Lankesteriana International Journal on Orchidology ISSN: 1409-3871 [email protected] Universidad de Costa Rica Costa Rica STEWART, SCOTT L.; KANE, MICHAEL E. ORCHID CONSERVATION IN THE AMERICAS—LESSONS LEARNED IN FLORIDA Lankesteriana International Journal on Orchidology, vol. 7, núm. 1-2, marzo, 2007, pp. 382-387 Universidad de Costa Rica Cartago, Costa Rica Available in: http://www.redalyc.org/articulo.oa?id=44339813080 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative LANKESTERIANA 7(1-2): 382-387. 2007. ORCHID CONSERVATION IN THE AMERICAS—LESSONS LEARNED IN FLORIDA 1,2 1 SCOTT L. STEWART & MICHAEL E. KANE 1 Environmental Horticulture Department, University of Florida, PO Box 110675, Gainesville, Florida, USA 2 Author for correspondence: [email protected] KEY WORDS: asymbiotic germination, conservation, Florida, pollination biology, symbiotic germination Introduction integrated conservation efforts at the species level. To date, the partnership has initiated research examining Conservation can be a difficult concept to define, various factors of the ecology, biology, and propaga- let alone apply. For some, plant conservation can tion of several native Florida orchids, including Bletia simply mean the survey and cataloging of plant diver- purpurea (Lamark) de Candolle, Cyrtopodium punc- sity within a defined conservation area. Others may tatum (Linnaeus) Lindley, Dendrophylax lindenii define plant conservation as the collection and propa- (Lindley) Bentham ex Rolfe, Eulophia alta gation of germplasm from one, or many, areas within (Linnaeus) Fawcett & Rendle, Habenaria macrocer- a species’ range. Still others may define plant conser- atitis Willdenow, Prosthechea cochleata (Linnaeus) vation as the act of plant translocation for population W.E. Higgins var. triandra (Ames) W.E. Higgins, reintroduction, establishment, or augmentation. Spiranthes floridana (Wherry) Cory emend. P.M. Traditionally, many plant conservation researchers Brown, and S. odorata (Nuttall) Lindley. Through the have focused efforts on only one or two of these use of field observations of plants and pollinators, actions and defined their efforts as effective species- isolation and characterization of mycobionts, symbi- level conservation. These researchers have treated otic and asymbiotic seed germination, and the study species-level conservation as a set of individual steps of population genetic diversity by amplified fragment that have little, or no, interconnection. Orchid species length polymorphism (AFLP), the partnership has conservation has traditionally taken on this separated been able to demonstrate the applicability of integrat- approach. Few of the many traditional orchid conser- ed conservation methods for the conservation of vation efforts have taken into account one integrated orchid species in Florida. picture of the orchid plants, their pollinators and The acceptance and application of these methods reproduction, their mycobionts, their propagation, and outside of Florida is now needed to further demon- their population genetic diversity. strate their effectiveness on a global scale. The meth- Florida is home to approximately 120 orchid ods, successes, failures, and tribulations of identify- species and a number of other growth and color forms ing and addressing integrated orchid conservation and varieties (Brown 2005). While nearly all of these needs in Florida will be discussed. Additionally, sev- species are considered endangered, threatened, or eral case studies will be outlined will be used to eluci- commercially-exploited, few have received any con- date these methods. One example case study on H. servation attention and even less have received atten- macroceratitis is presented here. tion from those interested in integrated conservation. In 2002 the Plant Restoration, Conservation, and Case Study Propagation Biotechnology Program at the University of Florida (Gainesville, Florida) established a partner- Habenaria macroceratitis.