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ARS Home » Northeast Area » Newark, Delaware » Beneficial Insects Introduction Research Unit » People & Locations » Keith Hopper
Keith R Hopper
Beneficial Insects Introduction Research Unit
Research Entomologist

Phone: (302) 731-7330 ext. 238
Fax: (302) 731-1397

501 SOUTH CHAPEL STREET
NEWARK , DE 197133814
Projects
Host Specificity and Systematics of Insect Biological Control Agents
In-House Appropriated (D)
  Accession Number: 429050
Genetics and Genomics of Host Specificity in Aphid Parasitoids
Interagency Reimbursable Agreement (I)
  Accession Number: 431522
Rapid Evolution in Biological Control: Implications for Safety and Effectiveness
Reimbursable Cooperative Agreement (R)
  Accession Number: 431337
Integrated Area-Wide Management of Soybean Aphid with Biological Control Introductions and Host Plant Resistance - Iowa
Non-Assistance Cooperative Agreement (S)
  Accession Number: 429119
Integrated Area-Wide Management of Soybean Aphid with Biological Control Introductions and Host Plant Resistance - Minnesota
Non-Assistance Cooperative Agreement (S)
  Accession Number: 429129
Integrated Area-Wide Management of Soybean Aphid with Biological Control Introductions and Host Plant Resistance - Ohio
Non-Assistance Cooperative Agreement (S)
  Accession Number: 429131

Publications (Clicking on the reprint icon Reprint Icon will take you to the publication reprint.)
Genomes of the Hymenoptera -
Branstetter, M.G., Childers, A.K., Cox-Foster, D.L., Hopper, K.R., Kapheim, K.M., Toth, A.L., Worley, K.C. 2018. Genomes of the Hymenoptera. Current Opinion in Insect Science. 25:65-75. https://doi.org/10.1016/j.cois.2017.11.008.
The genetic architecture of ecological adaptation: Intraspecific variation in host plant use by the lepidopteran crop pest Chloridea virescens -
Oppenheim, S.J., Gould, F.L., Hopper, K.R. 2017. The genetic architecture of ecological adaptation: Intraspecific variation in host plant use by the lepidopteran crop pest Chloridea virescens. Heredity. published online.
Parasitoid host ranges: comparing studies from the laboratory and field -
Heimpel, G.E., Hopper, K.R., Kaser, J.M., Miksanek, J., Bulgarella, M., Ramirez, I., Boulton, R.A. 2017. Parasitoid host ranges: comparing studies from the laboratory and field. International Symposium on Biological Control of Arthropods.
Host specificity of Aphelinus species collected from soybean aphid in Asia -
Hopper, K.R., Lanier, K., Rhoades, J.H., Hoelmer, K.A., Meikle, W.G., Heimpel, G.E., O'Neil, R.J., Voetglin, D.G., Woolley, J.B. 2017. Host specificity of Aphelinus species collected from soybean aphid in Asia. Biological Control. 115:55-73. https://doi.org/10.1016/j.biocontrol.2017.09.004.
Intraspecific variation in facultative symbiont infection among native and exotic pest populations: potential implications for biological control -
Desneux, N., Monticelli, L., Luo, C., Asplen, M.K., Brady, C.M., Heimpel, G.E., Hopper, K.R., Oliver, K.M., White, J.A. 2017. Intraspecific variation in facultative symbiont infection among native and exotic pest populations: potential implications for biological control. Biological Control. https://doi.org/10.1016/j.biocontrol.2017.1006.1007.
The defensive aphid symbiont Hamiltonella defensa affects host quality differently for Aphelinus glycinis versus Aphelinus atriplicis -
Hopper, K.R., Kuhn, K.L., Lanier, K., Rhoades, J.H., Oliver, K.M., White, J.A., Asplen, M.K., Heimpel, G.E. 2017. The defensive aphid symbiont Hamiltonella defensa affects host quality differently for Aphelinus glycinis versus Aphelinus atriplicis. Biological Control. doi:10.1016/j.biocontrol.2017.05.008.
