Pathotypic Evolution of Yellow (Stripe) rust in CWANA (1998-2008).

Amor Yahyaoui,Senior Cereal Pathologist, ICARDA

Coordinator, ICARDA-CIMMYT Wheat Improvement Program

Safiq Hakim,University of Aleppo, Syria

Mogens HovmollerAARHUS University (DIAS), Denmark

The potential impact of wheat yellow (stripe) rust is particularly serious in Central West Asia and East Africa (CWANA) and could become a serious problem in North Africa and even in Europe

Yellow (Stripe) Rust: Clear & Present Danger

Wheat Yellow (Stripe) RustPuccinia striiformis fsp tritici

(Pst)

Most common and widespread rust disease of wheat

in CWANA

Stripe rust highly destructive but not well understood disease. Pst could threaten food

security in many countries in CWANA

M.Hovmoller et al. , DIAS, DK

In Syria: 20-70 % yield loss;

Iraq: >40% yield loss;

Turkey: >20% yield loss + 2-3 fungicide appl; Important losses recorded in Algeria, Azerbaijan,

Ethiopia, Morocco, Uzbekistan, …

2010 Yellow rust epidemic

Susceptible mega.Variety.”Cham 8”

“New” Race-Vir Yr27 + High Inoculum load

Favourable Climate Agro.Practice

(high seeding, Fertilizer Rates)Irrigation...

2010 Yellow Rust Epidemic in Syria

Where did the stripe rust (Pst) inoculum came from?

Why was it so severe?

Epidemics caused by many changes:

Crop management

Changes in cultivars-large areas grown to susceptible varieties

Climate

Change in pathotypes (new & virulent races)

Green Bridge & Rust Spore Migration

Factors attributed to the host, the pathogen, and the environment affect the development of Pst rust epidemics in CWANA

Changing World

Trans-boundary pest

Desert Locust vs. Rusts

ICWIP

Gate for

West-East

rust spore

Movement

Green Bridge:Wheat crop all Year Important overlap periods in East Africa, Yemen, CWA

Green Bridge

What if no wheat in Yemen Nov-June?Off season wheat croppingIrrigated wheat (small areas +/- 20,000ha)Regulated fungicide use

A source of Pst inoculum is necessary to initiate an epidemic;

Pst fungus must successfully over summer in the area to provide a continuous supply of spores, or goes through an alternate host;

Green Bridge & Rust Spore Migration

D. Hodson-AGPP/FAO ; BGRI

Large quantities of spores must blow in from another area soon enough for an epidemic to get an early start.

Year Country Pathotypes (Physiological races)

2001 Syria 6 E 16 6 E 36 38 E 150 70 E 130 230 E 150

2002 Syria 0 E 16 2 E 18 102 E 150 238 E 134 166 E 158

2002 Syria 166 E 150 230 E 150 238 E 150 119E60

2003 Syria 0 E 0 0 E 2 0 E 8 2 E 0 0 E 16

2003 Syria 0 E 18 32 E 0 0 E 28 4 E 12 12 E 6

2003 Syria 4 E 16 46 E 46 65 E 6 15 E 166 14 E 134

2003 Syria 14 E 190 247 E 16 32 E 130 78 E 130 255 E 112

2003 Syria 128 E 148 199 E 132 134 E 134 230 E 222 175 E 150

2004 Syria 206 E 22 84 E 2 68 E 98

2006 Syria 4 E 0 10 E 32 182 E 16 191 E 163

2007 Syria 0 E 0 3 E 0 0 E 3 4 E 0 32 E 0

2007 Syria 98 E 3 64 E 49 103 E 5 140 E 5 32 E 135

2007 Syria 79 E 124 229 E 26 111 E 215 64 E 159 189 E 48

2007 Syria 101 E 128 129 E 52 54 E 248 204E 76

Highly Effective YRG: (5); (15); (3b,4b); (SP)

Effective YRG: (CV); (10); (1)

Evolution/changes in Pst pathotypes (races)in Syria

Yea Country Pathotypes (Physiological races )

2002 Lebanon 238 E 134 166 E 158 238 E 190 0 E 8

2003 Lebanon 0 E 14 31 E 150 173 E 206 166E158

2005 Lebanon 204 E 76

Yr*: SO, “3b,4b”, CV, 5, 15, SP

2001 Yemen 230 E 12 4 E 40 38 E 4 119 E 60

2005 Yemen 22 E 245 137 E 158 128 E 143 0 E 128 4 E 190

2001 Iraq 230 E 44

2007 Tunisia 38 E 18

Evolution/changes in Pst pathotypes (races) in Lebanon and Yemen,

Yr*: Effective Resistance Genes

Common Virulence patterns

M.Hovmoller et al. , ARHUS, DK

Effective/ineffective Resistance Genes: Avocet-Isogenic Lines

Virulent Avirulent Race

6,7,8,9,11,12,17,18,27,A / 1,5,10,15,SP 422 E 158

6,7,8,9,11,18,27,A / 1,5,10,12,15,17,SP 7 E 150

7,8,9,11,18,27,A / 1,5,6,10,12,15,17,SP 7 E 150

6,7,8,9,12,17,18,27,A / 1,5,10,11,SP 110 E 182

6,7,8,9,11,12,17,18,A / 1,5,10,15,SP,27 129 E 52

1,6,8,9,10,11,15,17,18,27,A / 5,7,12,SP 101 E 128

6,7,8,9,10,11,17,18,27,A / 1,5,12,15,SP 22 E 245

6,7,8,9,11,12,17,18,27,A / 1,5,10,15,SP 137 E 158

6,7,8,9,11,12,17,18,27,A / 1,5,10,SP,27 128 E 143

6,7,8,9,11,12,17,18,27,A / 1,5,10,15,SP 4 E 190

Virulent Avirulent Race

Important resistance genes widely used in breeding programs have lost their effectiveness (Yr1, Yr 6, Yr7, Yr9, Yr17, Yr18, Yr27)

