SUMMARY
STUDY OF THE SPECIES BELONGED TO ASTRAGALUS L. GENUS IN
NAKHCHIVAN AUTONOMOUS REPUBLIC
Ganbarov D.
Works of researchers who have a contribution in study of the species to date belonging to the
Astragalus L. Genus have been studied. That will give them a possibility of a right determination
of our further researches’ direction by referring to them. According to the literature references
Astragalus L. Genus includes into multyspecies row.
According to references of published information there are 85 species that belong to the
Astragalus L., Astracantha Podlech Genera in the region.
РЕЗЮМЕ
ИСТОРИЯ ИЗУЧЕНИЯ ВИДОВ
ОТНОСЯЩИЕСЯ К РОДУ ASTRAGALUS L. В НАХЧЫВАНСКОЙ
АВТОНОМНОЙ РЕСПУБЛИКИ
Ганбаров Д.
Наша цель в представляемой статье выяснить работы исследователей, которые
более или менее затруднились в изучении видов относящиеся к роду Astragalus L. до
сегодняшнего дня, опираться на них, правильно определять направление последующих
исследовании.
По литературным сведениям в территории региона имеются 85 видов, которые
относятся к роду Astragalus L., Astracantha Podlech.
Ключевые слова: Растительность, флора, род, вид, астрагал, классификация,
экосистем, фитоценоз
Key words: vegetation, flora, genus, species, Astragalus, classification, ecosystem, phytocenosis
AMEA Botanika İnstitutunun elmi əsərləri, 2012- ci il, XXXII cild
PLANNING OF EX SITU CONSERVATION METHODS FOR SOME ENDEMIC PLANT
SPECIES OF AZERBAIJAN
Salimov R.A.
Post-doc. researcher of Botany Institute of the ANAS
Central Botanical Garden of the ANAS
Different methods of plant genetic diversity conservation in general and new methods that are
intended for ex situ conservation of some endemic plant species in Azerbaijan have been
presented in the article.
Key words: ex situ, endemic species, seed bank.
Introduction
One of the critical challenges facing the world today is the conservation of the biological
diversity and use of its components for the benefit of humanity. The breadth of plant diversity
plays a pivotal role in the functioning of all natural ecosystems, as well as providing direct
benefits in terms of food and medicine for humans and foodstuffs for wild and domesticated
animals. And human life depends on plants. These constitute the basis for food, supply most of
our needs (including clothes and shelter) and are used in industry for manufacturing fuels,
medicines, fibres, rubber and other products. However, the number of plants that humans use for
food is minimal, compared with the number of species existing in nature. Conserving genetic
diversity is an essential component of sustainable plant management. Genetic diversity is also
critical for artificial selection and breeding for forest products and other environmental services.
Plants hold the genetic keys to enhanced quality of life today and will help us determine whether
life will be worth living tomorrow. So, we have an ethical obligation to protect genetic diversity
for future generations, partly because we cannot predict which traits will be important in the
future.
Azerbaijan has a rich, diverse flora of more than 4500 species. Some of these species are at risk
of extinction in the wild by human and other influences (e.g. clearing, disease, weed invasion,
habitat loss and deforestation from urbanization, conversion to agriculture, overgrazing,
overharvesting without regeneration, and replacement of native forests with non-native
plantations) with over 250 species considered to be rare, threatened or poorly known and
approximately 200 species are endemic plants. These threats to plant genetic diversity include
threats to species, populations, and genetic variation within populations.
In this paper, the different methods of the conservation of plant genetic diversity in general and
present some data on the state of endemic plant species in Azerbaijan were summarized. Finally,
how conservation of these endemic plant species could be planned and improved in the future
were discussed.
Materials
The present work will be based on ex situ conservation of some endemic plant species of
Azerbaijan. The selected plant species will be collected and identified with the help of national
floras and books (3).
