A Review of Germplasm Collection Efforts and Conservation Potential

Ames, Iowa, is home to an important new medicinal plant germplasm collection in the United States. The North Central Regional Plant Introduction Station (NCRPIS) in Ames is part of a network of more than 25 active germplasmconservation sites coordinated by the US Department of Agriculture (USDA) within the Agricultural Research Service’s (ARS) National Plant Germplasm System (NPGS). These germplasm repositories, called genebanks, are the storehouses for maintaining genetic diversity within accessions of crop plants and their native relatives. Another program, called Seeds of Success (SOS), is working to establish the largest living collection of seeds from native plants in the United States. These programs represent just two of numerous seed collection efforts around the country. What makes them special is the emphasis on native plants, which reflects an important trend in conservation involving many federal and non-federal partners. Collecting this germplasm and preserving the genetic material that controls heritable traits of native plants will allow researchers to maintain and restore native landscapes more effectively. In the face of increasing concerns about the growing problem of invasive species, the timing could not be better.

Retrieving seed samples from a -18° C (0° F) storage vault for distribution to NCGRP sites for cultivar development and study of the species. Photo ©2007 United States Department of Agriculture

Germplasm and Genebanking

Germplasm conservation in the United States is nothing new. Realizing the importance of genetic diversity, the USDA has been collecting and preserving germplasm since the late 1800s. However, farmers and plant breeders were selecting for desirable traits long before Mendel’s Laws of Genetics were formally described.¹ This domestication process often leads to the loss of important genetic diversity. For example, of the more than 7,100 named apple varieties grown in the United States since the 1800s, more than 6,800 no longer exist.² This loss in variation may reduce a species’ genetic diversity, making it more vulnerable to pests, diseases, and environmental change. The key to protecting against the total loss of these important genetic traits lies in the preservation of their wild relatives. Genebanking, collecting, and preserving plant germplasm attempts to recapture and preserve this genetic diversity.

Agricultural crops have long been the primary focus of germplasm collections. Bioversity International, an organization coordinating the conservation of genetic resources worldwide, reports that almost 95% of the genetic diversity of global staple crops such as rice, wheat, and maize is held safely in genebanks.³ Unfortunately, native species, including many medicinal plants, are not as well-represented as their commercial crop cousins in germplasm collections. Fortunately there is an emerging emphasis on seed collection efforts that focus on native species, including medicinals.

A Shift toward Native Plants for Restoration Efforts

In the early 1990s, US public land management agencies began to look toward native species for restoration activities following habitat-disrupting disasters, such as wildfires.⁴ Particularly devastating wildfires in 1999 prompted the US Congress to direct the agencies to develop a long-term program to manage and supply native plant materials for use in various federal land management restoration and rehabilitation needs. Congress further recommended that the Plant Conservation Alliance (PCA), a consortium of federal and non-federal partners, lead this effort.

The SOS program is PCA’s response to this mandate through an agreement with the Bureau of Land Management (BLM). An interagency partnership coordinated through the PCA in cooperation with the Royal Botanic Gardens, Kew, United Kingdom, the SOS program supports and coordinates seed collection of native plant populations in the United States to increase the number of species and the amount of native seed available for stabilizing, rehabilitating, and restoring public lands. The program also provides source identified seed and germination findings that are critical to the development and large-scale production of new native plant materials. SOS partners include the BLM, USDA Forest Service, USDA ARS, US Department of Defense, the US Fish and Wildlife Service, the Chicago Botanic Garden, the Lady Bird Johnson Wildflower Center, Mt. Cuba Center, Inc., the North Carolina Botanic Garden, the New England Wildflower Society, the New York City Department of Parks and Recreation with the Brooklyn Botanic Garden, the Zoological Society of San Diego, and Center for Plant Conservation Gardens.

These partnering organizations and federal agencies are cooperating to produce the largest native seed collection in the United States. The end of the 2006 field season marked the collection of more than 2,000 unique taxa to be maintained in genebank facilities in Pullman, WA (USDA, ARS); Bend, OR (USDA, Forest Service); and Kew, United Kingdom. These collections represent about one-third of the 7,900-species collection goal for the United States.

