
TY  - JOUR
A1  - Munns, Rana 
A1  - Rebetzke, Gregory J. 
A1  - Husain, Shazia 
A1  - James, Richard A. 
A1  - Hare, Ray A. 
T1  - Genetic control of sodium exclusion in durum wheat
JF  - Australian Journal of Agricultural Research
JO  - Aust. J.  Agric. Res.
Y1  - 2003
VL  - 54
IS  - 7
SP  - 627
EP  - 635
KW  - 
UR  - https://doi.org/10.1071/AR03027 
N2  - Salt tolerance in the genus Triticum is associated with low accumulation of Na+ in leaves. Durum and other tetraploid wheats generally have high accumulation of Na+ relative to bread wheat, and are salt sensitive, but a durum wheat landrace, Line 149, was found to have unusually low leaf Na+ accumulation. Populations were developed from crosses between 149 and the high Na+ accumulation variety Tamaroi, as well as between 149 and a durum wheat landrace with very high Na+ accumulation, Line 141. The third leaf of parental lines, F1, F2, and low- and high-selected F2:3 progeny was assayed for Na+ uptake when grown in 150 mM NaCl. Sodium concentrations were significantly (P &#60; 0.01) lower in the low Na+ uptake Line 149 compared with high Na+ uptake Tamaroi (5-fold greater Na+ accumulation) and Line 141 (7-fold greater Na+ accumulation). There was no evidence of any maternal genetic effect on Na+ accumulation. The F1 progeny mean was intermediate to the mid- and low-parent means, suggesting incomplete dominance gene action. Progeny in the F2 generation of both populations segregated for Na+ accumulation in a 15 (low Na+) : 1 (high Na+) ratio (&#967;215:1 = 0.27 and 0.46, P &#62; 0.50n.s. for 149/Tamaroi and 149/141, respectively), indicating duplicate dominance epistasis arising from segregation of 2 interacting dominant genes. Small yet significant (P &#60; 0.01) genotypic variation was also observed for minor genes affecting Na+ accumulation. Realised heritabilities were moderate to high (h2R = 0.43&#8211;0.90) across populations, indicating good response to selection for low Na+ accumulation in the F2 generation. The simple genetic control of Na+ accumulation suggests relative ease of selection of lines with low Na+ accumulation. However, presence of dominance will require selection to be delayed until after 1 or 2 generations of inbreeding, or after progeny-testing of selected low Na+ accumulation families. 
ER  -

