Genomics-Assisted Breeding for combined heat and drought stress tolerance in Wheat

Swiss partners

• Agroscope: Dario Fossati (main applicant)

Partners in the MENA region

• Université Mohamed V - Rabat, Morocco: Fatima Henkrar (main applicant)

Presentation of the project

Morocco faces challenges in wheat production, with factors like drought and heat impacting yields. As a major wheatimporting country, it aims to reach self-sufficiency through a project focusing on combined heat and drought resistance. Genomic selection, an advanced breeding technology, offers a pathway to create wheat varieties with improved resistance to multiple stresses. The project aims to achieve combined heat and drought resistance in wheat through a comprehensive strategy. A carefully chosen panel of wheat accessions, comprising fixed lines and segregating populations, will be cultivated in two drought-prone sites in Morocco and, for Switzerland, in a relative warm-summer and dry location (compared to the rest of Switzerland). Detailed assessment of morphophysiological traits will provide insights into the performance of wheat varieties under heat and drought stress. During the genotyping phase, markers associated with heat and drought traits will be identified, facilitating the transfer of genes through marker-assisted methods to develop climate-resilient cultivars. The project also includes exploring allelic diversity within the wheat germplasm to enhance stress resilience. 

To accomplish these goals, the project plans to assemble and evaluate a Heat and Drought Tolerant Panel (HDTP) comprising a mix of Moroccan and Swiss wheat germplasm for a total of 250 wheat germplasms. Six field trials will be conducted under various conditions, including normally irrigated, terminal drought stress, late-planting simulating heat stress, and combined terminal drought and heat stresses. Advanced genotyping and genomic prediction methodologies will be employed to unravel the genetic composition of the HDTP. SNP markers obtained from genotyping will be used to identify marker-trait associations, and SSR markers associated with Meta-Quantitative Trait Loci related to combined heat and drought will contribute to allelic diversity analysis. Upon the project's conclusion, wheat varieties/lines demonstrating combined heatdrought stress resistance will be identified, the genetic basis of heat-drought stress resistance in Moroccan and Swiss adapted wheat varieties and developed lines will be elucidated and a genomic selection model for heat-drought resistance will be available for breeding.