University of Kentucky UKnowledge Theses and Dissertations--Entomology Entomology 2016 EFFECTS OF LANDSCAPE, INTRAGUILD INTERACTIONS, AND A NEONICOTINOID ON NATURAL ENEMY AND PEST INTERACTIONS IN SOYBEANS Hannah J. Penn University of Kentucky, [email protected] Author ORCID Identifier: http://orcid.org/0000-0002-3692-5991 Digital Object Identifier: https://doi.org/10.13023/ETD.2016.441 Right click to open a feedback form in a new tab to let us know how this document benefits ou.y Recommended Citation Penn, Hannah J., "EFFECTS OF LANDSCAPE, INTRAGUILD INTERACTIONS, AND A NEONICOTINOID ON NATURAL ENEMY AND PEST INTERACTIONS IN SOYBEANS" (2016). Theses and Dissertations-- Entomology. 30. https://uknowledge.uky.edu/entomology_etds/30 This Doctoral Dissertation is brought to you for free and open access by the Entomology at UKnowledge. It has been accepted for inclusion in Theses and Dissertations--Entomology by an authorized administrator of UKnowledge. For more information, please contact [email protected]. STUDENT AGREEMENT: I represent that my thesis or dissertation and abstract are my original work. Proper attribution has been given to all outside sources. I understand that I am solely responsible for obtaining any needed copyright permissions. I have obtained needed written permission statement(s) from the owner(s) of each third-party copyrighted matter to be included in my work, allowing electronic distribution (if such use is not permitted by the fair use doctrine) which will be submitted to UKnowledge as Additional File. I hereby grant to The University of Kentucky and its agents the irrevocable, non-exclusive, and royalty-free license to archive and make accessible my work in whole or in part in all forms of media, now or hereafter known. I agree that the document mentioned above may be made available immediately for worldwide access unless an embargo applies. I retain all other ownership rights to the copyright of my work. I also retain the right to use in future works (such as articles or books) all or part of my work. I understand that I am free to register the copyright to my work. REVIEW, APPROVAL AND ACCEPTANCE The document mentioned above has been reviewed and accepted by the student’s advisor, on behalf of the advisory committee, and by the Director of Graduate Studies (DGS), on behalf of the program; we verify that this is the final, approved version of the student’s thesis including all changes required by the advisory committee. The undersigned agree to abide by the statements above. Hannah J. Penn, Student Dr. John J. Obrycki, Major Professor Dr. Charles Fox, Director of Graduate Studies EFFECTS OF LANDSCAPE, INTRAGUILD INTERACTIONS, AND A NEONICOTINOID ON NATURAL ENEMY AND PEST INTERACTIONS IN SOYBEANS _________________________________ DISSERTATION _________________________________ A dissertation submitted in partial fulfillment of the Requirements for the degree of Doctor of Philosophy in Entomology in The College of Agriculture, Food and Environment At the University of Kentucky By Hannah Joy Penn Lexington Kentucky Director: Dr. John J. Obrycki, Professor of Entomology Lexington Kentucky 2016 Copyright © Hannah Joy Penn 2016 ABSTRACT OF DISSERTATION EFFECTS OF LANDSCAPE, INTRAGUILD INTERACTIONS, AND A NEONICOTINOID ON NATURAL ENEMY AND PEST INTERACTIONS IN SOYBEANS Demand for food, fuel, and fiber has been increasing, escalating the intensification of agriculture during the past fifty years. A more comprehensive understanding of the impact of landscapes on sustainable agriculture production is required to meet the continual increase in human demand. This not only includes how chemical inputs are used but also how cultivated and surrounding landscapes are managed for ecosystem services. This research explains how land cover on landscape and farm scales impact ant and spider-mediated pest suppression. I successfully developed and optimized molecular methods to test ant gut contents from both laboratory and field-caught specimens. A multi-year field study indicated that spatial scale played a significant role in both ant and pest abundance and diversity when land cover at the landscape scale was analyzed, where an increase in scale generally correlated with an increase in the intensity of the relationship between landscape fragmentation and community response. I found that ant and pest populations can potentially be managed at the landscape scale via specific cover types and habitat fragmentation. Farm scale field margin composition significantly influenced spider and pest within field abundances and spatial associations, particularly early in the season. In a field cage study, ants were found to interfere with reductions in pest-induced leaf damage caused by spiders within the soybean system despite the fact that the pest