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Chapter
54
Conservation
and
Use
of
Plant
Genetic
Resources
54-1 PROTECTING THE GENETIC
LmRARY
Comprehensive protection
of
genetic resources must be
implemented in response to scientific strategies based on our
increasing understanding
of
the complexity
of
species biol-
ogy. Without sound scientific approaches to conservation,
organizational strategies will fall short
of
ensuring the protec-
tion
of
the very species they were established to protect.
Sound scientific strategies are needed to guide conservation
efforts from germplasm acquisition to management
of
collec-
tions
at
the national and international levels. This will neces-
sitate integrated approaches to comprehensively protect the
genetic library represented by global plant genetic resources,
including greater interaction between scientists working at
the three levels
of
biological diversity: genetic, species, and
ecosystem.
Of
the three levels which comprise global biological
diversity, genetic diversity has received the greatest attention
within the agricultural community. Genetic diversity refers to
the total genetic information contained in individual plants
of
a species, each containing a unique assembly
of
genes consti-
tuting its evolutionary heritage. This diversity begins at the
molecular level, is carried as sequences
of
instructions on
chromosomes, and provides a foundation for environmental
adaptation and ultimately for the evolution
of
species.
This focus on genetic diversity and its application to
modem crop improvement allows for manipulation
of
ge-
netic diversity within time (Duvick, 1984). However, a focus
on genetic diversity and ex situ collections alone is not
adequate for the needs
of
global agriculture. For conservation
of
genetic resources to maintain its relevancy, greater under-
standing
of
the remaining two elements
of
global biodiversity,
that
of
species and ecosystem diversity, will be needed. These
components offer the potential for diversity in place as
opposed to time.
423
J.T.
Williams
IFAR
Arlington
Virginia
Joel
I.
Cohen
International Service for
National Agricultural Research
The
Hague, the Netherlands
The need for integrated conservation strategies can lead to
confusion regarding the types
of
conservation approaches
available, largely because the
term'
genebank' has come to be
equated with the refrigerated seed store. Ex situ samples may
be conserved as seed, cultured cells or tissue, or growing
plants. In situ may involve a target species as a component
of
an ecosystem without genetic management or a specific
genetic reserve with management intervention.
Integrated conservation considers a range
of
conservation
resources and methods for use, depending on the type
of
genepool, or biological entity
of
concern (Falk, 1990). In the
case
of
crop plants, which have immediate utility, most are
amenable to seed storage. Some require complementary in
vitro conservation, and with others, orchards are used as field
genebanks. Not all are suitable for long-term storage.
An additional responsibility rests with the international
community to ensure that national programs relate to interna-
tional interests based on commodities. Collections main-
tained by commodity-based International Agricultural Re-
search Centers (lARCs) represent the latter, whereas national
collections represent a spectrum
of
diverse activities related
variously to plant introduction, local conservation, and plant
breeding. Some are large, integrated, mUlti-crop programs,
e.g., in India, China, Brazil, Russia, and USA; others are
related to very few crops; and others are solely collections
of
plant introductions. The Food and Agriculture Organization
of
the United Nations (F AO) Commission on Plant Genetic
Resources presents one means to re-frame national program
aims, assure operating funds, and provide global linkages.
Many programs will be viable into the future; others may
fail, so the security
of
collections, long a strategic aim
of
the
International Board for Plant Genetic Resources (lBPGR)
Printed in International Crop Science
I.
1993. Crop Science Society of
America, 677 S. Segoe
Rd
..
Madison, WI 53711, USA.
Published 1993
424
will become vitally important. Storage facilities will be
transformed into real genebanks, fully functioning with nec-
essary regeneration, documentation, and evaluation proce-
dures in place. Many programs are operating at functional
capabilities and are unable to systematically meet user de-
mand. This illustrates a major gap in the international sys-
tem.
Investment
should
not
be
in
many
more
genebanks
but
in
their
management and efficiency. Nor should this
central theme
be
diluted by spending more on creating public
awareness
or
in schemes for on-farm conservation
of
prim i-
tive forms until there is indeed global security
of
the staple
food-crop germplasm and representative collections
of
other
plants.
