Assignment Mechanism of gene bank ,its maintenance, evolution and conservation

2. Faculty of Crop Production
Department of Plant Breeding and Genetics
Registration No.: 2K17-PD -94
Batch: 2K17
semester 8st Semester
Course Code: PBG-606
Course Title : biodiversity and plant genetic resource
Assignment Mechanism of gene bank ,its maintenance, evolution and
conservation
Study Program: B.Sc.(AGRI.)Hons
Submitted By: Hameer Ali
Submitted To: Dr Piar Ali Shar

3. Topic
Mechanism of gene bank ,its maintenance, evolution and
conservation

4. Gene banks
Gene banks are a type of biorepository that preserves genetic material. For plants, this is
done by in vitro storage, freezing cuttings from the plant, or stocking the seeds (e.g. in a
seed bank). For animals, this is done by the freezing of sperm and eggs in zoological
freezers until further need.

5. Mechanism of gene bank
Collecting plant genetic diversity: Technical guidelines
This resource guides new and experienced collectors on how to sample, collect and preserve
a wealth of genetic resources – not only crop plants and trees but also wild species,
symbiotic bacteria
fungi, pollen
Even DNA

6. What is registration
Registration is the first step after acquisition of a sample in any genebank.
Collections in genebanks are the genetic base for current and future breeding programmes
and a source of safety material for distribution to researchers and other users.
Registration is carried out in order to allow genebanks to keep accurate records of samples and
to produce inventory lists for conservation, distribution, and other aspects of germplasm
management.

7. What is sample processing
What is sample processing
The processing of seeds or plant material is the preparation of the samples to be stored. This
is directly linked to the method of conservation, i.e. seed cleaning and drying is related to
seed conservation while extraction and disinfection of plant material is related to tissue
culture or cryopreservation.
Seed cleaning
Seed drying
Seed moisture content determination
Seed packing
To improve the purity of the samples (removing damaged seeds/planting
material).
To optimize storage space and reduce genebank costs.

8. What is germplasm testing
The quality testing of seeds or plant material assures that the material to be conserved is in
good condition, i.e. it can be grown again (viable) and is free of external contaminants (pests
and diseases) and external genes (artificially produced genes
Germplasm is usually tested for
Viability.
Health.
Transgenes.
What is viability testing
Seed or plant viability is the measure of how many seeds or how much plant
material in a lot are alive and could develop into plants that will reproduce
under appropriate field conditions.

9. Health diagnosis
The importance of plant health
Seed or plant health refers to the disease status of a seed or plant sample and the presence
or absence of disease-causing organisms and pests.
Common seed-borne or systemic pests and pathogens
There are four main types of common organisms that are carried in seeds or plant material and
affect a wide range of crops:
Fungi.
Bacteria.
Viruses.
Insects.

10. Transgene detection
What are transgenes
Transgenes are genes that are introduced into another organism or species through
recombinant DNA techniques. Transgenic plants carry transgenes in their genomes and transmit
them to their progeny through normal reproduction.

11. What is germplasm monitoring
Germplasm monitoring is the regular checking of the quality (the viability) and the quantity
(the existing stocks in number or weight) of seeds or plant materials of germplasm accessions
stored in a genebank.

12. Evolution gene bank
Rapidly increasing on-farm biodiversity is a matter of urgency in an era of climate change.
Farmers often have limited access to genetic resources
Sowing the seeds of success
In 2008, with support from Dr Salvatore Ceccarelli, CENESTA started with EPB by providing five
farmers in Kermanshah and Semnan provinces with mixtures of 1,600 different types of barley
supplied by the International Center for Agricultural Research in the Dry Areas (ICARDA). This
mixture included a wide range of germplasm: the wild progenitor, Hordeum spontaneum,
landraces from several countries and modern breeding material. Within such an “evolutionary”
mixture different plants cross naturally to produce new types. Each year, the types produce more
seed and gradually the population becomes better adapted to the specific and changing
circumstances of farmers.

