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Biotechnological Application in Conservation
Dept. of Environmental Science
University of Kalyani, Nadia,
West Bengal
Prof. (Dr. ) S.C.Santra
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.
• Gene bank (DNA bank)• Seed banks,• Tissue culture bank,• Seedling banks.• Conservation strands,• Cryopreservation of ova, sperm or embryo
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:
Advantages and disadvantages of ex-situ conservation methodsConservation strategy Advantages Disadvantages
Seed Banks: - Propagules readily available for use,- Minimum work, little space is
required,- Provenance (clinical, geographical)
variation can be conserved provided species range adequately sampled.
- Recalcitrant seed can not be conserved,
- Large seed preservation is problematic
- Dose not conserve associated species.
Pollen Banks: - Minimum space required- Applicable for plants with
recalcitrant or orthodox seed
- Only half of the genome conserved,
- Tricellular pollen storage is problematic
Tissue Culture Banks:
- Minimum space required- Genetic erosion reduced- Short time required to produce
propagules
- Sometime sampling is problematic
- Problem some clonal variation
DNA Banks or Gene Banks:
- Minimum space is required,- Species with high extinction
potential can be conserved,- Applicable to all kinds of plants &
animals,
- Very costly to maintain the system
- Not a easy method, which required skilled persons.
Cryopreservation of ovum, sperm or embryo
- Minimum space is required,- All kinds of plants/animals
components can be preserved
- 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 , PhilippinesIRRI , PhilippinesIRRI , Philippines
02 Wheat - Cultivated species VIR Russia CNR, Italy
03 Maize - New World materials Asiatic materials
CIMMYT, MexicoNSSL, USA
04 Millets - Cultivated & Wild species Minor Millets
ICRISAI, IndiaNSSL, USAICAR, India
05 Oats - Cultivated & wild Species PGR, Cnada
06 Sugarcane - Cultivated ICAR, IndiaNPGS, USA
07 Potato - Wild & cultivated species CIP, PeruAVRDC, 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.
• 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 and landraces of traditional agricultures,
• Wild and weedy taxa, near relatives of crop plants,
• Special genetic stocks, including induced mutants.
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.
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.