54-2
MOVING TOWARDS
CONSERVATION COLLECTIONS
A more integrated approach to conservation which en-
courages the inter-relation
of
systems mentioned above would
allow a more comprehensive conservation program to emerge.
In so doing, ex situ collections become conservation collec-
tions, defined as collections comprising representative ge-
netic samples
of
species according to the best available
scientific understanding
of
the species' population biology.
They are maintained in one
or
more forms (such as growing
plants, seeds, and tissue culture) and curated for permanent
maintenance (Center for Plant Conservation, 1991). Adop-
tion
of
collection and management guidelines will be neces-
sary in updating ex situ collections to conservation collec-
tions and to ensure their emergence into an international
system that takes advantage
of
multiple conservation meth-
ods. Present tasks include:
1. Sort out collections which conserve materials already
well conserved and duplicated elsewhere, remove redun-
dancy.
2.
Make collections more representative
of
the patterns
of
genetic diversity in the crop genepools.
3. Provide better scientific standards and guidelines for all
aspects
of
collection management.
4. Develop management guidelines for strategic planning,
funding allocation, and cooperation with other programs.
These all rely
on
good documentation systems integrated
across programs and based
on
individual commodities. For
instance, sorting out
of
samples can
be
done when it is known
who stores what, and redundancies can
be
identified. Site
collection data and characterization data enable unique mate-
rials to be identified, provide knowledge
of
where unique
landraces
or
primitive cultivars originated so that they can be
conserved in the right areas in relation to grow-outs, and
facilitate decisions on what should justifiably be conserved
by whom.
Making the collections more representative means analyz-
ing patterns
of
ecogeographic differentiation, identifying
related species that comprise crop genepools, ensuring that
90%
of
the effort is not being targeted to save only 10%
of
the
known diversity, and planning for additional exploration and
collecting to amplify collections while avoiding duplication
WILLIAMS & COHEN
of
effort. Genetic erosion will not wait for approval
of
pend-
ing international agreements
or
networking arrangements.
Action needs to be spurred by scientists, as it was in the
past, because comparatively little is known
of
genepool
representation
or
distribution in many cases, and only scien-
tists can give the best-informed opinion. We believe that
emergency action plans should be formulated for major
commodities, to be completed in a five-year period. Each
should have elements
of
collecting, integrated database de-
velopment, and secure storage and description. They would
address filling gaps identified in the early 1980s (Williams,
1984) and some that still remain today (Williams, 1991).
Such action plans could take into account the numbers
of
samples estimated to be required by the World Resources
Institute (WRI, 1992) for crop genepools, forest species,
medicinal plants, ecosystem rehabilitation, and traditional
underexploited plants. Many existing institutional operations
could be "signed up" for this endeavor with some re-alloca-
tionoffunding.Atleastbytheendofthedecadeofbiodiversity
these action plans would have accomplished much for true
conservation collections despite a degree
of
guesswork.
They would be seen as insurance policies and would
properly complement other activities such as in situ conser-
vation
of
ecosystems. At the same time, a major gap could be
addressed: how to integrate ex situ activities with in situ
programs. Leadership is desperately needed to provide di-
verse guidelines for genetic management
of
populations in
situ and cross-indexing databases
of
protected area invento-
ries with
ex
situ integrated databases. For example, as many
as 200 crop species originated in tropical and subtropical
forests, and many still have wild populations there (Smith et
al., 1992), but no detailed databases provide information for
either conservationists or crop enhancers. The availability
of
emergency action plans would make it easier for national
programs to identify their own roles and for the strategically-
determined national plan
of
action (Cohen et al., 1991) to be
justified
in
terms
of
the inter-dependency
of
nations on plant
resources.
54-3
VALUING INVESTMENTS
IN GENETIC RESOURCES
Conservation
of
resources is a multi-institutional, multi-
component effort. Funds required to effectively and effi-
ciently preserve genetic resources for future generations have
not been properl y estimated nor provided for required conser-
vation efforts, as exemplified by the U.S. National Plant
Germplasm System (NAS, 1991).