Phased genotyping-by-sequencing enhances analysis of genetic diversity and reveals divergent copy number variants in maize -
Manching, H., Sengupta, S., Hopper, K.R., Polson, S.W., Ji, Y., Wisser, R.J. 2017. Phased genotyping-by-sequencing enhances analysis of genetic diversity and reveals divergent copy number variants in maize. Genes, Genomes, Genetics. 7(7):2161-2170. doi: 10.1534/g3.117.042036.
Host specificity of Aphelinus species considered for introduction to control Diuraphis noxia -
Hopper, K.R., Lanier, K., Rhoades, J., Kondos, R., Coutinot, D., Mercadier, G., Ramualde, N., Roche, M., Woolley, J.B., Heraty 2017. Host specificity of Aphelinus species considered for introduction to control Diuraphis noxia. Biological Control. 107:21-32.
Variation in genome size and karyotype among closely related parasitoids of aphids -
Gokhman, V.E., Kuhn, K.L., Woolley, J.B., Hopper, K.R. 2017. Variation in genome size and karyotype among closely related parasitoids of aphids. Comparative Cytogenetics. 11:97-117.
Revision of the Asychis species group of Aphelinus (Hymenoptera: Aphelinidae) -
Xanthe, S.A., Woolley, J.B., Hopper, K.R. 2017. Revision of the Asychis species group of Aphelinus (Hymenoptera: Aphelinidae). Journal of Hymenoptera Research. 54:1-32.
A new species of oobius trjapitzin (hymenoptera:encyrtidae) from the russian far east that parasitizes eggs of emerald ash borer (coleoptera:buprestidae) -
Yao, Y., Duan, J.J., Hopper, K.R., Moltern, J.L., Gates, M.W. 2016. A new species of oobius trjapitzin (hymenoptera:encyrtidae) from the russian far east that parasitizes eggs of emerald ash borer (coleoptera:buprestidae). Annals of the Entomological Society of America. 109(4):629-638. doi: 10.1093/aesa/saw022.
A new species of genus Oobius (Hymenoptera: Encyrtidae) from the Russian Far East that parasitizes eggs of Emerald Ash Borer -
Yao, Y., Duan, J.J., Hopper, K.R., Mottern, J.L., Gates, M.W. 2016. A new species of genus Oobius (Hymenoptera: Encyrtidae) from the Russian Far East that parasitizes eggs of Emerald Ash Borer. Annals of the Entomological Society of America. 1-10: doi: 10.1093/aesa/saw022.
Arthropod genomics research in the United States Department of Agriculture-Agricultural Research Service: Current impacts and future prospects -
Coates, B.S., Poelchau, M.F., Childers, C., Evans, J.D., Handler, A.M., Guerrero, F., Skoda, S.R., Hopper, K.R., Wintermantel, W.M., Ling, K., Hunter, W.B., Oppert, B.S., Perez De Leon, A.A., Hackett, K.J., Shoemaker, D.D. 2015. Arthropod genomics research in the United States Department of Agriculture-Agricultural Research Service: Current impacts and future prospects. Trends in Entomology. 11(1):1-27.
Specialization of bacterial endosymbionts that protect aphids from parasitoids -
Asplen, M.K., Bano, N., Brady, C.M., Desneux, N., Hopper, K.R., Malouines, C., Oliver, K.M., White, J.A., Heimpel, G.E. 2014. Specialization of bacterial endosymbionts that protect aphids from parasitoids. Ecological Entomology. 39: 736-739.
Factors limiting the spread of the protective symbiont HAMILTONELLA DEFENSA in the aphid APHIS CRACCIVORA -
Dykstra, H.R., Weldon, S.R., White, J.A., Hopper, K.R., Heimpel, G.E., Asplen, M.K., Oliver, K.M. 2014. Factors limiting the spread of the protective symbiont HAMILTONELLA DEFENSA in the aphid APHIS CRACCIVORA. Applied and Environmental Microbiology. 80: 5818-5827.
