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Crop wild relatives (CWRs) are an important source of genetic diversity for crop improvement. The aim of this study was to assess the usefulness of deploying CWRs in durum wheat [Triticum turgidum L. subsp. durum (Desf.) van Slageren] breeding. A set of 60 accessions was selected to include cultivars from nine countries, top lines obtained via elite-by-elite crossing, and CWR-derived lines. These accessions were screened for resistance against four major fungal diseases to reveal that CWR-derived lines are a good source of resistance against Septoria leaf blotch (Zymoseptoria tritici), while they were highly susceptible to tan spot (Pyrenophora tritici-repentis). Drought tolerance was assessed at eight environments with contrasting nitrogen levels and tillage practices to reveal a clear superiority of CWR-derived lines for grain size as well as higher grain yield (GY) under low nitrogen and normal tillage (NT). Temperature-stress tolerance was assessed at four heat-stressed environments along the Senegal River to confirm CWR-derived had up to 42% yield advantage and a higher grain number per spike (GNspk). Combined testing under plastic heat tunnels imposed at the time of flowering also revealed good performance of CWR-derived lines. However, the CWR-derived lines had low gluten sedimentation index and poor yellow color compared with cultivars and elite germplasm. High genetic diversity was found in CWR-derived lines with 75% of individuals having minor allele frequency (MAF) of 40-44% for frequent alleles but low genetic diversity for alleles with low frequency. In addition, 8-13% of the CWR parent genome

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Durum wheat is a staple food of the Mediterranean Basin, mostly cultivated under rainfed conditions. As such, the crop is often exposed to moisture stress. Therefore, the identification of genetic factors controlling the capacity of genotypes to convert moisture into grain yield (i.e. water productivity) is quintessential to stabilize production despite climatic variations. A global panel of 384 accessions was tested across eighteen Mediterranean environments (Morocco, Lebanon, and Jordan) representing a vast range of moisture levels. These accessions were assigned to water responsiveness classes, with genotypes 'Responsive to Low Moisture' reaching an average + 1.5 kg ha-1 mm-1 advantage. Genome wide association studies (GWAS) revealed that six loci explained the majority of this variation. A second germplasm validation panel tested under moisture stress confirmed that carrying the positive allele at three loci on chromosomes 1B, 2A and 7B generated an average water productivity gain of + 2.2 kg ha-1 mm-1. These loci were tagged by Kompetitive Allele Specific PCR (KASP) markers. Screening by KASP of a third independent germplasm validation panel tested across moisture stressed sites confirmed that these loci explained 34% of the variation for grain yield at 65% accuracy. These are the first ever reported markers truly ready for deployment by molecular breeding to convert moisture into yield in durum wheat.