UNIVERSITY OF CATANIA FACULTY OF AGRICULTURE DEPARTMENT OF AGRI-FOOD AND ENVIRONMENTAL SYSTEMS MANAGEMENT INTERNATIONAL PhD PROGRAMME IN PLANT HEALTH TECHNOLOGIES CYCLE XXIV 2009-2012 Jendoubi Hanene Current status of the scale insect fauna of citrus in Tunisia and biological studies on Parlatoria ziziphi (Lucas) COORDINATOR SUPERVISOR Prof. Carmelo Rapisarda Prof. Agatino Russo CO-SUPERVISOR Dr. Pompeo Suma EXTERNAL SUPERVISORS Prof. Mohamed Habib Dhouibi Prof. Ferran Garcia Marì - 1 - In the name of God, Most Gracious, Most Merciful ِ ِ اقَْرأْ بِا ْسم َربِّ َك الَّذي خَلَق Read! In the name of your Lord Who has created (all that exists). ِ خَلَ َق اْْلِنسَا َن م ْن عَلَ ق He has created man from a clot. اقَْرأْ َوَربُّ َك اْْلَ ْكَرمُ Read! And your Lord is Most Generous, ِ ِ الَّذي عَلَّمَ بِالْق َلَم Who has taught (the writing) by the pen عَلَّمَ اْْلِنسَا َن مَا لَْم يَْعلَم He has taught man what he knew not. صدق اهلل العظيم God the almighty spoke the truth - 2 - Declaration "I hereby declare that this submission is my own work except for quotation and citations which have been duly acknowledged; and that, to the best of my knowledge and belief, it contains no material previously published or written by another person nor material which to a substantial extent has been accepted for the award of any other degree or diploma of the university or other institute of higher learning". Hanene Jendoubi 08.12.2011 - 3 - Title Thesis Current status of the scale insect fauna of citrus in Tunisia and biological studies on Parlatoria ziziphi (Lucas) - 4 - Dedication I dedicate this thesis to my wonderful parents who have continuously told me how proud they are of me. To the memory of my father Mustapha who sacrificed everything to bring me up with love and affection. To my warmth mother Mahbouba; without her support and encouragement before and during my study period and in my entire life, I would never have made it this far. To my sisters and my brothers for the never ending supports that have given me and for always being there. All my love and best wishes - 5 - ACKNOWLEDGMENTS It is with great pleasure that I write these letters in order to express my deep sense of gratitude to Pr. Agatino Russo, for giving me the opportunity to obtain my PhD degree, providing me with an adequate foundation for this thesis. He has given me numerous chances to expand my horizons and for that I am forever grateful. Great and distinct thanks to Dr. Pompeo Suma for his help and guidance; sincere appreciation goes to him for his encouragement and friendly approach. My gratitude to Pr. Ferran Garcia Mari, whom I give all my respect, for his experienced advice and scientific endless support during all my training period at the Agroforestal Mediterranean Institute, Polytechnic University of Valencia. My distinct thanks and sincere respect to Prof. Dhouibi Mohamed Habib for accepting me during survey period in the laboratory of entomology at the National Agronomic Institute of Tunisia. Ms. Marehbene Jamel director of crop protection service in Nabeul and Ms. Bou Jemaa, director of crop protection service in the Northwest region deserve special thanks for the continuous help and great support during all the field surveys conducted in Tunisia. I acknowledge gratefully the committee of jury for accepting to evaluate the work and the PhD coordinator Pr. Rapisarda C. for all his care in managing very well the PhD programm. I want to thank all my lab partners for helping me with my research. Special thanks to Dr. La Pergola A. and Dr. Zappala L. for identifying ants and parasits found during my work. Finally, I would like to acknowledge the whole Department of Agri-food and Environmental Systems Management at the University of Catania for their kindness and good-natured attitude; I could not have picked a better department to attend. Special thanks to Prs. Siscaro G., Mazzeo G., Longo S., Barbagallo S., Coccuzza G. and the most kind Dr. S. Bella. Finally, I would like to thank all the PhD students and my friends (Ahmed, Antonio, Claudia, Daniel, Khaleed, Sara, and my dear Yosra) for the merry atmosphere and all the pleasant moments we shared together; all the success. Hanan. - 6 - Approval SCALES Scales are soft and scales are hard. They are in the orchard and in the yard. The soft ones are attached to their outer skin, While the hard ones live free within. Soft scales produce honeydew, But hard scales find it impossible to do. It's just as well it works that way- Legless, the hard ones can't move away. By Albert A. Grigarick - 7 - TABLE OF CONTENTS Declaration……………………………………………………………………………………………………………………………………………..…………………3 Title thesis…………………………………………………………………………………………………………….………………………………..…………………4 Dedication……………………………………………………..………………………………………………………………………………………………..