AMEA Botanika İnstitutunun elmi əsərləri, 2012- ci il, XXXII cild
Prioritization of species for ex situ conservation is based primarily on the level of threat and
economic usage. Where species are known from many populations, ex situ conservation methods
can effectively sample flora populations over the full range of their distribution. Numerous small
populations may be challenging to preserve on site, whereas the sampling and storage of
propagules over many populations of a species are reasonably easily undertaken.
Material would be available for biochemical, physiological, and molecular research, and material
could be provided for ex situ propagation as needed for recovery programs and educational
purposes.
Methods
As a general guideline, plant genetic diversity conservation should focus on species with current
or potential economic importance and/or under immediate threat of extinction. Plants are
conserved according to their current or future usefulness to humans. A wide range of methods,
from protected nature reserves to intensive management of breeding populations for production
systems, can be applied to conserve plant genetic resources. The choice of methods depends on
the objectives of conservation, available genetic material and selected time scale. The choice of
methods and subsequent implementation of the conservation strategy also depends on the
availability of human and financial resources.
The intimate link between plant genetic diversity, conservation and utilization is shown below in
Figure 1, which illustrates a detailed model for plant genetic conservation proposed by Maxted et
al. (8). Within this model it can be seen that there are two basic conservation strategies, each
composed of various techniques. Plant genetic resources can be conserved in their natural
habitats (i.e. in situ), in conditions different from those of their natural habitats (i.e. ex situ) or in
a combination of in situ and ex situ methods, that is, in complementarity. The selection of one or
more methods depends on needs, possibilities and targeted species.
There is an obvious fundamental difference between these 2 strategies: ex situ conservation
involves the sampling, transfer and storage of the species (or components of biological diversity)
away from the original location, where they are found, whereas in situ conservation involves the
designation, management and monitoring of species growing in their place of origin or at the
location, where they are currently found. In other words, in situ conservation means the
conservation of ecosystems and natural habitats and the maintenance and recovery of viable
populations of species in their natural surroundings and, in case of domesticates or cultivated
species, in the surroundings where they have developed their distinctive properties. And one goal
of in situ conservation is to allow normal evolutionary processes to occur (4, 6, 9). In situ
conserved material may require a time-consuming and costly expedition to obtain samples of
material before the can take place and in situ conservation in a genetic reserve or on farm alone
cannot guarantee long-term security for a particular crop or wild species. On the other hand, one
significant advantages of ex situ conservation is that the genetic material is always available to
the plant breeder or for evaluation, such as resistance to a particular pest or disease.
Ex situ conservation strategies have also several specific techniques or tools as indicated in
Figure 2. Ex situ tools are numerous and vary widely in their costs and benefits (both financial
and biological), and in their spheres of application (7).
Seed banking: The collection of seed samples at one location and their transfer to a gene bank for
storage. The samples are usually dried to a suitable low moisture content and then stored in
conditions of low moisture and temperature. Routinely used for orthodox seeds of crops and wild
species.
AMEA Botanika İnstitutunun elmi əsərləri, 2012- ci il, XXXII cild
Tissue culture ( in vitro) storage: The collection and maintenance of explants (tissue sapmles) in a
sterile, pathogen-free environment. Somatic tissue stored in vitro under temperature and light
conditions controlled for slow growth.
Field gene bank: The collecting of seed or living material from one location and its transfer and
planting at a second site. Open-air, extensive planting to maintain genetic diversity within a
species, often used for woody commercial species. Large numbers of accessions of a few species
are usually conserved.
Botanic garden or arboretum: The collecting of seed or living material from one location and its
transfer and maintenance at a second location as living plant collectios of species in a garden or
for free tree species an arboretum. Small numbers of accessions of a large number of species are
usually conserved.
Cryopreservation: Seeds, pollen, or tissue frozen in liquid nitrogen. Used for the long-term
storage of agricultural and horticultural taxa; increasingly used for wild species.