—The following is a ship with the Florida Panther National Wildlife brief case study outlining the major areas of research Refuge (Naples, Florida) aimed at conserving the concerning the integrated conservation of H. macro- orchids of Florida through the implementation of ceratitis in Florida. At the time of writing, some data STEWART & KANE - Orchid Conservation in Florida 383 concerning the species’ ecology, pollination biology, and population genetic diversity was not fully ana- lyzed and, therefore, not presented in the current paper. PLANT ECOLOGY. Habenaria macroceratitis is a rare sub-tropical terrestrial orchid native to central Florida, Mexico, the West Indies, and Central America (fig. 1). The species typically inhabits moist hardwood hammocks in Florida where the canopy is dominated by Quercus virginiana (live oak), Magnolia grandiflora (magnolia), Liquidambar styraciflora (sweet gum), Pinus elliottii (slash pine), P. palustris (long-leaf pine), and Sabal palmetto (cabbage palm) (S.L. Stewart, unpub. data 2003). The loss of hardwood hammock habitat throughout Florida has prompted interest by researchers and state agencies in the preservation and restoration of these critical habitats (Maehr & Cox 1995, Sprott & Mazzotti 2001). Many native Florida terrestrial orchids, including H. macroceratitis, inhabit this threatened habitat (S.L. Stewart, pers. observ. 2003) and unless effective species-level conservation meth- ods are developed, these species are likely to face population decline or extinction. The integrated con- servation of Habenaria macroceratitis, the long- horned rein orchis, was investigated through an examination of the species’ ecology, mycology, propagation science, pollination biology, and popula- tion genetic diversity. Four populations of H. macroceratitis were identi- fied in west-central Florida representing various pop- FIGURE 1. Habenaria macroceratitis inflorescence in habitat. ulation sizes and conservation statuses. One of the populations was considered large (Hernando County graphics, and habitat characterization were collected. #1, 270 plants) and existed on privately-owned land At the time of writing, these data are currently being that was being adaptively managed for the orchid- analyzed for associations among habitat/environmen- appropriate habitat. The second population was con- tal factors and whole plant responses. sidered of moderate size (Hernando County #2, 65 plants) and existed on privately-owned land with no PLANT MYCOLOGY. — Fifteen mycobionts were iso- management being applied. The final two popula- lated from the roots of H. macroceratitis collected at tions were considered small (Marion County, 16 two of the previously mentioned populations plants; Sumter County, 10 plants), with the Marion (Hernando and Sumter Counties) following the meth- County population existing on managed state-owned ods outlined by Zettler (1997) and Stewart and Zettler land and the Sumter County population existing on (2002). Six of the mycobionts were assignable to the privately-owned non-managed land. Data concerning anamorphic fungal genus Epulorhiza Moore, while flowering versus vegetative production, plant demo- the remainder were assignable to the anamorphic LANKESTERIANA 7(1-2), marzo 2007. © Universidad de Costa Rica, 2007. RD 384 3 IOCC PROCEEDINGS genus Ceratorhiza Moore, based on cultural morphol- and seedling development (Stewart & Kane 2006a). ogy, microscopic examination, and enzyme assays. Subsequently, the effect of three photoperiod treat- These mycobionts were subsequently used in a num- ments (0/24, 16/8, 24/0 h L/D) on asymbiotic seed ber of studies investigating the in vitro symbiotic seed germination were evaluated. Seeds incubated in con- germination of H. macroceratitis. These data suggest tinual darkness (0/24 h L/D) exhibited the highest that H. macroceratitis may demonstrate a degree of final percent germination (91.7%) and the most fungal specificity based upon geographic area in cen- advanced protocorm developmental stage (Stage 4, tral Florida. Therefore, to insure the conservation of fig. 2, Stewart & Kane 2006a). Although seed germi- this species through symbiotic seed germination nation under both 16/8 and 24/0 h L/D treatments was mycobionts from many populations throughout the stimulated, percent germination was statistically species’ Florida range should be isolated, character- lower (fig. 2, Stewart & Kane 2006a). These data ized, and cataloged. reinforce the notion that, in general, seeds of terrestri- al orchid species are best germinated in continual PLANT PROPAGATION. — Of particular interest was darkness and that exposure to light may inhibit germi- the development of a reliable symbiotic seed germi- nation or protocorm development. nation method that accounted for any potential To further examine in vitro growth and develop- mycobiont specificity based on seed collection and ment of H. macroceratitis, the effects of three pho- mycobiont collection sites. Current data suggest that toperiod treatments (8/16, 12/12, 16/8 h L/D) on in symbiotic germination of this species is possible and vitro seedling development was evaluated. Asymbiotic that this species does demonstrate a degree of myco- seedlings grown under a 8/16 h L/D photoperiod pro- biont specificity when seeds and mycobiont collect- duced