………..5 Acknowledgment……………………………………………..………………………………………………………………………………………..……………..6 Aproval………………………………………………………………………………………………………………………………………………………………………7 Table of contents…………………...…………………….……………………….......................................................................................8 Abstracts………………………………………………………………………………………………………………………………………………………………….11 List of tables………………………………………………...………………………………………………………………………………………………………….13 List of figures………………………………………………..…………………...........................................................................................15 INTRODUCTION………………………………………………………………..…………………………………………………………………………………………. - 16 - CHAPTER 1. LITERATURE REVIEW…….…………………………..…………………………................................................................... - 19 - I. Importance of citrus crop -------------------------------------------------------------------------------------------------------------- - 19 - I.1. Historic ------------------------------------------------------------------------------------------------------------------------------------ - 19 - I.2. Production -------------------------------------------------------------------------------------------------------------------------------- - 19 - I.3. Exports-Imports ------------------------------------------------------------------------------------------------------------------------- - 20 - I.4. Citrus production in Tunisia --------------------------------------------------------------------------------------------------------- - 21 - II. Coccoid pests of citrus ----------------------------------------------------------------------------------------------------------------- - 22 - II.1. Classification ---------------------------------------------------------------------------------------------------------------------------- - 22 - II.2. Morphology ----------------------------------------------------------------------------------------------------------------------------- - 23 - II.3. Biology and life history --------------------------------------------------------------------------------------------------------------- - 25 - II.4. Ecology and dispersal ----------------------------------------------------------------------------------------------------------------- - 26 - III. Pest status of citrus scale insects -------------------------------------------------------------------------------------------------- - 28 - III.1. Economic importance and damages --------------------------------------------------------------------------------------------- - 28 - III.2. Control ----------------------------------------------------------------------------------------------------------------------------------- - 29 - III.3. Major species pests in Mediterranean Basin ---------------------------------------------------------------------------------- - 31 - III.3.1. Recognition of main pest citrus families ------------------------------------------------------------------------------------- - 31 - III.3.2. List of main species ---------------------------------------------------------------------------------------------------------------- - 33 - IV. Scale insect species of citrus in Tunisia ------------------------------------------------------------------------------------------ - 33 - IV.1. Species newly recorded on citrus ------------------------------------------------------------------------------------------------ - 34 - IV.1.1. Ceroplastes floridensis Comstock 1881 -------------------------------------------------------------------------------------- - 34 - IV.1.2. Chrysomphalus pinnulifer (Maskell, 1891) ---------------------------------------------------------------------------------- - 36 - IV.1.3. Coccus pseudomagnoliarum (Kuwana, 1914) ------------------------------------------------------------------------------ - 37 - IV.2. Species of economic importance ------------------------------------------------------------------------------------------------- - 39 - IV.2.1. Parlatoria pergandii Comstock 1881 ----------------------------------------------------------------------------------------- - 39 - IV.2.2. Parlatoria ziziphi (Lucas, 1853) ------------------------------------------------------------------------------------------------- - 42 - IV.2.3. Planococcus citri (Risso, 1813) -------------------------------------------------------------------------------------------------- - 44 - IV.2.4. Icerya purchasi Maskell 1879 --------------------------------------------------------------------------------------------------- - 47 - IV.2.5. Chrysomphalus dictyospermi (Morgan, 1889) ------------------------------------------------------------------------------ - 48 - IV.2.6. Lepidosaphes beckii (Newman, 1869) ----------------------------------------------------------------------------------------