Parasitism of soybean aphid by APHELINUS species on soybean susceptible versus resistant to the aphid -
Hopper, K.R., Diers, B.W. 2014. Parasitism of soybean aphid by APHELINUS species on soybean susceptible versus resistant to the aphid. Biological Control. 76:101-106.
Worldwide populations of APHIS CRACCIVORA have diverse facultative bacterial symbionts -
Brady, C.M., Asplen, M.K., Heimpel, G.E., Hopper, K.R., Linnen, C.R., Oliver, K.M., Wulff, J.A., White, J.A., Desneux, N. 2013. Worldwide populations of APHIS CRACCIVORA have diverse facultative bacterial symbionts. Microbial Ecology. 67:195-204.
Next-generation genome sequencing and assembly provides tools for phylogenetics and identification of closely related species of Spathius, parasitoids of Agrilus planipennis (emerald ash borer) -
Kuhn, K.L., Duan, J.J., Hopper, K.R. 2013. Next-generation genome sequencing and assembly provides tools for phylogenetics and identification of closely related species of Spathius, parasitoids of Agrilus planipennis (emerald ash borer). Biological Control. 66:77-82.
Is parasitoid acceptance of different host species dynamic? -
Hopper, K.R., Prager, S., Heimpel, G.E. 2013. Is parasitoid acceptance of different host species dynamic?. Functional Ecology. 10.1111/1365-2435.12107.
The genetic architecture of a complex ecological trait: host plant use in the specialist moth, HELIOTHIS SUBFLEXA Reprint Icon -
Oppenheim, S.J., Gould, F.L., Hopper, K.R. 2012. The genetic architecture of a complex ecological trait: host plant use in the specialist moth, HELIOTHIS SUBFLEXA. Evolution. DOI: 10.1111/j.1558-5646.2012.01712.x.
An identification key to species in the mali complex of Aphelinus (Hymenoptera, Chalcidoidea) with descriptions of three new species -
Hopper, K.R., Woolley, J.B., Hoelmer, K.A., Wu, K., Lee, S. 2012. An identification key to species in the mali complex of Aphelinus (Hymenoptera, Chalcidoidea) with descriptions of three new species. Journal of Hymenoptera Research. 26:73-96.
Outcrossing and crossbreeding recovers deteriorated traits in laboratory cultured Steinernema carpocapsae nematodes -
Chaston, J.M., Dillman, A.R., Shapiro Ilan, D.I., Bilgrami, A., Gaugler, R., Hopper, K.R., Adams, B.J. 2011. Outcrossing and crossbreeding recovers deteriorated traits in laboratory cultured Steinernema carpocapsae nematodes. International Journal for Parasitology. 41:801-809.
European buckthorn and Asian soybean aphid as components of an extensive invasional meltdown in North America Reprint Icon -
Heimpel, G.E., Frelich, L.E., Landis, D.A., Hopper, K.R., Hoelmer, K.A., Sezen, Z., Asplen, M.K., Wu, K. 2010. European buckthorn and Asian soybean aphid as components of an extensive invasional meltdown in North America. Biological Invasions. DOI: 10.1007/s10530-010-9736-5.
French wasps in the New World: experimental biological control introductions reveal a demographic Allee effect -
Fauvergue, X., Hopper, K.R. 2009. French wasps in the New World: experimental biological control introductions reveal a demographic Allee effect. Population Ecology. 51(3):385–397
Multifaceted determinants of host specificity in an aphid parasitoid -
Desneux, N., Barta, R.J., Hoelmer, K.A., Hopper, K.R., Heimpel, G.E. 2009. Multifaceted determinants of host specificity in an aphid parasitoid. Oecologia. 160:387-398.
