Mitigate the effect of high temperatures on maize productivity

Extraordinary Call
USD 500.000
Counterpart Amount:
USD 793.888
Execution time
36 Months
Total Amount:
USD 1.293.888
Participating countries:
Spain Spain Argentina Argentina Mexico Mexico
Funding source:
FONTAGRO Amount 39% Other agencies 0% Counterpart Amount 61%

Executive Summary

Maize is one of the main sources of food for a high proportion of the region's population. Climate change will cause increases in temperatures that can negatively affect maize productivity in Latin America. Yield sensitivity to temperature (alone or associated with water or nutrient stress) is generally much higher if stress occurs during the period around flowering (which determines the number of grains per plant) or during the filling of the grains (which affects the final weight of the grains). However, the physiological causes that generate these effects on productivity have not been clearly elucidated, nor has been determined the  genotypic variability that could be useful in this context in breeding programs.

The general objective of the project was to identify genetic and environmental factors of the susceptibility of maize productivity to high temperatures that can be useful both in genetic improvement and in the design of agronomic practices. Specifically:

  1. elucidate the physiological origin of the effects of high temperatures on maize productivity;
  2. determine the variability of the maize response to high temperatures;
  3. quantify the effects of nitrogen fertilization and the application of an ethylene inhibitor in reducing susceptibility to high temperatures;
  4. disseminate the scientific results to farmers and breeders of private companies in the region, as well as to the scientific community in general.

The technological solution

The high temperatures resulting from climate change can negatively affect maize production. The project contributed to improving the understanding of the effects of high temperatures on the phenological stages of cultivation and productivity, highlighting the importance of the effects during flowering and therefore on the number of grains produced per plant.

It also contributed to identify progenitors that can be used as potential donors of tolerance and the molecular markers that were significantly associated with the best behavior of maize against stress.

Likewise, it identified the importance of regulating nitrogen fertilization, since an excess could exacerbate the effects of high temperatures, while a deficiency would generate yield losses obtainable in the event of severe thermal stresses.


  • High temperatures have more deleterious effects during flowering and not during the filling of the grains, so the greatest effect of heat stress is on the number of grains.
  • There is wide genotypic variability in tolerance to heat stress (and to the combination of heat and water stress). Molecular markers associated with this tolerance and parents of future crosses aimed at improving this tolerance were identified.
  • The possibility of using the Normalized Difference Vegetation Index (NDVI) as a selection criterion associated with the maintenance of fresher and consequently greener vegetation cover under stress conditions was also identified.
  • Growth regulators related to ethylene metabolism appear to be promising as a tool to mitigate the effects of heat stress.
  • Over fertilization generates a marked increase in heat stress susceptibility, so future fertilization recommendations should be made with greater precision.
  • The project generated 11 publications in indexed scientific journals, 15 presentations at international scientific meetings, 10 courses, 12 talks; and four Agricultural Engineer, two  master’s and three doctorate theses.


The main direct beneficiaries were the hundreds of researchers, professionals, and students who participated in project activities, including the numerous courses, talks, conferences, and scientific publications.

Thousands of maize producers could benefit indirectly through the incorporation of the knowledge generated in the project in genetic and agronomic improvement programs in the countries.

Sustainable Development Goals

Climate action Partnerships for the goals

Main donors

Participating Organizations

  • Universidad de Lleida (UdL) - España
  • Universidad de Buenos Aires (UBA) - Argentina
  • Centro Internacional de Mejoramiento de Maíz y Trio (CIMMYT) - México

Graphics and data

Financing by country (in USD)
FONTAGRO Amount Other agencies Counterpart Amount

Geolocated Map


Project leader Spain

Gustavo Slafer Lago


Maria Elena Otegui


Jill Cairns


Mateo Vargas

With the support of
Fondo Coreano de Alianza para el Conocimiento en Tecnología e Innovación (KPK)