. Responses of Amblyomma americanum and Dermacentor variabilis (Acari: Ixodidae) to odorants that attract haematophagous insects. Medical and Veterinary Entomology (in press).


Progress 10/01/09 to 09/30/10

Outputs
OUTPUTS: As part of objective 1 of our proposed work, we have used bioassay-guided isolation and structure elucidation of several insect pheromones and other semiochemicals. We found that cockroach nymphs of various ages elicit courtship response in adult males. We extracted lipids from the cuticular surface of nymphs and, guided by behavioral assays, fractionated the extracts using various chromatography procedures. Mass spectrometry analysis revealed two classes of courtship-eliciting compounds: All nymphs possessed a novel, still unidentified compound that elicited courtship in adult males. In addition, in last instar females we isolated four of the six adult female-specific contact sex pheromone components. Our results support the interpretation that nymphs engage in sexual mimicry to gain access to male-produced nuptial tergal secretions which are exposed and can be secured only during courtship. Objective 2 concentrated on the biology of major cockroach allergens. We conducted a study to compare the effectiveness of IPM and conventional pest control in controlling German cockroach infestations, and concentrations of cockroach allergen in public school buildings. Both cockroach counts and allergen concentrations were dependent on the pest control approach, with highly significant differences between IPM-treated schools and conventionally-treated schools in both the cockroach trap counts and in the amount of allergen in dust samples. Cockroaches and allergen were primarily associated with food preparation and food service areas, and much less with classrooms and offices. Our data extend recent findings from studies in homes, showing that cockroach allergens can be reduced by cockroach elimination alone or by integrating several tactics including education, cleaning and pest control. In objective 3 we are developing a newly discovered densovirus as a species-specific biological control agent to mitigate the medical and veterinary impacts of the German cockroach. We have investigated the transcription patterns of the densovirus to understand its life cycle. When BGE2 cockroach cell culture was infected with the BgDNV virus, several viral RNAs, formed as a result of alternative splicing and use of alternative transcription termination codons, were transcribed from each DNA strand of the viral genome. We showed that splicing of RNAs encoding both VP and NS proteins occurred during infection and that the viral RNAs for NS proteins undergo alternative splicing. We determined the size of the transcripts synthesized from two viral promoters and showed that the transcription from the NS promoter starts much earlier than the transcription from the VP promoter. We also showed that the transcripts synthesized from antiparallel DNA strands of the BgDNV virus genome considerably overlap as a result of RNA processing. The data from these studies have been presented at several international and national meetings, and invited seminars to Entomology Departments. PARTICIPANTS: Coby Schal (PI, Professor, NCSU) Satoshi Nojima (Senior Researcher, NCSU) Alonso Suazo (postdoc, NCSU) Ayako Katsumata (postdoc, NCSU) Katalin Boroczky (postdoc, NCSU) Dmitry Mukha (Collaborator, Vavilov Institute, Russia) Godfrey Nalyanya (Extension Specialist, NCSU) Jules Silverman (Collaborator, NCSU) Rick Santangelo (technician, NCSU) Dorit Eliyahu, Elsa Youngsteadt (graduate students, NCSU). This project provided professional development opportunities for undergraduates to engage in scientific research projects. TARGET AUDIENCES: Academic scientists, pest control operators, municipalities, livestock production managers, allergy clinicians PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Cockroaches are recognized as a major cause of asthma morbidity in the urban, inner-city environment. Our recent research has moved beyond clinical, patient-based investigations to a more entomological perspective that addresses the production, physiological regulation, and developmental expression of cockroach allergens, thus providing insight into their functional biology and their relationship to current cockroach control strategies. Although successful removal of cockroach allergens from the infested environment has been difficult to accomplish with remedial sanitation, large-scale reductions in cockroach allergens below clinically relevant thresholds have recently been realized through suppression of cockroach populations. We have critically evaluated allergen mitigation studies from an entomological perspective, highlighting disparities between successful and failed attempts to lessen the cockroach allergen burden in homes. We showed that significant reductions in cockroach allergen concentrations in urban homes by reducing cockroach infestations. The findings from these studies could be used in developing new pest management approaches.

Publications

  • Ahmad A., A. Ghosh, C. Schal and L. Zurek. 2011. Insects in confined swine operations carry a large antibiotic resistant and potentially virulent enterococcal community. BMC Microbiology 11: 23.
  • Blomquist G. J., R. Jurenka, C. Schal and C. Tittiger. 2011. Biochemistry and molecular biology of pheromone production. In: Insect Endocrinology (L. I. Gilbert, ed.), Academic Press (in press).
  • Booth W., R. G. Santangelo, E. L. Vargo, D. V. Mukha and C. Schal. 2011. Population genetic structure in German cockroaches (Blattella germanica): Differentiated islands in an agricultural landscape. Journal of Heredity 102: 175-183.
  • Gemeno C., G. M. Williams and C. Schal. 2011. Effect of shelter on reproduction, growth and longevity of the German cockroach, Blattella germanica (Dictyoptera: Blattellidae). European Journal of Entomology 108: 205-210.
  • Mukha D. V., V. Mysina, V. Mavropulo and C. Schal. 2011. Structure and molecular evolution of the ribosomal DNA external transcribed spacer in the cockroach genus Blattella. Genome 54: 222-234.
  • Nojima S., D. J. Kiemle, F. X. Webster, C. S. Apperson and C. Schal. 2011. Nanogram-scale preparation and NMR analysis for mass-limited small volatile compounds. PLoS ONE (in press).
  • Groot A. T., A. Claβen, H. Staudacher, C. Schal and D. G. Heckel. 2010. Phenotypic plasticity in sexual communication signal of a noctuid moth. Journal of Evolutionary Biology 23: 2731-2738.
  • Kurczewski F. E., R. E. Coville and C. Schal. 2010. Observations on the nesting and prey of the solitary wasp, Tachysphex inconspicuus, with a review of nesting behavior in the T. obscuripennis species group. Journal of Insect Science 10:183.
  • Mankin R. W., R. D. Hodges, H. T. Nagle, C. Schal, R. M. Pereira and P. G. Koehler. 2010. Acoustic indicators for targeted detection of stored product and urban insect pests by inexpensive infrared, acoustic, and vibrational detection of movement. Journal of Economic Entomology 103: 1636-1646.
  • Menke S. B., W. Booth, R. R. Dunn, C. Schal, E. L. Vargo and J. Silverman. 2010. Is it easy to be urban Convergent success in urban habitats among lineages of a widespread native ant. PLoS ONE 5(2): e9194. doi:10.1371/journal.pone.0009194.
  • Ponnusamy L., D. M. Wesson, C. Arellano, C. Schal and C. S. Apperson. 2010. Species composition of bacterial communities influences attraction of mosquitoes to experimental plant infusions. Microbial Ecology 59: 158-173.
  • Ponnusamy L., N. Xu, D. M. Wesson, K. Boroczky, L. Abu Ayyash, C. Schal and C. S. Apperson. 2010. Oviposition responses of the mosquitoes Aedes aegypti and Aedes albopictus to experimental plant infusions in laboratory bioassays. Journal of Chemical Ecology 36: 709-719.
  • Schal C. 2011. Cockroaches. In: The Mallis Handbook of Pest Control (S. Hedges and D. Moreland, eds.), GIE Media (in press).
  • Wada-Katsumata A., J. Silverman and C. Schal. 2011. Differential inputs from chemosensory appendages mediate feeding responses to glucose in wild-type and glucose-averse German cockroaches, Blattella germanica. Chemical Senses (in press).
  • Wang G., G. M. Vasquez, C. Schal, L. J. Zwiebel and F. Gould. 2011. Functional characterization of pheromone receptors in the tobacco budworm Heliothis virescens. Insect Molecular Biology 20: 125-133.
  • Booth W., D. H. Johnson, S. Moore, C. Schal and E. L. Vargo. 2010. Evidence for viable, non-clonal but fatherless Boa constrictors. Biology Letters (in press, on line Nov. 4, doi: 10.1098/rsbl.2010.0793).
  • Crissman J. R., W. Booth, R. G. Santangelo, D. V. Mukha, E. L. Vargo and C. Schal. 2010. Population genetic structure of the German cockroach (Blattodea: Blattellidae) in apartment buildings. Journal of Medical Entomology 47: 553-564.
  • Tomalski M., W. Leimkuehler, C. Schal and E. L. Vargo. 2010. Metabolism of imidacloprid in workers of Reticulitermes flavipes (Isoptera: Rhinotermitidae). Annals of the Entomological Society of America 103: 84-95.
  • Gould F., M. Estock, N. K. Hillier, B. Powell, A. T. Groot, C. M. Ward, J. L. Emerson, C. Schal, N. J. Vickers. 2010. Sexual isolation of male moths explained by a single pheromone response QTL containing four receptor genes. Proceedings of the National Academy of Sciences, USA 107: 8660-8665. ( of commentary by David Heckel).
  • Groot A. T. C. A. Blanco, A. Claβen, O. Inglis, R. G. Santangelo, J. Lopez, D. G. Heckel and C. Schal. 2010. Variation in sexual communication of the tobacco budworm Heliothis virescens. Southwestern Entomologist 35: 367-372.
  • Youngsteadt E., P. G. Bustios and C. Schal. 2010. Divergent chemical cues elicit seed collecting by ants in an obligate multi-species mutualism in lowland Amazonia. PLoS ONE 5(12): e15822. doi:10.1371/journal.pone.0015822.