GENETICS OF HOST RANGE IN LEPIDOPTERA -
Hopper, K.R., Oppenheim, S.J. 2009. GENETICS OF HOST RANGE IN LEPIDOPTERA. In: Goldsmith, M., Marec, F., Editors. Molecular Biology and Genetics of Lepidoptera. Boca Raton, Florida: CRC Press. 195-217.
PREDICTING INSECT DISTRIBUTIONS FROM CLIMATE AND HABITAT DATA -
Ulrichs, C., Hopper, K.R. 2008. Predicting insect distributions from climate and habitat data. BioControl. 10.1007/s10526-007-9143-8, 1-14.
Introduction of Exotic Natural Enemies of Invasive Insect Pests in the USA: Soybean aphid (Aphis glycines Matsumura) as a current example -
Hoelmer, K.A., Hopper, K.R. 2007. Introduction of Exotic Natural Enemies of Invasive Insect Pests in the USA: Soybean aphid (Aphis glycines Matsumura) as a current example. Proceedings, International Symposium on Plant Quarantine & Exotic Insect Pest Management. Korean Society of of Applied Entomology & National Plant Quarantine Services of Korea, 18-19 October, 2007, YangPyeong, Korea. Pp 93-105.
Parasitism of the soybean aphid Aphis glycines by Binodoxys communis: the role of aphid defensive behavior and parasitoid reproductive performance -
Wyckhuys, K.A.G., Stone, L., Desneux, N., Hoelmer, K., Hopper, K.R., and Heimpel, G.E. 2008. Parasitism of the soybean aphid Aphis glycines by Binodoxys communis: the role of aphid defensive behavior and parasitoid reproductive performance. Bulletin of Entomological Research. 98:361-370.
Molecular phylogenetics and reproductive incompatibility in a complex of cryptic species of aphid parasitoids -
Heraty, J.M., Woolley, J.B., Hopper, K.R., Hawks, D.L., Kim, J., Buffington, M. 2007. Molecular phylogenetics and reproductive incompatibility in a complex of cryptic species of aphid parasitoids. Molecular Phylogenetics and Evolution. doi:10.1016/j.ympev.2007.06.021.
Predicting potential ecological impact of soybean aphid biological control introductions -
Wyckhuys, K.A., Hopper, K.R., Wu, K., Straub, C., Gratton, C., Heimpel, G.E. 2007. Predicting potential ecological impact of soybean aphid biological control introductions. Biocontrol News and Information. 28(2):30-34
Population dynamics of APHIS GLYCINES and impact of natural enemies in northern China -
Miao, J., Wu, K., Hopper, K.R., Li, G. 2007. Population dynamics of APHIS GLYCINES (Hompotera: Aphididae) and impact of natural enemies in northern China. Environmental Entomology. 36:840-848.
Trait Modification in Entomopathogenic Nematodes -
Shapiro Ilan, D.I., Gaugler, R., Adams, B., Hopper, K.R. 2007. Trait Modification in Entomopathogenic Nematodes. Society of Invertebrate Pathology Annual Meeting, August 12-16, 2007, Quebec City, Canada. p. 71-72. Available: http://www.sipweb.org/Meeting_Abstracts/2007abstracts.pdf.
HOST CHOICE BY APHIDIUS COLEMANI: EFFECTS OF PLANTS, PLANT-APHID COMBINATIONS AND THE PRESENCE OF INTRAGUILD PREDATORS -
Bilu, E., Hopper, K.R., Coll, M. 2006. Host choice by aphidius colemani: effects of plants, plant-aphid combinations and the presence of intraguild predators. Ecological Entomology. 31:331-336.
