theme – 3 wheat improvement for the changing climate: adaptation to heat stress environments
TRANSCRIPT
Wheat Improvement for the Changing Climate:
Adaptation to Heat Stress Environments
Izzat S. A. Tahir
ARC/ICARDA
International Workshop on: “Applied Mathematics and Omics Technologies for Discovering Biodiversity and Genetic Resources for Climate Change Mitigation and
Adaptation to Sustain Agriculture in Drylands”
Rabat - Morocco, 24-27 June 2014
Outlines
• Climate change and its effects on wheat production
• Breeding strategy and methodology
• Wheat improvement for heat tolerance
• Broadening the wheat genetic diversity
• Crop management
• Integrated approaches
• Precision Phenotyping Platforms
• Conclusions
Abstract
Breeding high-yielding wheat varieties adapted to diverse environments is regarded as one of the most important means needed to meet the ever increasing global demand for wheat especially in the light of the ensuing climate change. Genetic improvement of wheat yield could be through a better exploitation of genetic diversity, understanding and mining physiological traits associated with climate change and then utilization these traits via their introduction into new varieties by conventional breeding and/or genetic manipulation. Multiple synthetic derivatives (MSD) developed by Tottori University utilizing diverse sources of Aegilops tauschii are being evaluated for heat stress tolerance in Sudan. Multi-location evaluation and selection is essential for identifying high-yielding better adapted wheat varieties. In this respect, close collaboration, coordination and communication are needed among the national (NARS), regional and international wheat research centers and scientific community. One of the good examples for such collaboration between NARS and international center is wheat improvement under heat stress condition coordinated by CIMMYT/ICARDA. In this regard, wheat germplasm targeted to heat stress areas is evaluated and selected under temperature gradients ranging from favorable to very high temperatures. Some stress adaptive traits have been identified and could be used for further improvement and mining the genetic resources for heat stress tolerance. Promising lines identified have been shared among west and east African low lands experiencing high temperature during the growing season. This is further supported by the plan to set up Precision Wheat Phenotyping Platforms (PWPPs) anticipated to improve the breadth and quality of data collected and shared among wheat scientists.
Climate change and its effects on wheat production
• Increased frequency of: • Heat stress,
• Droughts
• Flooding
• Reduced crop yields.
• Food insecurity due to extreme climate events
• Countries with less wealth and natural resource adapt less efficiently to climate change
IPCC, 2007
Climate change and its effects on wheat production, cont.
• Global warming: • Could be beneficial for wheat in some regions,
• Could reduce productivity in zones where optimal
temperatures already exist.
• How to adapt and mitigate the climate change effects:
• Germplasm development
• Crop management
• Mitigation
(Climate change: Can wheat beat the heat? (Ortiz et
al. 2008).
Figs. Adapted from Lobell et al. 2008. Science , 319: 607-610
Breeding Strategy and Methodology
• Broadening the genetic base and enhancing variability:
Locally adapted cultivars
Landraces
Wild relatives
Derived synthetic wheat
Winter wheat gene
Breeding Strategy and Methodology, cont.
• Strategic trait-based crossing to address different objectives:
Yield potential
Biotic stresses
Abiotic stresses (e.g. Heat stress)
Grain quality
Bringing drought and heat adaptive traits together in one genotype could increase wheat yields particularly in low yielding environments. Lopes et al. 2012. Field Crops Res. 128:129–136
Breeding Strategy and Methodology, cont.
• Biotech Tools: • Doubled haploid
(Anther/microspore culture)
• Molecular Breeding
Multi-environment testing and evaluation • Yield potential
• Breeding for Abiotic Stress Tolerance:
• Cold
• Drought
• Heat stress
Attempts to expand wheat into heat-stressed
areas in Central Sudan from 1918-1940 failed
due to the lack of: Adapted cultivars
Appropriate cultural practices
Intensified wheat breeding in collaboration with CG Centers resulted in the release of several heat stress tolerant cultivars,
The major outcome was the expansion of wheat to new heat-stressed areas.
