BP Singh

72 S.R. Bhatmanagement of germplasm conservation and exchange can beeffectively handled from a single window.Concurrent with developments in genetic engineering andcell genetic manipulation the range of material being exchangedhas also increased. Specialised cell lines giving high yields ofsecondary metabolites, genotypes with unique features are beingdeveloped and used in research and production. Tissue culture isindispensable in the exchange of such germplasm.Thus, the need for in vitro techniques in germplasm exchangeranges from desirable to essential. It is needless to emphasize thatadequate prior research is necessary to develop suitable protocolsfor in vitro culture and plantlet recovery in various crop species.General guidelines for in vitro exchange of germplasm1. Vegetatively propagated plants, as far as possible,should be exchanged through tissue culture.2. Use proliferating shoot cultures or rooted plantlets forexchange. (Avoid callus where stability is important).3. Cultures for exchange should be raised on semisolidmedium (agar or gelrite) and should not containcharcoal or antibiotics.4. In vitro cultures raised in plastic pouches or tubesshould be used for exchange.5. Only disease-free and certified germplasm should beexchanged.6. Information about media for proliferation and rooting,hardening procedures etc. should be provided whileexchanging germplasm in the form of in vitro cultures.7. Proper communication about shipment and expectedarrival time of material be ensured to avoid loss ofgermplasm.8. Proper labelling and directions for handling and storageof package during transit should be provided.