Genome sequence of Arabidopsis thaliana Bu-5 wild type and the mutant

Plants often encounter osmotic stress caused by drought, cold, or salinity and have evolved acquired tolerance systems against more severe stresses. We previously found that acquired osmotolerance induced after salt stress is widespread among Arabidopsis thaliana accessions and identified ACQOS as the responsible gene, causing detrimental autoimmunity via ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1) and PHYTOALEXIN DEFICIENT4 (PAD4) under osmotic stress, thereby reducing osmotolerance. However, it remains unclear how the tolerance is established. To reveal the mechanism underlying the acquired osmotolerance, we here isolated an acquired osmotolerance-defective (aod) 13 mutant by screening 30,000 M2 seedlings obtained from ion beam-mutagenized seeds of Bu-5, an accession with acquired osmotolerance.