Gene conservation

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Gene conservation

• Dag Lindgren
• 2002

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Would not it be nice to have them living at
present ?
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Genes (or rather species) are exhausted

• Species get extinct 1000 times faster
• Megafauna vanished when human come
• Many species get extinct without ever been known
• It took million of years to recover from the last
  mass extinction (65 million years ago)

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Species sustainability
Sustainable development of a species is greatly
dependent on amount of genetic diversity present
in its populations. With no gene diversity threat
for extinction is much higher Gene conservation
aims to conserve and maintain the adaptive
potential of certain representative populations
within a species to secure maintenance of
sufficient gene diversity.
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Human Impact

• Grazing
• Hunting
• Fire regime (now end of fires)
• Cultivation
• Reservates
• Fragmentation
• Harvesting (earlier creaming)
• One seed one tree (no place for selection)
• Planting
• Silviculture, horticulture and gardening
• Domestication
• Transfers
• Changing pollen cloud
• In particular spruce in south Sweden

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Domestication

• Domestication of plants and animals use only a
  small and decreasing share of the natural gene
  resources
• The green revolution, the commercialisation and
  the globalisation has reduced small scaled
  utilisation

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Motives for gene conservation

• Safeguard continued existence and evolution
• Safeguard threatened races and variants (air
  contamination, elm disease, goats on Guadeloupe)
• Avoidance of contamination from cultivars
• Future utilization of genes (breeding material)
• Backup for mistakes
• Reference for future research
• Museal
• Preserve the character of other components of the
  ecosystem
• Ethic and Moral
• Comply to political decisions and social demands

Distinct tree populations exist in different
parts of the country
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Glaciation
During the last 2 million years repeated
glaciations caused an unbalance. Our species are
hardy, flexible, fast migrating rather than the
result of millions of years of fine-tuning to the
local conditions.
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European and Nordic Forest Gene conservation
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EUFORGEN

• The European Forest Genetic Resources Programme
  (EUFORGEN) is aimed at ensuring the effective
  conservation and sustainable use of forest
  genetic resources in Europe.
• EUFORGEN became operational 1994.  
• EUFORGEN is currently financed by the
  participating countries and is coordinated by the
  International Plant Genetic Resources Institute
  (IPGRI), in collaboration with the Forestry
  Department of the FAO.

• EUFORGEN operates through networks in which
  forest geneticists and other forestry specialists
  meet and work together to discuss the needs,
  exchange experiences and develop conservation
  methods for selected species.
• These networks also contribute to the development
  of conservation strategies for the ecosystems in
  which these species belong.

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Forest resource data for the Nordic countries
From Tree Gene Resource Management in the Nordic
Countries a review of the situation in 2002
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Forest regeneration methods and annual restocking
areas for the Nordic countries
From Tree Gene Resource Management in the Nordic
Countries a review of the situation in 2002
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Protected areas in NW Europe
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Main woody species and gene resource management
activities in the Nordic countries
Origin Gene Reserves
ex situ . In situ clones Planned
) indigeneous introduced

 
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Coordination breeding-conservation

• Genetic diversity is the raw material for
  breeders and breeders want to conserve diversity
  in breeding populations
• Controlled crosses reduces effect of uncontrolled
  gene migration
• Swedish breeders work with thousands of parents,
  enough to keep rare alleles (1) in population
• Swedish breeders work with many reproductively
  isolated subpopulations, which is useful for
  conservation
• Coordination offers advantages
• Breeders materials are well defined and
  documented

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Multiple population breeding system (MPBS)

• Splitting the gene resource population into
  subpopulations helps conservation (as well as
  breeding). The selection pressure will act
  somewhat differently in different subpopulations.
  This can be further strengthened by planting
  populations on the species fringe, and diversify
  management and selection among subpopulations.

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Dynamic or static?
Static Freezing the existing
Dynamic Promoting adaptation
Ex situ storage of parents (e.g. clone
archives) Conserve seed samples for
long Satisfactory large sample and effective
population size
Benefit from natural selection for
adaptation Satisfactory large effective
population size Protect somewhat (mainly from
human caused pressure)
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Genetic reserves (example)
A sound stand selected as representative sample
of stands in local selective environment
(breeding zone), more conservative stands may
also be reserves
Better young to middle aged (distinctive traits
expressed)
No poor stands of the same species in vicinity (
may be used as a seed source)
Trees representative to local selective
environment
Natural regeration (if possible)
     
