Purpose
To maintain in good condition and distribute seed of an extensive maize germplasm collection and of some of the crop's wild relatives in the Western Hemisphere.
Collections
Current CIMMYT maize accessions total more than 22,000 and new introductions are constantly being added from the cooperative regeneration project (see below). Passport data on CIMMYT maize germplasm bank accessions have been compiled and are available on CD-ROM. Similar data for accessions in national germplasm banks in Latin America and the Caribbean have been partially compiled for accessions evaluated under the Latin American Maize Evaluation Project (LAMP). To safeguard our collections, duplicate samples of about four-fifths are kept at the USDA National Seed Storage Laboratory (NSSL), Colorado, USA.
We classify our materials into two collections, base and active. Base collection seed is kept in sealed containers at subzero temperatures and low humidity, allowing it to remain viable for 50-100 years. Seed in the active collection is kept at just above freezing (0-2oC) and constitutes the "working" bank from which seed requests are filled. The current bank storage facility was built in 1972. We have begun construction of a new bank facility, with funding from the government of Japan.
To facilitate day-to-day bank activities, such as seed shipment, regeneration, characterization, and maintaining passport and seed storage information, we have an in-house database system developed in 1986-87. This is constantly updated. In addition, with help from CGNet and IPGRI, in 1989-91 we developed a PC-operated global database system that has been distributed worldwide to interested users.
Activities
We respond to requests for seed and information, distributing nearly 8,000 packets of seed a year and varied data on the seed we maintain and send. Our policy is to make the germplasm freely available to all clients so that useful diversity therein reaches as many maize farmers in the developing world as possible. All shipments are accompanied by proper phytosanitary documentation and every possible precaution is taken to ensure that seed is alive, healthy, and free of diseases and pests.
A significant function of a maize germplasm bank is to replenish seed samples when their germination falls below acceptable levels or their size is reduced by distribution. This can be accomplished either by collecting additional seed at the original site or by growing out viable seed from a sample, a process known as regeneration.
To enhance the utility of bank germplasm to maize breeders, we conduct extensive evaluations of Tuxpeño, Cónico, and other large race complexes. Based on the results, we then form core subsets that fairly represent the total genetic diversity of the race complex, but comprise much fewer accessions. The subsets are easier to manage and allow breeders and other researchers to locate more readily accessions of interest.
The Maize Program maintains seed of various taxa of teosinte and the genus Tripsacum. The latter wild relative is maintained in the field at one of our experiment stations in Mexico. In addition, we work with the national agricultural research programs of Guatemala and Mexico to monitor the status of their teosinte populations through periodic visits to the natural habitats of this maize wild relative.
As of late 1991, 14 national seed banks in Latin America and the Caribbean have been cooperating to regenerate endangered holdings of maize landraces in their collections. Coordinated by CIMMYT and financed by USAID (under Project Noah) and the NSSL, the rescue effort has restored seed of more than 3,000 endangered accessions and partially regenerated nearly 3,000 more. Back-ups of regenerated accessions will be kept at CIMMYT and NSSL. We are compiling data from cooperators on regenerated accessions, and will make this information available to all participants.
Policies and inter-institutional arrangements
Partly to ensure the unimpeded availability to researchers worldwide of genetic resources it conserves, the Consultative Group on International Agricultural Research (CGIAR, the system to which CIMMYT belongs) signed an agreement in 1994 with FAO that calls for the designation of specific accessions to be included in collections held in trust. Conditions of "in trust" storage specified in the agreement imply long-term storage and regeneration of holdings for the benefit of the international community. CIMMYT cannot store in trust any material which cannot subsequently be distributed under these terms, as specified in our materials transfer agreement, which insists on the free availability of the material for research and breeding and prohibits obtaining intellectual property rights on the material.
With regard to maize, all accessions except those defined as varieties have been designated as germplasm under the auspices of FAO and are considered to be held in trust. As stated in the CIMMYT germplasm acquisition agreement, all accessions currently being accepted for storage from institutions outside of CIMMYT will be held in trust. CIMMYT-developed germplasm being entered into the germplasm bank for storage will also be held in trust, except for varieties not deemed worthy of long-term storage.
CIMMYT and the USDA National Seed Storage Laboratory recently signed a memorandum of understanding that strengthens collaborative ties between the two institutions for the conservation of crop genetic resources. Duplicate samples of many maize accessions are preserved in the NSSL and in cooperating gene banks throughout Latin America and the Caribbean.
Finally, we are establishing collaborative ties with a series of emerging networks supported and coordinated by the Inter-American Institute for Agricultural Cooperation (IICA), Costa Rica, and dedicated to the conservation and use of plant genetic resources in the Americas.
For more information or seed, contact:
August, 2004
A Cost Study of Ex Situ Conservation