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University of Alberta University of Alberta Seasonal phenology and reproductive behaviour of Dioryctria species Zeller (Lepidoptera: Pyralidae) in British Columbian seed orchards by Caroline Marie Whitehouse A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Ecology Department of Biological Sciences ©Caroline M. Whitehouse Spring 2011 Edmonton, Alberta Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission. Library and Archives Bibliothèque et Canada Archives Canada Published Heritage Direction du Branch Patrimoine de l’édition 395 Wellington Street 395, rue Wellington Ottawa ON K1A 0N4 Ottawa ON K1A 0N4 Canada Canada Your file Votre référence ISBN: 978-0-494-70885-9 Our file Notre référence ISBN: 978-0-494-70885-9 NOTICE: AVIS: The author has granted a non- L’auteur a accordé une licence non exclusive exclusive license allowing Library and permettant à la Bibliothèque et Archives Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par télécommunication ou par l’Internet, prêter, telecommunication or on the Internet, distribuer et vendre des thèses partout dans le loan, distribute and sell theses monde, à des fins commerciales ou autres, sur worldwide, for commercial or non- support microforme, papier, électronique et/ou commercial purposes, in microform, autres formats. paper, electronic and/or any other formats. The author retains copyright L’auteur conserve la propriété du droit d’auteur ownership and moral rights in this et des droits moraux qui protège cette thèse. Ni thesis. Neither the thesis nor la thèse ni des extraits substantiels de celle-ci substantial extracts from it may be ne doivent être imprimés ou autrement printed or otherwise reproduced reproduits sans son autorisation. without the author’s permission. In compliance with the Canadian Conformément à la loi canadienne sur la Privacy Act some supporting forms protection de la vie privée, quelques may have been removed from this formulaires secondaires ont été enlevés de thesis. cette thèse. While these forms may be included Bien que ces formulaires aient inclus dans in the document page count, their la pagination, il n’y aura aucun contenu removal does not represent any loss manquant. of content from the thesis. Dedication This thesis is dedicated to my parents, Lloyd and Dianne. As a child, you inspired my passion and curiosity for the natural world. As an adult, you provided me with the unconditional love and support to continue exploring that world. Thank you. Abstract Seasonal phenology and mating frequency of moths in the genus Dioryctria found sympatrically in north Okanagan Valley, British Columbia seed orchards were assessed. Female moths in the abietella, auranticella, ponderosae and schuetzeella species groups were trapped in Douglas-fir, lodgepole pine and interior spruce stands. Most species were univoltine based on one peak of flight activity per season. There is evidence that the abietella group are bivoltine in this region. Females in the abietella and auranticella groups are polyandrous; ponderosae and schuetzeella females are monandrous. The sole abietella species, D. abietivorella, recorded in British Columbia can have substantial economic impacts on seed production in commercial seed orchards. Factors influencing reproductive behaviour, longevity and fecundity of D. abietivorella were investigated. Females are synovigenic and have an income-breeding mating strategy. Reproductive behaviours are delayed post-eclosion and signalling receptivity by females coincides with egg maturation, increasing with age. Female D. abietivorella experience trade-offs between reproduction and longevity. Acknowledgements Many people were integral to the success of my project. I would like to thank Dr. Maya Evenden, my supervisor, for the opportunity to conduct science and for the guidance on how to think critically about science, including the importance of “failed” experiments. She is a role model for women in science as an example of a successful woman balancing the demands of a academic career with that of her family. Thank you to my committee members, Drs. Nadir Erbilgin, Felix Sperling and Ward Strong, who provided time, support, and positive critiques which helped to shape my research. Thank you to Dr. David Coltman for serving as my defense chair. This project could not have occurred without the funding provided by the Forest Genetics Research Council of British Columbia and the University of Alberta. My helpful and witty colleagues at the Kalamalka Forestry Centre made my three field seasons in Vernon, BC productive and exceptionally enjoyable. Anna McIndoe, Natalka Melnyky, Faye Klassen, Torie Lewis, Hwyn Fletcher, and Kyle Artym keenly provided field and lab assistance. They were always ready to do my bidding, even when that included picking thousands of Douglas-fir cones or wandering around orchards at various times of day and night staring a small black and grey moths. I am very grateful to my family, good friends, and even Cyrus who supported me in so many ways (including dog-sitting, trips to warm climates, nightly walks and many forms of stress control). My fellow Evenden lab mates and entomologically-inclined graduate students, particularly Julian Rowe Dupuis, Amanda van Haga, Boyd Mori, Lisa Lumley, Marla Schwartzfeld, and Jason Dombroskie, provided friendship, opportunities to procrastinate (especially on stoops and sunny patios) along with some mighty fine comedy; thank you. Table of contents Chapter 1: The biology and management of North American cone-feeding Dioryctria species ..................................................................................................................................1 Introduction ....................................................................................................................1 Systematics, taxonomy, and diversity of Dioryctria ....................................................2 Cone-feeding Dioryctria .............................................................................................3 General biology ..............................................................................................................8 Seasonal and diurnal phenology ...............................................................................9 Reproductive biology ...............................................................................................14 Host Use: semiochemicals and larval feeding ........................................................17 Evolutionary ecology ...................................................................................................20 Fluctuating abundance of food resources ..............................................................20 Sympatry and interspecific competition ................................................................20 Pest status and management .......................................................................................22 Impacts in natural forest stands .............................................................................22 Impacts in conifer seed orchards ............................................................................23 Monitoring ................................................................................................................25 Decision-making .......................................................................................................27 Control ......................................................................................................................28 Future directions ..........................................................................................................33 Literature cited .............................................................................................................34 Chapter 2: Seasonal flight and mating status of Dioryctria species.............................61 Introduction ..................................................................................................................61 Methods and Materials ................................................................................................65 Statistical analyses .......................................................................................................66 2.1. Seasonal flight phenology of Dioryctria species ................................................67 2.2. Mating status of Dioryctria species females .......................................................68 Results ...........................................................................................................................69 2.1. Seasonal flight phenology of Dioryctria species ................................................69 2.2. Mating status
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