Area gt 3 ha
lt than 10 of other species
Optimum site type
Regenerated only from seed of the orginal stand
trees
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Gene conservation methods
Static- freezing of representative genotype
samples in clonal archives or gene (seed) banks
Dynamic- exposing representative sample of
genotypes to evolutionary development to increase
their adaptedness
Gene banks, clonal archives, seed orchards
Ex situ breeding populations
In situ gene reserves
In gene reserve the new regenerating progeny are
subjected to the action of evolutionary forces so
that their adaptive potential is maintained .
- freezing means that the genetic structure
of the stored genes is constant, while
environment may change and these genes may not be
fit (so that it is used as a back-up no need for
costly banks)
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Gene reserve management
Objective to maintain sustainability via a
multi-aged structure and continuous regeneration
Other species tolerated if they do not disturb
the target species
Good health condition
Regular thinning to improve light regime and
promote regeneration
Irregular removal of shrub-layer to promote
regeneration
Protection of new regeneration (maybe fencing)
Soil scarification better regeneration
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Clonal archive
Clonal archive is an ex situ (moved from the
place of natural occurance) gene conservation
unit. Archive is made of a collection of grafted
scions from the conserved trees (earlier used to
be plus trees) and may be used as a seed orchard
at the same time.
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Other types of gene conservation

• Reserves for mixed purposes often also
  contributes to gene conservation
• Experiments
• Botanic gardens
• Arboreta
• Varied uses (gardens leehedges)
• Impediments

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Swedish land area
Forest
22 740 000 ha
Peatland
4 544 000 ha
Mountain
4 527 000 ha
Agriculture and grazing
3 510 000 ha
Other ground
5 774 000 ha
There are trees on land which is not exposed to
forestry. Even on the forest land all forests
are not managed.
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Not critical?
Motives why it may not be that important with
gene conservation (of Norway spruce and Scots
pine in Sweden)

• Large areas
• Many trees (billion of parents)
• Limited current local human influence
• Large impact of human over long time (actually
  our ecosystems have never been wild).
• Similar populations have similar genes
• Almost all important alleles exists in any small
  group of trees
• Population differences probably caused by
  frequency of common genes
• We share species with our neighboors, thus
  redundancy, diversity in actions and reduced need
  for action
• We have few species, thus lower total needs for
  action
• The normal condition for Sweden is glaciation.
  The Swedish biodiversity exists only in the short
  time window between glaciations
• Species adapted for fast adaptation (after
  glaciation)
• Boreal species have wide adaptation
• Large Swedish areas have never been subject to
  culture, a large part of the current forest is
  not affacted by breeding
• The bred forest is similar to the non bred
• Genes are effectively moved around, mainly by
  pollen flow

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The Swedish Forest is not that changed by forest
improvement!

• Some areas are never cut
• "Natural" regeneration at perhaps 35 of the
  harvested area
• Only half of the planted plants (2000) originate
  from seed orchards
• Before 1950 plantation was rare (but seeding more
  common) and bred plants hardly existed before
  1970
• On average 25 of the trees that form the stand
  in a young plantation are not planted
  ("volonteers")
• Half of the pollen in a seed orchard does not
  come from the seed orchard trees
• Only one quarter of the genes in the forest
  created today originate from seed orchards
• The bred trees are genetically similar to the
  non-bred and there is a considerable over-lap
• The improvement degree in the current forest may
  just compensate for previous centuries of
  negative selection

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Swedish gene resource conservation

• Gene Bank managed at the National Board of
  Forestry
• Started 1980
• Conservation of local populations in stands
• Contracts
• Normal management
• Tricky regeneration, but seldom as rotation is a
  century
• Norway spruce there are 67 plantations in north
• 6 clone archives in south
• Scots pine 171 documented naturally regenerated
  stands spread over the country.
• In southern Sweden also a graft archive
  representing three native populations.
• For oak there are 6 plantations with wind
  pollinated progeny from 513 families.
• Part of the preservation takes place in the 1000s
  of parents in forest tree breeding.
• For other forest tree species there are no
  significant activities.
• Parts of Sweden are different types of reserves
  and there exist arboreta and botanical gardens.
  These actions can be of importance especially for
  all other species, which are not actively taken
  care of by the Forest Gene Bank.

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Geographic distribution of spruce gene
conservation objects
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Object for gene conservation of pine
The regeneration is more important than the old
trees!
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Genbank stand
Documentation Contract
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Belarus and Baltic Norway spruce

• Share in plantings 1995 south Sweden gt65
• Götaland is strongly influenced by planting
  foreign spruces since 200 years
• Spruce reached Götaland a millenium ago and is
  closely related to that on east side of the
  Baltic, and pollen migrates naturally so
  probably limited problem

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