Retrieving seed samples from a -18° C (0° F) storage vault for distribution to NCGRP sites for cultivar development and study of the species. ©2007 United States Department of Agriculture

Parent populations from each of the 2,000 collections have been carefully monitored (often for several growing seasons), identified by a taxonomist or well trained botanist, and generally consist of a minimum of 10,000 viable seeds. When collectors initially target a population for collection, they must adhere to the genetic sampling standard outlined in the SOS Protocol. Collection documentation consists of at least 2 herbarium vouchers (one for Kew and one for the US National Herbarium at the Smithsonian Institution), a completed field data form that captures everything from the associated taxa to the geology of the collection site to the number of plants sampled, and digital images. A sample field data form is available on the SOS Web site (www.nps.gov/plants/sos). All collection information is databased at the BLM and is made available for researchers interested in working with SOS material.

Native Plants for Cultivation and Research

The NPGS is another cooperative effort between state and federal agencies in the United States to preserve the genetic diversity of plants. Beginning with the establishment of four regional stations in 1948, the NPGS has evolved into a coordinated national system and has assembled many important germplasm collections of crop species from both domestic and international sources. The mission of the NPGS includes the conservation of diverse crop germplasm through collection, acquisition and exploration, conducting a variety of germplasm-related research, and encouraging the use of the collections and associated information for research, crop improvement, and product development.

More specifically, the process includes the following:

1. Collection of germplasm through acquisition and/or plant exploration. New germplasm (accessions) enter NPGS through collection, donation by foreign cooperators, or international germplasm collections. An identifying number such as the Plant Introduction number is assigned to each accession.
2. Regeneration and evaluation of germplasm including dormancy, viability, and pathogen studies, when appropriate.
3. Pollination-controlled propagation in screened field cages utilizing a wide variety of pollinators; harvesting, drying, cleaning, picking and processing seed utilizing specialized seed equipment.
4. Long-term seed storage under controlled temperature/humidity conditions.
5. Seed imaging and germination testing.
6. International distribution.

Currently in its second year of operation and funded by both USDA/ARS and the National Institutes of Health, Office of Dietary Supplements, a collection specifically for medicinal taxa has recently been added to the NCRPIS.⁵ The current medicinal collection, focusing on three genera, Echinacea, Hypericum (St. John’s wort) and Actaea (black cohosh), has been utilized for a wide range of research projects, including but not limited to animal and human efficacy studies, analyses of metabolites of interest to the phytopharmaceutical industry, identification and synthesis of new compounds, ornamental and crop breeding, restoration ecology, and studies of population genetics.

Millennium Seed Bank scientist at work. Photo ©2007 Royal Botanical Gardens, Kew, United Kingdom

The development of new collections involves well-developed logistical planning. Fortunately, well-established collection protocols have been published, which address adequate representation of genetic variation for native plant collection.⁶ In order to efficiently prioritize future collection efforts for the medicinal collection, an extensive database (6,018 taxa) has been compiled from 29 international medicinal plant compendia. After analysis, a list of 4,209 taxa has been generated that are not included in the NPGS collections. These species will be prioritized by a variety of factors ranging from conservation status to economic use, resulting in a targeted list of priority species on which to focus future collection and acquisition effort. Future plans include significant expansion of the medicinal collection if appropriate funding is maintained.

A summary of the holdings of the NPGS, as accessed from the Germplasm Resources Information Network (GRIN) database in January 2006, includes 216 families; 1,916 genera; 11,850 species; and 476,101 accessions.⁷

Getting Involved

The best way to contribute to seed collection efforts worldwide is to support local botanical institutions. Visiting botanic gardens and arboreta and supporting them financially or as a volunteer is important to help strengthen conservation and horticultural aims. Joining a local native plant society may offer the opportunity to learn more about native plants through activities such as educational flora, native plant sales, and nature walks. At home, choosing natives for gardening, avoiding invasive species, and educating oneself on plant, pollinator, and wildlife interactions can help support healthy ecosystems.

Additionally, both of the aforementioned programs have Web sites and databases where one can check the collection status of various species. Holdings from the NPGS can be accessed on the GRIN Web site (www.ars-grin.gov/npgs). SOS also has a beautiful photo gallery available online (www.nps.gov/plants/sos/). Due to the highly technical skill involved in making SOS collections, privately collected seed samples are not accepted. However, many SOS institutions utilize their volunteer force to assist in collecting.

