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An Open Access Journal published by ICRISAT
SAT eJournal ejournal.icrisat.org - 1 - December 2008 Volume 6
Plant genetic resources management: collection, characterization, conservation andutilization
HD Upadhyaya*, CLL Gowda and DVSSR Sastry
International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru 502 324, Andhra Pradesh, India
*Corresponding author: email@example.com
Genetic resources provide basic material for selectionand improvement through breeding to ensure foodsecurity needs of the worlds rapidly rising population.Conservation and utilization of plant genetic resourcesare important components of ex-situ collections.Management of ex-situ collections requires creative andadaptive decisions tailored to operating conditions thatare specific and continuously changing. The establishmentof large, crop-genepool-specific collections at ICRISAT(International Crops Research Institute for the Semi-AridTropics) genebank, Patancheru, India was based ondonations from existing collections and on targetedcollection efforts. Majority of the conserved accessionsare of orthodox seed producing nature. The conservedgermplasm has been characterized for important morpho-agronomic characters and germplasm seed samplesdistributed to bonafide researchers for utilization in cropimprovement programs all over the world. Exiguous useof germplasm has been observed in breeding programsmainly due to lack of information on economic traits.Core collections (10% of entire collection) and mini-corecollections (10% of the core or 1% of entire collection)have been developed to enhance the use of germplasm inbreeding programs. Core and mini-core collections havebeen used to identify genetically diverse trait-specificgermplasm with resistance to abiotic and biotic stressesand for agronomic traits. These will be used in breedingprograms to develop broad-based cultivars. This articledescribes the collections, genebank operations andpractices from conservation to utilization perspectives.
Plant genetic resources (PGR) are the most importantcomponents of agro-biodiversity. The PGR include primitiveforms of cultivated plant species and landraces, moderncultivars, obsolete cultivars, breeding lines and geneticstocks, weedy types and related wild species (IPGRI1993). Genetic diversity created in the farmers fields
over millennia, complemented by the diversity present inwild relatives of crops, provides the raw material forimproving crop productivity through plant breeding. ThePGR are finite and vulnerable to losses due to introductionof new crop varieties in agriculture, growing urbanization,natural hazards, etc. The PGR contribute enormouslytowards achieving the Millennium Development Goals offood security, poverty alleviation, environmental protectionand sustainable development. Over the years, genebankshave been established in a number of countries and thenumber of accessions conserved in about 1400 genebanksnow exceeds six million (FAO 1998). The mission of theConsultative Group on International Agricultural Research(CGIAR) is to achieve sustainable food security andreduce poverty in developing countries through researchand development in the fields of agriculture, forestry,fisheries, policy and environment. Exploration, exchangeand conservation of PGR is one of the main objectives ofthe CGIAR. The International Crops Research Institutefor the Semi-Arid Tropics (ICRISAT) (one of the 15 CGIARcenters) has responded to this need by establishing aGenetic Resources Unit for assembly, characterization,evaluation, maintenance, conservation, documentationand distribution of germplasm of sorghum (Sorghumbicolor), pearl millet (Pennisetum glaucum), chickpea (Cicerarietinum), pigeonpea (Cajanus cajan), groundnut (Arachishypogaea), finger millet (Eleusine coracana), foxtailmillet (Setaria italica), barnyard millet (Echinocloacrus-galli), kodo millet (Paspalum scrobiculatum), littlemillet (Panicum sumatrense) and proso millet (Panicummiliaceum).
Genetic variation, once considered unlimited, is fasteroding as modern cultivars replace traditional cultivarsover large areas, and natural habitats of wild relatives ofcultivated species are being destroyed. Several landracesof some of the above crops that are conserved in theICRISAT genebank at Patancheru, India have nowdisappeared from their natural habitats in Africa andAsia. Crop genetic diversity must be conserved to combatnew pests and diseases, and to produce better adaptedvarieties for the changing environments. Seed conservationhas vital role in preservation of genetic variability as it is
Citation: Upadhyaya HD, Gowda CLL and Sastry DVSSR. 2008. Plant genetic resources management: collection,characterization, conservation and utilization. Journal of SAT Agricultural Research 6.
