Preserving Orchids:  UF/IFAS is creating a frozen seedbank

The globe-trotting Wagner Vendrame, UF/IFAS faculty member stationed at the Tropical Research and Education Center (TREC), traveled to Santo Domingo, the capital city of the Dominican Republic, from October 8-15th to present a poster at the 51st Interamerican Society for Tropical Horticulture (ISTH) annual meeting.  The poster detailed the research work performed in his laboratory on the cryopreservation of orchid seeds.  Vendrame was also nominated to serve as a member at large for the society and to be the associate editor for the ornamental section of the meeting proceedings.

Vendrame’s research is aimed at preserving rare and endangered orchids through cryogenic preservation of orchid seeds.  Vendrame is creating a method to freeze orchid seeds indefinitely, thus creating a frozen seedbank.  He selected the “Jaquelyn Thomas” Dendrobium orchid for the study, which is a popular cultivar of commercial interest.  “We have tested seed viability after freezing to make sure seeds survived and germinated after submitted to cryopreservation,” Vendrame said.  The main premise is that, since cryopreservation involves freezing at very low temperatures, - 196 C, if seeds survive for 72 hours under that temperature, they would be able to survive indefinitely.  Vendrame succeeded in germinating more than a fifth of the orchid seeds (22%) after keeping them frozen for two weeks.

The key to success is the pre-freezing treatment of seeds.  Before freezing them in liquid nitrogen, the seeds were exposed to a dessicating agent and low temperatures in a process called “vitrification.” This dried and pre-cooled the seeds, eliminating the damage that would otherwise have occurred during the freezing process.  Vitrification is a perfect alternative for the conservation of orchid seeds because it is quick, simple, reliable, and low-cost.  Vendrame’s lab tested several pretreatments to identify which one would provide the best protection for the seeds under cryopreservation.  Once the seeds were removed from cryopreservation, Vendrame tested them for viability and placed them for germination, evaluating the percentage of germination for each treatment.

Vendrame said the technique is promising and that his lab intends to continue experiments in this area.  The technique can also be applied to orchid shoots and protocorms, little round green structures that form once seeds start germinating.  (See photo illustration)  It has great potential for conservation of endangered orchid species, but also for preservation of material for use in orchid breeding programs.

This is valuable research for Florida’s orchid industry, since orchids are now the second-most-popular potted flowering plant produced in Florida, behind only poinsettias.  Annual farmgate sales total more than $23 million.  As the fastest-growing segment of America’s $13 billion floriculture and nursery crops industry, orchid production in Florida is booming.  Vendrame’s expertise in orchid propagation positions him as a valuable resource to the industry and the state’s economy.  Located in the heart of Florida’s orchid-growing industry at the TREC’s facility in Homestead, Vendrame’s research not only supports the industry, it carries him far beyond Florida’s borders to present research results, conduct cooperative research, and lend his expertise to opening new markets for Florida’s tropical horticultural products (see A Blossoming Relationship: UF/IFAS joins trade mission to South Africa).

Vendrame’s cryogenic preservation technique is just one portion of his effort to preserve and propagate Florida’s native orchid species.  He is particularly interested in preserving orchids that are rare or endangered, but could be mass-propagated to preserve them, as both commercial landscape plants and through large-scale re-introduction into the wild. (See UF/IFAS IMPACT Magazine Vol. 20, No. 2, Summer 2004 (pdf).

The ISTH annual meeting was an ideal venue for Vendrame to present his research.  ISTH focuses on tropical agriculture and is the only scientific society in the Americas wholly dedicated to collecting and disseminating information on the production of tropical horticultural crops.  The society does this through its newsletter and its annual meeting’s proceedings.  The meetings included presentations (oral and posters) on production of tropical vegetables, fruits, and ornamentals.  The annual meeting gathers a large number of researchers from North, Central, and South America who are working on crops of interest to the United States and also of common interest for researchers, such as those at TREC.

In addition to presenting the poster, the meeting also allowed Vendrame to meet with several researchers from different countries who demonstrated interest in visiting TREC and participating in collaborative research efforts.  He was able to establish good contacts with researchers working on ornamental species that could generate a mutual benefit for research programs, both in the US and in the collaborative researcher’s country.  In particular, he met researchers from three Brazilian institutions, including two universities and a governmental research agency, plus researchers from Venezuela, Chile, Dominican Republic, and several other countries, including the U.S.A.’s University of Massachusetts.

Vendrame believes other UF/IFAS faculty may be interested in the opportunity ISTH provides for internationalizing a research program.  According to Vendrame, “…this society provides a good means for dissemination of research performed with tropical and subtropical species, as well as a good means for interacting with researchers at the international level. This also provides a good opportunity for faculty to establish international cooperation agreements with peers in Latin America.”  Two of Vendrame’s partners in the cryogenic preservation of orchid seeds project are Jose M. M. Dias and Virginia S. Carvalho, from the Departamento de Fitotecnia, Universidade Federal de Viçosa, in Brazil.  The other researcher on the team is Pamela A. Moon from the UF/IFAS TREC.

Of interest to TREC supporters is the organizing work done by Noris Ledesma, the current ISTH Assistant Secretary –Treasurer, who helped organize the 51st annual meeting.  She works for Fairchild Tropical Gardens in Miami under Dr. Richard Campbell, son of Dr. Carl Campbell, who was the founder of ISTH and a former professor at the UF/IFAS TREC, in Homestead.  UF/IFAS has established a proud history of long-lasting, far-reaching impact in the area of pan-American tropical horticulture.

History of ISTH

Founded in 1951 as the Caribbean Region group of the American Society for Horticultural Science (ASHS), the society underwent two name changes, becoming the American Society for Horticultural Science—Tropical Region in 1966, in recognition of members from outside the Caribbean region.  In 1986, legal reasons necessitated the separation of this organization from ASHS, prompting the second name change to the Interamerican Society for Tropical Horticulture.  The annual meeting moves from country to country each year, cooperating with local and/or international governments, educational institutions, and agricultural organizations.  The latest applied research results are disseminated through the meetings, which also include study trips to local agricultural production areas.  The papers from each meeting are published in the Proceedings of the Interamerican Society for Tropical Horticulture annual journal.  ISTH maintains a membership of three hundred ten members from thirty-five nations.  ISTH helps these widely scattered members stay in contact through its biannual newsletter and its web site, which features recent information released by ISTH and also contains searchable proceedings, creating a valuable database of information. 

Contact: Wagner Vendrame

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