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.

Thank You