Research prepares maize breeding programmes for future climates

A. Wangalachi (CIMMYT)

Outcome year

Led by

CIMMYT

Regions

Summary 

Research of the International Maize and Wheat Improvement Center (CIMMYT) has informed the agenda of maize breeding programmes in sub-Saharan Africa, to ensure that new varieties developed will be tolerant to heat stress as well as drought. CIMMYT’s climate projections for maize-producing areas in sub-Saharan Africa highlighted the increasing prevalence of heat stress and identified hotspots of vulnerability. Researchers analysed commercially available maize varieties and new drought tolerant varieties developed under the Drought Tolerant Maize for Africa (DTMA) project, by phenotyping and modelling crops under expected future climates. The results highlighted the susceptibility of these varieties to increased heat stress. The research also identified potential yield gains that could be made through adapting the existing breeding pipeline to address the potential effects of future climates, particularly heat stress.

Engaging with breeding initiatives in the region, CIMMYT has informed changes to existing policies focused on breeding drought tolerant varieties, to also incorporate heat tolerance. These initiatives include:

  • Crop Breeding Institute (CBI), Government of Zimbabwe: CBI had been breeding maize varieties for drought tolerance in the country’s drought-prone natural regions, but as a result of CIMMYT research showing that heat- and drought-tolerance are only weakly correlated, the Institute decided that in the future, varieties should be screened for heat- as well as drought-tolerance. CIMMYT is now working with CBI to complement this work and screening already-released varieties and those that are about to be released to assess whether they are both drought- and heat-tolerant.  
  • Drought Tolerant Maize for Africa (DTMA) Initiative: The DTMA initiative develops drought tolerant maize varieties in 13 African countries. Based on CIMMIYT’s work on heat tolerance, the initiative is now breeding maize varieties for heat and drought tolerance. 
  • Private sector seed companies: Seed companies in the region such as Progene, AgriSeeds, SeedCo and Pannar are appreciative of CIMMYT’s work on heat tolerance, and have expressed interest in using CIMMYT maize germplasm that is heat- and drought-tolerant to develop new varieties . 

Key facts 

  • CIMMYT’s research indicates that drought-tolerant maize varieties may not withstand increase in temperatures 
  • CIMMYT is informing the policies of the Crop Breeding Institute, Zimbabwe and DTMA to develop varieties which are heat and drought tolerant  

Lessons: key elements of success 

  • Developing heat and drought tolerant varieties is an effective way of dealing with multiple challenges of climate change 
  • Addressing potential weaknesses in breeding strategies for drought-tolerant maize saves resources at many levels  
  • Engagement with national, regional, and private sector partners enables scaling up of efforts 

Further reading 

Related research outputs