Selection of heat and drought stress tolerance in a diverse bread wheat panel.

Citation

Sangha, J. S. Randhawa, H. Cuthbert, R. D. Dhaliwal, R. Wang W. (2023). Selection of heat and drought stress tolerance in a diverse bread wheat panel. The Canadian Tri-Society meeting CPS-CSA-CSHS), June 17 to 21 2023, Ottawa, ON.

Plain language summary

Development of new heat and drought resilient cultivars is required to address the impact of heat and drought stress on wheat production. This is important to meet the increasing demand of food for the growing world’s population. This study aims to determine heat and drought stress response in a global collection of 403 diverse bread wheat lines. Data shows grain yield in two locations (Lethbridge and Swift Current) varied from 206 to 899 g/plot. Significant but moderate correlations were observed between grain yield and different vegetation indices collected with a field spectrometer, indicating the potential to develop high grain yield germplasm for hot and dry environments. A smaller number of candidate wheat lines were shortlisted for further characterization for heat and drought stress response in multilocation field trials.

Abstract

Extreme weather events, such as heat and drought, could negatively impact the crop growth and production. Development of new drought resilient cultivars may help to address the impact of heat and drought on wheat production, and help to and meet the increasing demand of food for the growing world’s population. A field based study was completed in 2022 under two environments (Swift Current, SK and Lethbridge AB) to determine heat and drought stress response in a global collection of 403 diverse bread wheat lines. Mean grain yield for both locations showed significant genotypic variation (p<0.0001) ranging from 206 to 899 g/plot, but no differences were observed between environments. Among various spectral indices collected at the grain-fill stage, significant but moderate correlations were observed between grain yield and red normalized difference vegetation index (RNDVI=0.51), green normalized difference vegetation index (GNDVI=0.51), and vegetation index (VI=0.51) and). Negative but low correlations were observed between grain yield and water index (WI=-0.21), and four other normalized water indices (NWI-1 to NWI-4). The number of seeds per spike also correlated positively with grain yield (r=0.32). These results helped to shortlist a smaller number of candidate wheat lines for further characterization of heat and drought stress response in multilocation field trials.