Ecology and Integrated Pest Management of the Carrot Rust Fly (Psila rosae (Fabricius, 1794)), in the Holland Marsh, Ontario by Jason Lemay A Thesis presented to The University of Guelph In partial fulfilment of requirements for the degree of Master of Science in Plant Agriculture Guelph, Ontario, Canada © Jason Lemay, December, 2016 ABSTRACT Ecology and Integrated Pest Management of the Carrot Rust Fly (Psila rosae (Fabricius, 1794)), in the Holland Marsh, Ontario Jason Paul Lemay Advisors: University of Guelph, 2016 Professor M.R. McDonald Professor C. Scott-Dupree This thesis is an investigation of the ecobiology and integrated pest management (IPM) of the carrot rust fly (Psila rosae) (CRF) in the Holland Marsh, Ontario. The Holland Marsh is a major carrot producing area in North America. Carrot rust fly is a serious pest of carrots. An IPM program for CRF is used within the Holland Marsh. Published CRF rearing procedures were found to be inadequately detailed. Improvements to the procedure were identified. Various insecticides, including seed treatments, in-furrow, and post- emergent, were evaluated for their effectiveness to control CRF. No conclusions could be made on their effectiveness due to low pest pressure. The natural enemy species composition in the Holland Marsh was determined and known CRF and carrot weevil natural enemies were identified. The IPM program used in the Holland Marsh was not found to be detrimental to the natural enemy species richness or abundance. iii ACKNOWLEDGEMENTS I would like to thank my advisors, Drs. Mary Ruth McDonald and Cynthia Scott-Dupree for their continued assistance during this project, for challenging me to continue when things were not going well. I would also like to thank my advisory committee member, Dr. Stephen Marshall for his guidance and assistance, especially for help identifying natural enemies of carrot rust fly and providing me with the incredible photographs of carrot rust fly and associated natural enemies. To Dr. Guy Boivin of Agriculture and Agri-Food Canada, and his research assistant, Julie Frenette, I cannot thank you enough for generously sending me carrot rust fly larvae, twice. I would like to thank Dr. Alan Taylor of Cornell University, for preparing the insecticidal seed treatments used during this research. For the invaluable assistance maintaining our many research plots over the past two summers, as well as all their technical support, I would like to thank Kevin Vander Kooi, Dennis Van Dyke, Laura Riches, Shawn Janse, and the rest of the Muck Crop Research Station staff. A special thanks to Zach Telfer, who I worked closely with the past two years on everything from managing field trials to sharing committee meetings. To my lab mates Andrew McLean and Selasi Tayviah, thank you for your help with statistics, and always being there to talk. To Dr. Fadi Al-Daoud, for taking your time to show me DNA extraction and PCR techniques, and for always listening to me tell you why the Leafs suck, or why the Blue Jays won’t re-sign Bautista. As well as to the rest of the McDonald and Scott- Dupree labs, you were all great to work with, and have made the last two years enjoyable. And finally, to my girlfriend, Andrea, and my family, thank you for listening to me complain incessantly over the past two years when my research was a burden, and always being the pillar of support I needed to not quit this project. I know I would not be here without you. iv TABLE OF CONTENTS ACKNOWLEDGEMENTS ........................................................................................................... iii TABLE OF CONTENTS ............................................................................................................... iv LIST OF TABLES ........................................................................................................................ vii LIST OF FIGURES, ILLUSTRATIONS, PLATES...................................................................... ix LIST OF SYMBOLS, ABBREVIATIONS, OR NOMENCLATURE ......................................... xi Chapter 1 Literature Review ........................................................................................................... 1 1.1 Introduction ...................................................................................................................... 1 1.2 Biology and Behaviour..................................................................................................... 2 1.3 Life Cycle and Development............................................................................................ 3 1.3.1 Egg: ........................................................................................................................... 6 1.3.2 Larva: ........................................................................................................................ 6 1.3.3 Pupa: ......................................................................................................................... 8 1.3.4 Adult: ........................................................................................................................ 9 1.4 Distribution and Pest Status ........................................................................................... 10 1.5 Integrated Pest Management .......................................................................................... 11 1.5.1 Monitoring and Thresholds ..................................................................................... 13 1.5.2 Forecasting models ................................................................................................. 14 1.5.3 Genetic Control ....................................................................................................... 14 1.5.4 Cultural Control ...................................................................................................... 16 1.5.5 Physical Control ...................................................................................................... 18 1.5.6 Biological Control ................................................................................................... 18 1.5.7 Biopesticide Control ............................................................................................... 20 1.5.8 Chemical Control .................................................................................................... 20 1.6 Research Objectives ....................................................................................................... 22 Chapter 2 Weather – Carrot Rust Fly Relationship ................................................................. 25 2.1 Introduction: ................................................................................................................... 25 2.2 Methods: ......................................................................................................................... 26 2.3 Results: ........................................................................................................................... 27 2.4 Discussion: ..................................................................................................................... 31 Chapter 3 Chemical Control of Carrot Rust Fly ...................................................................... 37 v 3.1 Introduction: ................................................................................................................... 37 3.2 Methods: ......................................................................................................................... 40 3.2.1 Experimental design: .............................................................................................. 40 3.2.2 Insecticide treatments: ............................................................................................ 43 3.2.3 Harvest and Assessment: ........................................................................................ 52 3.2.4 Statistical analysis: .................................................................................................. 53 3.3 Results: ........................................................................................................................... 53 3.3.1 IPM program evaluation: ........................................................................................ 55 3.3.2 Seed treatment:........................................................................................................ 56 3.3.3 In-furrow application: ............................................................................................. 57 3.3.4 Post-emergent Application: .................................................................................... 57 3.3.5 Synergist Application: ............................................................................................ 58 3.3.6 Planting Date:.......................................................................................................... 58 3.4 Discussion: ..................................................................................................................... 59 3.5 Conclusion:..................................................................................................................... 64 Chapter 4 Survey for Ground-Dwelling Natural Enemies of Carrot Rust Fly ........................ 66 4.1 Introduction: ................................................................................................................... 66 4.2 Methods: ........................................................................................................................