| IV. Specific considerations related to management of genentic reosurces A. National collections should continuously replace the missing accessions with stock from the base collection at IRRI and vice versa B. Procedures and guidelines should be developed for collecting and cataloguing of minor variants such as ecostrains, induced mutants, and other genetic manipulations of varieties. C. Participants recommend that germplasm conservationists at some locations try to "trap" genes from closely related wild species (for example, by growing domesticated and wild types in close proximity to take advantage of the natural crossing). D. Countries that plan to initiate rice breeding programs may need a minimum working collection. The International Rice Observation Nursery of the International Rice Testing Program will provide widely divergent varieties and information to fulfill this need. E. For the identification and avoidance of duplciates, observations on biochemical characters and root characters may be included in addition to the conventional agro-morphological characters currently taken on each accession. F. Realizing that geographic environments differentially affect field performance and agronomic characters of varieties, stored data on such characters should include the date and location where such data were taken. G. Participants urge countries that lack adequate facilities for medium-term seed storage to send duplciate samples of all accessions in their collections to IRRI for safe storage. National programs should give high priority to the establishment of facilities for medium-term storage. H: Participants recognzie that variation may exist within a collected sample or population. In order to fully utilize such material, it is suggested that the original sample designation should retain as part of the continuing identification in any division of the sample according to type. I. Apparent off-types within named varieties should be retained in the collections - not discarded - unless they are obviously mechanical mixtures. Otherwise they should be designated as subsamples of the original accessions. When seedstocks are rejuvenated, the same care should be taken to not rogue out variants in the original sample and thus lose potentially valuable genes forever. J. Morphologic and other economic traits recorded in the data systems of the germ plasm centers should be expanded periodically to include data collected at other locations. Also the inclusion of additional characteristics in the data system may be desirable. K. The participants recommend further standardization of terminology used in collection, preservation, and utilization of germ plasm. L. Recognizing the frequent changes in taxonomic nomenclature, the participants recommend that synonyms be identified in all rice collection catalogues. M. The participants stressed the importance of having continuity in personnel experienced in germ plasm conservation and in accurate record keeping for the proper maintenance, evaluation, and utilization of rice germ plasm. N. Participants recognize an urgent need to collect germfls plasm of wild and weed races of rice. To properly carry out such collection activities, specialized training conducted in the locality of the materials is highly desirable. O. Participants expressed the desirability of adequate training of workers for field collection, maintenance, storage, and utilization of valuable germ plasm. |
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