Guhitamo icyiza

no

Gukuramwo kibi(Positive and Negative Selections )

By Jean Claude Nshimiyimana, Seed System Officer,

International Potato Center (CIP), Rwanda

Kadahenda, 29/04/2016

Guhitamo icyiza

(Positive Selection - PS)

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Guhitamo icyiza bisobanuye iki?

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Guhitamo icyiza (Meaning of PS)4

� Niyihe mpamvu ituma bahitamo icyiza?

1. Kurwanya indwara no gusaza ku imbuto

2. Guhenda kw’imbuto

3. Kwisigariza imbuto (ntoya)

4. Kongera umusaruro >>30%

Gusaza ku imbuto (seed degeneration)

Primary InfectionSecondary Infection

Gusaza ku

imbuto

Gusaza ku imbuto kuratandukanye no Gusaza ko ubwoko

bw’ibirayi (Seed degeneration is different from variety

degeneration)

Kubera iki? Icyiza

�Abahinzi bafite imirima mito,

�Badafite ubushobozi bwo kugura

�Mu turere imbuto nziza zitaboneka

� Imbuto ihenze cyane

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Impungenge mu guhitamo icyiza8

Ingingo zingenzi iyo uhitamo icyiza(Steps of Positive selection)

� Ni ryari bikorwa?

� Umenya ute ibirayibirwaye?

� Umenya ute ibirayi bizima?

� Wamenya ute ubuzimabw’ikirayi urebeye inyuma(tubercule)?

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Uko bikorwa (Steps):

1. Ikimenyetso ku kirayi kizima,

2. Ibirayi binanutse cg bifite inengeiyariyo yose, ntibirobanurwa

3. Ikirayi cyose kirwaye, kirirengagizwa

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SS

SS S

S

M MM

M

M MM

MM

MSS

SS

S

Ibiranga ikirayi kizima

1. Ikirayi gishishe cg kibyibushye,

2. Umubare w’ibiti bigize igitina cy’ikirayi,

3. Ubushishe bw’igiti cy’ikirayi,

4. Amababi afite ibara ry’icyatsi kibisi cyijimye,

5. Amababi adafite inenge iyariyo yose,

6. Iyo usaruye ureba umubare, ubunini, ndetse n’imiterere y’ ibirayi byeze ku giti cy’ikirayi kimwe.

7. Kuba nta bimenyetso na kimwe cy’indwara zigaragara.

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Indwara n’ibyonnyi

1. Kirabiranya (Bacteriall wilt)

2. Miridiyu (Mildiou)

3. Imfunyarazi (Viruses)

1. Urunyo (leaf miner)

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Uburyo basarura ibirayi

byashizweho ikimenyetso(Harvesting)

1. Mugihe cy’isarura, ubanza gusarura ibirayi birihoikimenyetso, kandi ugasarura kimwe kimwe.

2. Ureba niba ibijumba byicyo kirayi bifiteubuziranenge ugendeye kubunini, umubarendetse n’imiterere.

3. Ibirayi byasaruwe byariho ikimenyetso bihunikwaukwabyo, ndetse bigahunikwa ahantuhabigenewe.

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Gusarura ibyatoranijwe, Gute?14

Gukura imbuto

mbi mu nziza(Negative Selection - NS)

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Gukura imbuto mbi mu nziza

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�Bivuga iki?

Kuvana ikibi mu bizima

� Akamaro:

Ubuziranenge bw’imbuto

Uko bakora icyo gikorwa

1. Ukuramo ibirayi byose birwaye.

2. Ushyira ikimenyetso ahari

ikirwaye.

3. Ibirayi byegereye aho

waranduye ibirwaye,

ntibyemewe

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Kurandura ibirayi birwaye Kirabiranya18

Acknowledgements

We would like to acknowledge Humidtropics and the CGIAR Fund Donors

for their provision of core and project-specific funding without which this

research could not deliver results that eventually positively impact the lives

of millions of smallholder farmers in tropical Americas, Asia and Africa.

This presentation was made at a training workshop on Integrated Potato Crop

Management organized by International Potato Center (CIP) for Innovation

Platform (IP) members of Kadahenda, Rwanda.

Murakoze cyane

For more information, please contact/ Ukeneye ibindi bisobanuro, wabaza Jean Claude Nshimiyimana:

Email: J.Nshimiyimana@cigar.org; cnshimiye@gmail.com

Phone: (+250) 788-500-053/ 788-639-417

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