GERMINATION, GROWTH, FLOWER PRODUCTION AND QUALITY OF BUTTERFLY PEA (CLITORIA TERNATEA): A PLANT WITH A UNIQUE PH-DEPENDENT SENSORY QUALITY By SEAN MICHAEL CAMPBELL A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2020 © 2020 Sean Michael Campbell To my family and friends for helping to support me along the way ACKNOWLEDGMENTS I thank my parents for all of their love and support, and all my family and friends for helping me along the way. I also thank Dr. Brian Pearson for being a mentor and role model, and the rest of my graduate committee for their guidance in this accomplishment. 4 TABLE OF CONTENTS page ACKNOWLEDGMENTS ...............................................................................................................4 LIST OF TABLES ...........................................................................................................................8 LIST OF FIGURES .........................................................................................................................9 ABSTRACT ...................................................................................................................................11 CHAPTER 1 A HORTICULTURAL REVIEW OF BUTTERFLY PEA (CLITORIA TERNATEA) BOTANY, GROWING ENVIRONMENT, SEED GERMINATION, AND CULTIVATION .....................................................................................................................13 Botany .....................................................................................................................................16 Leaves ..............................................................................................................................16 Flowers ............................................................................................................................17 Pods and Seeds ................................................................................................................18 Roots ................................................................................................................................19 Growing Environment ............................................................................................................20 Seed Germination ...................................................................................................................21 Seed Moisture Content ....................................................................................................22 Scarification .....................................................................................................................23 Temperature .....................................................................................................................24 Cultivation ..............................................................................................................................26 Planting and Harvest Date ...............................................................................................27 Light ................................................................................................................................29 Planting Density ..............................................................................................................30 Soil ...................................................................................................................................31 Soil Moisture Content ......................................................................................................33 Rooting Hormone ............................................................................................................35 Fertilization ......................................................................................................................36 Nitrogen Fixation .............................................................................................................38 Natural Enemies ..............................................................................................................38 Butterfly Pea (Clitoria ternatea) Flower Extract (BPFE) and Its Use as a pH-Dependent Natural Colorant ..................................................................................................................39 Color-Changing Anthocyanin .........................................................................................40 Extraction ........................................................................................................................41 Storage and Processing ....................................................................................................43 Antioxidant and Other Benefits .......................................................................................45 Conclusion ..............................................................................................................................45 2 INFLUENCE OF SUBSTRATE TYPE AND TEMPERATURE ON GERMINATION OF BUTTERFLY PEA...........................................................................................................59 5 Materials and Methods ...........................................................................................................61 Seed .................................................................................................................................61 Substrate Type .................................................................................................................61 Substrate Temperature .....................................................................................................62 Germination Parameters ..................................................................................................62 Experimental Design .......................................................................................................63 Results.....................................................................................................................................64 Temperature and Humidity ..............................................................................................64 Germination Parameters ..................................................................................................64 Discussion ...............................................................................................................................66 Conclusions.............................................................................................................................67 3 INFLUENCE OF SUBSTRATE TEMPERATURE AND SEED SCARIFICATION ON GERMINATION OF BUTTERFLY PEA (CLITORIA TERNATEA). ...................................73 Materials and Methods ...........................................................................................................74 Seed Scarification ............................................................................................................74 Substrate ..........................................................................................................................74 Substrate Temperature .....................................................................................................75 Germination Parameters ..................................................................................................76 Experimental Design .......................................................................................................77 Results.....................................................................................................................................77 Discussion ...............................................................................................................................79 Conclusion ..............................................................................................................................80 4 GROWING STRUCTURE AND ITS EFFECT ON FLOWER PRODUCTION IN BUTTERFLY PEA (CLITORIA TERNATEA) .......................................................................87 Materials and Methods ...........................................................................................................88 Plant Propagation .............................................................................................................88 Growing Structures ..........................................................................................................90 Data Collection and Analysis ..........................................................................................91 Results and Discussion ...........................................................................................................92 Conclusion ..............................................................................................................................94 5 INFLUENCE OF FERTILIZATION AND IRRIGATION ON GROWTH CHARACTERISTICS AND FLOWER PRODUCTION IN BUTTERFLY PEA (CLITORIA TERNATEA) ........................................................................................................99 Materials and Methods .........................................................................................................100 Butterfly pea (Clitoria ternatea) ...................................................................................100 Irrigation ........................................................................................................................102