View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Cape Peninsula University of Technology IN-VITRO PROPAGATION STUDIES OF THE ENDANGERED SUCCULENTS DROSANTHEMUM MICANS AND DROSANTHEMUM HALLII (AIZOACEAE) by ASANDA MLUNGWANA Thesis submitted in fulfillment of the requirements for the degree Master of Horticultural Science in the Faculty of Applied Sciences at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY Supervisor: Prof L Kambizi Co-supervisor: Dr I Matimati Bellville April 2018 CPUT copyright information The dissertation/thesis may not be published either in part (in scholarly, scientific or technical journals), or as a whole (as a monograph), unless permission has been obtained from the University. DECLARATION I, Asanda Mlungwana, declare that the contents of this dissertation/thesis represent my own unaided work, and that the dissertation/thesis has not previously been submitted for academic examination towards any qualification. Furthermore, it represents my own opinions and not necessarily those of the Cape Peninsula University of Technology. Signed Date i DEDICATION I dedicated this work to my mother Nompendulo Elda Mlungwana and my late father Siphumo Robert Mlungwana. Lala ngoxolo Mzondi, uyawuhlala uphakathi kwentliziyo zethu. ii ACKNOWLEDGMENT I would like to thank God for His guidance, constant love and blessings. Not forgetting my ancestors’ ooMyirha, Mzondi, Sampu, Ziyeka (Ithambo lenyoka lihlaba elimzondayo) for protection and love. A special thanks to Prof. Kambizi for his guidance, strength, valuable criticism, encouragement and advice. My sincere gratitude to Dr. Matimati, for his constant perseverance, supervision, support, sharing his knowledge and research expertise throughout this study. It was an honor and privilege working with you. I also wish to thank my mother Nompendulo Elda Mlungwana for her prayers, love and comfort when things get tough. I am the woman I am today ngenxayakho Marhadebe. My sister Zukiswa Mlungwana, my bothers Kholwani Mlungwana, Ntsikelelo Mlungwana and Banele Mlungwana. I would like to acknowledge the support and love of my friends and colleagues Sibusiso Xego, Pumla Staffa, Yonela Vakele, Axola Qongqo, and Mbulelo Ofisi. The Horticultural Science Department technicians Mvuyisi Mtshisazwe, Phumlani Roto, Terrance Hlokane Mabela and Deborah Erasmus for their assistance in ensuring that my experiment needs were met. Not forgetting the CPUT senior librarian Mrs Vuyokazi Kiva-Johnson for her wisdom. Lastly I would like to express my gratitude to the Karoo Botanical garden (SANBI), specifically Ricardo Riddles and Deon Viljoen for ensuring that I had enough plant material for my experiment. The financial assistance of the National Research Foundation towards this research is acknowledged. Opinions expressed in this thesis and the conclusions arrived at, are those of the author, and are not necessarily to be attributed to the National Research Foundation. iii CONTENTS DECLARATION ................................................................................................................ i DEDICATION ...................................................................................................................ii ACKNOWLEDGMENT .................................................................................................... iii CONTENTS ....................................................................................................................iv LIST OF TABLES ........................................................................................................... vii ABSTRACT .................................................................................................................... xii CHAPTER 1 .................................................................................................................... 1 Introduction, background to the research problem .......................................................... 1 1.1 General introduction ........................................................................................... 1 1.1.1 Statement of the research problem ............................................................. 1 1.1.2 Background of the study .............................................................................. 1 1.2 Objectives of the study ....................................................................................... 3 1.3 References ......................................................................................................... 4 CHAPTER 2 .................................................................................................................... 6 Is in-vitro propagation of endangered Drosanthemum species endemic to the Succulent Karoo possible? .............................................................................................................. 6 2.1 Introduction ........................................................................................................ 6 2.2 Succulent plants and their importance in South Africa ....................................... 7 2.3 Diversity of the Aizoaceae family ....................................................................... 9 2.4 Drosanthemum species ................................................................................... 10 2.5 Taxonomy and conservation of the Aizoaceae family ...................................... 11 2.6 Cryopreservation of endangered Aizoaceae species ....................................... 14 2.7 In-vitro propagation of Aizoaceae plants .......................................................... 15 iv 2.8 Growth regulators for in vitro propagation of Aizoaceae .................................. 17 2.8.1 6-Benzyladenine (BA), 2-isopentenyladenine (2iP), kinetin and thidiazuron (TDZ) as shoot inducing hormones ........................................................................ 18 2.8.2 Indole-3-acetic acid (IAA) and naphthalene acetic acid as root induction phytohormones ...................................................................................................... 18 2.9 Conclusion ....................................................................................................... 18 2.10 References ................................................................................................... 19 CHAPTER 3 .................................................................................................................. 31 In-vitro propagation studies of the endangered succulent Drosanthemum hallii (Aizoaceae) ................................................................................................................... 31 3.1 Introduction ...................................................................................................... 31 3.2 Materials and methods ..................................................................................... 32 3.2.1 Explant source ........................................................................................... 32 3.2.2 Sterilization method ................................................................................... 33 3.2.3 Culture medium and conditions ................................................................. 33 3.2.4 Acclimatization ........................................................................................... 33 3.2.5 Data collection and statistical analysis ...................................................... 34 3.3 Results ............................................................................................................. 34 3.3.1 Callus induction in D. hallii ......................................................................... 34 3.3.2 Shoot formation of D. hallii ......................................................................... 37 3.3.3 Browning of D. hallii ................................................................................... 40 3.3.4 Rooting of D. hallii ..................................................................................... 43 v 3.3.5 Acclimatization of D. hallii .......................................................................... 45 3.4 Discussion and conclusion ............................................................................... 45 3.5 References ....................................................................................................... 48 CHAPTER 4 .................................................................................................................. 53 Micropropagation studies of an endemic and endangered succulent Drosanthemum micans (Aizoaceae) ....................................................................................................... 53 4.1 Introduction ...................................................................................................... 53 4.2 Materials and methods ..................................................................................... 53 4.2.1 Sourcing of explant .................................................................................... 53 4.2.2 Sterilization ................................................................................................ 54 4.2.3 Culture medium and conditions ................................................................. 54 4.2.4 Observation of cultures and statistical analysis ......................................... 54 4.3 Results ............................................................................................................. 55 4.3.1 Shoot