COMPARISON OF SHOOT DRY-WEIGHT, NA-C-13 VALUES OF ARI-E AND OTHER SEMIDWARF BARLEY MUTANTS UNDER SALT-STRESS( CONTENT AND DELTA)

Four breviaristatum (short awned and semi-dwarf) barley mutants; ari-e .1, ari-e.119, ari-e.156 and ari-e.228 were compared with other semi-d warf mutants; Golden Promise, Alf, Pallas and Diamant along with their non-mutant parents; Bonus, Foma, Maythorpe, Bomi and Valticky, for re sponse to salt stress. Plants were exposed to hydroponic salt treatmen ts (NaCl at 25 and 175 mol m(-3)) for 4 weeks, after which response wa s measured in terms of shoot dry weight, sodium content and delta(13)C . I, general ari-e mutants and Golden Promise had significantly lower Na+ contents than the other mutants. They also had significantly more negative delta(13)C values than the other lines in stressed (175 mol m (-3) NaCl) conditions. There was a positive correlation (r = 0.71, p < 0.01) between shoot Na+ and delta(13)C values so that delta(13)C beca me less negative with increasing Nai content. Shoot dry weights were c ompared to shoot Na+ and delta(13)C values. The ari-e and Golden Promi se mutants showed less reduction in dry matter production in salt stre ss relative to the control treatment than all the other lines. The dat a suggest that ari-e mutants and Golden Promise are better adapted to salt stressed environments than the other lines examined. Tests for gi bberellic acid sensitivity revealed that ari-e mutants and Golden Prom ise responded weakly to GA(3), while other dwarf mutants Pallas, Diama nt and Alf along with their parents Bonus, Foma, Maythorpe, Valticky a nd Bomi were highly sensitive. Our results support previous findings t hat ari-e mutants and the GPert mutant are allelic.