Progress 10/01/08 to 09/30/09

Outputs
OUTPUTS: As part of objective 1 of our proposed work, we have used bioassay-guided isolation and structure elucidation of several insect pheromones and other semiochemicals. We found that cockroach nymphs of various ages elicit courtship response in adult males. We extracted lipids from the cuticular surface of nymphs and, guided by behavioral assays, fractionated the extracts using various chromatography procedures. Mass spectrometry analysis revealed two classes of courtship-eliciting compounds: All nymphs possessed a novel, still unidentified compound that elicited courtship in adult males. In addition, in last instar females we isolated four of the six adult female-specific contact sex pheromone components. Our results support the interpretation that nymphs engage in sexual mimicry to gain access to male-produced nuptial tergal secretions which are exposed and can be secured only during courtship. Objective 2 concentrated on the biology of major cockroach allergens. We conducted a study to compare the effectiveness of IPM and conventional pest control in controlling German cockroach infestations, and concentrations of cockroach allergen in public school buildings. Both cockroach counts and allergen concentrations were dependent on the pest control approach, with highly significant differences between IPM-treated schools and conventionally-treated schools in both the cockroach trap counts and in the amount of allergen in dust samples. Cockroaches and allergen were primarily associated with food preparation and food service areas, and much less with classrooms and offices. Our data extend recent findings from studies in homes, showing that cockroach allergens can be reduced by cockroach elimination alone or by integrating several tactics including education, cleaning and pest control. In objective 3 we are developing a newly discovered densovirus as a species-specific biological control agent to mitigate the medical and veterinary impacts of the German cockroach. We have investigated the transcription patterns of the densovirus to understand its life cycle. When BGE2 cockroach cell culture was infected with the BgDNV virus, several viral RNAs, formed as a result of alternative splicing and use of alternative transcription termination codons, were transcribed from each DNA strand of the viral genome. We showed that splicing of RNAs encoding both VP and NS proteins occurred during infection and that the viral RNAs for NS proteins undergo alternative splicing. We determined the size of the transcripts synthesized from two viral promoters and showed that the transcription from the NS promoter starts much earlier than the transcription from the VP promoter. We also showed that the transcripts synthesized from antiparallel DNA strands of the BgDNV virus genome considerably overlap as a result of RNA processing. The data from these studies have been presented at several international and national meetings, and invited seminars to Entomology Departments. PARTICIPANTS: Coby Schal (PI, Professor, NCSU) Satoshi Nojima (Senior Researcher, NCSU) Alonso Suazo (postdoc, NCSU) Dmitry Mukha (Collaborator, Vavilov Institute, Russia) Godfrey Nalyanya (Extension Specialist, NCSU) Jules Silverman (Collaborator, NCSU) Rick Santangelo (technician, NCSU) Dorit Eliyahu, Elsa Youngsteadt (graduate students, NCSU). This project provided professional development opportunities for undergraduates to engage in scientific research projects. TARGET AUDIENCES: Academic scientists, pest control operators, municipalities, livestock production managers, allergy clinicians PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Cockroaches are recognized as a major cause of asthma morbidity in the urban, inner-city environment. Our recent research has moved beyond clinical, patient-based investigations to a more entomological perspective that addresses the production, physiological regulation, and developmental expression of cockroach allergens, thus providing insight into their functional biology and their relationship to current cockroach control strategies. Although successful removal of cockroach allergens from the infested environment has been difficult to accomplish with remedial sanitation, large-scale reductions in cockroach allergens below clinically relevant thresholds have recently been realized through suppression of cockroach populations. We have critically evaluated allergen mitigation studies from an entomological perspective, highlighting disparities between successful and failed attempts to lessen the cockroach allergen burden in homes. We showed that significant reductions in cockroach allergen concentrations in urban homes by reducing cockroach infestations. The findings from these studies could be used in developing new pest management approaches.

Publications

  • Booth W., E. Youngsteadt, C. Schal and E. L. Vargo. 2009. Polymorphic microsatellite loci for the ant-garden ant, Crematogaster levior (Forel). Conservation Genetics 10: 639-641.
  • Booth W., E. Youngsteadt, C. Schal and E. L. Vargo. 2009. Characterization of 8 polymorphic microsatellite loci in the Neotropical ant-garden ant, Camponotus femoratus (Fabricius). Conservation Genetics 10: 1401-1403.
  • Eliyahu D., S. Nojima, K. Mori and C. Schal. 2009. Jail baits: How and why nymphs mimic adult females of the German cockroach, Blattella germanica. Animal Behaviour 78: 1097-1105.
  • Groot A. T., O. Inglis, S. Bowdridge, R. G. Santangelo, C. Blanco, J. D. Lopez, A. T. Vargas, F. Gould and C. Schal. 2009. Geographic and temporal variation in moth chemical communication. Evolution 63: 1987-2003.
  • Groot A. T., M. Estock, J. Horowitz, J. Hamilton, R. G. Santangelo, C. Schal and F. Gould. 2009. QTL analysis of sex pheromone blend differences between two closely related moths: Insights into divergence in biosynthetic pathways. Insect Biochemistry and Molecular Biology 39: 568-577.
  • Nalyanya G., J. C. Gore, H. M. Linker and C. Schal. 2009. German cockroach allergen levels in North Carolina schools: Comparison of integrated pest management and conventional cockroach control. Journal of Medical Entomology 46: 420-427.
  • Suazo A., C. Gore and C. Schal. 2009. RNA interference-mediated knock-down of Bla g 1 in the German cockroach, Blattella germanica L., implicates this allergen-encoding gene in digestion and nutrient absorption. Insect Molecular Biology 18: 727-736.
  • Vasquez G. M., C. Schal and J. Silverman. 2009. Colony fusion in Argentine ants is guided by worker and queen cuticular hydrocarbon profile similarity. Journal of Chemical Ecology 35: 922-932.
  • Youngsteadt E., J. A. Baca, J. Osborne and C. Schal. 2009. Species-specific seed dispersal in an obligate ant-plant mutualism. PLoS One 4(2): e4335. doi:10.1371/journal.pone.0004335.


