Edith Cowan University Research Online Theses: Doctorates and Masters Theses 2018 Seed morphology, dormancy and germination of South-West Australian Ericaceae Michael Just Edith Cowan University Follow this and additional works at: https://ro.ecu.edu.au/theses Part of the Biology Commons Recommended Citation Just, M. (2018). Seed morphology, dormancy and germination of South-West Australian Ericaceae. https://ro.ecu.edu.au/theses/2051 This Thesis is posted at Research Online. https://ro.ecu.edu.au/theses/2051 Edith Cowan University Copyright Warning You may print or download ONE copy of this document for the purpose of your own research or study. The University does not authorize you to copy, communicate or otherwise make available electronically to any other person any copyright material contained on this site. You are reminded of the following: Copyright owners are entitled to take legal action against persons who infringe their copyright. A reproduction of material that is protected by copyright may be a copyright infringement. Where the reproduction of such material is done without attribution of authorship, with false attribution of authorship or the authorship is treated in a derogatory manner, this may be a breach of the author’s moral rights contained in Part IX of the Copyright Act 1968 (Cth). Courts have the power to impose a wide range of civil and criminal sanctions for infringement of copyright, infringement of moral rights and other offences under the Copyright Act 1968 (Cth). Higher penalties may apply, and higher damages may be awarded, for offences and infringements involving the conversion of material into digital or electronic form. Seed morphology, dormancy and germination of South-West Australian Ericaceae This thesis is presented in fulfilment to the requirements for the Degree of Master of Biological Science Michael Just Edith Cowan University School of Science 2018 Abstract The Ericaceae in South West Australia contains species with difficult to germinate seeds, including many species with deep intractable dormancy. A better understanding of seed biology and species specific dormancy, and germination mechanisms is required to overcome these difficulties. Land clearing, salinity and disease has resulted in over 125 species within 15 genera being listed as rare, highly restricted, threatened and endangered (Western Australian Herbarium 1998–). The present study examined the seed biology of eight species of Ericaceae native to Western Australia, exploring fruit and seed morphology, dormancy and germination. Cold and warm stratification was used in combination with gibberellic acid to classify dormancy. Among the two distinct fruit types that occur within the Ericaceae separate patterns of dormancy were found. Seeds held within a dehiscent capsule were found to possess non-deep and intermediate physiological dormancy whilst those within an indehiscent drupe possessed physiological and morphophysiological dormancy. Oxygen and nitric oxide enriched atmospheres, removal of seeds from endocarps and propagation from cuttings provided potential avenues for the propagation of study species. i Acknowledgments My sincerest gratitude to everyone that took part in this project. Thank you to the Wildflower Society of Western Australia’s Northern Suburbs branch for funding the project and for the continued and unwavering support throughout. To my supervisors, a thousand times thank you. Will and Katherine your feedback and advice was invaluable. Kristina, this project could not have happened without you. Whether finding specimens to collect from, or reigning in my writing, you were there every step of the way and it truly means the world. To my fiancé Chloe, thank you for always being there. I would not have gotten here without you. My apologies for dragging you into the field at every opportunity. I would like to acknowledge the Biodiversity Conservation Centre, Kings Park for allowing me to access their x-ray machines. A big thankyou to Brian Heterick at the Museum of Western Australia for his help and advice in identifying the wasp species that were eating all my seeds. Thank you to the Department of Biodiversity, Conservation and Attractions for issuing collection licences and granting access to their managed reserves. Finally, thank you to all those who responded to emails over the course of the project, answering the questions I had posed and directing me to further sources of information. It was a pleasure to see so many high level academics taking the time to respond to someone just starting out. Declaration I certify that this thesis does not, to the best of my knowledge and belief: i. Incorporate without acknowledgment any material previously submitted for a degree or diploma in any institution of higher education; ii. Contain any material previously published or written by another person except where due reference is made in the text of this thesis; or iii. Contain any defamatory material ii Table of Contents Abstract ............................................................................................................................. i Acknowledgments ........................................................................................................... ii Declaration ....................................................................................................................... ii Table of Contents ........................................................................................................... iii List of Tables ................................................................................................................... v List of Figures ................................................................................................................. vi Chapter 1 Introduction and literature review 1.1 Introduction ............................................................................................................. 1 1.2 Germination response and dormancy types within Ericaceae ............................... 10 1.3 Australian Ericaceae .............................................................................................. 11 1.4 Aims ...................................................................................................................... 16 Chapter 2 General methods ......................................................................................... 18 2.1 Introduction ........................................................................................................... 18 2.2 Species selection and collection sites .................................................................... 18 2.3 Collection and processing...................................................................................... 20 2.4 Sterilization ........................................................................................................... 20 2.5 Germination tests ................................................................................................... 20 Chapter 3 Fruit, seed and embryo morphology of eight Ericaceae from South- West Australia: implications for viability, dormancy and germination 3.1 Introduction ........................................................................................................... 21 3.2. Methods ................................................................................................................ 23 3.3. Results .................................................................................................................. 27 3.4 Discussion ............................................................................................................. 44 3.5 Conclusions ........................................................................................................... 48 Chapter 4 Dormancy class and germination in eight species of South-West Australian Ericaceae 4.1 Introduction ........................................................................................................... 50 4.2 Methods ................................................................................................................. 53 iii 4.3 Results ................................................................................................................... 58 4.4 Discussion ............................................................................................................. 62 4.5 Conclusions ........................................................................................................... 66 Chapter 5 Techniques for the rapid propagation of intractable South-West Australian Ericaceae 5.1 Introduction ........................................................................................................... 68 5.2 Methods ................................................................................................................. 69 5.3 Results ................................................................................................................... 74 5.4 Discussion ............................................................................................................. 80 5.5 Conclusions ........................................................................................................... 83 Chapter 6 Conclusions.................................................................................................. 85 References ...................................................................................................................... 92 Appendix