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Biotechnological Application in Conservation Prof. (Dr. ) S.C.Santra Dept. of Environmental Science University of Kalyani, Nadia, West Bengal Modern biotechnology began with the first recombinant DNA experiment in 1973. But its real application started after 1980, when the U.S. Supreme Court held that a genetically engineered microorganism was patentable, then biotechnological companies formed to commercialize recombinant DNA technology. • In recent decades, a multicentric project on bioprospecting of biological wealth using biotechnological tools has been launched in various countries. The overall objective is of characterization, inventorization and conservation of biodiversity of different ecogeographical regions and prospecting of nenes and biomecules. • Economically and medicinally important species are being prospected for genes and bioactive molecules of therapeutic and agricultural importance, conservation strategies are being worked out depending on the species richness. • Economically important elite varieties have been identifical and the fingerprinting is being done to compare accession/collection from different geographical locations. • This is helping in developing conservation strategies, especially for the endangered species. Geneprospecting studies have also been successful and today nearly 25 stress tolerant genes from identified, characterized and cloned. Studies are also ongoing for transfersing these genes to other economically important crop plants. Biotechnology in ex-situ conservation Ex-situ (away from the habitats or sites) conservation method of Biodiversity and Wild life Protection is seldom sufficient process. Almost any species could be preserved ex-situ if enough money were devoted to it, but in practice it is usually high quality species or races, such as relatives of crops, domestic animals and charismatic species which are protected in this way. In general ex-situ methods have proved a very valuable complement to in-situ methods and a number of species would not have survived without the synergy between the two. Collection of species and races for ex-situ conservation has now become a race against time and a range of methods have been developed to collect pure strains, avoid hybridization, and minimize impacts on wild populations. There are a number of ex-situ conservation practices as adopted over the time mentioned as follows: • • • • • • Gene bank (DNA bank) Seed banks, Tissue culture bank, Seedling banks. Conservation strands, Cryopreservation of ova, sperm or embryo Advantages and disadvantages of ex-situ conservation methods Conservation strategy Advantages Disadvantages - Propagules readily available for use, Minimum work, little space is required, Provenance (clinical, geographical) variation can be conserved provided species range adequately sampled. - Minimum space required Applicable for plants with recalcitrant or orthodox seed - - Minimum space required Genetic erosion reduced Short time required to produce propagules - - Minimum space is required, Species with high extinction potential can be conserved, Applicable to all kinds of plants & animals, - Minimum space is required, All kinds of plants/animals components can be preserved - Seed Banks: - Pollen Banks: Tissue Culture Banks: DNA Banks or Gene Banks: - Cryopreservation of ovum, sperm or embryo - - - - - - Recalcitrant seed can not be conserved, Large seed preservation is problematic Dose not conserve associated species. Only half of the genome conserved, Tricellular pollen storage is problematic Sometime sampling is problematic Problem some clonal variation Very costly to maintain the system Not a easy method, which required skilled persons. Involves freezing, with liquid nitrogen, very costly method Viability of healthy clone is sometime questionable Ex-situ conservation technology Sl. No. Methods Purpose Examples 1. Embryo micropropogation Increasing population Orchids and many other plants 2. Somatic embryogenesis Do Bamboo, cycads and others 3. Clonal propagation of shoot tips Do Ornamental plants, 4. Artificial insemination Do Tiger, Giant Panda 5. Embryo axis cryopreservation Storage of recal eitrant species Quereus sp. (Oak) 6. Cryopreservation of cell suspession Do Orchids 7. Storage of seeds in moist substrate Breaking dormancy Several plant species 8. Cryopreservation of sperm, ovum, embryo of animals Storage of germ plasm Several wild animals 9. Seed storage at low temperature (-21°C) Imposing dormancy Several crop seeds Preservation of plants or seed in genebanks or in vitro cell lines or cloned in tissue collections under appropriate conditions or longterm storage often seems to be the easiest and most preferred mode. Genebank collections and in fact many breeders collections are too large for scientist to intensively investigate and record all traits in the sereening process. Net work of Gene banks of some crops Sl. No. Crops Locations 01 Rice - Oryza sativa oryza indica Wild rice species IRRI , Philippines IRRI , Philippines IRRI , Philippines 02 Wheat - Cultivated species VIR Russia CNR, Italy 03 Maize - New World materials Asiatic materials CIMMYT, Mexico NSSL, USA 04 Millets - Cultivated & Wild species Minor Millets ICRISAI, India NSSL, USA ICAR, India 05 Oats - Cultivated & wild Species PGR, Cnada 06 Sugarcane - Cultivated ICAR, India NPGS, USA 07 Potato - Wild & cultivated species CIP, Peru AVRDC, Taiwan 08 Groundnut - Cultivated species ICRISAT, India 09 Soabean - Cultivated species CIAT, USA 10 Phaseolus - Cultivated species German Seed bank Threats to Germplasm of crop plants & its conservation need A technological fact of improved varieties is that they have a tendency to eliminate the resource that they are based on and from which they have been derived by breeding. Current elite varieties yield better than the varieties they displace, and once a displaced variety is no longer planted, its genes are lost to future generations unless it is conserved. The gene rich ancestral forms are lost because of bad land use planning, environmental degradation and urbanization. The wholesale loss of plant genetic resources is called genetic erosion. It is a slow and gradual process. In the developing world, high yielding varieties (HYV) for the major crop have come into dominance just within the past three – four decades. The traditional local germplasm is wiped out and genetic vulnerability could be seed as consequent events. Thus germplasm conservation became a top priority today in agriculture. A better understanding of gene banks requires an appreciation of the kinds of genetic materials that can be saved as seed. Germplasm can be organized into five distinct categories. • Varieties of cultivars in current use, often elite varieties; • Obsolete cultivars, Often the elite varieties of 20 to 50 years ago and usually formed in the parcentage of current cultivers; • Primitive cultivers agricultures, • Wild and weedy taxa, near relatives of crop plants, • Special genetic stocks, including induced mutants. and landraces of traditional Inbreeding depression of wildlife and need for germplasm conservation Inbreeding depression is a decline in viability and /or fecundity of indiriduals resulting from mating between close relatives. Inbreeding is minimized in an idealized population, in which individuals mate randomly. However populations may depact from this giving a low genetic variations. If deleterious recessive alleles become homozygons, pathological conditions result. Wild populations are seldom sufficiently well known to withness inbreed depression and this showed high rate of, mortality in their natural habitats. Germplasm conservation of such population is highly essential. Some examples of the consequence of inbreeding depression of wild animals Sl. No. Animals - Consequences 01 Cheetah (Captive population) - Low sperm concentration high vulnerability to infection; 02 Florida panther - Low sperm quality vulnerable to microbial parasites 03 Siberian tiger (Captive population) - Decreased fertility & viability to zoo 04 Golden lion tamarin - Increased juvenile mortality 05 Common shrend - Decreased fertility 06 Song sparrow - Reduced survibility Thus use of biotechnology tools is conservation practices are very much essential today, through there are some adverse impacts of biotechnology on biodiversity specially with respect to non-target effects of GMO in natural ecosystem. Raises the questions of biosafety issues and also disstatrilization of dynamicity of natural ecosystem. Thank You