University of Central Florida STARS Retrospective Theses and Dissertations 1984 A Biosystematic Study of the Fern Genus LYGODIUM in Eastern North America Violet M. Brown University of Central Florida Part of the Biology Commons Find similar works at: https://stars.library.ucf.edu/rtd University of Central Florida Libraries http://library.ucf.edu This Masters Thesis (Open Access) is brought to you for free and open access by STARS. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of STARS. For more information, please contact [email protected]. STARS Citation Brown, Violet M., "A Biosystematic Study of the Fern Genus LYGODIUM in Eastern North America" (1984). Retrospective Theses and Dissertations. 4726. https://stars.library.ucf.edu/rtd/4726 A BIOSYSTEMATIC STUDY OF THE FERN GENUS LYGODIUM IN EASTERN NORTH AMERICA BY VIOLET M. BROWN B.S., University of Central Florida, 1980 THESIS Submitted in partial fulfillment of the requirements for the Master of Science degree in Biological Sciences in the Graduate Studies Program of Arts and Sciences University of Central Florida Orlando, Florida Spring Term 1984 ABSTRACT The mainly tropical genus Lyqodium differs from other ferns in that the fronds are indeterminate and are vine-like. A single species, L. palmatum is native in temperate North America. The temperate Asian L. japoni­ cum is naturalized throughout much of the southeastern United States. About twenty years ago, L. microphyllum was introduced into South Florida and is now naturalized in several counties. The present study documents differences among spores and their generation, development of sporo­ phytes from the fertilized egg, and in flavonoid chemistry. Hybridization experiments showed a strong possibility for cross fertility between species. Experiments with prothal­ lial development and differentiation revealed that environ­ ment influenced variation and gametangium formation. Greater similarity in sporophyte developmental stages and in frond phyto'chemistry show that the native h palmatum is phenetically closer to the tropical L. microphyllum than to L. japonicum. All three species are clearly distinct at all levels examined. C 1984 by Violet M. Brown ACKNOWLEDGEMENTS When I consider the pleasant obligation of expres­ sing appreciation to those who have helped in this study, I find the task awesome. Fa.. r too many will remain nameless as so often the help may have been only a word that was needed. Some I remember, some are lost to me. For every kindness, for all encouragements, and for all the challenges given, I am thankful. In particular, I am grateful to my sister, Mildred Deese Irving for finding the population of Lygodium micro­ phyllum in Palm Beach County which initiated my interest in doing this study. To my brother, Edwin Deese, who stood wild hog, water meccas in, and alligator guard with a rifle while we were swamp tromping, my admiration and appreci­ ation. To Dr. Henry O. Whittier who began as my freshman advisor and over the years has become my professor, mentor, philosopher, friend, a family member, father confessor and • member of my graduate committee, without whose unstinting help, encouragement, equipment and patience this would never have come to fruition, I will be eternally grateful. Dr. Harvey A. Miller has had a profound effect on stimulating my interest in the botanical sciences, stretch- iii ing my understanding of interrelationships of the bio­ sphere. I have become a better person for having had his di­ rection and understanding. Thank you for all you have given. Dr. Roseann White has been of much help in phyto­ chemical procedures and interpretations. Thank you. Dr. Ritchie Bell sent material of Lyqodium palma­ turn to me when I was desperate for it. Thank you so much. To my niece, Sherry Bailey, who has understood all of my problems from the beginning and has done the typing at the last minute, my undying love and appreciation. To Dr. Franklin Snelson for the use of his person­ al drawing microscope, Dr. David Vickers for space in the growth chamber, and all of the other professors here who have helped in various ways, thank you. The largest contribution came from my husband, Frank Brown. He has given me eight years of college with all the pleasures and liabilities associated with them, shared my successes and failures, joys and tears, triumphs and tragedies, and still kept his wallet and arms open. I think I will keep him around. iv TABLE OF CONTENTS LIST OF FIGURES vi LIST OF TABLES viii INTRODUCTION 1 Taxonomic History of the Genus 2 Species of Eastern North America 6 DEVELOPMENTAL STUDIES 8 Materials and Methods 8 Experimental Populations 8 Establishmentof Cultures 9 Breeding Experiments 12 Regeneration Experiments 12 Results 13 Developmental Patterns 13 Breeding Results 16 Regeneration Results 17 PHYTOCHEMICAL STUDIES 19 Materials and Methods 19 Results 21 DESCRIPTIVE STUDIES AND TAXONOMIC TREATMENT 32 Key to Species 32 Lyqodiurn iaponicurn 33 Lygodiurn rnicrophyllurn 41 Lyqodiurn palrnaturn 59 DISCUSSION AND CONCLUSIONS 71 LITERATURE CITED 78 LIST OF FIGURES FIGURES PAGE 1. A single frond of Lygodium microphyllum showing the vine-like habit characteristic of the genus . • . .. 