Botanical or phytomedicinal researchers may be interested in collaborative research and development of native plant materials. Most germplasm collection systems offer plant material to researchers and educators at little or no cost. The NPGS is interested in increasing the holdings of current collections and encourages anyone interested to contact them as they, like SOS, have very specific protocols to follow for collection of native species. They also encourage researchers to house their specimens with them for long-term storage and distribution once research has been completed in order to prevent degradation of samples. There have been far too many reported incidences of loss of valuable germplasm after research has been completed due to lack of proper storage conditions. Again, similarly to SOS, they collect voucher specimens for all new accessions along with passport data associated with their origins and precise details concerning propagation. Passport Data Collection includes but is not limited to global positioning system coordinates, county, state, directions to site, elevation, aspect, slope, soil type, habitat, plant associates, population size, photograph, and voucher specimen.

Genebanking is One Step in Conservation

Genebanking is an important ex situ (outside native habitat) conservation strategy that contributes to the dynamic process of maintaining and retaining native plant germplasm. But it is just one step in a larger conservation effort. Equally important are in situ (within native habitat) conservation, public education, propagation research, restoration activities, and other important activities that are critical to long-term conservation.

Megan Haidet is the communications coordinator for the Plant Conservation Alliance. Mary Byrne is the national collections data manager for the Seeds of Success program, coordinated within the Bureau of Land Management for the US branch of the Royal Botanic Garden, Kew’s Millennium Seed Bank. Joe-Ann McCoy, PhD, serves as the medicinal plant curator for the North Central Regional Plant Introduction Station.

References

1. Germplasm Resources Information Network page. Goddard Space Flight Center Web site. Available at: http://gcmd.nasa.gov/records/ GCMD_MSU0008.html. Accessed December 12, 2006.
2. Simple Answers to Basic Questions page. Global Crop Diversity Trust Web site. Available at: http://www.croptrust.org/documents/ Svalbard%20Q&A.pdf. Accessed December 19, 2006.
3. How is Diversity Conserved? Global Crop Diversity Trust Web site. Available at: http://www.croptrust.org/main/howis.php?itemid=124. Accessed December 7, 2006.
4. St. Clair B. Managing genetic resources: seed zones for native plant restoration. Presentation at 2006 PCA Meeting; November 8, 2006; Rosslyn, VA.
5. Brown AHD, Marshal DR. A basic sampling strategy: theory and practice. In: Guarino L, Ramanatha Rao V, Reid R, eds. Collecting Plant Genetic Diversity. Wallingford, Oxfordshire, UK: CABI Publishing; 1995.
6. Henry RJ, ed. Plant Conservation Genetics. New York: Haworth Press; 2006.
7. National Plant Germplasm Systems page. United States Department of Agriculture Agricultural Research Service Web site. Available at: http://www.ars-grin.gov/npgs/stats/summary.html. Accessed January 12, 2007.

Table 1: List of Acronyms

Seeds Under Siege

By Suzanne Edwards

Russian botanist Nikolai Ivanovich Vavilov (1887–1943) created a seed bank so large and diverse that his assistants risked their lives for its preservation during the siege of Leningrad in the final years of WWII in Russia. Vavilov is revered as a plant geographer extraordinaire and a pioneer in modern plant genetics. In 1921, Vavilov was appointed director of the Bureau of Applied Botany in Leningrad and expanded its mission to include major international seed-collecting expeditions, transforming the Bureau into a vast repository for seed and plant germplasm from around the world. Today, the Bureau is known as the N.I. Vavilov Scientific Research Institute of Plant Industry.¹

Beginning in 1941, the German siege of Leningrad lasted for 872 days. The Germans invaded Russia and captured Stalingrad but stopped short at Leningrad when they met fierce resistance. From that point on the Germans blockaded the city, isolating Leningrad from incoming food, water, and firewood. The people of Leningrad turned to eating their pets, pigeons, and lastly rats. Fourteen of Vavilov’s assistants stayed at the Vavilov Institute for the winter to protect the plants and seeds from pests, freezing weather, and starving people.² When the siege ended in 1944 a third of Leningrad’s population had died but the Germans were defeated and Vavilov’s seed bank endured.³

Those who travel to the Vavilov Institute 20 miles south of St. Petersburg (formerly known as Leningrad) will find a collection of more than 380,000 plants, including valuable genetic material belonging to plants found only in the former Soviet Union—25,000 of which are now extinct in the wild.¹

References

1.N.I. Vavilov Research Institute of Plant Industry historical review page [Web site]. Available at http://www.vir.nw.ru/history/history.htm. Accessed July 3, 2007.

