Selection for Salt‐Resistant Spring Wheat 1

Salt buildup in agricultural soils threatens irrigation agriculture in arid and semiarid regions of the world. Development of salt resistant crops may allow increased production in areas plagued by salt. Although ample sources of genetic diversity exist for most of the major crops, adequate screening methods for isolating salt‐resistant lines have yet to be developed. Wheat was chosen as a test case to investigate the current availability of salt‐resistant germplasm in the world collection. Over 5000 accessions of hexaploid wheat were screened in solution culture salinized with sea salt. Screening at 85% seawater yielded 312 individual selections capable of vigorous growth at germination and emergence. These were recovered and transferred to nonsaline conditions for seed multiplication. Subsequent screening of the next generation was done over the entire life cycle at 50% seawater, resulting in the isolation of 29 salt‐resistant lines. Salt‐sensitive lines were visually evaluated for uniformity of leaf damage at 25% seawater. Three resistant and two sensitive selections were compared with ‘Anza’ and ‘Kharchia’ for biomass production in solution cultures salinized to 20, 40, and 60% seawater. At the highest salinity, average biomass production was 6.4% of the controls for the resistant selections, 5.9% for ‘Kharchia’, 3.7% for ‘Anza’, and 1.6% for the sensitive selections. These results indicate that screening wheat at high salinities over a single generation can be effective in identifying salt‐resistant genotypes.