13. Living gene banks
Gene banks perform an important role in the conservation of species, but they freeze not only
seeds but also their evolution at the time of collection. Local varieties and wild relatives must
also be conserved in situ. By combining participation and evolution in breeding programmes,
farmers can guide the evolution of their crop mixtures in the most desirable way for them.
The evolutionary populations can be considered as a living gene bank. Farmers (by themselves
or with scientists) select the most desirable plants and use them in participatory breeding
programmes. For farmers who prefer to sow mixtures rather than single varieties, the
evolutionary populations serve as a source of genetic resources for creating new mixtures. The
importance of having secure access to such a collection of seeds became apparent in Jordan, for
instance, where farmers and scientists turned to evolutionary populations once the civil war in
Syria disrupted their regular source of breeding materials

14. Conservation and maintenance gene Bank
Conservation of plant germplasm can be done on site (in situ) and off site (ex situ).
Conservation a careful preservation and protection of something especially : planned
management of a natural resource to prevent exploitation, destruction, or neglect water
conservation wildlife conservation
In situ conservation
This type of conservation refers to the conservation of germplasm in ecosystems and natural
habitats and the maintenance and recovery of viable populations of species in their natural
surroundings

15. Ex situ conservation
Ex situ conservation
This type of conservation is the storage of seeds or plant material under artificial conditions
(other than their natural environment), to efficiently and effectively guarantee its longevity
viability and availability.

16. ex situ conserveration two types of storage are recognized: storage
of samples for long- term security
Base collections
A base collection is a set of accessions in which each is distinct and as close as possible to the
original sample in terms of genetic integrity. Normally, material is not distributed from base
collections directly to users. Base collections are only used to regenerate active collections (FAO,
2013). In seed banks, samples in base collections are stored for long periods at below 0°C –
usually at -18° to -20°C – to maintain seed viability and, in cryobanks, specially prepared in
vitro culture samples are stored for long periods at -196°C, usually in liquid nitrogen.
Active collections
Active collections consist of accessions that are immediately available for distribution. These
accessions are accessed frequently and storage of active collections can be in seed banks,
vegetative banks, field banks and in vitro banks. Seeds are maintained in conditions that ensure
at least 65% viability for 10-20 years (FAO, 2013) and in vitro cultures are maintained in slow
growth conditions. Samples in vegetative banks are only stored for a few months but perennial
living plants in field banks can be maintained for 20 years or more.

17. Characterization
What is characterization
Characterization is the description of plant germplasm. It determines the expression of highly
heritable characters ranging from morphological or agronomical features to seed proteins or
molecular markers.
It also facilitates a check on the trueness-to-type of homogeneous samples, allowing detection
of misidentifications or duplicates and indicating possible errors made during other genebank
operations.

18. Regeneration
What is regeneration
Regeneration is the renewal of germplasm accessions by sowing seeds or planting
vegetative materials and harvesting the seeds or plant materials which will posses the same
characteristics as the original population.
Seeds or plant materials may also be of poor quality due to low viability or infection. All these
materials require regeneration

19. What is germplasm dissemination
What is germplasm dissemination
Germplasm distribution is the supply of representative samples of seeds or plant material
accessions from a genebank in response to requests from germplasm users. In general, seeds
or plant material is only distributed from active collections.
Genebanks can be more proactive in establishing links with germplasm users, breeders,
researchers, farmers and other groups to enhance the use of the germplasm.

20. Safety duplication
What is safety duplication?
Safety duplication is done for all original seeds collected by the genebank or only held by the
genebank. Seeds which are duplicates from other collections can usually be retrieved from
those collections and do not require safety duplication unless there is doubt about their security
in the other collection.
Maintain at least one duplicate of each accession as a safety back-up.
select a location with a suitable environment, good security and low risk for the duplicate
samples.
Consider costs and practical arrangements.
Seed genebanks
Field genebanks
In vitro genebanks
Cryo genebanks
Packing and shipping
https://cropgenebank.sgrp.cgiar.org/inde
x.php/procedures-mainmenu-243/safety-
duplication-mainmenu-207