2.Johnston B. Nicolay Ivanovich Vavilov: Plant Explorer Extraordinaire. HerbalGram. 1998;44:14-15.

3.BBC News “On This Day” page. BBC News archives Web site. Available at http://news.bbc.co.uk/onthisday/hi/dates/stories/january/27/ newsid_3498000/3498330.stm. Accessed July 2, 2007.

International Collection Efforts

The Millennium Seed Bank Project (MSB)

Goal: To collect and conserve 10% (over 24,000 species) of the world’s seed bearing flora by 2010.

History: A funding announcement was made in 1995 that monies raised by the British National Lottery would support the MSB Project.

Partners: The Royal Botanic Gardens, Kew Seed Conservation Department, and international partners in 18 different countries.

Funding: A £29.9 million contribution from the Millennium Commission, a distributor of the UK lottery.

Holdings: As of February 2006, the MSB held 14,098 identified species in cold storage. This amounts to 27 collections from 126 different countries.

Primary Activities: When seed collections arrive at the MSB they are cleaned, x-rayed, dried, packed, and stored. Germination monitoring studies then take place.

Interesting Fact: The MSB UK Program has already collected seed from over 94% of the UK’s higher plants.

Web site: http://www.kew.org/msbp/index.html

The Global Crop Diversity Trust and the Svalbard International Seed Vault

Mission: To ensure the conservation and availability of crop diversity for food security worldwide.

Goal: To raise $260 million endowment off of which the interest will support the genetic conservation of agricultural species.

History: The Trust was established in October 2004 as an independent international organization.

Partners: The United Nations Food and Agriculture Organization, Bioversity International, and Consultative Group for International Agricultural Research (CGIAR).

Funding: As of May 2007, more than $135 million had been pledged to fund the Trust. Donations have been contributed by the Bill and Melinda Gates Foundation, the company DuPont, various individual countries, and other organizations and corporations. The Norwegian government is funding the construction of the Seed Vault as a service to the world community.

Holdings: The Seed Vault will have a capacity of 3 million seed samples.

Primary Activities: The Trust is raising funds for its endowment while construction on the Arctic or Doomsday seed vault nears completion, expected September 2007.

Interesting Facts: The Vault is being dug into a mountainside north of the Arctic Circle, where permafrost will ensure that samples will remain frozen even if electricity fails.

Web site: http://www.croptrust.org/main/index.php

Bioversity International

Mission: To promote the greater well-being of people, particularly poor people in developing countries, by helping them to achieve food security, to improve their health and nutrition, to boost their incomes, and to conserve the natural resources on which they depend.

History: Established in 1974 as CGIAR, it was designed as an international plant genetic resources program. Forty-three countries have signed the IPGRI’s establishment agreement. In 2006, IPGRI and the International Network for the Improvement of Banana and Plantain (INIBAP) merged to form Bioversity International.

Funding: Primary funding comes from programs of the United Nations and various governments worldwide.

Partners: Global partnerships include CGIAR, System-wide Genetic Resources Program, the Global Crop Diversity Trust, the Global Facilitation Unit for Underutilized Species, and the Platform for Agrobiodiversity Research. National genebanks, public sector institutions, non-governmental organizations, and others also partner with Bioversity.

Holdings: CGIAR Centers alone maintain over 600,000 samples of crop, forage, and agroforestry species. Thus, the holdings of all Bioversity partners would likely reach into the millions.

Primary Activities: A wide variety of activities that contribute to the conservation of biodiversity.

Interesting Facts: The recent reorganization of IPGRI and INIBAP resulted in the creation of an entirely new word: “bioversity.” This term is intended to evoke feelings of the immensity of nature and the value of working together for the good of humanity.

Web site: http://www.bioversityinternational.org/