Other are breaking down in parts of the region (Yr15, Yr10, …)

Few Yr. RG still effective in CWANAYr 5, Yr “3b,4a” (Hybrid 46) , Yr Sp

Effective Yellow Rust Resistance GenesYr-RG

Genotypes R-GenesSeedling Gr.Stg Adult Gr. Stg

R S %R %S R S %R %S

Yr 5/ 6* Avocet S 5 63 0 100 0.0 108 5 96 4

Hybrid 46 3b,4b 63 0 100 0.0 84 5 94 6

Yr Sp / 6* Avocet S SP 63 0 100 0.0 91 7 93 7

Effectiveness of Yr-RG at seedling and adult growth stages

GenotypesR-

Genes

Seedling Gr.Stg Adult Gr.Stg

R S %R %S R S %R %S

Yr 15/ 6* Avocet S 15 62 1 98.4 1.6 82 7 92 8

Cham 1 DW 63 0 100 0.0 72 6 92 8

Yr1/ 6*Avocet S 1 61 2 96.8 3.2 59 24 71 29

Yr 10/6* AvocetS 10 58 5 92.1 7.9 49 29 63 37

Yr Sp/6* AvocetS SP 63 0 100 0.0 91 7 93 7

Effectiveness of Yr-RG at seedling and adult growth stages

Genotypes R-Genes

Seedling Gr.Stg Adult Gr.Stg

R S %R %S R S %R %S

Reichersberg 42 7+ 29 34 46.0 54.0 57 9 86 14

Vilmorin 23 3a,4a+ 48 15 76.2 23.8 25 0 100 0

Nord Despres 3a,4a 47 16 74.6 25.4 24 1 96 4

Yr 8/ 6* Avocet S 8 22 41 34.9 65.1 40 23 63 37

Carstens V CV 52 11 82.5 17.5 97 2 98 2

Effectiveness of Yr-RG at seedling and adult growth stages

Effectiveness of Yr-RG at seedling and adult growth stages

Seedling Stage Adult Stage

GenotypesR-

Genes R S %R %S R S %R %S

Yr 18/ 3* Avocet S 18 28 35 44.4 55.6 9 60 13 87

Jupateco R 18+ 23 40 36.5 63.5 25 44 36 64

YrSk / 3* Avocet S 27 50 13 79.4 20.6 12 41 23 77

Yr 17/ 4* Avocet S 17 34 29 53.9 46.1 25 36 41 59

YearDefeated Gene Combinations Races

2003 Yr9, Yr27Yr18

199 E 132

2006 137 E 158

2007 101 E 128

Year Defeated Gene Combinations Races

2003Yr8, Yr18Yr9, Yr27

31 E 150

2004 110 E 182

2005 54 E 248

2006 22 E 245 4 E 190 128 E 248

Recent Defeated Resistance GenesBroad spectrum Pst races

Year Defeated Yr 10 Gene

(location)Races

2003 Syria 255E112 247E16

2003 Lebanon 31E150

2005 Yemen, AzerbaijanPst. Isolates virulent on durum wheat (seedling growth stage)

2006 Syria 191E163

2007 Syria 189E48

Defeated Yr10 across the regionPst. Virulent on durum wheat

Under favourable weather conditions;

Potential of wheat yellow rust epidemics

from new emerging virulent rust (Pst) races

Remains a real threat to the wheat

producing countries

WheatWheat

Partnerships & Communications

Regional Yellow rust ConferencesIran 2001: SPII & R.Johnson (>200 P) $ Iran, ICARDA, CIMMYT”

Pakistan 2004; PARK & O.Abdalla (>150 P) $ ACIAR, DANIDA, ICARDA, CIMMYT

Uzbekistan 2006: PFU & S.Rajaram (> 80 P) $ ACIAR, DANIDA, ICARDA

Turkey 2009: TAGEM & O.Mamluk (> 100 P) $ FAO, AFESD, ICARDA, CIMMYT

Syria 2013: ICARDA &….

Acknowledgment

NARS Collaborators: Rust Networks

NVRS: Egypt, Ethiopia, Sudan & Yemen, Eritrea

West Asia: Turkey, Iran, Syria, Lebanon, Pakistan

Central Asia & Caucasus: Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, Tajikistan

North Africa: Algeria, Morocco, Tunisia

Advanced Research Institutions & UniversitiesDIAS, & KVL-DenmarkPBI, AustraliaWSU, MSU- USAUniv. Aleppo & Damascus, Syria

Research SupportICARDA-Maha,Munzer, ShafiqDIAS: Ellen, AnneMarie-DK

SPII: Torabi et al- IranCREFCI; Lutfi et al..- TurkeyEIAR: Ayele et al--EthiopiaARC: Sherif et al---Egypt

IAV: Ezzahiri et al-- Morocco

DonorsIFAD (NVRS)DANIDA (IDM)ACIAR AFESD (Rust Mgt)FAO (LoA’s)

ContributorsICARDACIMMYTSPIIDIAS, Flak

Thank You