| Wheat Germplasm Bank
Purpose To support global wheat improvement by maintaining collections of selected germplasm representative of all significant germplasm pools. Within the CGIAR, CIMMYT has responsibility for base collections of bread wheat and triticale, as well as back-up collections of spring durum wheat and wheat's wild relatives. Base collections of these two groups are maintained by the International Center for Agricultural Research in the Dry Areas (ICARDA). All these collections provide a reservoir of characters needed now and in the future to face the ever-changing requirements of plant breeding. Activities The Bank supports active breeding programs by assembling, characterizing, evaluating, and documenting wheat varieties, wild relatives, and genetic stocks. These materials, more than 90,000 accessions acquired over 50 years of breeding activities in Mexico, are available to bonafide scientific programs; priority is given to national programs in developing countries. About 15,000 samples are distributed annually. The Bank conserves, evaluates, regenerates, and documents materials. Accessions are stored at -2°, and should remain viable for up to 50 years. Longer term storage, at -18°, is under construction. In conjunction with IPGRI and gene banks of developing and developed countries, CIMMYT has, on occasion, participated in collecting materials from threatened areas and/or germplasm having unique characteristics. Other activities involve: Correctly identifying accessions. This is a vital element to the Bank's utility and efforts are being intensified to make sure an accession identified as a particular variety is indeed that variety. Inspecting all new accessions upon arrival and then, if found free of contamination, growing them in isolation. As for seed already in the Bank, studies are underway to isolate and identify microorganisms. Transferring traits (such as tolerances and resistances to biotic and abiotic stresses) found in Bank accessions to materials having better agronomic backgrounds, thus easing access to them and improving their utility to breeders (i.e. pre-breeding). Facilitating the search for traits by providing reliable information about individual accessions. For ease of access, we are building computer databases containing this information--called passport data--and other salient characters of materials in the Bank. These databases will be readily available to anyone involved in wheat germplasm improvement and will be an integral part of the International Wheat Information System (IWIS). Challenges Specific challenges of the Bank include: Reducing the effect of genetic drift, a consequence of natural selection and a constraint associated with seed multiplication and regeneration. To minimize this problem, seed is being regenerated only when necessary. Plans include accomplishing such regeneration only under controlled conditions in special screenhouses. Developing a system by which the global collection can be reduced to a more meaningful core collection without losing variability. Providing better communications and linkages among the wheat germplasm banks of the world so that through IWIS and GRIP (The Genetic Resources Information Package) all data can be accessed in a standard format. This will be vital to future progress. Transfer all germplasm bank materials and operations to the new joint maize/wheat gene bank when it is completed in 1996. Staff/Resources Currently, 1.0 person-year at the senior staff level is allocated to the Bank plus 1 associate scientist. Facilities include the Bank itself (built in 1982) with its cold storage rooms and processing area, land at six locations (3 hectares) within Mexico, adequate screenhouses, and an integrated computer network. For more information contact: © CIMMYT December 1996 |