TOWARDS THE DEVELOPMENT OF AN INTEGRATED PEST MANAGEMENT PROGRAM FOR STRAWBERRIES: INVESTIGATION OF CULTIVAR SUSCEPTIBILITY TO TWOSPOTTED SPIDER MITES (TETRANYCHUS URTICAE KOCH) AND STING NEMATODES (BELONOLAIMUS LONGICAUDATUS RAU) AND INTEGRATION OF THE PREDATORY MITE (NEOSEIULUS CALIFORNICUS MCGREGOR) AND CHEMICAL TACTICS By OMOTOLA G. OLANIYI A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2018 1 © 2018 Omotola G. Olaniyi 2 To God and my boys: Ademola, Jedidiah, and Zuriel 3 ACKNOWLEDGMENTS I am sincerely thankful to my advisor, Dr. Oscar Liburd for his guidance, advice, and support throughout the course of my study. I appreciate the effort and time he invested in getting this dissertation finished, with useful comments and edits. I would like to thank my committee members, Dr. Carlene Chase, Dr. Dakshina Seal, and Dr. Tesfamariam Mengistu for their constant support, patience, and adequate help. I am grateful to Dr. Chase for her promptness in responding to my emails, providing feedback, meeting with me to clarify issues about my field work, and caring about my personal and family life. I am thankful to all my committee members for the cordial relationships they share among themselves, which provided me with a conducive atmosphere to express myself and conduct the experiments. I thank Dr. Phil Koehler for his constant encouragement, guidance, and mentorship at the crucial time that I needed it most. I appreciate Dr. Dan Hahn for the constant words of wisdom, advice, and encouragement that kept me going even in difficult times. I am grateful to Dr. Jennifer Gillett-Kaufman for helping me to be a better writer and the approving smiles that motivated me. I am grateful to Dr. Richard Mankin for his genuine interest in my success, and Dr. Alex Habteweld for his help with processing nematode samples and identifying some nematodes. I appreciate Dr. Salvador Gezan, Dr. Lazarus Mramba, Dr. Mohammed Sallam, Dr. Edzard van Santen, and Dr. James Colee of IFAS Statistical consulting for their tremendous help with data analysis and answering all my questions. I thank Dr. Henry Fadamiro for his occasional check-ins with my progress. I am grateful to my parents, Mr. & Mrs. Dosumu and my siblings for their constant love, support, and prayers to complete my study successfully. I am blessed to be surrounded by wonderful friends such as Mrs. Dorothy Mbuche, Dr. Tamika Garrick, Dr. Teresia Nyoike, Dr. 4 Eutychus Kariuki, Dr. Jerrine Foster, and Ms. Adeola Oyelade for their help, encouragement, advice, and support at various stages of my Ph.D journey. I thank the students and post-doctoral associates at the Small Fruit and Vegetable IPM Laboratory and the staff at the Plant Science and Research Education Unit in Citra for their help with planting, harvesting, and protecting the strawberries during freeze periods, especially Mr. Buck Nelson for always picking my calls and providing me with adequate help when needed. I am grateful to my pastor, Dr. John Cowart of Abiding Faith Christian Church (AFCC) for his prayers, advice, encouragement and mental support. I thank the following church members for their encouragement, prayers, and support; Dr. Marcia Buresch, Dr. Hellena Scott- Okafor, Ms. Theresa Glaeser, Rev. Lydia Knighton, Ms. Patricia Stubbs, Mrs. Bridget Stokes, Mrs. Larose Manker, and Mrs. Constance Taylor. I thank my husband, Mr. Ademola Olaniyi Dada for his help with field work, constant encouragement, patience, and support throughout my program. I acknowledge my son, Jedidiah Olaniyi for fueling the willpower within me to finish strong. As you would say “I did it”, mummy did it and she is proud that she achieved this milestone with you in her life. Thank you for being the bright spot in my life. Above all, I am eternally grateful to God for the strength and grace that made me complete my PhD program, and beyond even as I go further in my career path. 5 TABLE OF CONTENTS page ACKNOWLEDGMENTS ...............................................................................................................4 LIST OF TABLES ...........................................................................................................................9 LIST OF FIGURES .......................................................................................................................10 ABSTRACT ...................................................................................................................................12 CHAPTER 1 INTRODUCTION ..................................................................................................................14 Strawberry Production in Florida ...........................................................................................15 Justification of the Study ........................................................................................................18 Specific Objectives .................................................................................................................20 2 LITERATURE REVIEW .......................................................................................................22 Biology of the Twospotted Spider Mite, Tetranychus urticae Koch......................................22 Webbing ..........................................................................................................................23 Dispersal ..........................................................................................................................24 Diapause ..........................................................................................................................24 Symptoms of Injury and Management of TSSM ............................................................25 Cultural control ........................................................................................................26 Chemical control ......................................................................................................27 Biological control .....................................................................................................28 Predatory Mite, Neoseiulus californicus McGregor ........................................................28 Host Plant Resistance ......................................................................................................29 3 SUSCEPTIBILITY OF SELECTED COMMERCIAL STRAWBERRY CULTIVARS TO TWOSPOTTED SPIDER MITE, TETRANYCHUS URTICAE KOCH IN ORGANIC PRODUCTION ...................................................................................................32 Introduction .............................................................................................................................32 Materials and Methods ...........................................................................................................34 Laboratory and Greenhouse Experiments .......................................................................34 Twospotted spider mite colony ................................................................................34 Population density of twospotted spider mites .........................................................35 Field Trials .......................................................................................................................35 Study site ..................................................................................................................35 Plot layout and experimental design ........................................................................36 Planting .....................................................................................................................37 Sampling ...................................................................................................................38 Marketable yield .......................................................................................................38 6 Data analysis ............................................................................................................39 Results.....................................................................................................................................40 Population Density of Twospotted Spider Mite (TSSM) ................................................40 Greenhouse study .....................................................................................................40 Field trials .................................................................................................................41 Marketable Yield .............................................................................................................43 Discussion ...............................................................................................................................45 Greenhouse Trial .............................................................................................................45 Field Experiments ............................................................................................................45 Marketable Weight ..........................................................................................................47 4 DISPERSAL AND MOVEMENT OF NEOSEIULUS CALIFORNICUS MCGREGOR ......58 Introduction .............................................................................................................................58 Materials and Methods