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Intraguild Interactions Between Two Natural Enemies Of INTRAGUILD INTERACTIONS BETWEEN TWO NATURAL ENEMIES OF TRL4LEURODES VAPORARIORUM (HOMOPTERA: ALEYRODIDAE), THE PREDATOR, DICYPHUS HESPERUS (HETEROPTERA: MIRIDAE), AND THE ENTOMOPATHOGENIC FUNGUS, PAECILOMYCES FUMOSOROSEUS APOPKA-97 (DEUTEROMYCOTINA: HYPHOMYCETES) (PFR-9FM) Colleen Rosanne Alma Bachelor of Science in Agriculture, University of Guelph, 2002 THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE In the Department of Biological Sciences O Colleen Rosanne Alma 2005 SIMON FRASER UNIVERSITY Spring 2005 All rights reserved. This work may not be reproduced in whole or in part, by photocopy or other means, without permission of the author. APPROVAL Name: Colleen Rosanne Alma Degree: Master of Science Title of Thesis: Intraguild interactions between two natural enemies of Trialeur des vaporariorum 8et;eroe (Homoptera:Aleyrodidae), the predator, Dicyphus hesperus (%mptera:Miridae), and the entomopathogenic fungus, Paecilomycesjkmosoroseus Apopka-97 (Deuteromycotina: Hyphomycetes) (PFR-97 TM ) Examining Committee: Chair: Dr. J. Mattsson, Assistant Professor Dr. B.D. Roitberg, Professor Department of Biological Sciences, S.F.U. Dr. M.S. Goettel, Research Scientist Agriculture and Agri-Food Canada and Adjunct Professor Department of Biological Sciences, S.F.U. Dr. D.R. Gillespie, Research Scientist Agriculture and Agri-Food Canada and Adjunct Professor Department of Biological Sciences, S.F.U. Dr. Z.K. Punja, Professor Department of Biological Sciences, S.F.U. Dr. D.A. Raworth, Research Scientist PAFRC, Agriculture and Agri-Food Canada Public Examiner Date Approved .. 11 SIMON FRASER UNIVERSITY PARTIAL COPYRIGHT LICENCE The author, whose copyright is declared on the title page of this work, has granted to Simon Fraser University the right to lend this thesis, project or extended essay to users of the Simon Fraser University Library, and to make partial or single copies only for such users or in response to a request from the library of any other university, or other educational institution, on its own behalf or for one of its users. The author has further granted permission to Simon Fraser University to keep or make a digital copy for use in its circulating collection. The author has further agreed that permission for multiple copying of this work for scholarly purposes may be granted by either the author or the Dean of Graduate Studies. It is understood that copying or publication of this work for financial gain shall not be allowed without the author's written permission. Permission for public performance, or limited permission for private scholarly use, of any multimedia materials forming part of this work, may have been granted by the author. This information may be found on the separately catalogued multimedia material and in the signed Partial Copyright Licence. The original Partial Copyright Licence attesting to these terms, and signed by this author, may be found in the original bound copy of this work, retained in the Simon Fraser University Archive. W. A. C. Bennett Library Simon Fraser University Burnaby, BC, Canada ABSTRACT My focus was to investigate the intraguild interactions between two natural enemies of the greenhouse whitefly: Dicyphus hesperus, and Paecilomyces fumosoroseus Apopka-97 (PFR-97TM).PFR-97TM spray applications made to whitefly nymphs resulted in a LCsoof 1.33 x lo5blastospores/ml. Lethal time estimates of whitefly nymphs decreased with increasing concentration of the PFR-97TM spray application. When D. hesperus females were exposed to leaf discs treated with PFR-97TMat a concentration of 100 x LCso of whitefly nymphs, 38% of the females died. The surviving females experienced a 38% feeding reduction. Adult D. hesperus females were able to discriminate between healthy and PFR-97TM-treatedwhitefly nymphs when the nymphs were offered to them five days after spray application. The simultaneous use of D. hesperus and PFR-97TM in tomato greenhouse microcosms resulted in additive whitefly mortality; together they reduced whitefly densities by 62% relative to the control plants in six weeks. iii ACKNOWLEDGEMENTS Foremost, I would like to thank my supervisory committee, Bernard Roitberg, Mark Goettel, David Gillespie and Zamir Punja, for their guidance and assistance during the past two years. This work was supported by NSERC, Biocontrol Network, Agriculture and Agri-Food Canada (AAFC), and the British Columbia Greenhouse Research Council. The commercial formulation PFR-97TMwas kindly provided by Certis USA, Columbia MD. Plants were grown and maintained by Mark Gross (Pacific Agri- Food and Research Center, Agassiz). I acknowledge Ian Bercovitz for his assistance with the statistical analyses of the greenhouse trial. I am grateful to William deVane for his willingness to assist me with inquiries related to PFR-97'M and to Dr. Russell Nicholson for the use of his electrobalance. I would like to express my gratitude to Grant Duke for his guidance and assistance during the preparation and execution of the bioassays. I am very grateful to Angela Mah and Jasmin Gee for their assistance with the collection of experimental data. Lastly, I would like to thank my husband, Randy, for lending a hand whenever it was needed, my sister, Carolyn, and the rest of my family for their support during the last two years. TABLE OF CONTENTS .. Approval.......................................................................................................................... II ... Abstract ............................................................................................................................111 Acknowledgements .........................................................................................................iv Table of Contents ..............................................................................................................v .. List of Figures ..................................................................................................................vn List of Tables .................................................................................................................... ix Chapter 1 Introduction .................................................................................................. 1 1.1 Abstract ........................................................................................................... 1 1.2 Literature Review ........................................................................................... 2 1.2.1 Trialeurodes vaporariorum ............................................................................ 2 1.2.2 Natural Enemies of Trialeurodes vaporariorum ............................................ 5 1.2.3 Dicyphus hesperus ........................................................................................ 10 1.2.4 Paeci2omyces fumosoroseus ......................................................................... 13 1.2.5 Interaction between Natural Enemies ........................................................... 17 1.3 Research Objectives ..................................................................................... 20 1.4 References .................................................................................................... 21 Chapter 2 Pathogenicity of PFR-97FM against Trialeurodes vaporariorum ............ 33 2.1 Abstract ......................................................................................................... 33 2.2 Introduction .................................................................................................. 34 2.3 Materials and Methods ................................................................................. 36 2.3.1 Insect Cultures and Host Plants .................................................................... 36 2.3.2 Fungal Preparations ...................................................................................... 37 2.3.3 Bioassay Protocol ......................................................................................... 38 2.3.4 Sampling Protocol ........................................................................................ 39 2.3.5 Statistical Analysis ....................................................................................... 40 2.4 Results .......................................................................................................... 41 2.5 Discussion.................................................................................................... 43 2.6 Figures .......................................................................................................... 47 Tables........................................................................................................... 53 References .................................................................................................... 57 Chapter 3 Influence of PFR-97FM on Dicyphus hesperus .........................................60 3.1 Abstract ......................................................................................................... 60 3.2 Introduction .................................................................................................. 61 3.3 Materials and Methods ................................................................................. 63 3.3.1 Insect Cultures and Host Plants .................................................................... 63 3.3.2 Fungal Preparations .....................................................................................
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