SINGLE-LOCUS COMPLEMENTARY SEX DETERMINATION ABSENT IN HETEROSPILUS PROSOPIDIS (HYMENOPTERA: BRACONIDAE) -
Wu, Z., Hopper, K.R., Ode, P.J., Fuester, R.W., Tuda, M., Heimpel, G.E. 2005. Single-locus complementary sex determination absent in heterospilus prosopidis (hymenoptera: braconidae). Heredity. 95: 228-234.
GENETICS: RELATION OF LOCAL POPULATIONS TO THE WHOLE "SPECIES" - IMPLICATIONS FOR HOST RANGE TESTS -
Hopper, K.R., Farias, A.M., Woolley, J.B., Heraty, J.M., Britch, S.C. 2005. Genetics: relation of local populations to the whole "species" - implications for host range tests. Second International Symposium on Biological Control of Arthropods. p 665-671.
RISKS OF INTERBREEDING BETWEEN SPECIES USED IN BIOLOGICAL CONTROL AND NATIVE SPECIES AND METHODS FOR EVALUATING ITS OCCURRENCE AND IMPACT -
Hopper, K.R., Britch, S.C., Wajnberg, E. 2006. Risks of interbreeding between species used in biological control and native species and methods for evaluating its occurrence and impact. Pp. 78-97 D. Babendreier, F. Bigler and U. Kuhlmann, eds. Environmental Impact of Invertebrates for Biological Control of Arthropods: Methods and Risk Assessment. CABI Biosciences, London.
STABILIZATION OF BENEFICIAL TRAITS IN HETERORHABDITIS BACTERIOPHORA THROUGH CREATION OF INBRED LINES -
Bai, C., Shapiro Ilan, D.I., Gaugler, R., Hopper, K.R. Stabilization of beneficial traits in heterorhabditis bacteriophora through creation of inbred lines. Biological Control. 2005. 32:220-227.
GENETIC IMPROVEMENT FOR PREVENTION OF BENEFICIAL TRAIT DETERIORATION IN HETERORHABDITIS BACTERIOPHORA THROUGH CREATION OF INBRED LINES -
Bai, C., Shapiro Ilan, D.I., Gaugler, R., Hopper, K.R. 2004. Genetic improvement for prevention of beneficial trait deterioration in heterorhabditis bacteriophora through creation of inbred lines. Society for Invertebrate Pathology Annual Meeting Proceedings. p.104.
REPRODUCTIVE COMPATIBILITY AND GENETIC VARIATION BETWEEN TWO STRAINS OF APHELINUS ALBIPODUS (HYMENOPTERA: APHELINIDAE), A PARASITOID OF THE SOYBEAN APHID, APHIS GLYCINES (HOMOPTERA : APHIDIDAE) -
Wu, Z., Hopper, K.R., O'Neil, R., Voegtlin, D., Prokrym, D., Heimpel, G.E. 2004. Reproductive compatibility and genetic variation between two strains of Aphelinus albipodus (Hymenoptera: Aphelinidae), a parasitoid of the soybean aphid, Aphis Glycines (Homoptera: Aphididae). Biological Control. 31(3): 311-319.
OVIPOSITION VS. OFFSPRING FITNESS IN APHIDIUS COLEMANI PARASITIZING DIFFERENT APHID SPECIES. ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA -
Ode, P.J., Hopper, K.R., Coll, M. 2004. Oviposition vs. offspring fitness in Aphidius colemani parasitizing different aphid species. Entomologia Experimentalis et Applicata. Entomologia Experimentalis et Applicata. 115(2): 303-310.
USING THE LITERATURE TO EVALUATE PARASITOID HOST RANGES: A CASE STUDY OF MACROCENTRUS GRANDII (HYMENOPTERA: BRACONIDAE) INTRODUCED INTO NORTH AMERICA TO CONTROL OSTRINIA NUBILALIS (LEPIDOPTERA: CRAMBIDAE) -
De Nardo, E., Hopper, K.R. 2004. Using the literature to evaluate parasitoid host ranges: a case study of macrocentrus grandii (Hymenoptera: Braconidae) introduced into North America to control Ostrinia nubilalis (Lepidoptera: Crambidae). Biocontrol. 31(3) 280-295.