An example
The genetic gain in grain yield under the heat stress
environment of Sudan was estimated to be 30.2 kg/ha/year
Tahir et al. 2000
Wheat improvement for heat tolerance
Wad Medani
Dongola
Sids
Screening and Selection for Heat Tolerance: Temperature gradient
Mean temperatures (0C) during crop season (LTA)
28.9
20.8
16.4
0 20 40
Wad Medani,Sudan
Dongola, Sudan
Sids, Egypt
Days to heading and grain yield across sites
8860
5250
3540
89
68
59
40
50
60
70
80
90
100
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
Sids(Egypt)
Dongola(N Sudan)
WadMedani (C
Sudan)
Grain yield (kg/ha)
Days to heading
Screening/Selection for heat tolerance: Hot spots
• Advanced lines and
segregating populations (F3-
F6) evaluated at Wad Medani,
Sudan.
• Visual selection have been
made
• More than 65% of visually
selected lines were of high
yield
Materials received from CIMMYT, ICARDA + National Program evaluated and selected under temperature gradients
/
• Selected elite lines redistributed to different East and west African countries involved in SARD-SC Wheat Project
• Promising and encouraging results obtained
Partners countries expressed their
satisfaction with the material received and evaluated
A number of entries have been frequently
selected by partners form the nurseries received
Some lines selected across several environments
Preliminary Results (2013/2014 Season):
REYNA-28
REYNA-29
JNRB.5/PIFED
KINGBRD#1//INQALAB91*2/TUKURU
HUBARA-3*2/SHUHA-4
HUBARA-16/2*SOMAMA-3
KAUZ'S'/FLORKWA-1//GOUMRIA-3
SERI.1B*2/3/KAUZ*2/BOW//KAUZ/4/ANGI-2
ATTILA 50Y//ATTILA/BCN/3/STAR*MUSK-3
SERI.1B*2/3/KAUZ*2/BOW//KAUZ/4/KAUZ/FLORKWA-1
Most frequently selected lines/families:
More studies at molecular level:
• Association Mapping Panel (GRDC Project)
• WAM I
• Physiological and Molecular Breeding
Broadening the wheat genetic diversity for abiotic stress tolerance (Multiple Synthetic Derivatives, MSD
Tsujimoto et al.
• Genetic diversity of diverse 51 accessions of Aegilops tauschi was analyzed using DArT markers.
• The accessions were crossed with a durum wheat to produce 51 amphidiploids designated as primary synthetics
• Each primary synthetic line was crossed with ‘Norin 61
Stress adaptive traits
Canopy temperature Fig. adapted from Pask et al . 2012
Ground cover Fig. adapted from Pask et al . 2012
Stomatal conductance
Key developmental (phenological) stages
NUT
H2O
CHO
CHO
Stem Reserve Remobilization
NUT
H2O
Crop management
• Raised bed planting
• Conservation Agriculture
• New Irrigation systems
More approaches
• Mathematics, Omics and Modeling
• Network s
• Facilities
• Platforms for integrated solution
Credit agencies
Trader/marketer
transporter
NGOs
Farmers
Government policies, Informal institutions, practices, behaviors and attitudes
NARS
Extension
agencies
Education
and training
organizations
Development
agencies
SARD-SC Wheat
Research teams
Local and
regional
decision
makers
Service providers
Manufacturers
IAR4D and Innovation Systems: Innovation Platform
Precision Phenotyping Platforms
• Precision Wheat Phenotyping Platforms (PWPPs) anticipated to:
• Improve the breadth and quality of data collected
• Data and knowledge shared among wheat scientists.
• Wad Medani, Sudan is proposed as PWPP for heat stress
Conclusions • Better exploitation of genetic diversity,
understanding and mining physiological climate change-adaptive traits and their utilization .
• Multi-location testing is important for spatial adaptation and identification of temporally stable, stress tolerant germplasm
• Evaluation at hot spots has resulted in the development of several promising lines tolerance to abiotic stresses
• Broadening the wheat genetic diversity
• Networking and international collaboration
• Platforms for Integrated solution