breeding strategies
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Breeding strategies workshop Ethiopia 6-8th of December 2011TRANSCRIPT
1 • 3/21/11
Breeding strategies
Workshop Ethiopia 6-8th of December 2011
2 • 3/21/11 Breeding strategies on which crops?
Sorghum
Bean
Banana
3 • 3/21/11
Monfreda et al., 2008
Intensively grown in the borders between Niger and Nigeria and in West India è Which are areas of high suitability
Sorghum Area harvested of sorghum
Current sorghum suitability
Ramirez-Villegas et al., 2011
4 • 3/21/11 What’s the principal constraint for Sorghum?
2 main current climatic constraints
Sorghum n: Genotype of low temperature is sensitive to
Sorghum x: Genotype of high temperature is sensitive to
5 • 3/21/11 Sorghum suitability changes by 2030
Negative impact: Central Ethiopia, Uganda, SE Kenya, Tanzania è 50-80% of suitability area could decrease in climatic suitability
Central Ethiopia
Uganda
Tanzania
SE Kenya
6 • 3/21/11
Simple strategies of adaptation to minimize sorghum yield losses – Delayed sowing to avoid water stress – Crop substitution – Expansion to new agriculturally suitable areas since some environments with
particularly low temperature will likely become suitable in the future, such as the highlands of the semi-arid tropics.
HOWEVER
Biological adaptation of Sorghum are needed - The sorghum genetic pool contains a wide range of traits - Important abiotic traits in terms of sorghum adaptation in Sub-Saharan Africa and
India: growing cycle duration and drought tolerance.
Adaptation before negative impacts
7 • 3/21/11
Where banana suitable? Most suitable area located in tropical humid regions
⇒ Coinciding with the current distribution of the crop
⇒ Low lands in Latin America, the Caribbean, western Africa, RDC, CAF and in southern Asia
Area harvested
Current banana suitability
Banana One of the world’s major food crops
8 • 3/21/11 What’s the major climate constraints for banana?
: up to 20% of global suitable areas: N India, N Myanmar, Laos, N Vietnam, S Africa Limited by low rainfall: Atlantic coast of Latin America, northeastern Brazil, the Sahel, central Tanzania Major climate constraints in most areas =
WAF: West Africa, EAF: East Africa, CAF: Central Africa, IGP: Indo-Gangetic plains, AML: Latin America
9 • 3/21/11 How will change the suitability of banana in the future?
Prediction of Area negatively impacted - South America - West and central Africa è Decrease of banana suitability due to
drought è Poor fruit development
Prediction of Area positively impacted Area limited by min temperature and rainfall will be favored in the future è East Africa, Southern Africa, Sub-tropical Brazil, Paraguay, Northern Argentina,… è Projected climate of the 2020s is expected to favor increased banana production in some areas by up to 50%.
10 • 3/21/11 How adapting the sector to climate change?
- Measures to manage impacts need to involve agronomic practices as well as the development of more resilient hybrids and with fruit quality that is acceptable to markets è Increased tolerance of drought and temperature extremes,
- Banana resistant to Black Sigatoka which is the most widespread disease of bananas
HOWEVER CC could have positive impact to reduce Black Sigatoka. Black Sigatoka will be less suitable in the most areas
11 • 3/21/11 Bean The most important food legume in tropical Latin America
and East and southern Africa
Area harvested
Current bean suitability
12 • 3/21/11 Which climatic constraint affects the most beans?
Major climate constraints: heat stress drought stress
13 • 3/21/11 Changes in Beans Suitability
• Average global area of suitability for growing beans may be reduced by 6.6% by 2020 • But wide range of change in suitability from -87% to +66% across regions.
14 • 3/21/11
• Breeding drought resistance into bean – 3.9 million ha of current bean area more suitable – 6.7 million ha currently not suitable would be suitable
• Breeding heat tolerance into bean – 7.2 million ha of current bean area more suitable – Increase highly suitable areas by some 54%
Potential breeding strategies
Expected impacts of breeding technologies in bean. Reduced susceptibility to drought (left) and improved heat tolerance (right) were found to have the greatest impact on suitable, marginal and unsuitable areas.
Drought resistance and heat tolerance = Important objectives for genetic improvement
15 • 3/21/11
• Adaptation to drought stress – Fitting the right root system to each production environment:
Deeper root system – Root whorls – basal root è Improved genotypes with vigorous root systems
– Stomatal control – Improved photosynthate remobilization under stress
• Adaptation to heat stress
– Tepary bean “Sonora 32” (P. acutifolius) = more tolerant of high temperature at germination
Potential breeding strategies
Tepary bean
16 • 3/21/11
• Changes of precipitation and temperature can lead to the emergence of some diseases and alter the distribution and severity of pathogens and diseases
• Increase in precipitation in many African countries for the 2020s: - Beans more affected by angular leaf spot (caused by Phaeoisariopsis
griseola): Rwanda, Burundi and some regions of Tanzania, Uganda, Kenya, and Malawi
- Beans could be more affected by anthracnose (caused by Colletotrochum lindemthianum): Rwanda, Burundi, Kenya
- Root rot disease ( Pythium and Fusarium spp.): Rwanda, Burundi, Kenya, and Uganda
• Regions affected by drought
- Less prone to attack from fungal pathogens
• Whiteflies- regions affected by whiteflies - Find bean germoplasm resistant to whiteflies
Beans and CC impact on fungal, viral disease and insect pests
17 • 3/21/11
• Research in Breeding for drought-resistant beans: CIAT-Colombia, EMBRAPA-Brazil, INIFAP-Mexico, Zamorano-Honduras è Mesoamerican gene pool, study based on grain yield under stress è Primary source of genes for drought resistance = Race Durango è Race G21212 express substantial remobilization of photosynthates to grain
under drought + well-filled grain under stress
• Common bean genotypes adapted to heat stress: G122, G5273, BAN26, Brio, CELRK, HT20, Venture, Negro Argel è But need better yield è High temperature tolerance may be the biggest
challenge of adapting to climate change
è For now: tepary bean (P.acutifolius) have the most useful traits for drought and high temperature
Potential for crop improvement
18 • 3/21/11 Comparison of changes in crop suitability in specific region
West Africa: Changes in suitability of Sorghum are positive => Potential adaptation= focus on sorghum crop è Need genetic improvement for Banana and Bean
19 • 3/21/11
Uganda: Changes in suitability of Banana are positive => Potential adaptation= focus on banana crop in this area è Need genetic improvement for Bean and Sorghum
Comparison of changes in crop suitability in specific site
20 • 3/21/11
Indo-Gangetic Plains: Any of the 3 crops would be positively impacted by CC è Need to find other crops or search other type of variety which would be suitable in the future climate
Comparison of changes in crop suitability in specific site