Transcript Sumber Genetik

 GENETIC RESOURCES:
 Resources that contain all genetic
variability found in a particular plant
species
 This includes its wild relatives; most of
them may have traits useful to breeders.
 GERMPLASM:
 Overall genetic materials possessed by the
plant species
Categories of Genetic Resources
(Hawkes, 1983)
 Crops
i.
ii.
iii.
iv.
Current commercial cultivars.
Old commercial cultivars - no longer planted commercially.
Breeders’ seeds.
Mutants from induced or spontaneous mutations.
 Land Race
Usually from isolated areas or farms. Primitive crops,
usually possessing high variations and grown in
mixtures of genotypes, and sometimes species.
Categories of Genetic Resource
(Cont.)
Weedy Race
 Plants that originated from same progenitor of the
crop species, but possess weedy traits, such as
small stem.
 Capable of invading open fields rapidly, even with
low soil fertility.
Categories of Genetic Resources
(Cont.)
 Wild species
Species from the same genus that could be
crossable to a certain crop species.
CENTRES OF ORIGIN
AND CENTRES OF PLANT DIVERSITY
Vavilov (1887-1941), a Russian botanist
studied diversity and distribution of plants
in the world from 1920’s to 1930’s, and found
that:
 There are higher levels of diversity in
certain parts / regions in the world for
certain kinds of plant.
 Revealed eight centres of origin for main
crops.
1. Chinese Center (China)
 Cereal and legumes: eg: Soybeans (Glycine max)
 Roots, vegetables eg: Radish(Raphanus sativus) chinese cabbage (Brassica
rapa chinensis)
 Fruits and nuts eg: Oranges (Citrus sinensis), litchi (Litchi chinensis)
 Sugar, drug plants eg: Tea (Camellia sinensis), sugar cane (Saccharum sp.)
Distribution and origin of plants
2. Indian Center
 Cereal and legumes eg: Rice (Oryza sativa),
chick pea (Cicer arietinum)
 Vegetables and tubers eg: Egg plant
(Solanum melongena) Cucumber (Cucumis
sativus)
 Sugar, oil, fiber plants eg: sugar cane
(Saccharum spp.), kenaf (Hibiscus
cannabinus)
 Spices eg: Black pepper(Piper nigrum)
Distribution and origin of plants
2a. Indo-Malayan Center
 Fruits eg: Pomelo (Citrus maxima), Banana
(Musa spp.) Coconut (Cocos nucifera),
mangosteen (Garcinia mangostana), Durian
(Durio zibethinus)
 Oil, sugar, spice plants eg: Nutmeg (Myristica
fragrans),Cloves (Syzygium aromaticum)
3. Central Asiatic Center
 Grains and legumes eg: Wheat(Triticum aestivum), Pea
(Pisum sativum)
 Vegetables eg: Carrot (Daucus carota), spinach (Spinacia
oleracea)
 Fruits eg: Apple (Malus pumila), grape (Vitis vinifera)
Distribution and origin of plants
Central Asia
4. Near Eastern Center
 Grain and legumes eg: Wheat (Triticum aestivum), Barley
(Hordeum vulgare)
 Fruits eg: Melon (Cucumis melo), Pomegranate (Punica
granatum)
 Forage plants eg: alfalfa (Medicago sativa)
Distribution and origin of plants
Near East
5. Mediterranean Center
 Cereal and legumes eg: Wheat (Triticum durum), oats
(Avena sativa), Broadbean (Vicia faba)
 Oil and fiber plants eg: Olive (Olea europaea) , black
mustard (Brassica nigra)
 Vegetables eg: Cabbage (Brassica oleracea)
 Ethereal oil and spices eg: peppermint (Mentha spp.),
thyme (Thymus mongolicus)
Distribution and origin of plants
6. Abyssinian/Ethiopian
(African) Center
 Grains and legumes eg: Wheat (Triticum durum), Barley
(Hordeum vulgare)
 Misc: Coffee (Coffea arabica), okra (Abelmochus
esculentus)
 Oil palm (Elaeis guineensis)
Distribution and origin of plants
/Ethiopian
(African)
7. South Mexican and Central
American Center
 Grain and legumes eg: Corn (Zea mays), Common
bean (Phaseolus vulgaris)
 Melon plants eg: Pumpkin (Cucurbita spp.)
 Misc: Chilli (Capsicum annum), cocoa (Theobroma
cacao)
Distribution and origin of plants
South
Mexican
& Central
American
Center
8. South American (PeruvianEcuadorean-Bolivian) Center
 Root tubers eg: Sweet potato (Ipomoea batatas), Potato
(Solanum tuberosum)
 Vegetable crops eg: Tomato (Solanum lycopersicum)
 Fruits and misc eg: Papaya (Carica papaya), Tobacco
(Nicotiana tabacum)
Distribution and origin of plants
8a. Chilean Center
 Potato (Solanum tuberosum)
Distribution and origin of plants
8b. Brazilian-Paraguayan Center
 Cassava (Manihot esculenta)
 Groundnut (Arachis hypogea)
 Cocoa (Theobroma cacao)
 Rubber (Hevea brasiliensis)
 Pineapple (Ananas comosus)
 Passion Fruit (Passiflora edulis)
Distribution and origin of plants
GERMPLASM CONSERVATION
Erosion or loss of genetic resources happened and is
continuously happening at a serious rate due to:
 Deforestation – Lost of wild species and
weedy races.
 Use of modern varieties – Lost of land
races, primitive crops and weedy races.
 Development –Lost of land races,
primitive crops varieties, etc.
Therefore, conservation is needed to conserve crop genes and genotypes,
to prevent genetic vulnerability
STEPS IN
GERMPLASM CONSERVATION
1. Exploration
 Exploration is done to understand the crop
distribution.
 Plant collection is conducted to obtain samples that
consist the maximum genetic diversity.
Where?
Native habitats of selected crop
Farm where crop is planted, including small farm
Market
Other entities/ institutions
STEPS IN GERMPLASM
CONSERVATION (cont.)
2.Collection
 Random sampling
To obtain variation that represents population of the
crop.
 Selected sampling
Done for plants with specific character. The collection
may not represent the actual variation. Therefore,
selected sampling has to be done concurrent with
random sampling.
STEPS IN GERMPLASM
CONSERVATION (Cont.)
3.
a)
Maintenance / Conservation
In situ – grown in natural habitat
Maintain the original forest ecosystem, grassland,
Vavilov’s centre of diversity, forest parks.
3. Maintenance / Conservation (Cont.)
b)Ex-situ
 Collections
Seed bank
Requirement:
Cold room, 10oC
Maize seed bank
Relative Humidity, 2-5%
 Living Plants
Botanical Gardens
Arboretum
Field genebanks
arboretum
3. Storage (Conservation)
b)Ex-situ (Cont.)
 Pollen storage
Requirement: Cold room, 10oc to 20oc
Relative Humidity, 8 -25%
 In-vitro method
- Tissue culture– slow growth
- Cryopreservation- Liquid
nitrogen (-196oc)