Abstract

The global production of durum wheat (Triticum durum Desf.) is hindered by a constant rise in the frequency of severe heat stress events. To identify heat-tolerant germplasm, three different germplasm panels ("discovery," "investigation," and "validation") were studied under a range of heat-stressed conditions. Grain yield (GY) and its components were recorded at each site and a heat stress susceptibility index was calculated, confirming that each 1 degrees C temperature rise corresponds to a GY reduction in durum wheat of 4.6%-6.3%. A total of 2552 polymorphic single nucleotide polymorphisms (SNPs) defined the diversity of the first panel, while 5642 SNPs were polymorphic in the "investigation panel." The use of genome-wide association studies revealed that 36 quantitative trait loci were associated with the target traits in the discovery panel, of which five were confirmed in a "subset" tested imposing heat stress by plastic tunnels, and in the investigation panel. A study of allelic combinations confirmed that Q.icd.Heat.003-1A, Q.icd.Heat.007-1B, and Q.icd.Heat.016-3B are additive in nature and the positive alleles at all three loci resulted in a 16% higher GY under heat stress. The underlying SNPs were converted into kompetitive allele specific PCR markers and tested on the validation panel, confirming that each explained up to 9% of the phenotypic variation for GY under heat stress. These markers can now be used for breeding to improve resilience to climate change and increase productivity in heat-stressed areas.The use of a north-south gradient between the Senegal River and Morocco was introduced to assess heat tolerance.Critical loci, involved in the control of heat tolerance in durum wheat, was defined.Germplasm sources and loci tagged by kompetitive allele specific PCR to favor the introgression of heat tolerance alleles by breeding were presented.A new gold standard by using three germplasm panels to discover, investigate, and validate useful loci was studied.

Published in

The Plant Genome
2024, Volume: 17, number: 1, article number: e20414

SLU Authors

• Ortiz Rios, Rodomiro Octavio

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

• Dida, Mulatu Geleta

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

SDG13 Take urgent action to combat climate change and its impacts
SDG2 End hunger, achieve food security and improved nutrition and promote sustainable agriculture
SDG1 End poverty in all its forms everywhere


UKÄ Subject classification

Genetics and Breeding
Agricultural Science


Publication identifier

DOI: https://doi.org/10.1002/tpg2.20414

Permanent link to this page (URI)

https://res.slu.se/id/publ/128341