Figure 1. A model for plant genetic conservation (Maxted et al., 1997)
AMEA Botanika İnstitutunun elmi əsərləri, 2012- ci il, XXXII cild
Figure 2. A model for plant genetic conservation (Maxted et al., 1997)
Ex situ conservation maintains specific genetic combinations, generally requires less space and is
relatively easy to control (less dependent). In the same time ex situ conservation often require
special facilities and trained personnel and often involve risk of disease transmission; does not
allow continuous adaptation to changes in the environment and conserve associated species in the
ecosystem. The relative advantages and disadvantages of each of the ex situ conservation
techniques outlined are summarised in the following table. It is clear that each technique exhibits
advantages and disadvanteges, but which is used for which species is governed by the nature of
the species themselves and the kind of exploitation, if any, that is to follow conservation.
Relative advantages and disadvantages of the
various ex situ conservation techniques (Maxted et al., 1997)
Methods
Advantages
Disadvantages
Seed
banks
Efficient and reproducible;
Feasible for medium and long-term secure
storage;
Wide diversity of each target taxon
conserved;
Easy access for characterisation and
evaluation;
Easy access for utilization;
Propagules ready for use;
Relatively inexpensive;
Little space required (small seeds);
Not applicable to species with
recalcitrant seeds not to vegetatively
propogated species;
Freezes evolutionary devolopment,
especially that which is related to pest
and disease resistance;
Space required (large seeds);
Genetic divesrity may be lost with
each regeneration cycle (but
individual cycles can be extended to
periods of 20-50 years or more)
Tissue
Minimum space required;
Sampling problems (representative
Botanic Gardens
Seed banks
In vitro tissue culture
DNA banks
Field genebanks
DNA banks
Cryopreservation
Pollen banks
AMEA Botanika İnstitutunun elmi əsərləri, 2012- ci il, XXXII cild
culture
(in vitro)
storage
Genetic erosion reduced if methods such
as cryopreservation are used;
Applicable to species with orthodox and
recalcitrant seeds, and to vegetatively
propogated material;
Intra- and inter-population variation can
be conserved provided species range
adequately sampled;
Aseptic conservation (minimises disease
risk);
Time required to produce propagules for
use is short;
Easy access for utilization
individuals and within individual);
Need to develop individual maintaince
protocols for most species;
Problems of somaclonal variation and
early maturation;
Relatively high-level technology and
facilitity costs
Resources prone to loss by accident,
pests,
diseases;
Relatively expensive (generally not a
preferred alternative for genotypes
without
actual socio-economic value)
DNA
storage
Relatively easy, low-cost conservation
Regeneration of entire plants from
DNA cannot be envisaged at present;
Problems with subsequent gene
isolation, clonning and transfer
Pollen
storage
Relatively easy, low-cost conservation
Need to develop individual
regeneration protocols to prduce
haploid plants; further research
needed to produce diploid plants;
Only paternal material conserved but
mixtures from many individuals could
be envisaged
Field
gene
bank
Suitable for storing material of
“recalcitrant” species;
Easy access for characterisation and
evaluation;
Material can be evaluated while being
conserved;
Easy access for utilization;
Material is susceptible to pests,
diseases and vandalism;
Involves large areas of land, but even
then genetic diversity is likely to be
restricted
High maintaince cost once material is
conserved
Botanical
garden
and
arboreta
Applicable to species with orthodox and
recalcitrant seeds, and to vegetatively
propogated material;
Freedom to focus on wild or non-
economic plants;
Useful method for unique
phenotypes/genotypes (eg mutants,
variants, sterile types);
Easy public access for conservation
education
Space or glass houses required, so
genetic diversity is likely to be
restricted;
Resources prone to loss by accident,
pests,
diseases;
High maintenance cost in glasshouse
once conserved
At the planning and collecting stage, I will pay attention to a series of guidelines and protocols
for collection, storage, monitoring, and documentation of germplasm that have been developed in
Millennium Seed Bank (Kew, Royal Botanic Garden, UK) to ensure that the highest-quality
AMEA Botanika İnstitutunun elmi əsərləri, 2012- ci il, XXXII cild
genetic material is acquired and maintained. These guidelines are derived from published
international standards (1, 2, 5, 10, 11, 12). Guidelines for quality assessment, quantification, and
germination testing have been developed on a species-by-species basis following Hanson (5) and
Touchell et al. (1997). There is no definitive method for sampling and handling of all species; for
instance, defining an adequate sample will vary between populations and species and will depend
on the extent and distribution of genetic variation within a species as well as the biology,
ecology, and longevity of the species.