SAT eJournal ejournal.icrisat.org - 2 - December 2008 Volume 6
An Open Access Journal published by ICRISAT
simple to handle, cost-effective and capable of maintaininggenetic stability over long time periods. Thus, seedconservation is a popular and most efficient tool forgermplasm conservation at the global level. There areseveral components in managing the PGR ex-situ; themost important among them are collection, characterization,conservation, distribution and utilization.
Germplasm assembly at ICRISAT
Assembly of germplasm through donation and exchangeis the primary approach of establishing a genebank.When ICRISAT was established in 1972, efforts weremade to assemble the germplasm of its mandate cropsthat existed with various research institutes in India andother countries. The Rockefeller Foundation had assembledover 16,000 sorghum germplasm accessions from majorsorghum areas, and ICRISAT acquired 11,961 accessionsin 1974 that existed in India and USA. ICRISAT alsoobtained 2000 accessions of pearl millet collected by theInstitut Francais de Recherch Scientifique pour leDveloppement en Coopration (formerly Office de laRecherch Scientifique et Technique d Outremer)(ORSTOM) in francophone West Africa. The germplasmof chickpea and pigeonpea originally collected andassembled by the former Regional Pulses ImprovementProject (RPIP), a joint project of the Indian AgriculturalResearch Institute (IARI), New Delhi; the United StatesDepartment of Agriculture (USDA); and Karaj AgriculturalUniversity, Iran, formed the initial collection. Sets of thisgermplasm, which were available in several agriculturalresearch institutes in India and Iran, and at USDA, weredonated to ICRISAT in 1973. ICRISAT also acquiredover 1,200 chickpea accessions from the Arid LandsAgricultural Development (ALAD) program in Lebanon.Similarly, much of the groundnut germplasm wasreceived from the Indian groundnut research program[now the National Research Centre for Groundnut (NRCG),Junagadh] and USDA. Besides germplasm donations bythe All India Coordinated Research Projects on variouscrops, considerable numbers of germplasm were receivedfrom agricultural universities at Pantnagar (Uttarakhand),Rajendranagar (Andhra Pradesh), Ludhiana (Punjab),Coimbatore (Tamil Nadu), Jabalpur (Madhya Pradesh),Rahuri (Maharashtra) and IARI at New Delhi.
Recently, we obtained chickpea germplasm samples:682 cultivated, 21 wild from the International Center forAgricultural Resarch in Dry Areas (ICARDA), Syria; and2083 cultivated, 68 wild from Washington StateUniversity, Pullman, USA. We also received from ourregional genebank in Niamey, 482 accessions of sorghumand 355 of pearl millet collected in Niger; and from
Nairobi, Kenya, over 200 pigeonpea accessions collectedfrom Mozambique, Tanzania and Uganda.
The national research programs in most countries,agricultural universities, regional research organizationsand the international agricultural research centers areengaged in developing crop cultivars/elite breeding lines.These collected lines are also conserved in ICRISATgenebank for future utilization.
Germplasm collections through explorations
The fundamental objective of collecting PGR is tocapture the maximum amount of genetic variation in thesmallest number of samples (Marshall and Brown 1975).The development of efficient strategies depends on theextent of available information on the type of geneticvariation in target taxa populations and their distributionin the target geographical region (Allard 1970). However,when there is lack of information on the target speciesand the collection area it might be prudent to organize anexploration mission to collect such information. Incollaboration with national programs, ICRISAT conductedover 200 expeditions to collect landraces, some of whichwere on the verge of extinction, challenging difficultterrain, hostile environments and harsh conditions.Details on each collection are recorded in the germplasmcollection data sheet (Appendix 1). The existing collectionsrepresent 7080% of the available diversity, and there iscontinuing need to rescue endangered germplasm.Analyses of diversity in the existing collections using GIS(geographic information systems) facilitate identification ofgaps to launch targeted collections. Germplasm collectionis expensive and a time consuming exercise. Therefore,we should review the past collections of the crop beforeembarking on a new collection trip. If others have alreadyexplored the area under consideration, we should try tosecure the germplasm from them. In some crops, for examplein pearl millet, which is a highly cross-pollinated crop,the early collections may have lost their genetic identitybecause of poor maintenance. Hence, fresh systematiccollection in such cases can be taken up (Harlan 1973).
Germplasm collection at ICRISAT
The ICRISAT genebank, Patancheru, India currentlyconserves 118,882 accessions of the five mandate cropsand six small millets from 144 countries (Table 1). This isone of the