4 2. A composite two-dimensional chromatograph of chemical isolates from the pinnae blades of Lyqodium iaponicum . • • • • . .. 22 3. A composite two-dimensional chromatograph of chemical isolates from the rachises of Lyqodium iaponicum • • • . • . .. 23 4. A composite two-dimensional chromatograph of chemical isolates from the pinna blades of Lygodium microphyllum. • . •. 24 5. A composite two-dimensional chromatograph of chemical isolates from the rachises of Lygodium microphyllum. • • • • . • . • •. 25 6. A composite two-dimensional chromatograph of chemical isolates from the pinna blades of Lygodium palmatum. • • • • • • • • . .• 26 7. A composite two-dimensional chromatograph of chemical isolates from the rachises of Lygodium palmatum. • • . • • . • . .. 27 8. A computer generated dendrograph showing the relationships among Lyqodium iaponicum, h microphyllum and h palmatum pinna blades and rachises based upon chemical isolate similarities and differences • . • . •.••• 28 9. Lygodium iaponicum habit as seen on an herbarium specimen • . • . • • • . • ••... 38 10. Lygodium japonicum detail of fertile and sterile pinnae • • . • . • • • ••.. 40 11. Lyqodium microphyllum habit of pinnae on the frond. • . • • • . • . ...• 46 vi LIST OF FIGURES (continued) FIGURES PAGE 12. Lyqodium microphyllurn habit of base of plant including the rhizome and roots .......... 48 13. Lygodium microphyllurn detail of fertile pinnae . .so 14. Lygodium microphyllum detail of sterile pinnae . .52 15. Lyqodiurn microphyllurn detail of sterile pinnae . .54 16. Lyqodium microphyllum detail of sterile pinnae . .56 17. Lyqodium microphyllurn detail of sterile pinnae . .58 18. Lyqodiurn palmatum habit of pinnae on the frond. • . • . .•• • • • • 6 4 19. Lyqodium palmatum detail of fertile pinnae as seen on an herbarium specimen ...• .66 20. Lygodiurn structures and development. • • • 6 8 21. Lygodium structures and development. .70 vii • LIST OF TABLES TABLES PAGE 1. Explanation of chromatographic spots and their distribution among Lygodium japonicum {japon), h microphyllum {micro), and h palmatum {palm), with Rf values (X 100) ...••• 30 viii INTRODUCTION Early in 1977 while I was visiting my family in Palm Beach County and collecting botanical specimens in vari­ ous areas of the Everglades, my sister found a species of clinging fern. I recognized its similarity to Lyqodium iaponicum, but was unfamiliar with the species. Several herbarium specimens were collected and brought to Dr. Henry 0. Whittier for identification. We tentatively identified it as Lyqodium microphyllum and I began searching the literature to find as much as possible about it. Little was known, and I was able to find only one illustration of a fer­ tile pinna with no illustrations for vegetative blades. In­ trigued, Dr. Whittier and Dr. Miller encouraged me to learn as much as I could about the species. Each time I returned to Palm Beach County, I visited the original population, noting the changes. Later, I attempted germinating the spores, then tried doing paper chromotography of flavonoid extracts. The results were fascinating, so I then attempted parallel studies of Lyqodium japonicum which had ap­ peared as a volunteer in my yard in 197 4. Upon acceptance in the Biological Sciences graduate program at the Univer­ sity of Central Florida, the biosystematic study a the three 2 species of Lyqodium found in the United States seemed to be a work worthy of future study. Taxonomic History of the Genus The genus Lygodium is pantropical to subtropical and is comprised of 30 to 40 species. Taxa are known from the Eastern United States, South America, New Zealand, Aus­ tralia, S.E. Asia, Africa, Indomalaya, the Pacific Islands, and north to Japan. Fossil records are found dating from the lower Cretaceous and Tertiary in Siberia, Europe, China and America. Copeland (1947) recognized 39 species, Holttum ( 1960) counted about 40 species and Tryon and Tryon (1982) reported the genus to contain about 30 species. Lyqodium is a natural genus, so homogenous be­ cause of the vine-like indeterminate fronds (Figure 1) that there is presently little agreement on division into sub­ groups. From 1800 to 1803 botanists around the world saw the first species of Lyqodium resulting from numerous bo­ tanical expeditions into the tropics.