Genes inducing Salt tolerance in wheat, Lophopyrum elongatum and amphiploid and their responses to ABA under salt stress

The Salt tolerance of facultatively halophytic Lophopyrum elongatum and closely related less salt-tolerant wheat Triticum aestivum L. is enhanced if plants are allowed to gradually acclimate to salt stress than if they are suddenly shocked. This acclimation to salt stress is regulated by Abscisic acid (ABA); a pretreatment with ABA substituted for the acclimation and increased tolerance of salt shock. The ABA-induced acclimation is rapid and coincides with enhanced expression of the "Early Salt Induced" genes (ESI) in the roots. Lophopyrum elongatum tolerates salt shock better than wheat and its genome confers greater tolerance of salt shock on wheat in their amphiploid. The tolerance of salt shock is principally controlled by chromosome 3E in the Lophopyrum elongatum genome. Wheat homoeologous chromosome 3A and 3D also control salt shock response. It is speculated that chromosome 3 in both species mediates salt shock response via ABA.