Locating QTLs Controlling Salt Tolerance in Barley Using Wheat-Barley Disomic Addition Lines

Asian Journal of Plant Sciences 02/2008; 7(2). DOI: 10.3923/ajps.2008.149.155
Source: DOAJ

ABSTRACT In order to investigate the chromosome(s) involved in salt tolerance based on criteria such as Na+, K+ and K+/Na+ discrimination, Stress Tolerance Index (STI) and Multiple Selection Index (MSI), an experiment was carried out under hydroponics culture using a wheat-barley chromosome addition lines. The results of this investigation based on the morphological, physiological and statistical analysis proved the hypothesis that most of the genes controlling traits affecting salt tolerance are located on chromosomes 4H and 5H. Though, chromosome 6H was also ranked among the genotypes with high STI and MSI, this may show that this chromosome carry QTLs affect on salt tolerance, as well. However, higher Na+ and lower K+/Na+ values of this line compared to 4H and 5H show the less effectiveness of this line on salt tolerance. Carrying higher positive traits on chromosome 4H compared to the 5H and 6H may indicate that the 4H chromosome has proportion of positive genes controlling salinity tolerance. The addition line carrying 4H chromosome of barley can be used in wide hybridization programs to transfer useful salt tolerance genes into wheat germplasm. This line may also be used in QTL mapping in the basic research programs.

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