Genetics of Na+ exclusion and salinity tolerance in Afghani durum wheat landraces

Genetics of Na+ exclusion and salinity tolerance in Afghani durum wheat landraces

Nawar Jalal Shamaya, Yuri Shavrukov, Peter Langridge, Stuart John Roy and Mark Tester. Genetics of Na+ exclusion and salinity tolerance in Afghani durum wheat landraces. BMC Plant Biology. https://doi.org/10.1186/s12870-017-1164-6
Nawar Jalal Shamaya, Yuri Shavrukov, Peter Langridge, Stuart John Roy And Mark Tester
Salinity tolerance, Leaf Na+ concentration, K+/Na+ ratio, Bulk Segregant analysis, SNP markers, HKT1;5
2017
‚ÄčBackground
Selecting for low concentration of Na+ in the shoot provides one approach for tackling salinity stress that adversely affects crop production. Novel alleles for Na+ exclusion can be identified and then introduced into elite crop cultivars.

Results
We have identified loci associated with lower Na+ concentration in leaves of durum wheat landraces originating from Afghanistan. Seedlings of two F2 populations derived from crossings between Australian durum wheat (Jandaroi) and two Afghani landraces (AUS-14740 and AUS-14752) were grown hydroponically and evaluated for Na+ and K+ concentration in the third leaf. High heritability was found for both third leaf Na+ concentration and the K+/Na+ ratio in both populations. Further work focussed on line AUS-14740. Bulk segr‚Äčegant analysis using 9 K SNP markers identified two loci significantly associated with third leaf Na+ concentration. Marker regression analysis showed a strong association between all traits studied and a favourable allele originating from AUS-14740 located on the long arm of chromosome 4B.

Conclusions
The candidate gene in the relevant region of chromosome 4B is likely to be the high affinity K+ transporter B1 (HKT1;5-B1). A second locus associated with third leaf Na+ concentration was located on chromosome 3BL, with the favourable allele originating from Jandaroi; however, no candidate gene can be identified.
1471-2229