Heat Stress Tolerance in Wheat Production

Wheat is one of the world’s principal staple crops, yet its productivity is increasingly threatened by rising temperatures and more frequent heat waves. High temperature episodes during key reproductive stages such as anthesis and grain filling can reduce photosynthetic capacity, impair membrane integrity and disrupt carbohydrate metabolism, leading to substantial yield losses. Plants deploy a suite of adaptive responses, including maintenance of thylakoid membrane stability, accumulation of osmolytes, induction of heat shock proteins and activation of antioxidant systems that scavenge reactive oxygen species. At the genetic level, quantitative trait loci governing traits such as canopy cooling, early maturity and root architecture have been identified, offering targets for marker-assisted breeding. Advances in transcriptome profiling and genome-wide association studies are uncovering networks of stress-responsive genes, whilst physiological experiments are clarifying the timing and severity of heat exposure that wheat can endure. Integrating knowledge from physiology, biochemistry and genetics is central to developing new cultivars capable of sustaining yield under a warming climate.

Research from Nature Portfolio

Recent studies have characterised the combined effects of pre-anthesis drought and heat on diverse wheat genotypes, revealing that simultaneous heat and water deficit at the reproductive stage can reduce grain yield by nearly half. Analysis of over one hundred elite lines demonstrated that key physiological traits—chlorophyll content before and after flowering, water-soluble carbohydrate reserve, proline accumulation and early anthesis—strongly correlate with yield under stress. Disintegration of chloroplast membranes and reduction in sink strength were more pronounced under heat, whereas water status was more affected by drought. Principal component analysis highlighted combinations of traits that underpin resilience, guiding the selection of germplasm for breeding programmes aimed at dual tolerance to heat and drought.

Heat Stress Tolerance in Wheat Production publication trend

The graph below shows the total number of articles in heat stress tolerance in wheat production across all publications each year (not limited to Nature Index journals).

Technical terms

Reactive oxygen species (ROS): Highly reactive molecules formed under stress that can damage cellular components.

Thylakoid membrane: A membrane system within chloroplasts where the light reactions of photosynthesis occur.

Osmolyte: Small organic compounds that maintain cell turgor and protect macromolecules under stress.

Heat shock protein (HSP): A class of chaperones induced by high temperature that stabilise proteins and membranes.

Quantitative trait locus (QTL): A genomic region associated with variation in a quantitative trait such as canopy temperature depression.

Anthesis: The flowering phase when wheat florets open and are most susceptible to stress.

References

1. Effects of Pre-Anthesis Drought, Heat and Their Combination on the Growth, Yield and Physiology of diverse Wheat (Triticum aestivum L.) Genotypes Varying in Sensitivity to Heat and drought stress. Scientific Reports (2019).
2. Effects of high temperature stress during anthesis and grain filling periods on photosynthesis, lipids and grain yield in wheat. BMC Plant Biology (2020).
3. Terminal drought and heat stress alter physiological and biochemical attributes in flag leaf of bread wheat. PLOS ONE (2020).
4. Heat stress responses in a large set of winter wheat cultivars (Triticum aestivum L.) depend on the timing and duration of stress. PLOS ONE (2019).
5. Heat stress-responsive transcriptome analysis in heat susceptible and tolerant wheat (Triticum aestivum L.) by using Wheat Genome Array. BMC Genomics (2008).
6. Common genetic basis for canopy temperature depression under heat and drought stress associated with optimized root distribution in bread wheat. Theoretical and Applied Genetics (2015).
7. Mapping QTL for the traits associated with heat tolerance in wheat (Triticum aestivumL.). BMC Genomic Data (2014).