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University of Southampton Research Repository ePrints Soton Copyright © and Moral Rights for this thesis are retained by the author and/or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This thesis cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder/s. The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders. When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given e.g. AUTHOR (year of submission) "Full thesis title", University of Southampton, name of the University School or Department, PhD Thesis, pagination http://eprints.soton.ac.uk UNIVERSITY OF SOOTHMCPTC®! OHE INTER AND INTRA-G^ERIC RELATIONSHIPS BKWEEN PSOPrnX^RPUS SPB. AND TOEIR AIJLIES A Thesis submitted for the Degree of Master of Philosophy in the University of Southaagyton by Nigel Maxted Department of Biology July 1984 I would lx}c6 to dGdicate this tTissis to tlis msinoiry of a. specxa.1 friend, Alan Graves FLEOR Si je livrois mon imaginatiion aux douces sensations que ce root semble appeller, je pourrois faire un article agr^able peutetre aux Bergers, mais fort mauvais pour les Botanistes. Ecartons done un moment les vives couleurs, les odeurs suaves, les formes elegantes, pour chercher premierentent a bien connoitre I'etre organise qui les rassemble. Jean-Jacques Rousseau (Dictionnaire de Botanique) (i) ACKNOWLEDGEMENTS I am particularly grateful to the following: Dr. P. Biavandiar. N. _ A* supanislM, enomnrageme^amd stimulating diacussion. Dr. Haq for allowing me to undertake a part-time project while working for him. Dr. B, Verdcourt - for originally suggesting the project and thus providing me with three years enj oyment. For encouragement and discussion throughout the course of the investigation. Dr. R.M. Polhill - for encouragement, advice and discussion of the project. Mr. G. Lewis, Mr. C. Stirton, and Ms. s. Andrews - for help and making my work in the herbarium at R.B.G. (Kew) so enjoyable. Dr. R. Marechal - for encouragement, advice and discussion of the project. Dr. R. White and Dr. R. Allkin - for discussion and advice on the numerical methods. Mr. R. cornick - for assistance in drawing the figures. Mr. B. Lockyer - for assistance with the photographic work. Mks K. Klfby _ for typing the thesis and Mrs s. Hall and Mts S. GGrside for its materialisation. The Staff of the Department of the Biology, Southampton - for help in numerous ways throughout the project. My thanks are also due to the curators of the Herbaria from whom the specimens, detailed in Appendix 8, were loaned. Finally, i would like to thank, Jaquie, Judith and Joe for being there, and not there, when I needed them. (ii) ABSTRACT FACULTY OP SCIENCE BIOLOGY Master of Philosophy THE INTER AND INTRA-GENERIC RELATIONSHIPS BETWEEN PSOPHOCARPUS SPP. AND IHEIR ALLIES Joy Nigel Maxted The aim of this study was to produce a classification, firstly of the relationships between the legume genus Psophocarpus and its allies and secondly, between Psophocarpus species. TO provide a background and to clarify the problems associated with Psophocarpus taxonomy the taxonomic history of Psophocarpus species and their allies was reviewed. Due to the large number of taxa involved in the investigation (approx. 489 species) and that these taxa are endemic to the tropics, practically the investigation was limited to morphological studies of herbarium material gathered from major herbaria. Both phenetic and phylogenetic studies of the material were undertaken. The phenetic investigation was divided into four component studies: the survey of 31 genera of the Phaseolinae (sensu Lackey, 1977a); the detailed study of a subset of seven genera shown in the previous survey to be most closely allied to Psophocarpus} the study of the nine Psophocarpus species and the study of the two closely allied species P.palustris and P.scandens. A gross character set was formulated of 315 morphological characters, containing vegetative, floral, legume and seed characters. From this appropriate character sets were selected for the component studies. The choice of characters waus largely intuitive, but an objective character analysis program was also utilised. Over 800 specm^ns were scored aiid the data were analysed using both cluster analysis and ordination methods. The phylogenetic investigation used the cladistic method of analysis and may be separated into two component studies: the six Psophocarpus allied genera study and the Psophocarpus species study. Apomorphic characters were selected and character state polarity ascribed to each, nested synapomorphies were found and cladograms produced for both studies. After extensively reviewing the non—morphological evidence available in the literature classifications were proposed at the generic and specific levels. Separate phenetic and