was non-honeydew producing. Finally, I found that chemical disturbance via imidacloprid and fungicide seed treatments did not impact pest populations or ant predation rates but did significantly increase ant diversity by decreasing the abundance of a dominant ant species. However, there were impacts found on ant individuals within a lab mesocosm where imidacloprid induced sub-lethal intoxication but fungicides were lethal to Tetramorium caespitum. KEYWORDS: Agroecosystem, Araneae, Food Webs, Formicidae, Landscape Ecology ___Hannah J. Penn _______ ___December 2, 2016____________________ Date EFFECTS OF LANDSCAPE, INTRAGUILD INTERACTIONS, AND A NEONICOTINOID ON NATURAL ENEMY AND PEST INTERACTIONS IN SOYBEANS By Hannah Joy Penn ___John Obrycki ___ Director of Dissertation __Charles Fox__ ________________ Director of Graduate Studies ___ December 2, 2016_______________ THIS WORK IS DEDICATED TO MY PARENTS WHO ENCOURAGED ME TO DEVOTE MYSELF, EVEN AS A CHILD, TO MY ENTOMOLOGICAL ENDEAVORS. ACKNOWLEDGMENTS The following dissertation, while an individual work, benefited from the insights and direction of many people. First my Dissertation Chair, Dr. John Obrycki, who exhibits the leadership and scholarship to which I aspire, particularly in times of academic crisis. In addition, laboratory technician and fellow student Kacie Athey provided technical training, comments on experimental designs, assistance with experimental execution, and invaluable thoughts on every presentation and paper developed from this dissertation. Dr. Katelyn Kowles, Dr. Michael Sitvarin, Dr. Jamin Dreyer, Dr. Eric Chapman, and Dr. Brian Lee also provided timely and instructive comments on projects and papers during the dissertation process. I would also like to thank Dr. Douglas Johnson, Dr. Chad Lee, and Amanda Martin for assisting in the farmer recruitment and the on-farm research aspects of this dissertation. I would also like to thank Dr. Gary Coovert for ant identification assistance and Dr. Mary Gardiner and Dr. Dave Crowder for helpful comments regarding GIS. I wish to thank the complete Dissertation Committee, and outside reader, respectively: Dr. Ricardo Bessin, Dr. Daniel Potter, Dr. John Snyder, and Dr. Brian Lee. In addition to the technical and thought-provoking comments from those cited above, I was equally supported by friends and family. My professional and personal associate, Jerrod Penn, provided encouragement, collaborative projects, the sushi and bagels required for moral and physical stamina throughout the dissertation process as well as a sounding board for ideas, statistical analyses, and grievances. My mother, Rita McKenrick, worked tirelessly since I was in middle school to ensure that I had every professional opportunity that I could ever require. My father, Daniel McKenrick fielded untimely phone calls regarding unconventional experimental engineering and execution. Finally, I wish to thank the growers who graciously allowed me to sample their fields, discuss their farming histories, and drink coffee in their homes. Their willingness to assist an unknown student allowed this dissertation to come to completion. vii Table of Contents ACKNOWLEDGMENTS ...................................................................................... vii Table of Tables .................................................................................................... xii Table of Figures .................................................................................................. xiv Chapter 1 INTRODUCTION ................................................................................. 1 1.1 General Background ................................................................................... 2 1.1.1 Soybean Production .............................................................................. 2 1.1.2 Insect Pests of Soybean ....................................................................... 3 1.2 Biological Control ........................................................................................ 3 1.2.1 Importance of Generalist Predators ...................................................... 4 1.2.2 Intraguild Competition ........................................................................... 7 1.3 Molecular Gut Content Analysis .................................................................. 8 1.4 Landscape Ecology ..................................................................................... 9 1.4.1 Impact of Landscape on Biodiversity................................................... 10 1.4.2 Landscape Impacts on Biological Control ........................................... 11 Chapter 2 OVERCOMING PCR INHIBITION DURING DNA-BASED GUT CONTENT ANALYSIS OF ANTS ......................................................................