What are potential sources
of
funding for conservation
of
genebank -based genetic resources? Tax -based revenues sup-
porting conservation represent a major portion
of
available
funds. However, general deficiencies in this sector, coupled
with a lack oflong-term investment strategies, is a recognized
problem (Mares, 1986). In the USA, approximately 2%
of
the
national budget ($14 billion in 1983) was allocated to domes-
tic natural resources and environment programs. Because
of
weak economies in many developing countries, an equivalent
expenditure is virtually impossible. Contributions by the
USE
OF
PLANT GENETIC RESOURCES
USA
in
1989 for conservation
of
diversity abroad were $62.9
million, yet countries receiving larger portions of these funds
still lacked resources to curb the loss
of
biodiversity
(Abramovitz, 1991).
Greater support must be obtained for conservation-level
investments
to
increase returns derived through use of ge-
netic resources. Without such investment, and recognition of
the value
of
this investment, resources will remain untapped,
as
if
sealed in a vault or be used without recognition, credit,
or documentation provided to the relevant conservation pro-
gram, or, be exploited in a nonsustainable manner.
In
effect, ex situ programs may compete with one another
for clients
as
users discover which program is most able
to
provide reliable services. Many user groups, both public and
private,
are
in
need
of
high-quality , well-characterized samples
of conserved accessions. Thus, a potential source of income
is
being missed because genebanks are often not able
to
effectively conserve, characterize, and ensure viability of
accessions. Over time, users will pay careful attention
to
the
quality of service provided by each conservation program.
Certainly, there can be little claim
to
fees for dead or inviable
seed samples or for accessions that cannot be found due
to
inaccurate inventories, and that are infested with pathogens,
and
are
poorly characterized. It is also a concern when no
forethought is given to the potefltial worth of such material
by
the host country institution.
On
the contrary, when services, accessions, and data
provided by the genebank are determined
to
be
of
good
quality, this should be acknowledged
as
a "value-added"
feature following the original acquisition, rather than being
taken for granted. This will be true whether the sample
was
acquired
by
collection, exchange, or is indigenous or exotic.
Added value comes from attributes applied
to
accessions
incorporated into genebanks. Such value is desperately needed
within national and international ex situ and
in
situ collec-
tions of plant germplasm. However,
to
what extent can these
activities be undertaken when financial resources are limited
to
the most basic aspects
of
conservation or preservation?
Managers
of
ex situ centers
of
diversity must be able
to
effectively interact with legal, scientific, and commercial
partners to help enhance the value
of
their collections. For
example, agreements may be developed
to
ascertain the range
of molecular diversity for certain traits among accessions of
a particular species. The number of viable, unique samples
in
a collection increases the range of diversity that could be
sampled. Financial arrangements would be needed
to
supply
the samples, develop the molecular analysis, and finally,
to
determine how results and the most promiSing germ plasm
would be handled.
S4-4 HUMAN RESOURCE DEVELOPMENT
AND RESOURCE CONSERVATION
Development and expansion
of
crop genetic resource
programs over the past decade have demonstrated the need
for
relevant training. Well-functioning genebanks require
strong programs that link variation stored in conservation
collections with crop improvement (Goodman, 1990).
425
Genebanks
in
developing countries can more effectively
contribute
to
improving agronomic productivity
when
sup-
ported by concurrent increases in plant breeding and
in
the
development of seed industries to produce elite seed.
When training for plant genetic resources
was
initiated
in
the United Kingdom, with the moral support of F
AO
in
1969
and strong support from IBPGR after 1975, this provided
the
emerging genebank system with scientists trained
in
all
the
multi-diSCiplinary aspects of genetic resources. This
was
supplemented with numerous short courses organized
by
IBPGR, other IARCs, and some national programs.
How-
ever, the volume of people trained has fallen short
of
the
needs.
A review of the U.S. National Plant Germplasm System
(NAS, 1991) suggested the need
to
develop a significant
international extension to its existing domestic mandate.
Also more "hands-on" internships at Universities and Cen-
ters are needed (Cohen et al., 1991).
As
genetic resource programs expand their scientific
and
technical base, and define their relation with other conserva-
tion efforts, new needs
in
conservation management emerge.
