Grzegorz (Greg) Krawczyk, Ph.D.

Extension Tree Fruit Entomologist


    Insect plant interactions
    Integrated pest management
    Biological control
    Tree fruit insect pests
    Insects rearing
    Laboratory and field bioassays
    Invasive insect pests
    Pesticide resistance



    About Me

    Research Activities & Interests:

    Integrated pest management in agricultural ecosystems

    • Sustainable fruit production methods
    • Biology and management of tree fruit insect pests
    • Pesticide resistance management in agricultural ecosystems
    • Phytophagous and predatory mite management in orchard ecosystems
    • Insect rearing techniques/laboratory bioassays

    Recent Publications:

    • Rice, K. B, C. Bergh, E. Bergman, D. Biddinger, C. Dieckhoff, G. Dively, H. Fraser, T. Gariepy, G. Hamilton, T. Haye, A. Herbert, K. Hoelmer, C. Hooks, A. Jones, G. Krawczyk, T. Kuhar, W. Mitchell, A. Nielsen, D. Pfeiffer, M. Raup, C. Rodriguez-Saona, P. Shearer, P. Shrewsbury, D. Vengugopal, J. Whalen, N. Wiman, T. Leskey, and J. Tooker. 2014. Biology, Ecology, and Management of Brown Marmorated Stink Bug (Halyomorpha halys). Journal of Pest Management. Vol 5 (3): DOI:

      Shimat, J., J. W. Stallings, T. C. Leskey, G. Krawczyk, D. Polk, B. Butler and J.C. Bergh. 2014. Spatial Distribution of Brown Marmorated Stink Bug (Hemiptera: Pentatomidae) Injury at Harvest in Mid –Atlantic Apple Orchards. J. Econ. Entomol. 107(5): 1839-1848

    • Krawczyk,G, L. A. Hull and M. E. Reed. 2012. Successes and Challenges with adoption of whole farm mating disruption programs by commercial fruit growers in Eastern United States – a Pennsylvania perspective. IOBC/wprs Bulletin Vol.74: 65-71
    • Leskey, T.C., G.C. Hamilton, A.L. Nielsen, D.F. Polk, C.Rodriguez-Saona, J.C/ Bergh, D. A. Herbert, T.P. Kuhar, D. Pfeiffer, G. Dively, C.R.R. Hooks, M.J. Raupp, P.M. Shrewsbury, G. Krawczyk, P.W. Shearer, J. Whalen, C. Koplinka-Loehr, E. Myers, D. Inkley, K.A. Hoelmer, D-Y. Lee, and S.E. Wright. 2012. Pest Status of the Brown Marmorated Stink Bug, Halyomorpha halys (Stål), in the USA. Outlooks on Pest Management. DOI: 10.1564/23aug00: 1-9.
    • Bohnenblust, E., L. A. Hull, G. Krawczyk, and N. K. Joshi. 2011. Capture of two moth species in traps placed at different heights in sex pheromone treated apple orchards. J. Entomol. Sci. 46(3): 223-231.
    • Bohnenblust, E., L. A. Hull, and G. Krawczyk. 2011. A comparison of various mating disruption technologies for control of two internally feeding Lepidoptera in apples. Entomologia Experimentalis et Applicata. DOI: 10.1111/j.1570-7458.2010.01089.x
    • Joshi N. K., L.A. Hull, E.G. Rajotte, G. Krawczyk, E. Bohnenblust (2011). Evaluating sex- pheromone- and kairomone-based lures for attracting codling moth adults in mating disruption versus conventionally managed apple orchards in Pennsylvania. Pest Management Science. DOI 10.1002/ps.2194.
    • Brown, M. W., C. R. Mathews and G. Krawczyk. 2010. Extrafloral nectar in an Apple Ecosystem to Enhance Biological Control. J. Econ. Entomol. 103(5): 1657-1664.
    • Brown, M. W., C. R. Mathews and G. Krawczyk. 2010. Analyzing the results of a biodiversity experiment: Enhancing parasitism of Platynota idaeusalis (Lepidoptera: Tortricidae) IOBC/wprs Bulletin Vol 54: 13-14.
    • Krawczyk, G., L. A. Hull, E. Bohnenblust. 2010. Utilization of Mating Disruption and Codling Moth Granulosis virus (CMGV) in Conventional Commercial Apple Orchards in Pennsylvania, USA. IOBC/wprs Bulletin Vol 54: 71-74
    • Agnello, A., A. Atanassov, J. C. Bergh, D. J. Biddinger, L. J. Gut, M. J. Haas, J. K. Harper, H. W. Hogmire, L. A. Hull, L. F. Kime, G. Krawczyk, P. S. McGhee, J. P. Nyrop, W. H. Reissig, P. W. Shearer, R. W. Straub, R. T. Villanueva, and J. F. Walgenbach. 2009. Reduced-risk pest management programs for eastern U.S. apple and peach orchards: a 4–year regional project. American Entomologist 55(3): 184-197.
    • Myers, C.T., G. Krawczyk and A.M. Agnello. 2009. Response of Tortricid Moths and Non-Target Insects to Pheromone Trap Color in Commercial Apple Orchards. J. Entomol. Science. 44(1): 69-77
    • Joshi, N. K., L. A. Hull, G. Krawczyk, and E. G. Rajotte. 2008. Field results of mating disruption technologies for the control of codling moth, Cydia pomonella (L.), and oriental fruit moth, Grapholita molesta (Busck) in Pennsylvania apple orchards. Aspects of Applied Biology (84) 153-161.
    • Myers, C. T., L. A. Hull and G. Krawczyk. 2007. Effects of orchard host plants (apple and peach) on development of Oriental fruit moth (Lepidoptera: Tortricidae). J. Econ. Entomol. 100(2): 421-430
    • Myers, C. T., Hull, L. A., and G. Krawczyk. 2006. Comparative survival rates of Oriental fruit moth (Lepidoptera: Tortricidae) larvae on shoots and fruit of apple and peach. J. Econ. Entomol. 99(4): 1299-1309.
    • Myers, C. T., L. A. Hull and G. Krawczyk. 2006. Early-season host plant fruit impact on reproductive parameters of the oriental fruit moth (Lepidoptera: Tortricidae). Journal of Entomological Science. 41(1): 65-74.
    • Myers, C. T., L. A. Hull and G. Krawczyk. 2006. Effects of orchard host plants on the oviposition preference of the Oriental fruit moth (Lepidoptera: Tortricidae). J. Econ. Entomol. 99(4): 1176-1183.
    • Myers, C. T., L. A. Hull, and G. Krawczyk. 2006 Seasonal and cultivar associated variation in the oviposition behavior of the Oriental fruit moth, (Lepidoptera: Tortricidae) adults and feeding behavior of neonate larvae in apples. J. Econ Entomol. 99(2): 349-358.
    • Hong, C., B. McPheron, G. Krawczyk and L. A. Hull. 2003. Laboratory evaluation of surface residue toxicity of insecticides to apple maggot flies. International Pest Control 45(2): 92-93, 97


    Ph. D. (1996) Michigan State University M. Sc. (1986) Agricultural University, Lublin, Poland