Progress 10/01/07 to 09/30/08

Outputs
OUTPUTS: As part of objective 1 of our proposed work, we have used bioassay-guided isolation and structure elucidation of several insect pheromones and other semiochemicals. We hypothesized two new candidate pheromone components and using bioassay-guided fractionation and chemical analyses of cuticular extracts of virgin females and synthesis of the (3S,11S)-isomer of each of the two predicted pheromone components, we showed that the epicuticle of the German cockroach contains these two compounds. The contact sex pheromone of the female German cockroach thus consists of at least six biosynthetically related components. We also found that contact with the antennae of several cockroach species elicited courtship behavior in German cockroach males. The heterospecific courtship-eliciting compounds were isolated and compared to the native sex pheromone components. We identified two active compounds from the cuticular extract of the Oriental cockroach, 11-methylheptacosan-2-one and 27-oxo-11-methylheptacosan-2-one. We also developed a simple, convenient, and highly efficient preparative GC system. The performance of this system with various types of capillary column traps and under various collection conditions was systematically investigated with model compounds. Objective 2 concentrated on the biology of major cockroach allergens. We set out to determine the effectiveness of pest control performed by professional entomologists, compared with commercial companies, in reducing cockroach allergen. We showed that reductions in allergen in cockroach-infested homes can be achieved by reducing infestations; however, the magnitude of allergen reduction is dependent on the thoroughness and effectiveness of cockroach eradication efforts. In objective 3 we are developing a newly discovered densovirus as a species-specific biological control agent to mitigate the medical and veterinary impacts of the German cockroach. We have investigated the consistent transcription patterns of the densovirus to understand its life cycle and also for understanding the fundamentals of regulation of eukaryotic gene expression. We found that several viral RNAs, formed as a result of alternative splicing and use of alternative transcription termination codons, are transcribed from each DNA strand of the viral genome. We determined the size of the transcripts synthesized from two viral promoters and showed that the transcription from the NS promoter starts much earlier than the transcription from the VP promoter. The data from these studies have been presented at several international and national meetings, and invited seminars to Entomology Departments. PARTICIPANTS: Coby Schal (PI, Professor, NCSU), Satoshi Nojima (Senior Researcher, NCSU), Dmitry Mukha (Collaborator, Vavilov Institute, Russia), Jules Silverman (Collaborator, NCSU), Rick Santangelo (technician, NCSU), Dorit Eliyahu, Elsa Youngsteadt (graduate students, NCSU). This project provided professional development opportunities for undergraduates to engage in scientific research projects. TARGET AUDIENCES: Academic scientists, pest control operators, municipalities, livestock production managers, allergy clinicians PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Cockroaches are recognized as a major cause of asthma morbidity in the urban, inner-city environment. Our recent research has moved beyond clinical, patient-based investigations to a more entomological perspective that addresses the production, physiological regulation, and developmental expression of cockroach allergens, thus providing insight into their functional biology and their relationship to current cockroach control strategies. Although successful removal of cockroach allergens from the infested environment has been difficult to accomplish with remedial sanitation, large-scale reductions in cockroach allergens below clinically relevant thresholds have recently been realized through suppression of cockroach populations. We have critically evaluated allergen mitigation studies from an entomological perspective, highlighting disparities between successful and failed attempts to lessen the cockroach allergen burden in homes. We showed that significant reductions in cockroach allergen concentrations in urban homes by reducing cockroach infestations. The findings from these studies could be used in developing new pest management approaches.

Publications

  • Youngsteadt E., S. Nojima, C. Haberlein, S. Schulz and C. Schal. 2008. Seed odor mediates an obligate ant-plant mutualism in Amazonian rainforest. Proceedings of the National Academy of Sciences, USA 105: 4571-4575.
  • Gore J. C. and C. Schal. 2007. Cockroach allergen biology and mitigation in the indoor environment. Annual Reviews of Entomology 52: 439-463.
  • Sever M. L., S. J. Arbes , J. C. Jr. Gore, R. G. Santangelo, B. Vaughn, H. Mitchell, C. Schal and D. C. Zeldin. 2007. Cockroach allergen reduction by cockroach control alone in low-income, urban homes: A randomized control trial. Journal of Allergy and Clinical Immunology 120: 849-855.
  • Eliyahu D., S. Nojima, S. M. Siefert, D. L. Comins and C. Schal. 2008. Identification of cuticular lipids eliciting interspecific courtship in the German cockroach, Blattella germanica. Naturwissenschaften 95: 403-412.
  • Eliyahu D., S. Nojima, K. Mori and C. Schal. 2008. New contact sex pheromone components of the German cockroach, Blattella germanica, predicted from the proposed biosynthetic pathway. Journal of Chemical Ecology 34: 229-237.
  • Fan Y., D. Eliyahu and C. Schal. 2008. Cuticular hydrocarbons as maternal provisions in embryos and nymphs of the cockroach Blattella germanica. Journal of Experimental Biology 211: 548-554.
  • Nojima S., C. S. Apperson and C. Schal. 2008. A simple, convenient, and efficient preparative GC system that uses a short megabore capillary column as a trap. Journal of Chemical Ecology 34: 418-428.
  • Ponnusamy L., N. Xu, S. Nojima, D. M. Wesson, C. Schal and C. S. Apperson. 2008. Identification of bacteria and bacteria-associated chemical cues that mediate oviposition site preferences by Aedes aegypti. Proceedings of the National Academy of Sciences, USA 105: 9262-9267.
  • Ponnusamy L., N. Xu, G. Stav, D. M. Wesson, C. Schal and C. S. Apperson. 2008. Diversity of bacterial communities in container habitats of mosquitoes. Microbial Ecology 56: 593-603.
  • Vasquez G., C. Schal and J. Silverman. 2008. Cuticular hydrocarbons as queen adoption cues in the invasive Argentine ant. Journal of Experimental Biology 211: 1249-1256.


Progress 10/01/05 to 09/30/06

Outputs
Exposure and sensitization to cockroach allergens is an important risk factor for allergic disease in humans. Enzyme-linked immunosorbent assay was used to quantify the allergen contents of feces and various anatomical tissues of the German cockroach, and Northern blot analysis was used to elucidate tissue-specific expression of the Bla g 1 and Bla g 4 allergens. We conducted functional molecular genetic studies, including RNA interference and quantitative PCR, on the roles of cockroach allergenic proteins in cockroach physiology. We showed that Bla g 4 is specifically expressed in the male reproductive system and can be completely suppressed with RNA interference technology. We continue progress on developing an integrated cockroach management program in confined swine production, including testing the efficacy of various new technologies and formulations for cockroach control, and studying the environmental distribution of cockroach allergens in swine farms and approaches to reduce allergens. We also demonstrated that the German cockroach and house flies play important roles in the ecology of antibiotic resistant enterococci in confined swine production. We also showed in a randomized control trial that significant cockroach allergen reduction could be accomplished in low-income, urban homes by cockroach control alone.

Impacts
The German cockroach is a major urban pest world-wide that can acquire, carry, and transfer pathogens. This project is of basic value and of practical pest management significance. The cuticular wax layer is unique to arthropods. Because hydrocarbons play important functions, their trafficking is critical in microhabitat choice and foraging behavior. Cuticular hydrocarbons therefore are a prime target for the development of specific control technologies. Understanding how biological control agents affect populations of the German cockroach is critical for reducing reliance on neurotoxic broad-spectrum pesticides. Our research on densoviruses will develop new biological control agents to combat cockroaches. Finally, by developing new strategies to reduce cockroach populations, allergen levels are also reduced.

Publications

  • Booth W., S. M. Bogdanowicz, P. A. Prodohl, R. G. Harrison, C. Schal, and E. L. Vargo. 2006. Identification and characterization of ten polymorphic microsatellite loci in the German cockroach, Blattella germanica. Molecular Ecology Notes (online doi: 10.1111/j.1471-8286.2006.01663.x).
  • Gore J. C. and C. Schal. 2007. Cockroach allergen biology and mitigation in the indoor environment. Annual Reviews of Entomology 52: 439-463.
  • Groot A. T., J. Bennett, J. Hamilton, R. G. Santangelo, C. Schal, and F. Gould. 2006. Experimental evidence for interspecific directional selection force on moth pheromone communication. Proceedings of the National Academy of Sciences, USA 103: 5858-5863.
  • Kagramanova A. S, A. L. Korolev, C. Schal, D. V. Mukha. 2006. Length polymorphism of integrated copies of R1 and R2 retrotransposons in the German cockroach (Blattella germanica) as a potential marker for population and phylogenetic studies. Russian Journal of Genetics 42: 397-401.
  • Kovanci O. B., C. Schal, J. F. Walgenbach and G. G. Kennedy. 2006. Effects of pheromone loading, dispenser age, and trap height on pheromone trap catches of the oriental fruit moth in apple orchards. Phytoparasitica 34: 252-260.
  • Mukha D. V., A. G. Chumachenko, M. J. Dykstra, J. Kurtti and C. Schal. 2006. Characterization of a new densovirus infecting the German cockroach, Blattella germanica. Journal of General Virology 87: 1567-1575.
  • Sheck A. l., A. Groot, C. M. Ward, C. Gemeno, J. Wang, C. Schal, and F. Gould. 2006. Genetics of sex pheromone blend differences between Heliothis virescens and Heliothis subflexa: A chromosome mapping approach. Journal of Evolutionary Biology 19: 600-617.
  • Groot A. T., R. G. Santangelo, E. Ricci, C. Brownie, F. Gould and C. Schal. 2007. Differential attraction of Heliothis subflexa males to synthetic pheromone lures in Eastern US and Western Mexico. Journal of Chemical Ecology 33: 353-368.
  • Mukha D. V., A. S. Kagramanova, I. V. Lazebnaya, O. E. Lazebnyi, E. L. Vargo and C. Schal. 2007. Intraspecific variation and population structure of the German cockroach, Blattella germanica, revealed with RFLP analysis of the nontranscribed spacer region of ribosomal DNA. Medical and Veterinary Entomology 21: 1-9.