To address these needs and
to
form more integrated conser-
vation efforts, germplasm practitioners must apply disci-
plines
as
diverse
as
population genetics, demography, field
collecting, seed storage, propagation, tissue culture, and
various maintenance strategies. New educational opportuni-
ties, such
as
the Summer Institute for Genetic Resource
Conservation, provide key opportunities
to
explore these
diverse topics and acquaint germplasm professionals
with
their inter-relationships (McGuire, 1991).
The needs of both the genetic-resources workers and
the
user community are pertinent issues. First, the requirements
of managers of genetic resources programs are changing.
Whereas 20 yr ago, their work was largely for conservation
as
a service function
to
breeding-if
it
existed-they
now
need
to
interact with nature conservation for conservation of
biodiversity, with forestry genetic resources requirements,
and others. Strategic national planning
is
required
as
well
linking global activities
on
any
specific crop genepool (Cohen
et
aI.,
1991).
Second, the number of plant breeding graduate students
is
declining in parallel with the upsurge of interest
in
biotech-
nology. Aside from the prebreeding or enhancement that
can
utilize genes
in
primitive and wild materials, the more tradi-
tional breeding requires a
5-
to
15-yr development period.
Broader genetic enhancement programs will maximize
and
justify the use of germplasm collections.
Once
implemented
in
a country, the use of modem crop cultivars can only
be
sustained through a well-planned plant breeding program and
clear strategy
by
the genebank manager and breeders. The
need for sustainability should not detract from this; there will
be no return
to
peasant agriculture except
in
marginal areas
where it
is
possibly more environmentally sound. Plant breed-
ing aims might move somewhat from total use of monocul-
tures
to
more consideration
of
cultivar mixtures and inter-
cropping systems. This will require regional cooperation,
and
genebank managers must develop new skills
to
avoid
the
problems
of
many past regional programs. The following
educational programs will be required
to
meet their needs:
426
1. Training
of
genebank personnel
to
strategically manage
collections.
2. Educating conservation biologists to recognize the needs
of
their colleagues dealing with genetic resources, and
for a certain number to be fully trained in curating and
managing genetic reserves as parts
of
the broader ecosys-
tem conservation and in conserving threatened species
ex situ.
3. Preparing biodiversity scientists to recognize the urgent
applied aspects so that crop, forest
or
forage genepools
can be described in terms
of
patterns
of
variation using
modem molecular and biochemical methods, and for
research to be strategic and applied rather than basic.
4. Training managers in research planning, monitoring,
and development
of
fully collaborative programs to
maximize cost-effectiveness and efficiency. Curators
must become much more pro-active to address these
needs (Williams, 1985); they should collectively deter-
mine how worldwide cooperation and collaboration in
germplasm availability and use develop. There are im-
portant messages here for the Consultative Group on
International Agricultural Research (CGIAR) as it moves
to policies in this area and networking on specific crop
germplasm through IBPGR.
The training needs above are not being addressed fully,
and there does not appear to be a clear policy agreed upon by
all the international organizations involved. The
job
of
re-
source manager begins where that
of
a policy maker leaves
off
(Orians
et
al., 1990) but synergies between the two are
necessary to make technology effective, to cope with uncer-
tainty, and to choose and manage existing technologies.
Training in this area is still virtually non-existent.
54-5
FACILITATING
MOVEMENT AND
AVAILABILITY
OF
GENETIC RESOURCES
The centers
of
diversity concept
bas
been overplayed in
debates on plant genetic resources. Although these were
valuable for highlighting collecting needs in the past, there is
no longer justification for overemphasizing them. The his-
torical diffusion
of
crops was instrumental in their diversifi-
cation, providing the foundation for crop development. In the
case
of
wheat
(Triticum
aestivum
L.), early cultivars from
Canada were derived from cultivars from Poland, India,
Russia, and England (Knott, 1967) and not directly from
materials in the center
of
origin. Now the genepool
of
several
genera
of
the Triticeae, a tribe
of
the grass family, is
of
value
and species are distributed over vast territories
of
the globe.
