Impacts of Wheat Stripe rust in Morocco: Breeding and Control Strategies
Impacts of Wheat Stripe rust in Morocco : Breeding and Control Strategies RAMDANI et al. INRA Morocco
Total population in Morocco 34.4 millions (2008) Source : CIA World Factbook
The economy of Morocco is based to a large extend on agricultural production. that contribute with 16 to 20% of GDP (Gross domestic product). Cereals (wheats and barley) are among the major crops. They are cultivated over more than 60% of the cropped land each year (around 6 millions hectares) . However Yields remain low due to biotic and abiotic stresses . Crop losses caused by pests of cereals are estimated at 30% or more. Some of these key pests include: Rusts (Leaf and stripe rusts) , Septoria, Root rots and Hessian fly.
Cereal production in Morocco during 2008-09 and 2009-10 cropping seasons Source: ONICL
Consumption of cereals in Morocco during 2000-01 (average 197.4) (World average : 152 kg/year/capita) Source: Direction des statistiques
Moroccan imports of Cereal during 2006-07 and 2007-08 Source: ONICL
To address these problems of biotic stresses and to boost the food security strategy, the development and implementation of a broad based diseases management strategy is required. This should be based on the increased use of resistant cultivars, and the enhancement of the durability of resistance through appropriate gene management systems, complemented by other control methods, such as selective use of fungicides and cultural practices INRA Morocco is carrying out many activities mainly surveillance, screening of sources of resistance, tracking the effectiveness of known genes, incorporating resistant genes. To speed up the incorporation of resistance to rusts, namely the stripe rust, marker-assisted selection is being adopted at the early stages of the breeding program to introgress resistance to yellow rust along with other traits of agronomic interest. Fully aware of the magnitude of threat of the rust diseases to national cereal production and in order to formulate and implement national strategies to prevent such threat, INRA-Morocco organized two workshops during 2010, one on “ Importance of rusts of wheat in Morocco and strategies for controlling and preventing their losses ” and the second on “Wheat Rust Diseases Awareness and Contingency Planning”. These workshops were attended by representatives of key national research, extension and production institutions involved in cereals, and of FAO and ICARDA.
Status of wheat diseases in Morocco Screening for multiple diseases resistance and agronomic performance On Farm Conservation and Mining of Local Durum and Bread Wheat Landraces of Morocco for Biotic Stresses and Incorporating UG99 resistance Effectiveness of Yr genes Quantification of yield losses due to foliar diseases
2007-08 Prevalence of wheat diseases in Morocco during 2007-08 2008-09 and 2009-10 cropping seasons 2008-09 2009-10
Surveillance of wheat diseases in Morocco (2008-09) Bread wheat Durum wheat 80 & 44 BW & DW fields were inspected The survey revealed that : SLD, LR & YR were the most prevalent both on B W & DW. The same trend was reported except for YR that was more prevalent than in previous seasons and was detected in almost all wheat growing areas . This fact might be due to the emergence of new virulent races and the lost of effectiveness of Yr27 reported by Ramdani et al. (2009) and confirmed during this season LR was observed on the totality of inspected DW fields across all areas and its prevalence on BW ranged from 50% in Sraghna and Taza to 100% in Abda, Rhamna and Tadla. The prevalence of YR on BW ranged from 41% in Chaouia to 100% in Saïs and Sraghna.
Surveillance of wheat diseases in Morocco (2009-10) 53 & 19 BW & DW fields were inspected The survey revealed that : SLD, LR & YR were the most prevalent both on B W & DW. The same trend was reported except for YR that was more prevalent than in previous seasons and was detected in almost all wheat growing areas . This fact might be due to the emergence of new virulent races and the lost of effectiveness of Yr27 reported by Ramdani et al. (2009) and confirmed during this season
Quantification of yield losses due to foliar diseases Afourar experimental station, 2009-2010
Evaluation of diseases severity 20 days after treatment Afourar INRA experimental station, 2009-2010
Severity of main diseases on bread wheat ACHTAR 40 days after treatment and grain yield 16.4% 47.4%
Effectiveness of Yr genes under Mekn è s conditions during four consecutive growing seasons * : Missing data for Morocco during 09 and for Jupateco, Yr24, Yr26 and Yr32 during 06, 07 and 08 The highly effective Yr genes were Yr 1, 5, 10, 15 and YrSp .
Effectiveness of Yr genes under Mekn è s , Douyet and Annoceur conditions during 2006-07 and 2007-08 growing seasons
Effectiveness of Yr genes under Marchouch and Annoceur conditions during 2009-10 growing season The highly effective Yr genes were Yr 1, 5, 10, 15 and YrSp .
Effectiveness of Lr genes under Moroccan conditions
Effectiveness of Lr genes under Marchouch and A. Tazi conditions during 2009-10 growing season The highly effective Lr genes were Lr 9, 17, 19, 28 and 30 .
Re a ction of so m e bread and durum wheat v arieties towards leaf and stem rusts diseases at Douyet during 2008-09 Evaluation was made towards the end of May 09. BW1 to BW5 stand for Bread Wheat varieties that are respectively Arrihane, Amal, Achtar, Marchouch and Kenz. DW1 to DW5 stand for Durum Wheat varieties that are respectively Isly, Marzak, Tomouh, Marjana and Vitron Amal (BW2) and at some extent Marjana (DW4) and Vitron (DW5) exhibited a good level of resistance to stem rust. Stem rust despite being rare in recent years, may become a real threat given its past history in the country and the emergence of new virulent races such as Ug99 and its lineages
La nouvelle race virulente de la rouille noire (Ug99) : Le Maroc n’est pas en abri
Stem rust (Puccinia graminis f.sp. tritici) : Real threat
Les maladies cryptogamiques des blés Yellow (Stripe) rust (Puccinia striiformis)
What would be the effect of diseases on yield and its components mainly TKW Afourar INRA experimental station 2009-2010
Idiotype breeding Biotic constraints Abiotic constraints Pests Diseases Genetic of resistance Epidemiology Host x Pathogen Intraspecific variability of the pathogen Agronomic traits <ul><ul><li>Quality traits </li></ul></ul>IPM Management practices Yield potential/stability Tolerance to Drought, heat, cold , …. Figure : Interdisciplinary approach for an ideotype breeding