Progress 10/01/04 to 09/30/05

Outputs
Exposure and sensitization to cockroach allergens is an important risk factor for allergic disease in humans. Enzyme-linked immunosorbent assay was used to quantify the allergen contents of feces and various anatomical tissues of the German cockroach, and Northern blot analysis was used to elucidate tissue-specific expression of the Bla g 1 and Bla g 4 allergens. The Bla g 1 gene is exclusively expressed by midgut cells and is up-regulated in response to feeding. Bla g 4 localized only in the accessory reproductive system of the male and is regulated by juvenile hormone. We continue work on allergen mitigation in infested homes, and show that thorough cockroach control alone can significantly lower allergen concentrations. The sex pheromone for the German cockroach, Blattella germanica, has been characterized as gentisyl quinone isovalerate. The sex-pheromone producing gland in adult females was identified in 1993, but thermal instability of the pheromone made characterization difficult. Finally, using a new preparative gas chromatography approach coupled with electroantennographic detection, we have isolated and characterized the pheromone, which we termed blattellaquinone, and confirmed the identification by chemical synthesis. The synthetic pheromone was active in behavioral assays and highly effective in field trapping tests, which suggest that it may provide a new tool in cockroach population detection, monitoring and control.

Impacts
The German cockroach is a major urban pest world-wide that can acquire, carry, and transfer pathogens. This project is of basic value and of practical pest management significance. The cuticular wax layer is unique to arthropods. Because hydrocarbons play important functions, their trafficking is critical in microhabitat choice and foraging behavior. Cuticular hydrocarbons therefore are a prime target for the development of specific control technologies. Understanding how biological control agents affect populations of the German cockroach is critical for reducing reliance on neurotoxic broad-spectrum pesticides. Our research on densoviruses will develop new biological control agents to combat cockroaches. Finally, by developing new strategies to reduce cockroach populations, allergen levels are also reduced.

Publications

  • CHUMACHENKO A. G., C. SCHAL AND D. V. MUKHA. 2005. Discovery of retrotransposons of the cockroach Blattella germanica. Doklady Biochemistry and Biophysics: A Journal of the Russian Academy of Sciences 401: 104-107.
  • FAN Y., J. C. GORE, K. O. REDDING, L. D. VAILES, M. D. CHAPMAN AND C. SCHAL. 2005. Tissue localization and regulation by juvenile hormone of human allergen Bla g 4 from German cockroach, Blattella germanica (L.). Insect Molecular Biology 14: 45-53.
  • GORE J. C. AND C. SCHAL. 2005. Expression, production and excretion of Bla g 1, a major human allergen, in relation to food intake in the German cockroach, Blattella germanica (L.). Medical and Veterinary Entomology 19: 127-134.
  • LAZEBNAYA I. V., S. K. SEMENOVA, O. E. LAZEBNYI, C. SCHAL AND D. V. MUKHA. 2005. Nuclear rDNA variability in laboratory strains of the German cockroach Blattella germanica L. (Blattellidae). Russian Journal of Genetics 41: 468-472.
  • NOJIMA S., C. SCHAL, F. X. WEBSTER, R. G. SANTANGELO AND W. L. ROELOFS. 2005. Identification of the sex pheromone of the German cockroach, Blattella germanica. Science 307: 1104-1106.
  • WILLIAMS, G. M., H. M. LINKER, M. G. WALDVOGEL, R. B. LEIDY, AND C. SCHAL. 2005. Comparison of conventional and integrated pest management programs in public schools. Journal of Economic Entomology 98: 1275-1283.
  • YOUNGSTEADT E., Y. FAN, B. STAY, AND C. SCHAL. 2005. Cuticular hydrocarbon synthesis and its maternal provisioning to embryos in the viviparous cockroach Diploptera punctata. Journal of Insect Physiology 51: 803-809.


Progress 10/01/03 to 09/30/04

Outputs
Exposure and sensitization to cockroach allergens is an important risk factor for allergic disease in humans. Enzyme-linked immunosorbent assay was used to quantify the allergen contents of feces and various anatomical tissues of the German cockroach, and Northern blot analysis was used to elucidate tissue-specific expression of the Bla g 1 allergen. The Bla g 1 protein is most prevalent in the midgut, and the Bla g 1 gene is exclusively expressed by midgut cells. Adult females produce and excrete in their feces significantly more Bla g 1 than males or nymphs. The combined intervention of occupant education, insecticide bait application, and professional cleaning significantly reduced cockroach numbers and allergen levels in inner-city homes. A continuation study showed that among intervention homes, allergen concentrations remained essentially unchanged for 12 months. However, in crossed-over control homes, now treated only with insecticide bait the allergen concentrations decreased significantly and at month 12, they did not significantly differ between intervention and crossed-over control homes. Thus, reductions in cockroach allergen concentrations achieved through the combined intervention of occupant education, insecticide application, and professional cleaning can be maintained with continued cockroach control. Surprisingly, and in contrast to previous reports, thorough insecticide bait application alone significantly lowered allergen concentrations. Vector competence of German cockroaches for one of the most important porcine bacterial pathogens, verotoxigenic Escherichia coli F18, was evaluated in laboratory bioassays using a culturing approach followed by multiplex PCR. Viable and virulent cells of E. coli F18 were detected in cockroach feces for up to 8 d after the initial exposure. The population of fecal coliforms in cockroach feces was high and comparable to that of piglet feces. This study demonstrates that cockroaches may serve as important mechanical vectors of pathogenic E. coli. Integrated management of cockroach populations should be incorporated into the disease prevention and control programs in the swine industry. Boric acid dust has been shown to be an effective alternative to conventional neurotoxic insecticides. Borate solutions were evaluated for effectiveness as baits against the German cockroach. Results showed that boric acid was more effective than sodium tetraborate or disodium octaborate tetrahydrate, and that aqueous solutions containing mixtures of 0.5-2% boric acid and any of several inexpensive sugars, including fructose, glucose, maltose and sucrose as a phagostimulant, at molar concentrations of 0.05-1.0-M, can provide rapid and effective kill of German cockroaches. This prototype bait formulation was also highly effective controlling cockroaches in swine farms.

Impacts
The German cockroach is a major urban pest world-wide that can acquire, carry, and transfer pathogens. This project is of basic value and of practical pest management significance. The cuticular wax layer is unique to arthropods. Because hydrocarbons play important functions, their trafficking is critical in microhabitat choice and foraging behavior. Cuticular hydrocarbons therefore are a prime target for the development of specific control technologies. Understanding how biological control agents affect populations of the German cockroach is critical for reducing reliance on neurotoxic broad-spectrum pesticides. Our research on dnsoviruses will develop new biological control agents to combat cockroaches. Finally, by developing new strategies to reduce cockroach populations, allergen levels are also reduced.

Publications

  • TREXLER J. D., C. S. APPERSON, L. ZUREK, C. GEMENO, C. SCHAL, M. KAUFMAN, E. WALKER, D. W. WATSON AND L. WALLACE. 2003. Role of bacteria in mediating the oviposition responses of Aedes albopictus (Diptera: Culicidae). Journal of Medical Entomology 40: 841-848.
  • ARBES S. J., JR., M. SEVER, J. MEHTA, J. C. GORE, C. SCHAL, B. VAUGHN, H. MITCHELL AND D. C. ZELDIN. 2004. Abatement of cockroach allergens (Bla g 1 and Bla g 2) in low-income, urban housing: Month 12 continuation results. Journal of Allergy and Clinical Immunology 113: 109-114.
  • ELIYAHU D., K. MORI, W. S. LEAL AND C. SCHAL. 2004. Behavioral activity of stereoisomers and a new component of the contact sex pheromone of female German cockroach, Blattella germanica. Journal of Chemical Ecology 30: 1839-1848.
  • GEMENO C., L. ZUREK AND C. SCHAL. 2004. Control of Herpomyces spp. (Ascomycetes: Laboulbeniales) infection in the wood cockroach, Parcoblatta lata (Dictyoptera: Blattodea: Blattellidae), with benomyl. Journal of Invertebrate Pathology 85: 132-135.
  • GORE J. C. AND C. SCHAL. 2004. Evaluation of boric acid-sugar solutions as baits for management of German cockroach infestations. Journal of Economic Entomology 97: 581-587.
  • GORE J. C. AND C. SCHAL. 2004. Gene expression and tissue distribution of the major human allergen Bla g 1 in the German cockroach, Blattella germanica L. (Dictyoptera: Blattellidae). Journal of Medical Entomology 41: 953-960.
  • GORE J. C., L. ZUREK, R. G. SANTANGELO, S. M. STRINGHAM, D. W. WATSON AND C. SCHAL. 2004. Water solutions of boric acid and sugar for management of German cockroach populations in livestock production systems. Journal of Economic Entomology 97: 715-720.
  • HOLBROOK, G. L. AND C. SCHAL. 2004. Maternal investment affects offspring phenotypic plasticity in a viviparous cockroach. Proceedings of the National Academy of Sciences, USA 101: 5595-5597.
  • ZUREK L. AND C. SCHAL. 2004. Evaluation of the German cockroach, Blattella germanica, as a vector of verotoxigenic Escherichia coli F18 in confined swine production. Veterinary Microbiology 101: 263-267.


