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 SorghumArea harvested of sorghum Intensively grown in the borders between Niger and Nigeria and in West India è Which are areas of high suitability Current sorghum suitability Monfreda et al., 2008 Ramirez-Villegas et al., 2011
4 • 3/21/11 What s the principal constraint for Sorghum?Sorghum x: Sorghum n:Genotype of high Genotype of lowtemperature is temperature issensitive to sensitive to 2 main current climatic constraints
5 • 3/21/11 Sorghum suitability changes by 2030 Central Ethiopia Uganda SE Kenya TanzaniaNegative impact: Central Ethiopia, Uganda, SE Kenya, Tanzania è 50-80% of suitability area could decrease in climatic suitability
6 • 3/21/11 Adaptation before negative impacts 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.
7 • 3/21/11 Banana One of the world s major food cropsCurrent banana suitability Where banana suitable? Most suitable area located in tropical humid regions ⇒ Coinciding with the current distribution of the crop ⇒ Low lands in Latin America,Area harvested the Caribbean, western Africa, RDC, CAF and in southern Asia
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 positively impacted Prediction of Area negatively impactedArea limited by min temperature and rainfall will be favored - South Americain the future - West and central Africa è East Africa, Southern Africa, Sub-tropical Brazil, è Decrease of banana suitability due toParaguay, Northern Argentina,… drought è Projected climate of the 2020s is expected to favor è Poor fruit developmentincreased 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 bananasHOWEVER CC couldhave positive impactto reduce BlackSigatoka. BlackSigatoka will be lesssuitable in the mostareas
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 Potential breeding strategies • 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 Drought resistance and heat tolerance • Breeding heat tolerance into bean = Important objectives for genetic improvement – 7.2 million ha of current bean area more suitable – Increase highly suitable areas by some 54% 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.
15 • 3/21/11 Potential breeding strategies • 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 Tepary bean
16 • 3/21/11 Beans and CC impact on fungal, viral disease and insect pests • 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
17 • 3/21/11 Potential for crop improvement • 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
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 Comparison of changes in crop suitability in specific site 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
20 • 3/21/11 Comparison of changes in crop suitability in specific site 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