A population of 114 recombinant inbred lines (RILs), derived from the cross Opata85 · W7984, was used to genetically analyze the response of wheat to salt stress. This analysis resulted in the identification of 47 QTL mapping to all wheat chromosomes except 1B, 1D, 4B, 5D and 7D. Of these QTL, 10 were effective during the germination stage, and 37 at the seedling stage. Many of the traits related to salt tolerance mapped to common chromosome intervals, such as Xglk683-Xcdo460 on chromosome 3A, Xfbb168-Xbcd147 on chromosome 3B, Xcdo1081-Xfbb226 on chromosome 4DL and Xpsr106-Xfbb283 on chromosome 6DL. QTL located in the interval Xcdo1081-Xfbb226 (chromosome 4DL) were effective during the germination stage, whereas those in the interval Xfbb231.1-Xmwg916 (chromosome 6DL) were relevant to the seedling stage. The QTL in the intervals Xglk683-Xcdo460 (chromosome 3AS) and Xfbb168-Xbcd147 (chromosome 3BL) were effective at both the germination and seedling stages.

The identification of genome-wide selection signatures can provide insights on the mechanisms of natural and/or artificial selection and uncover genes related to biological functions and/or phenotypes. Tibetan sheep are an important livestock in Tibet, providing meat and wool for Tibetans who are renown for breeding livestock that adapt well to high altitudes. Using whole-genome sequences with an effective sequencing depth of 5×, we investigated the genomic diversity and structure and, identified selection signatures of White Tibetan, Oula and Poll Dorset sheep. We obtained 30,163,679 Single Nucleotide Polymorphisms (SNPs) and 5,388,372 indels benchmarked against the ovine Oar_v4.0 genome assembly. Next, using FST, ZHp and XP-EHH approaches, we identified selection signatures spanning a set of candidate genes, including HIF1A, CAPN3, PRKAA1, RXFP2, TRHR and HOXA10 that are associated with pathways and GO categories putatively related to hypoxia responses, meat traits and disease resistance. Candidate genes and GO terms associated with coat color were also identified. Finally, quantification of blood physiological parameters, revealed higher levels of mean corpuscular hemoglobin measurement and mean corpuscular hemoglobin concentration in Tibetan sheep compared with Poll Dorset, suggesting a greater oxygen-carrying capacity in the Tibetan sheep and thus better adaptation to high-altitude hypoxia. In conclusion, this study provides a greater understanding of genome diversity and variations associated with adaptive and production traits in sheep.