Progress 10/01/02 to 09/30/03

Outputs
Hydrocarbons are synthesized by the abdominal integument. We developed a method for separation of oenocytes from other cells in the abdominal integument using enzymatic dissociation followed by Percoll gradient centrifugation. Radiolabeled propionate was then used to monitor de novo synthesis of hydrocarbons by dissociated cells. Oenocyte-enriched cell suspensions of abdominal sternites synthesized hydrocarbons, whereas suspensions enriched with epidermal cells did not. Our results show conclusively that hydrocarbons are produced by oenocytes. Furthermore, these data support a hemolymph pathway for transport and delivery of hydrocarbons and insecticides to both external and internal tissues, including the epicuticle, fat body, and ovaries. Females of the brownbanded cockroach, Supella longipalpa, release a sex pheromone (supellapyrone). We showed that males are attracted to the RR stereoisomer and to high concentrations of the SR isomer. Behaviorally, RR was the most active isomer, but males were also attracted to much higher dosages of SR and SS. But, in EAG assays, the antennae of males S. longipalpa showed high and similar sensitivity to RR and SR. Positive cross-adaptation between RR and SR suggests that these two compounds stimulate the same receptor cells. We also showed that peak height and width are independent parameters of the EAG, probably representing different intrasensillar events, and likely resulting in the expression of different behavioral responses. We conducted two studies to investigate strategies for implementation of cockroach control. Boric acid dust treatments were evaluated as a tool for the integrated management of the German cockroach in commercial confined swine production. The efficacy of boric acid dust was comparable to that of an organic residual insecticide, cyfluthrin, which is commonly used to control cockroaches in this environment. Fall treatments suppressed the cockroach population for longer durations than treatments in the Spring. Boric acid dust is an effective, inexpensive, and low risk (to animal and human health, and the environment) alternative for the management of cockroaches in livestock production systems. We also developed strategies to implement clinically relevant reductions in exposure to cockroach allergen, an important risk factor for asthma in inner-city households. Interventions consisted of occupant education, placement of insecticide bait, and professional cleaning. Among intervention homes, allergen concentrations decreased significantly. Future studies will test the effectiveness of interventions in asthma prevention trials.

Impacts
The German cockroach is a major urban pest world-wide that can acquire, carry, and transfer pathogens. This project is of basic value and of practical pest management significance. The cuticular wax layer is unique to arthropods. Because hydrocarbons play important functions, their trafficking is critical in microhabitat choice and foraging behavior. Cuticular hydrocarbons therefore are a prime target for the development of specific control technologies. Understanding how biological control agents affect populations of the German cockroach is critical for reducing reliance on neurotoxic broad-spectrum pesticides. Our research on dnsoviruses will develop new biological control agents to combat cockroaches. Finally, by developing new strategies to reduce cockroach populations, allergen levels are also reduced.

Publications

  • GEMENO C., W. S. LEAL, K. MORI AND C. SCHAL. 2003. Behavioral and electropysiological responses of the brownbanded cockroach, Supella longipalpa, to stereoisomers of its sex pheromone, supellapyrone. Journal of Chemical Ecology 29: 1769-1783.
  • GEMENO C., K. SNOOK, N. BENDA AND C. SCHAL. 2003. Behavioral and electrophysiological evidence for volatile sex pheromones in Parcoblatta wood cockroaches. Journal of Chemical Ecology 29: 37-54.
  • HOLBROOK, G. L., J. ROEBUCK, C. B. MOORE AND C. SCHAL. 2003. Origin and extent of resistance to fipronil in the German cockroach, Blattella germanica (L.) (Dictyoptera: Blattellidae). Journal of Economic Entomology 96: 1548-1558.
  • MUKHA D. V. AND C. SCHAL. 2003. A Densovirus of German Cockroach Blattella germanica: Detection, nucleotide sequence, and genome organization. Molecular Biology 37: 513-523.
  • SCHAL C., Y. FAN AND G. J. BLOMQUIST. 2003. Regulation of pheromone biosynthesis, transport, and emission in cockroaches. In: Insect Pheromones - Biochemistry and Molecular Biology (G. J. Blomquist and R. Vogt, Eds.), Ch. 10, pp. 283-322, Academic Press, New York.
  • TREXLER J. D., C. S. APPERSON, C. GEMENO, M. J. PERICH, D. CARLSON AND C. SCHAL. 2003. Field and laboratory evaluations of potential oviposition attractants for Aedes albopictus (Diptera: Culicidae). Journal of the American Mosquito Control Association 19: 228-234.
  • ZUREK L., J. C. GORE, M. S. STRINGHAM, D. W. WATSON, M. G. WALDVOGEL AND C. SCHAL. 2003. Boric acid dust as a component of an integrated cockroach management program in confined swine production. Journal of Economic Entomology 96: 1362-1366.
  • ARBES S. J., JR., M. SEVER, J. ARCHER, E. H. LONG, J. C. GORE, C. SCHAL, M. WALTER, B. NUEBLER, B. VAUGHN, H. MITCHELL, E. LIU, N. COLLETTE, P. ADLER AND D. C. ZELDIN. 2003. Abatement of cockroach allergen (Bla g 1) in low-income, urban housing - a randomized controlled trial. Journal of Allergy and Clinical Immunology 112: 339-345.
  • FAN Y., L. ZUREK, M. J. DYKSTRA, AND C. SCHAL. 2003. Hydrocarbon synthesis by enzymatically dissociated oenocytes of the abdominal integument of the German cockroach, Blattella germanica. Naturwissenschaften 90: 121-126.


Progress 10/01/01 to 09/30/02

Outputs
Lipophorin, a multi-functional lipid carrier in insect blood transports hormones, pheromones, cuticular waxes, and other lipids. We have documented involvement of lipophorin in hydrocarbon transport in the German cockroach, determined which tissues store hydrocarbons, and where hydrocarbons are unloaded. Large amounts of hydrocarbons accumulate during vitellogenesis in the developing basal oocytes, and all ovarian hydrocarbons are deposited into an egg case (ootheca) during oviposition. Hydrocarbons are not synthesized by the ovaries, but are delivered by hemolymph lipoproteins and accumulate within the basal oocytes. This is the first report that shows that copious amounts of maternal hydrocarbons are provisioned in oocytes, and the existence of a hydrocarbon transport pathway involving hemolymph lipoproteins. We also evaluated mortality of German cockroaches caused by Metarhizium anisopliae alone and in combination with different formulations of boric acid and demonstrated a synergistic interaction between these two insecticides. The effect of the entomopathogenic fungus Entomophthora muscae on house flies was also investigated. Infected males are highly attracted to dead female flies infected with the fungus. Our behavioral assays demonstrated that the attraction is sex-specific - males were attracted more to infected females than to infected males, regardless of cadaver size. Because Young E. muscae-infected female flies accumulated significantly less sex pheromone and other hydrocarbons on their cuticular surface than uninfected females, we conclude that chemical analyses showed that chemical cues other than (Z)-9-tricosene, visual cues other than abdomen size, or a combination of both sets of cues might be responsible for attraction of house fly males to E. muscae-infected females. The organization, structure, and nucleotide variability of the ribosomal repeat unit was compared among families, genera, and species of cockroaches (Insecta: Blattoidea). Sequence comparisons and molecular phylogenetic analyses were used to describe rDNA repeat unit variation at differing taxonomic levels. Comparative analysis of the nucleotide sequences of the rDNA internal transcribed spacers (ITS1 and ITS2) among closely related species of Blattella and Periplaneta reveals that ITS sequences can vary widely in primary sequence, length, and folding pattern. Secondary structure estimates for the ITS region of Blattella species indicate that variation in this spacer region can also influence the folding pattern of the 5.8S subunit. These results support the idea that ITS sequences play an important role in the stability and function of the rRNA cluster.

