Genomic regions of durum wheat involved in water productivity

Abstract

Durum wheat is a staple food in 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 18 Mediterranean environments (in Morocco, Lebanon, and Jordan) representing a vast range of moisture levels. The accessions were assigned to water responsiveness classes, with genotypes ‘Responsive to Low Moisture’ reaching an average +1.5 kg ha–1 mm–1 yield advantage. Genome wide association studies revealed that six loci explained most of this variation. A second 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 three loci were tagged by kompetitive allele specific PCR (KASP) markers, and these were used to screen a third independent validation panel composed of elites tested across moisture stressed sites. The three KASP combined predicted up to 10% of the variation for grain yield at 60% accuracy. These loci are now ready for molecular pyramiding and transfer across cultivars to improve the moisture conversion of durum wheat.

Genomic regions involved in the control of 1,000-kernel weight in wild relative-derived populations of durum wheat

“…Briefly, it comprises 96 landraces from 24 countries and 288 cultivars and elite breeding lines from eight countries. A total of 10 subpopulations have been identified within it ( Kabbaj et al., 2017 ), and it has already been successfully used to identify the genomic loci involved in resistance to a damaging insect pest ( Bassi et al., 2019 ), phenology ( Gupta et al., 2020 ), and its responses to heat stress ( El Hassouni et al., 2019 ) and moisture stress ( Zaïm et al., 2023 ). This panel includes the parents of the NAM populations and their sister lines.…”

“…The genotypic and phenotypic data have been provided as Supplementary Tables S1 and S2 for panel 1 and 3, respectively. Phenotypic and genotypic data for panel 2 are freely available online as part of the article Zaïm et al., 2023 .…”

Trends and Perspectives for the Use of Crop Wild Relatives in Crop Breeding

“…Briefly, it comprises 96 landraces from 24 countries and 288 cultivars and elite breeding lines from eight countries. A total of 10 subpopulations have been identified within it (Kabbaj et al, 2017), and it has already been successfully used to identify the genomic loci involved in resistance to a damaging insect pest (Bassi et al, 2019), phenology , and its responses to heat stress (El Hassouni et al, 2019) and moisture stress (Zaïm et al, 2023). This panel includes the parents of the NAM populations and their sister lines.…”