Conservation of Genetic resources Flashcards
5 key indicators of CBD
- Trends in abundance and distribution of selected species
- Change in status of threatened and/or protected species
- Trends in the extent of selected ecosystems and habitats
- Trends in genetic diversity of domesticated animals, cultivated plants and fish of socio-economic importance
- Coverage of protected areas
Agricultural biodiversity includes:
Crops Livestock CWR Semi-domesticated relatives of livestock Pollinators Fauna and Flora Soil microorganisms
Issues with crops
30 plants provide 95% of all calories, 12 make up 75% and 4 provide 60%
Food production needs to increase by 70%, CC is reducing this by 2% each decade
Why is crop diversity important?
Ensures stability and reduces risk, ensures food security, and reduces the threat of disease
Threats to agrobiodiversity
Replacement by modern varieties/breeds Agricultural infestation (vulnerable to disease) Changes in land use Increased human population Human poverty Land degradation Social, economic and environmental change Climate change
Ex situ agrobiodiversity strategies
Field gene bank
Cryopreservation
Seed storage
Tissue culture
In situ agrobiodiversity strategies
On-farm
Home gardens
Wild habitats
(unable with recalcitrant)
Define genetic resources
Genetic material of animals and plants which is of value as a resource for the present and future generation of people
Aim of agrobiodiversity
To conserve a broad range of genetic diversity found in target species to maximise chances of conserving potentially adaptive genes
Germplasm accessions
Currently, 7.4 million germplasm accessions have been conserved, 70% of the genetic diversity of 300 plants has been conserved
When does crop domestication occur?
Unconscious selection for seed retention Modifications of glumes Reduced seed coat thickness The greater size of harvested organs Rapid and uniform germination Synchronisation of flowering
Where has crop domestication occurred and whats the impact of this?
Fertile Crescent, near Syria, Turkey etc
Has led to centres of diversity, there are 8 world centres which are the crops centre of origin
Define CWR
A wild plant taxon that has an indirect use derived from its relatively close genetic relationship to a crop. The relationship is determined in terms of the CWR belonging to gene pools 1 or 2 or taxon groups 1 to 4
Gene pools
GP - 1: A cultivated form and the wild form of the crops
GP - 2: Includes the coenospecies (gene transfer possible)
Taxon groups
TG - 1: Same species or same crop
TG - 2: Same series or section
TG - 3: Same subgenus
TG - 4: Same genus
UK CWR conservation efforts
50 designated sites to CWR protection
CWR genetic reserve established in Cornwall
In situ CWR conservation
Genetic reserves
On-farm
Home garden
Ex situ CWR conservation
Seed storage
Field gene banks
Botanic gardens
In vitro CWR conservation
Slow growth
Cryopreservation
DNA
Orthodox seed species include:
Seeds with high viability
Long term conservation
How to store seeds
Either;
1. Reduce moisture content to 5% then store at -20
2. Reduce moisture content to <5% and store at room temp
Recalcitrant seeded crops cant be frozen and so can be kept in a field gene bank
Explain in vitro storage
Used with slow growing plants, germplasm of the mother plant establishes shoot culture (micropropagation) Subculture is then transferred onto growth retarding medium and stored at a reduced temperature, this is repeated every 3 years
Define breeds:
A group of domestic livestock with definable and identifiable external characteristics that distinguish it from others of the same species
Threats
Only found locally, and lack of genetic diversity