Impacts
The German cockroach is a major urban pest world-wide that can acquire, carry, and transfer pathogens. This project is of basic value and of practical pest management significance. The cuticular wax layer is unique to arthropods. Because hydrocarbons play important functions, their trafficking is critical in microhabitat choice and foraging behavior. Cuticular hydrocarbons therefore are a prime target for the development of specific control technologies. Understanding how biological control agents affect populations of the German cockroach is critical for reducing reliance on neurotoxic broad-spectrum pesticides.

Publications

  • FAN Y., J. CHASE, V. L. SEVALA and C. SCHAL. 2002. Lipophorin-facilitated hydrocarbon uptake by oocytes in the German cockroach, Blattella germanica (l.). Journal of Experimental Biology 205: 781-790.
  • MUKHA D. V., B. M. WIEGMANN and C. SCHAL. 2002. Evolution and phylogenetic information content of the ribosomal DNA repeat unit in the Blattodea (Insecta). Insect Biochemistry and Molecular Biology 32: 951-960.
  • ZUREK L., D. W. WATSON, S. B. KRASNOFF and C. SCHAL. 2002. Effect of the Entomopathogenic fungus, Entomophthora muscae (Zygomycetes: Entomophthoraceae), on sex pheromone and other cuticular hydrocarbons of the house fly, Musca domestica. Journal of Invertebrate Pathology 80: 171-176.
  • ZUREK L., D. W. WATSON, and C. SCHAL. 2002. Synergism between Metarhizium anisopliae (Deuteromycota: Hyphomycetes) and boric acid against the German cockroach (Dictyoptera: Blattellidae). Biological Control 23: 296-302.


Progress 10/01/00 to 09/30/01

Outputs
Lipophorin, a multi-functional lipid carrier in insect blood transports hormones, pheromones, cuticular waxes, and other lipids. We have documented involvement of lipophorin in hydrocarbon transport in the German cockroach, determined which tissues store hydrocarbons, and where hydrocarbons are unloaded. The pattern of hydrocarbon production is coordinated with feeding and with oocyte maturation in adults. In both adult females and nymphs, hydrocarbon synthesis is restricted to the abdominal integument. Nymphs retain newly formed hydrocarbons internally. Early in the last stadium the internal pool of hydrocarbons is largely associated with the hemolymph. Later, hydrocarbons accumulate in the fat body. Around mid-stadium the new cuticle begins to form and an increasing fraction of internal hydrocarbons associate with the pharate cuticle. The shuttling of hydrocarbons from sites of synthesis to fat body and then to the integument requires hemolymph transport. We isolated and characterized a high density lipophorin. Antibodies to lipophorin were generated and an ELISA was developed to titer lipophorin. We established that no hydrocarbon circulates unbound in the hemolymph, that all hemolymph hydrocarbon is bound to lipophorin, and that no other hemolymph proteins carry hydrocarbons. The capacity of lipophorin to accept newly synthesized hydrocarbons from integument was confirmed in vitro. The presence of lipophorin is mandatory for transfer of newly synthesized hydrocarbons to the hemolymph, a step that is necessary for hydrocarbon trafficking.. A study of transfer of insecticide baits among cockroaches revealed that baits can effectively be disseminated through an infestation, but by different mechanisms. Fast acting baits, like fipronil, were effective through regurgitation of ingested baits.

Impacts
This project is of basic value and of practical pest management significance. The cuticular wax layer is unique to arthropods. Because hydrocarbons play important functions, their trafficking is critical in microhabitat choice and foraging behavior. Cuticular hydrocarbons therefore are a prime target for the development of specific control technologies. The German cockroach is a major urban pest world-wide that can acquire, carry, and transfer pathogens.

Publications

  • BUCZKOWSKI G. and C. SCHAL. 2001. Method of insecticide delivery affects horizontal transfer of fipronil in the German cockroach (Dictyoptera: Blattellidae). Journal of Economic Entomology 94: 680-685.
  • BUCZKOWSKI G. and C. SCHAL. 2001. Emetophagy: Fipronil-induced regurgitation of bait and its dissemination from German cockroach adults to nymphs. Pesticide Biochemistry and Physiology 71: 147-155.
  • BUCZKOWSKI G., R. J. KOPANIC and C. SCHAL. 2001. Transfer of ingested insecticides among cockroaches: effects of active ingredient, bait formulation, and assay procedures. Journal of Economic Entomology 94: 1229-1236.
  • KOPANIC R. J. JR., G. L. HOLBROOK, V. SEVALA and C. SCHAL. 2001. An adaptive benefit of facultative coprophagy in the German cockroach Blattella germanica (L.). Ecological Entomology 26: 154-162.
  • MPURU S., G. J. BLOMQUIST, C. SCHAL, M. ROUX, M. KUENZLI, G. DUSTICIER, J. -L. CLEMENT and A. -G. BAGNERES. 2001. Effect of age and sex on the production of internal and external hydrocarbons and pheromones in the housefly, Musca domestica. Insect Biochemistry and Molecular Biology 31: 139-155.
  • SCHAL, C., V. SEVALA, M. DE L. CAPURRO, T. E. SNYDER, G. J. BLOMQUIST, and A.-G. BAGNERES. 2001. Tissue distribution and lipophorin transport of hydrocarbons and sex pheromones in the house fly, Musca domestica. Journal of Insect Science 1: 12 (11 p).


Progress 10/01/99 to 09/30/00

Outputs
Lipophorin, a multi-functional lipid carrier in insect blood transports hormones, pheromones, cuticular waxes, and other lipids. We have documented involvement of lipophorin in hydrocarbon transport in the German cockroach, determined which tissues store hydrocarbons, and where hydrocarbons are unloaded. The pattern of hydrocarbon production is coordinated with feeding and with oocyte maturation in adults. In both adult females and nymphs, hydrocarbon synthesis is restricted to the abdominal integument. Nymphs retain newly formed hydrocarbons internally. Early in the last stadium the internal pool of hydrocarbons is largely associated with the hemolymph. Later, hydrocarbons accumulate in the fat body. Around mid-stadium the new cuticle begins to form and an increasing fraction of internal hydrocarbons associate with the pharate cuticle. The shuttling of hydrocarbons from sites of synthesis to fat body and then to the integument requires hemolymph transport. We isolated and characterized a high density lipophorin. Antibodies to lipophorin were generated and an ELISA was developed to titer lipophorin. We established that no hydrocarbon circulates unbound in the hemolymph, that all hemolymph hydrocarbon is bound to lipophorin, and that no other hemolymph proteins carry hydrocarbons. The capacity of lipophorin to accept newly synthesized hydrocarbons from integument was confirmed in vitro. The presence of lipophorin is mandatory for transfer of newly synthesized hydrocarbons to the hemolymph, a step that is necessary for hydrocarbon trafficking. To study hydrocarbon transport by lipophorin to the oocytes, we determined hemolymph volume by inulin dilution, hydrocarbon titer by gas chromatography, lipophorin titer by ELISA, juvenile hormone titer by gas chromatography-mass spectrometry, and hydrocarbon content of the ovaries by gas chromatography. Results show that the ovary is a major deposition site for hydrocarbons, but only small amounts of lipophorin appear to enter the oocytes. We developed an in vitro system to study hydrocarbon uptake by oocytes, and showed that juvenile hormone stimulates hydrocarbon incorporation into oocytes. Adipokinetic hormone, a peptide released from the corpora cardiaca, stimulates conversion of stored triacylglycerol to diacylglycerol in insects that are capable of lipid-fueled flight. We examined the response of B. germanica to adipokinetic hormone and to hypertrehalosemic hormone. Neither stimulated either production of hydrocarbon or their uptake by lipophorin. A gas chromatography and fast Fourier transform study examined the biophysical properties of hydrocarbons. The melting temperature of oothecal hydrocarbons was highest > epicuticular hydrocarbons > hemolymph hydrocarbons. The cockroach ootheca is particularly well protected by an abundance of n-alkanes and its external hydrocarbons exhibit the highest melting temperature of any of the hydrocarbon blends. The female somehow delivers certain hydrocarbons to the egg case.

