Abstract
Improving salinity tolerance in the most widely cultivated cereal, bread wheat (Triticum aestivum L.), is essential to increase grain yields on saline agricultural lands. A Portuguese landrace, Mocho de Espiga Branca accumulates up to 6 folds greater leaf and sheath sodium (Na+) than two Australian cultivars, Gladius and Scout, under salt stress. Despite high leaf and sheath Na+ concentrations, Mocho de Espiga Branca maintained similar salinity tolerance compared to Gladius and Scout. A naturally occurring single nucleotide substitution was identified in the gene encoding a major Na+ transporter TaHKT1;5-D in Mocho de Espiga Branca, which resulted in a L190P amino acid residue variation. This variant prevents Mocho de Espiga Branca from retrieving Na+ from the root xylem leading to a high shoot Na+ concentration. The identification of the tissue tolerant Mocho de Espiga Branca will accelerate the development of more elite salt tolerant bread wheat cultivars.
Footnotes
Funding This project was funded by the Grains Research and Development Corporation (GRDC): Project UA00145, UA00151, and the GRDC and the International Wheat Yield Partnership (IWYP): Projects IWYP39/ACP0009; IWYP60/ANU00027. The Australian Centre for Plant Functional Genomics (ACPFG) was jointly funded by the Australian Research Council (ARC) and the GRDC, SW was supported by the ARC DE160100804. The Plant Accelerator®, Australian Plant Phenomics Facility, is funded under the National Collaborative Research Infrastructure Strategy (NCRIS).