POPULATION DYNAMICS OF APHIS GLYCINES AND ITS NATURAL ENEMIES IN SOYBEAN IN NORTHERN CHINA -
Liu, J., Wu, K., Hopper, K.R., Zhao, K. 2004. Population dynamics of aphis glycines and its natural enemies in soybean in northern china. Annals of the Entomological Society of America. 97(2):235-9
PROSPECTS FOR IMPORTATION BIOLOGICAL CONTROL OF THE SOYBEAN APHID: ANTICIPATING POTENTIAL COSTS AND BENEFITS -
Heimpel, G.E., Ragsdale, D.W., Venette, R., Hopper, K.R., O'Neil, R.J., Rutledge, C.E., Wu, Z. 2004. Prospects for importation biological control of the soybean aphid: anticipating potential costs and benefits. Annals of the Entomological Society of America. 97(2):249-258 (2004)
COMPLEMENTARY SEX DETERMINATION IN HYMENOPTERAN PARASITOIDS AND ITS IMPLICATIONS FOR BIOLOGICAL CONTROL -
Wu, Z., Hopper, K.R., Ode, P.J., Fuester, R.W., Chen, J., Heimpel, G.E. 2003. Complementary Sex Determination in Hymenopteran Parasitoids and its implications for Biological Control. Entomologia Sinicae. 10(2):81-93.
USDA-ARS RESEARCH ON BIOLOGICAL CONTROL OF ARTHROPODS -
Hopper, K.R. USDA-ARS research on biological control of arthropods. Pest Management Science 59:643-653
MALE-BIASED SEX RATIOS IN LABORATORY REARINGS OF GYPSY MOTH PARASITOIDS -
Fuester, R.W., Swan, K.S., Taylor, P.B., Hopper, K.R., Ode, P.J. 2004. Male-biased sex ratios in laboratory rearings of gypsy moth parasitoids. pp. 24-27. In S. Fosbroke and K. Gottshalk (eds.), Proceedings, United States Department of Agricultural Interagency Research Forum on gypsy moths and other invasive species 2002: 2002 January 15-18; Annapolis, MD. Gen. Tech. Rep. NE-300 Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northeastern Research Station. 116p.
INRODUCTION AND ESTABLISHMENT OF PARASITOIDS FOR THE BIOLOGICAL CONTROL OF THE APPLE ERMINE MOTH, YPONOMEUTA MALINELLUS (LEPIDOPTERA: YPONOMEUTIDAE), IN THE PACIFIC NORTHWEST -
Unruh, T.R., Short, R.E., Herard, F., Chen, K., Hopper, K.R., Pemberton, R.W., Lee, J.H., Ertle, L.R., Swan, K.S., Fuester, R.W. 2003. Inroduction and establishment of parasitoids for the biological control of the apple ermine moth, Yponomeuta malinellus (Lepidoptera: Yponomeutidae), in the Pacific Northwest. Biological Control. 28:332-345.
INTRODUCTIONS OF NON-INDIGENOUS ORGANISMS: RESEARCH NEEDS TO EVALUATE COSTSAND BENEFITS -
Ewel, J.J., O'Dowd, D.J., Bergelson, J., Daehler, C.C., D'Antonio, C.M., Gómez, L., Gordon, D.R., Hobbs, R.J., Holt, A., Hopper, K.R., Hughes, C.E., Lahart, M., Leakey, R.B., Lee, W.G., Loope, L.L., Lorence, D.H., Louda, S.M., Lugo, A.E., Mcevoy, P.B., Richardson, D.M., Vitousek, P.M. 1999. Introductions of non-indigenous organisms: research needs to evaluate costsand benefits. Bioscience. 49:619-630.
RISK-SPREADING AND BET-HEDGING IN INSECT POPULATION BIOLOGY -