Impacts
This project is of basic value and of practical pest management significance. The cuticular wax layer is unique to arthropods. Because hydrocarbons play important functions, their trafficking is critical in microhabitat choice and foraging behavior. Cuticular hydrocarbons therefore are a prime target for the development of specific control technologies. The German cockroach is a major urban pest world-wide that can acquire, carry, and transfer pathogens.

Publications

  • NALYANYA G., C. B. MOORE and C. SCHAL. 2000. Integration of repellents, attractants, and insecticides in a Apush-pull@ strategy for managing German cockroach (Dictyoptera: Blattellidae) populations. Journal of Medical Entomology 37: 427-434.
  • SEVALA V., A. -G. BAGNERES, M. KUENZLI, G. J. BLOMQUIST and C. SCHAL. 2000. Cuticular hydrocarbons of the termite Zootermopsis Nevadensis (Hagen): Caste differences and role of lipophorin in transport of hydrocarbons and hydrocarbon metabolites. Journal of Chemical Ecology 26: 765-789.
  • YOUNG H. P., J. LARABEE, A. GIBBS and C. SCHAL. 2000. Relationship between tissue-specific hydrocarbon profiles and their melting temperatures in the cockroach Blattella germanica (L.). Journal of Chemical Ecology 26: 1245-1263.
  • HOLBROOK G. L., J. A. S. BACHMANN and C. SCHAL. 2000. Effects of ovariectomy and mating on the activity of the corpora allata in adult female Blattella germanica (L.) (Dictyoptera : Blattellidae). Physiological Entomology 25: 27-34.
  • MUKHA D. V., A. P. SIDORENKO, I. V. LAZEBNAYA, B. M. WIEGMANN and C. SCHAL. 2000. Analysis of intraspecies polymorphism in the ribosomal DNA cluster of the cockroach Blattella germanica. Insect Molecular Biology 9: 217-222.
  • HOLBROOK G. L., E ARMSTRONG, J. A. S. BACHMANN, B. M. DEASY and C. SCHAL. 2000. Role of feeding in the reproductive >group effect= in females of the German cockroach Blattella germanica (L.). Journal of Insect Physiology 46: 941-949.


Progress 10/01/98 to 09/30/99

Outputs
Lipophorin, a multi-functional lipid carrier in insect blood transports hormones, pheromones, cuticular waxes, and other lipids. We have documented involvement of lipophorin in hydrocarbon transport in the German cockroach, determined which tissues store hydrocarbons, and where hydrocarbons are unloaded. The pattern of hydrocarbon production is coordinated with feeding and with oocyte maturation in adults. In both adult females and nymphs, hydrocarbon synthesis is restricted to the abdominal integument. Nymphs retain newly formed hydrocarbons internally. Early in the last stadium the internal pool of hydrocarbons is largely associated with the hemolymph. Later, hydrocarbons accumulate in the fat body. Around mid-stadium the new cuticle begins to form and an increasing fraction of internal hydrocarbons associate with the pharate cuticle. The shuttling of hydrocarbons from sites of synthesis to fat body and then to the integument requires hemolymph transport. We isolated and characterized a high density lipophorin. Antibodies to lipophorin were generated and an ELISA was developed to titer lipophorin. We established that no hydrocarbon circulates unbound in the hemolymph, that all hemolymph hydrocarbon is bound to lipophorin, and that no other hemolymph proteins carry hydrocarbons. The capacity of lipophorin to accept newly synthesized hydrocarbons from integument was confirmed in vitro. The presence of lipophorin is mandatory for transfer of newly synthesized hydrocarbons to the hemolymph, a step that is necessary for hydrocarbon trafficking.. To study hydrocarbon transport by lipophorin to the oocytes, we determined hemolymph volume by inulin dilution, hydrocarbon titer by gas chromatography, lipophorin titer by ELISA, juvenile hormone titer by gas chromatography-mass spectrometry, and hydrocarbon content of the ovaries by gas chromatography. Results show that the ovary is a major deposition site for hydrocarbons, but only small amounts of lipophorin appear to enter the oocytes. We developed an in vitro system to study hydrocarbon uptake by oocytes, and showed that juvenile hormone stimulates hydrocarbon incorporation into oocytes. Adipokinetic hormone, a peptide released from the corpora cardiaca, stimulates conversion of stored triacylglycerol to diacylglycerol in insects that are capable of lipid-fueled flight. We examined the response of B. germanica to adipokinetic hormone and to hypertrehalosemic hormone. Neither stimulated either production of hydrocarbon or their uptake by lipophorin. A gas chromatography and fast Fourier transform study examined the biophysical properties of hydrocarbons. The melting temperature of oothecal hydrocarbons was highest > epicuticular hydrocarbons > hemolymph hydrocarbons. The cockroach ootheca is particularly well protected by an abundance of n-alkanes and its external hydrocarbons exhibit the highest melting temperature of any of the hydrocarbon blends. The female somehow delivers certain hydrocarbons to the egg case.

Impacts
This project is of basic value and of practical pest management significance. The cuticular wax layer is unique to arthropods. Because hydrocarbons play important functions, their trafficking is critical in microhabitat choice and foraging behavior. Cuticular hydrocarbons therefore are a prime target for the development of specific control technologies. The German cockroach is a major urban pest world-wide that can acquire, carry, and transfer pathogens

Publications

  • HOLBROOK G. L., J. ROEBUCK, C. B. MOORE and C. SCHAL. 1999. Prevalence and magnitude of insecticide resistance in the German cockroach (Dictyoptera, Blattellidae). In: Proceedings of the 3rd International Conference on Urban Pests (W. H. Robinson, F. Rettich and G. W. Rambo, Eds.), Graficke zavody Hronov, Czech Republic, pp. 141-145.
  • KOPANIC R. J. JR. and C. SCHAL. 1999. Coprophagy facilitates horizontal transmission of bait among cockroaches (Dictyoptera: Blattellidae). Environmental Entomology 28:431-438.
  • MUKHA D. V., B. M. WIEGMANN and C. SCHAL. 1999. Saltation changes within the ribosomal genes cluster during Blattella evolution. Doklady Akademii nauk (Doklady Physics: A journal of the Russian Academy of Sciences) 364:134-139.
  • SEVALA V., S. SHU, S. B. RAMASWAMY and C. SCHAL. 1999. Lipophorin of female Blattella germanica: Characterization and relation to hemolymph titers of juvenile hormone and hydrocarbons. Journal of Insect Physiology 45:431-441.
  • YOUNG H. P, J. A. S. BACHMANN, V. SEVALA and C. SCHAL. 1999. Site of synthesis, tissue distribution, and lipophorin transport of hydrocarbons in Blattella germanica (L.) nymphs. Journal of Insect Physiology 45:305-315.
  • YOUNG H. P, J. A. S. BACHMANN and C. SCHAL. 1999. Food intake in Blattella germanica (L.) nymphs affects hydrocarbon synthesis and its allocation in adults between epicuticle and reproduction. Archives of Insect Biochemistry and Physiology 41:214-224.