Hence, it
is
difficult to understand why the rhetoric devel-
oped for and by developing countries rich in germplasm to
perceive the indigenous plant genetic material as a
national
biological treasure, except where high value industrial crops
had become economically strategic (Chang, 1992). The inter-
dependence
of
global genetic resource conservation centers
and the plant breeding community attest to the fact that area
of
origin has far less consequence than what and how the seed
WILLIAMS"
COHEN
is used, how much is available, its viability, and national
capabilities for storage and use (Cohen & Bertram, 1989).
Modem plant breeding programs are themselves becoming
centers
of
diversity as they continually merge elite lines that
are geographically and genetically diverse (Baezinger &
Peterson, 1992). Rarely is any territory, defined by national
boundaries, self-sufficient in germplasm for continued crop
enhancement.
The key to overcoming the problems
of
an ever-increasing
population, continued problems
of
rural poverty, and the fact
that breeding new cultivars takes considerable time, will be
the ongoing availability
of
genetic resources to sustain crop
enhancement. Debates on sovereignty must not delay such
efforts.
Other factors also are important. They relate to how well
genetic resource collections are managed in terms
of
sample
quality, quantity, security in conservation, uniqueness, in-
ventory status. Limitations in
anyone
of
these areas, espe-
cially in collections involving international custodial respon-
sibilities, will affect the ready availability
of
material for
distribution.
It is not simply a question
of
mobilizing more funding.
There is a major moral responsibility to ensure that the
collections are "in order" and not littered with small samples
in need
of
multiplication, and that they are adequately evalu-
ated and characterized. The constraints are known (Williams,
1989; Goodman, 1990) and there are some hopeful programs
in place to remove restrictions
on
some crop samples. A
program initiated by Agency for International Development
(A.LD.) and implemented by Centro Internacional de
Mejoramiento de Maiz y Trigo (CIMMYT) and
13
national
programs will regenerate essential accessions
of
Latin Ameri-
can and Caribbean maize. Duplicate samples were placed
in
the National Seed Storage Laboratory in Ft. Collins, CO. The
program will regenerate approximately 3,700
of
the most
critical maize accessions (Cohen, 1991).
In many cases, large-scale evaluations are limited by
resources. There is, therefore, clear responsibility to priori-
tize and transfer information among genebanks, and to ad-
dress specific short- and medium-term constraints to produc-
tion. The latter has been stressed by Srivastava and Damania
(1990) in relation to wheat and by Frankel and Brown (1984)
as a matter
of
principle. Unfortunately, however, it has not
been adequately empha'iized in relation to global food needs
of
the next 20 yr when institutional structures and implemen-
tation mechanisms become the main focus
of
discussion
(Keystone, 1991; von Hintum et al., 1991).
Borlaug (1989) summarized the needs for increased pro-
duction, economic policies to encourage adoption
of
new
technologies, and aggressive enthusiastic production cam-
paigns, but warned that the attitude
of
scientists, political
leaders, and the general public will be decisive in determining
whether we reach the food production target that will sustain
our civilization.
Consideration
of
essential food supplies clearly must
be
the over-riding concern
in
setting priorities for further field
collecting
of
germ plasm and evaluation
of
all conserved
materials to promote more rapid use. In part this conflicts
USE
OF
PLANT GENETIC RESOURCES
with
perceived
needs
to
conserve
large
segments
of
useful
diversity
because
of
threats
of
loss.
It
is
impossible
to
con-
serve
everything;
existing collections
are
straining
the
avail-
able
scientific,
managerial,
and
financial
resources.
The
pri-
orities
should
address
the
global
needs
as
well
as
demon-
strated regional
needs
for
a limited
range
of
commodities.
It
is
justifiable
that
more
empbasis
be
placed
on
landraces
of
major
crop
species
than
those
of
the
minor
crops
and
that
collections of
the
former
are
larger.
For
these
minor
crops
and
for
species
of
yet
unknown
potential,
insurance
through
nature
conservation
will
probably
be
adequate
with
specific
segments
of
the
genepools
under
threat
conserved
in
situ
or
ex
sibJ
depending
on
the
degree
to
which
they
are
expected
to
survive
in
for
an
extended
period
without
undue
intervention.
Large
ex
situ
germplasm
collections,
which
are
costly
to
maintain,
are
only
needed
to
ensure
ready
availability
for
use
and
for
preservation of
threatened
species.
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