Result and Discussion
As in any strategic process, the conservation of plant genetic resources implies planning and
decision-making. The first steps of the model are the planning stages, for example, how to go
about selecting which species to conserve and where to find information on the selected group,
etc. So, for conservation, priorities need to be established with regard to (a) the type of material
to be conserved (‘at-risk’ species or those of interest to food and agriculture), (b) the activities
that are to be conducted afterwards, and (c) the resources available for carrying out these
activities. Priorities may vary but those of conservation and germplasm use are the most
important objectives. A strategy should be developed for taking samples, for their handling in the
field so that they survive the journey to the place of conservation and for their documentation as
they are collected. Likewise, permits must be requested from appropriate authorities and the
regulations observed of the respective countries where collecting will be done. Once the permits
are obtained, the logistics of the trip are prepared.
In particular, it is expected to create a working group or a team, which will complete the
information on a various endemic plants and distribution of some species from existing sources,
to supplement the results of their field trips, which focus on the important areas where data are
insufficient to create a database. Working groups will be coordinated by the staff of the Royal
Botanical Gardens, Kew, who have a wide experience of management of such international
projects and owning the modern approaches to solution of the problems of conservation. The
database will be used for GIS analysis and determination of priority sites and critical areas of
conservation. It will allow establishing the species richness and concentration of rare and
endemic species for special conservation. This work will promote expansion of the efforts
focused in the Caucasus and is important for cross-border cooperation to improve the process of
saving the flora of the Caucasus.
To implement the above objectives to conserve some endemic plant species Azerbaijan in ex situ
conditions the following necessary steps are to be taken:
1.
To prepare collecting target list of the Azerbaijan’s priority endemic species (economic,
endangered, threatened and etc.)
2.
Collect at least 15 target species each year
3.
Clean and assess the quality and quantity of all collections
4.
Duplication of seed collections, herbarium specimens and field data to Botany Institute.
5.
Designed data base and data management
Specific action(s) I will take to improve the quality of my institute’s collections:
1.
Especially at the planning and collecting stage, pay attention to protocols and guidelines of
MSB to make quality collections.
AMEA Botanika İnstitutunun elmi əsərləri, 2012- ci il, XXXII cild
2.
To achieve success of seed collections of target species, during production of a target species
list, include locations, phenology and expected seeding times.
3.
To make long-term conservation collections, available for research and use in the future (re-
introduction and etc.), I aim to make large collections as much possible as in each collection
(simple random and even or systematic seed sampling from each of 10-50 individuals (it depends
on available populations))
4.
Maximize the diversity within the sample by collecting as much possible seeds from different
populations.
The ex situ conservation program provides a means for investigating the reproductive biology of
some threatened and/or endemic plant species of Azerbaijan. Research into reproductive biology
provides a vital understanding of the nature of growth and recruitment in populations, helping to
ensure a successful recovery. Long-term research into the physiological changes in seed viability
during storage and germination and monitoring of that seed over time is a prerequisite for the ex
situ program. And for some threatened and/or endemic plants, an ex situ program is the key to
survival.
This information will hopefully provide the main basis for establishing ex situ conservation
strategies for biological conservation.
Dostları ilə paylaş: |