Progress 01/01/98 to 12/31/98

Outputs
Several important targets for developing novel, insect-specific pest control technologies have been investigated. Lipophorin, a multi-functional lipid carrier in insect blood transports hormones, pheromones, cuticular waxes, and other lipids. We have documented involvement of lipophorin in hydrocarbon transport in adults and immatures of the German cockroach, determined which tissues store hydrocarbons, and where hydrocarbons are unloaded. We showed that in both adult females and nymphs, hydrocarbon is synthesized only in the integument. The pattern of hydrocarbon production is coordinated with feeding and oocyte maturation. It gradually increases after the imaginal molt and only low amounts of hydrocarbon accumulate during 'pregnancy,' while feeding is low. The internal hydrocarbon titer decreased 58% after oviposition, suggesting deposition in the egg case. These patterns suggested that both the cuticle and the ovaries might be target sites for hydrocarbon deposition. Our results established unequivocally that no hydrocarbon circulates unbound in the hemolymph, that all hemolymph hydrocarbon is bound to high density lipophorin, and that no other hemolymph proteins carry hydrocarbon. In order to generalize our findings to other insects, we are also conducting studies with termites, flies, and moths. We developed a model system that will serve as a clear example of selective deposition of a subset of the lipophorin-bound hydrocarbons in specific tissues. The adult female tiger moth (Holomelina aurantiaca) simultaneously synthesizes short-chain hydrocarbons that serve as a volatile sex pheromone and long-chain hydrocarbons that are deposited on the epicuticle. All hydrocarbons are synthesized in association with the abdominal integument and then loaded onto hemolymph high-density lipophorin. 2-Methylheptadecane and related pheromone homologs of similar chain length are specifically deposited by Lp into tubular abdominal pheromone glands that in turn open and emit the pheromone near the ovipositor. Long-chain hydrocarbons, on the other hand, appear on the epicuticular surface; they are specifically deposited by lipophorin in the integument. This appears to be a unique system of spatial dissociation of short-chain and long-chain hydrocarbons, probably requiring receptors for specific hydrocarbon types at the appropriate target tissues. Structure-activity studies of the specificity of hydrocarbon uptake by high-density lipophorin and the pheromone gland are now in progress. We also evaluated the utility of pheromones in cockroach control in houses. A pheromone that we previously identified from the brown-banded cockroach, and synthesized, was shown to be a potent attractant in infested homes and laboratories. A slow-release formulation of this pheromone will serve as an effective pest monitoring tool. The role of coprophagous behavior was examined in cockroaches. Coprophagy can serve as an efficient delivery system to translocate pesticides from delivery sites to non-foraging cockroaches.

Impacts
(N/A)

Publications

  • CHIANG A. S., G. L. HOLBROOK, H. W. CHENG and C. SCHAL. 1998. Neural control of cell size in the corpora allata during the reproductive cycle of the cockroach Diploptera punctata (Dictyoptera: Blaberidae). Invertebrate Reproduction and Development 33:25-34.
  • HOLBROOK G. L., A. S. CHIANG, Y. J. LEE AND C. Y. LIN and C. SCHAL. 1998. Juvenile hormone biosynthesis in relation to corpus allatum development in embryos of the viviparous cockroach, Diploptera punctata. Invertebrate Reproduction and Development 33:69-79.
  • HOLBROOK G. L. and C. SCHAL. 1998. Social influences on larval development in the viviparous cockroach Diploptera punctata. Physiological Entomology 23:121-130.
  • LIANG D., A. ZHANG, R. J. KOPANIC JR., W. ROELOFS and C. SCHAL. 1998. Field and laboratory evaluation of female sex pheromone for detection, monitoring, and management of brownbanded cockroaches (Dictyoptera: Blattellidae). Journal of Economic Entomology 91:480-485.
  • SCHAL C, V. L. SEVALA, H. P. YOUNG and J. A. S. BACHMANN. 1998. Synthesis and transport of hydrocarbons: cuticle and ovary as target tissues. American Zoologist 38:382-393.
  • SCHAL C., V. SEVALA and R. T. CARDE. 1998. Novel and highly specific transport of a volatile sex pheromone by hemolymph lipophorin in moths. Naturwissenschaften 85:339-342.
  • TILLMAN J. A., G. L. HOLBROOK, P. L. DALLARA, C. SCHAL, D. L. WOOD, G. J. BLOMQUIST and S. J. SEYBOLD. 1998. Endocrine regulation of de novo aggregation pheromone biosynthesis in the pine engraver, Ips pini (Say) (Coleoptera: Scolytidae). Insect Biochemistry and Molecular Biology 28:705-715.
  • TREXLER J. D., C. S. APPERSON, and C. SCHAL. 1998. Laboratory and field evaluations of oviposition responses of Aedes albopictus and Aedes triseriatus (Diptera: Culicidae) to oak leaf infusions. Journal of Medical Entomology 35:967-976.


Progress 01/01/97 to 12/31/97

Outputs
Several important targets for developing novel, insect-specific pest control technologies have been investigated. Lipophorin, a multi-functional lipid carrier in insect blood transports hormones, pheromones, cuticular waxes, and other lipids. We have documented involvement of lipophorin in hydrocarbon transport in adults and immatures of the German cockroach, determined which tissues store hydrocarbons, and where hydrocarbons are unloaded. We showed that in immatures, hydrocarbons are synthesized only when food is available, stored in association with lipophorin, and unloaded onto the new adult cuticle before the molt. In the adult, lipophorin delivers hydrocarbons to eggs. Interfering with these functions could render cockroaches susceptible to dehydration. Lipophorin was also shown to bind an important regulator of development and reproduction, juvenile hormone. Using photoaffinity labeling and Scatchard analysis, binding was found to be specific, saturable and with high affinity to juvenile hormone III. Disruption of juvenile hormone transport would interfere with development and reproduction in insects. We also evaluated the utility of pheromones in cockroach control in houses. A pheromone that we previously identified from the brownbanded cockroach, and synthesized, was shown to be a potent attractant in infested homes and laboratories. A slow-release formulation of this pheromone will serve as an effective pest monitoring tool. The role of coprophagous behavior was examined in cockroaches.

Impacts
(N/A)

Publications

  • HOLBROOK G.L., A-S. CHIANG and C. SCHAL. 1997. Improved conditions for culture of biosynthetically active cockroach corpora allata. In Vitro Cellular and Developmental Biology - Animal 33:452-458.
  • KOPANIC R.J. JR. and C. SCHAL. 1997. Relative significance of direct ingestion and adult-mediated translocation of bait to German cockroach (Dictyoptera: Blattellidae) nymphs. Journal of Economic
  • SCHAL C., D. LIANG and G.J. BLOMQUIST. 1997. Neural and endocrine control of pheromone production and release in cockroaches. In: Insect Pheromone Research: New Directions (R. T. CARD and A. K. MINKS, Eds.), Chapman and Hall, New York, pp. 3-20.---
  • SCHAL C., G.L. HOLBROOK, J.A.S. BACHMANN and V.L. SEVALA. 1997. Reproductive biology of the German cockroach, Blattella germanica: Juvenile hormone as a pleiotropic master regulator. Archives of Insect Biochemistry and Physiology 35:405-426.---
  • SEVALA V.L., J.A.S. BACHMANN and C. SCHAL. 1997. Lipophorin: A hemolymph juvenile hormone binding protein in the German cockroach, Blattella germanica. Insect Biochemistry and Molecular Biology
  • TREXLER J.D., C.S. APPERSON and C. SCHAL. 1997. Diel oviposition patterns of Aedes albopictus (Skuse) and Aedes triseriatus (Say) in the laboratory and the field. Journal of Vector Ecology 22:64-70.---
  • YOUNG H.P. and C. SCHAL. 1997. Cuticular hydrocarbon synthesis in relation to feeding and developmental stage in Blattella germanica (L.) (Dictyoptera: Blattellidae) nymphs. Annals of the Entomological Society of America 90:655-663.---


Progress 01/01/96 to 12/30/96

Outputs
Several important targets for developing novel, insect-specific pest control technologies have been investigated. Lipophorin, a multi-functional lipid carrier in insect blood transports hormones, pheromones, cuticular waxes, and other lipids. We have documented involvement of lipophorin in hydrocarbon transport in adults and immatures of the German cockroach, determined which tissues store hydrocarbons, and where hydrocarbons are unloaded. We showed that in immatures, hydrocarbons are synthesized only when food is available, stored in association with lipophorin, and unloaded onto the new adult cuticle before the molt. In the adult, lipophorin acts as a reusable shuttle, delivering hydrocarbons to eggs; the embryos in turn use this maternal contribution to prevent desiccation. Interfering with these functions could render cockroaches susceptible to dehydration. Lipophorin was also shown to bind an important regulator of development and reproduction, juvenile hormone. Using photoaffinity labeling and Scatchard analysis, binding was found to be specific, saturable and with high affinity to juvenile hormone III. Disruption of juvenile hormone transport would interfere with development and reproduction in insects. We also evaluated the utility of pheromones in cockroach control in houses. A pheromone that we previously identified from the brownbanded cockroach, and synthesized, was shown to be a potent attractant in infested homes and laboratories. A slow-release formulation of this pheromone will.

Impacts
(N/A)

Publications

  • CHIANG, A- S., TSAI, W- H., HOLBROOK, G. L. and SCHAL, C. 1996. Control of cell proliferation in the corpora allata during the reproductive cycle of the cockroach Diploptera punctata. Arch. Insect Biochem. Physiol. 32:299-313. HOLBROOK, G.L.