f^ylogenetic classifications proposed for the relationship between Psophocorpus ^species classification. In the discussion these classifications are reviewed in the light of other workers concepts, as well as discussing the n^thods used and suggesting areas for future research. and ife closB. (a\Ue,s as cotdci noV Ian. ti>arne.cl to ^rm one. geoeroL classiccai"!on, However, was fios&\b\fl. ttvE. prepose.ci PsopKocarpuS (ill) CONTENTS Dedication (i) Acknowledgements (ii) Abstract (iii) Contents (iv) CHAPTER ONE General Introduction 1 1.1 Problem elucidation 1 1.2 Aims 2 1.3 Delimitation of taxon study 3 1.4 Plan 7 CHAPTER TWO Taxonomic History of Psophocarpus within the Phaseoleae 11 2.1 Introduction 11 2.2 The taxonomic history of Psophocarpus as a member of the Phaseoleae 18 2.3. Taxonomic history of Psophocarpus species 44 CHAPTER THREE Introduction to Data Gathering and Analysis 57 3.1 Introduction 57 3.2 Choice of operational taxonomic units 58 3.2.1 Theoretical foundation 58 3.2.2 Reasoned choice of OTU's 59 3.3 Choice of characters 60 3.3.1 Theoretical foundation 60 3.3.2 Reasoned choice of characters 67 3.4 Choice of phenetic analysis 69 3.4.1 Theoretical foundation 69 3.4.2 Reasoned choice of phenetic method 76 (a) LINKAGE 76 (b) CLUSTAN IC 81 (C) DECORANA 89 3,5 Choice of phylogenetic analysis 92 3.5.1 Theoretical foundation 92 3.5.2 Reasoned choice of phylogenetic analysis techniques 95 (iv) CHAPTER FOUR Phenetic Chciracter Set Selection 101 4.1 Introduction lOl 4.2 Gross character set 102 4.3 Character subset selection 138 CHAPTER FIVE Phenetic Studies Analysis Results 151 5.1 Introduction 151 5.2 Extensive inter-generic survey for 151 PsophocarpuB allies 5.2.1 LINKAGE 151 5.3 Intensive inter-generic survey for close Psophocarpus allies 160 5.3.1 LINKAGE 161 5.3.2 CLUSTAN (DISTIN) 181 5.3.3 CLUSTAN (FILE) 185 A - Ward's method 186 B - principal Components Analysis 189 5.3.4 DECORANA 199 5.4 Intra-generic Psophocarpus study 200 5.4.1 LINKAGE 203 5.4.2 CLUSTAN (DISTIN) 214 5.4.3 CLUSTAN (FILE) 216 A - Ward's method 216 B - Principal Components Analysis 219 5.4.4 DECORANA 223 5.5 Psophocarp-us palustrts - P. scandens 226 Complex study 5.5.1 LINKAGE 226 5.5.2 CLUSTAN {DISTIN) 228 5.5.3 CLUSTAN (FILE) 230 A - Waxd's method 230 B - Principal Components Analysis 231 5.5.4 DECORANA 236 5.6 Suiratary of phenetic studies results 236 5.6.1 Inter-generic survey for Psophocarpns 238 allies 5.6.2 Intra-generic survey for Psophocarpus 239 species 5.6.3 Psophocarpus patustrts - P. scandens 240 complex study CHAPTER SIX Cladistic Analysis Results 241 6.1 Introduction 241 6.2 Selection of aporoorphies 242 6.2.1 Six genus cladistic analysis 242 6.2.2 Psophocarpus species cladistic analysis 242 6.3 Construction of cladograms 246 6.3.1 Six genus cladistic analysis 246 6.3.2 Psophocarpus species cladistic amalysis 249 CHAPTER SEVEN Non-morphological evidence 254 7.1 Introduction 254 7.2 Ptiytogeographical evidence 254 7.3 Cytotaxonomic evidence 269 7.4 Biosystematic evidence 277 7.5 Palynological evidence 280 7.6 Anatomical evidence 288 7.7 Chemotaxonomic evidence 295 7.8 Seedling evidence 302 7.9 Other evidence 305 7.10 Sunnnary of non-morphological evidence 311 CHAPTER EIGHT Proposed Classification and Discussion 316 8.1 Introduction 316 8.2 Proposed classification 316 8.2.1 proposed classification of Psophocarpus 317 and its close allies 8.2.2 Proposed classification of Psophocarpus 320 species 8.3 Discussion of proposed phenetic classifications 322 8.3.1 Discussion of proposed inter-generic 322 classification 8.3.2 Discussion of proposed intra—generic 325 classification 8.4 Discussion of phenetic characters 327 8.5 Discussion of phenetic analysis 335 8.6 Discussion of phylogenetic analysis 338 8.7 Suggested future research 344 REFERENCES 346 APPENDICES 365 CHAPTER ONE GENERAL INTRODUCTION 1.1 Problem elucidation Much current tropical agricultural reseaurch is being concentrated on locating and developing underexploited crops as one step towards alleviating the Third World protein deficit. One legume crop that has proved particularly interesting in this context is the winged bean, Psophocarpus tetragonolobus (L.) DC. The United States National Academy of Science refers to the winged bean (NAS 1975) sis "a legume with a multitude of exceptionally large nitrogen-fixing nodules . producing seeds, pods and leaves (all edible to humans and livestock) with exceptionally high amounts of protein amd edible seed oil". Haq (198%) underscores the possibilities of turning the winged bean from a •backyard' plant of South and South East Asia to a field scale crop of the entire tropics. Before any crop can be efficiently exploited it is essential that the crop's systematic relationships with other species of the same genus and with species of allied genera are cleeirly understood.