Genetic resources of potato

Ningappa kirasur2014-12-129Dept. of OlericultureCOH, Vellanikkara

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Potatoo Solanum tuberosum

o Solanaceae

o 2n=48

o South America

o Fourth important food crop after rice, wheat and

maize

o Introduced to India in 17th century by Portuguese

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Biosystematics

o Genus Solanum - consists of >2000 species

o More than 200 species were tuber bearing species including

20 cultivated species

o The tuber bearing species are grouped under the section -

petota, sub section potatoe with 19 series.

o Among cultivated species , two important auto tetraploids

o S. tuberosum ssp tuberosum and S. tuberosum ssp andigena

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Contd…

o Two diploid species are S. phureja and S. stenotomum

o Other wild species of the series tuberosa are,

o S. sparsipilum, S. leptophys, S. berthaultii, and S.

spegazzinii, S. vernei

o Cultivated potato is crossable with other cultivated species

and wild diploid species

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Contd…

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Contd…

o Wild species have been found useful for transgression of

genes for resistance to diseases and insect pests

o The cultivated species S. tuberosum ssp tuberosum -

widely spread in Europe, USA, Canada and Asia

o While S. tuberosum ssp andigena - is grown only in the

andeas of South America

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Origin and domestication

o Potato is originated in the Andean region of Peru and

Bolivia in south America

o It was domesticated in 10,000 – 7000 years ago

o First domesticated species was Solanum stenotomum,

which originated from the wild species S. leptophyes

o The other progenitors of present day cultivated potato,

with three wild species S. sparsipilum, S. acaule and S.

megistacrolobum

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Contd…

8 Origin and domestication

Cytology

o Basic chromosome no. x=12

o Diploid 2n=2x=24

o Triploid 2n=3x=36

o Tetraploid 2n=4x=48

o Pentaploid 2n=5x=60

o Hexaploid 2n=6x=72

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1. Solanum stenotomum

2. Solanum phureja

3. Solanum goniocalyx

4. Solanum ajanhuiri

Diploid species (2n=2x=24)

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Triploid species (2n=3x=36)

1. Solanum chauch

2. Solanum juzepczukii

Pentaploid species (2n=5x=60)

3. Solanum curtilobum

Contd…

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Ploidy levels in potato

Ploidy level Numbers Percentage

2x 129 73

3x 7 4

4x 27 15

5x 3 2

6x 10 6

Total 176 100

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Variability of tuber size in potato

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Wild species

1. Solanum leptophyes

2. Solanum sparsipilum

3. Solanum acaule

4. Solanum megistacrolobum

5. Solanum bolivense

6. Solanum demissum

7. Solanum microdontum

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Solanum tuberosum var. tuberosum

Solanum vernei var. vernei16

Solanum laxum

Solanum hjertingii 17

Solanum microdontum

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Solanum demissum

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Solanum tuberosum var andigena

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Solanum dulcamara

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Solanum acaule

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Solanum donianum

Solanum ensifolium

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Solanum species Traits of interest

S. andigena Late blight, immune to virus x and y

S. bulbocastanum Late blight resistance

S. jamessi Fusarium wilt resistance

S. pinnatisectum Late blight resistance

S. stenotomum Frost resistance

S. stoloniferum Immune to PVA and PVY , resistance to late blight

S. multidissectum Nematodes resistance

Species used for introgression of genes in to potato

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Source of resistance in wild species

o Solanum demissum - late blight, leaf roll virus

o Solanum acaule - PVX, PLRV, spindle tuber viroid

o Solanum chacoensis - PVA, PVY, late blight, tuber moth

o Solanum spegazzinii - Fusarium, wart, cyst nematode

o Solanum stoloniferum - PVA, PVY

o Solanum vernei - Cyst nematode

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Potato germplasm conservation institutes

o CIP- International potato center - Peru

o CPRI- Central potato research institute- Shimla

o Gene bank holds 80% of the worlds native potato and sweet

potato germplasm

o Also maintains more than 1,500 accessions of native

Andean root and tuber crops (ARTCs )26

Contd....

o In vitro germplasm is available for distribution

o Used in breeding programs over 100 countries

o CIP’s in vitro gene bank is the first to obtain International

Standards Organization (ISO) 17025 accreditation for safe

and secure germplasm movement

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Contd…

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THANK YOU

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