Increased tolerance to organic xenobiotics following recent allopolyploidy in Spartina (Poaceae).

•First PAH tolerance comparative analyses in Spartina.•Increased tolerance in the allopolyploid S. anglica compared to its parents.•Expression analysis of candidate GST genes (Tau family) in Spartina.•Allopolyploidization reprogrammed GST genes expression patterns under phenanthrene-induced stress.•The neo-allopolyploid S. anglica is a suitable candidate for phytoremediation.