Germination rates of wild-type, atairp2, and 35S:AtAIRP2-sGFP plants in response to ABA and NaCl. A, ABA sensitivity of the wild type (WT), two atairp2 mutant alleles (atairp2-1 and atairp2-2), and AtAIRP2 overexpressors (transgenic lines 10 and 19) during the germination stage. Sterilized seeds were imbibed in water for 2 d at 4°C and incubated on MS medium in the presence of different concentrations of ABA (0, 0.2, 0.4, and 0.8 μm) at 22°C under a 16-h-light/8-h-dark photoperiod. Germination percentages were determined in terms of radical emergence 3 d after germination and cotyledon greening 7 d after germination. sd values were determined from four biological replicates (n > 36). Bars = 0.5 cm. B, NaCl sensitivity of the wild type, two atairp2 mutant alleles (atairp2-1 and atairp2-2), and AtAIRP2 overexpressors (transgenic lines 10 and 19) during the germination stage. Germination rates were determined in the presence of different concentrations of NaCl (0, 75, 100, and 125 mm) as described above. Data represent means ± sd (n > 36) from three independent experiments. [See online article for color version of this figure.]