Crop Genetic Resources

whooshdisguisingBiotechnology

Dec 14, 2012 (4 years and 8 months ago)

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Crop Genetic Resources



Biological resources include the genetic
resources used to produce agricultural crops.


The relationship between agricultural production
and biological resources is two directional:


Agricultural production may negatively affect wild
biological resources


Agr. Prod. also depends on crop and livestock
genetic resources, some of which are found in
the wild.


Therefore, conservation of crop genetic
resources is needed.


Agriculture's Dependence on
Genetic Resources



Agriculture and genetic resources are
critically interdependent. All agricultural
commodities, even modern varieties,
descend from wild genetic resources from
around the world.


Agricultural production depends on
continuing infusions of genetic resources
for yield stability and growth


The relationship between genetic resources and agriculture



Before the development of modern varieties,
farmers cultivated
landraces


Landraces are varieties of crops that evolved
and were improved by farmers over many
generations, without the use of modern breeding
techniques.


These varieties are generally very diverse within
species, because each was adapted to a
specific environment.


The pace of improvement accelerated as
modern breeding techniques

were developed
that facilitated selection of specific desirable
traits.



Desirable traits, such as high yield, quality,
and others have resulted from the use of
genetic resources.


Breeders have also sought resistance to
pests and diseases, and tolerance to non
-
biological stresses, such as drought.


So this creates a constant demand for
genetic resources.



The advent of
biotechnology

and
genetic
engineering

may increase the demand for
genetic resources.


The use of genetic engineering may make
it easier to incorporate the beneficial
characteristics of landraces, and wild
relatives of agricultural crops.


Genetic engineering also can be used to
incorporate traits from other species (GM)


On the frontier of biotechnology research
are efforts to increase the genetic material
that breeders can access.


Organisms may carry within their DNA
many genes that are not expressed as
traits, some of which are of interest to
breeders.


In the future, scientists may be able to
determine how these unexpressed genes
operate, and make use of them in the
breeding of new varieties.

Economic Value of Genetic
Resources



Attaching a value to genetic resources is a
complex task.


The simplest value arises from the “direct
use” of genetic resources.


Direct use values include the use of
genetic resources to produce food and
fiber, or to help create new varieties of
crops and livestock.


Lebanon is Rich in Genetic
Resources


A natural wealth


More species than England, France, Syria,
Egypt, Jordan, Cyprus……


Genetic resources are being lost.


Conserved genetic resources may also
have economic value even if the resources
are not currently being used.


The option to exploit resources in the
future, for uses not presently known, has
considerable value, though this value is
difficult to measure.


For example, humans presently make little
use of many resources found in tropical
rainforests.


May become important for agricultural or
pharmaceutical applications.


The
information

about a conserved
resource has economic worth.


"
Genomics
" refers to investigations into
the structure and function of very large
numbers of genes undertaken in
simultaneous fashion.


Many activities may be classified as
genomics research, including:




Mapping and sequencing the genome of
an organism;


Studying genetic variability within species;


Studying genetic similarities across
species;


Discovering gene function, and the
relationship between gene structure,
protein synthesis, and metabolic
pathways;


Studying gene regulation and interaction

Measurement of the Benefits of
Genetic Resources


Brennan,
et al
. (1997) determined that 64 % of
the improvements in Australian rice came from
international germplasm.


OTA (1987) estimated that genetic
improvements have accounted for half the yield
gains in major cereal crops since the 1930's.


Thirtle (1999) concluded that biological
improvements contributed up to to 50 % of the
yield growth of corn, 85 % for soybeans, 75 %
for wheat, and 24 % for cotton.

Benefits from Genetic
Improvements


Access to Genetic Resources and
Benefit
-
sharing



One of the objectives of the Convention on
Biological Diversity is the "fair and
equitable sharing of the benefits arising
out of the utilization of genetic resources”.


Since no nation has within its borders the
desired spectrum of genetic resources,
international collection and exchange
occurs.


Not all participants in this exchange,
however, view the benefits as fairly
balanced between donors and recipients.


Another issue is that valuable genetic
resources not yet collected and preserved
may be endangered by land use changes
in some countries.


To address these issues, delegates from
116 countries voted in November 2001 to
adopt the text of a new

United Nations International Treaty on Plant
Genetic Resources for Food and
Agriculture


The new treaty has several
objectives


Mandates the conservation and sustainable use
of plant genetic resources for food and
agriculture.


Seeks fair and equitable sharing of benefits
arising out of the use of these resources.


Establishes a multilateral system to facilitate
access to all crops listed in Annexes I and II of
the treaty and to share the benefits derived from
such facilitated access.

Who benefits from the Treaty
and how?



Farmers and their communities, through Farmers' Rights


Consumers, because of a greater variety of foods, and of
agriculture products, as well as increased food security


The scientific community


International Agricultural Research Centres, whose
collections the Treaty puts on a safe and long
-
term legal
footing


Both the public and private sectors


The environment, and future generations, because the
Treaty will help conserve the genetic diversity necessary
to face unpredictable environmental changes, and future
human needs.

Genetic Diversity



The loss of genetic diversity in a species,
also called
genetic erosion
, has been
identified in many commercially important
crops.



The loss of wild relatives occurs mainly
through
habitat conversion
.


Genetic erosion of crop varieties can be
furthered as
landraces

are displaced by
commercially developed modern varieties.


When choosing varieties, farmers consider
yield potential and consumption attributes.


Sometimes landraces offer superior yields
and consumption traits, but often they do
not.



Southeast Asia
-

coconut, rice, sugarcane


China
-

Chinese cabbages, soybean


India
-

cucumbers, eggplant, pigeonpea


Turkey
-
Iran
-

wheat, barley, oats, figs


Mediterranean
-

almonds, cabbage, olives


Mexico/Central America
-

maize, tomato


Andes/Brazil/Paraguay
-

peppers, potato,
rubber