BP Singh

The Indian National Gene Bank 245Indian National Gene BankThis national facility for long term ex situ conservation of basecollections, set up by NBPGR at New Delhi, has four majorcomponents:(i) Seed Repository : Samples of orthodox type seeds aredehydrated at 15°C and 15% RH to around 5% moisture content,sealed in laminated aluminium foils under vaccum and depositedin cold storage at -20°C.(ii) Tissue Culture Repository : Disease-free tissue cultures ofrecalcitrant seeds (those not capable of withstanding dehydrationand very low temprature) and vegetatively propagated plantspecies, developed from meristem explants r are maintained usingappropriate growth-limiting media and by subculturing at suitableintervals.(iii) Cryopreservation Facility: Seed samples of selected speciesI synthetic seeds' embroys and gametes are being preserved usingcryopreservation technique, either by immersion in liqUid nitrogen(-196 D C) or by keeping in its vapour phase (around -150°C)following protocols using computerised freezing-thawing ratesand chemical cryoprotectants.(iv) Clonal Repository: Germplasm collections of vegetativelypropagated crops like turmeric, ginger, sweet potato and bananaare being maintained under field conditions following suitablecrop rotations and backed by tissue-culture s~fety duplication.Priorities of the,Gene BankThe Indian Gene Bank serves as the national facility for longterm conservation of genetic resources of cultivated plants, andtheir wild relatives and also species of economic importance.Priorities include landraces, locally adapted traditional cultivars offarmers, primitive and old varieties, prized genetic stocks and wildand weedy relatives of cultivated plants. Seed samples of allimproved crop varieties released at the national level for commercialproduction as well as of the varieties granted protection are alsokept as reference materials. The Indian Gene Bank has alsoaccepted global responsibility for providing safety duplication ofgermplasm holdings of several crops on behalf of lARes underterms set out in memoranda of understanding.