<p>(A) Seeds of <i>A</i>. <i>sparsifolia</i> (Scale bar = 2.0 cm). (B) Typical phenotype of the <i>A</i>. <i>sparsifolia</i> seedlings at 7 days post treatment with PEG-6000 (Scale bar = 1.0 cm). The <i>A</i>. <i>sparsifolia</i> seeds were first treated with concentrated sulfuric acid (98%) for 20 min, and then put on fully wetted filter paper at 25°C in the dark for 24 h. The germinated seeds were selected and transferred to petri dishes containing filter paper saturated with the different percentages of PEG-6000 solution (0, 90, 150, 220, 270 and 320 g/L), and were remained at 25°C in the dark for 3 days followed by 4 additional days but under 16-h light/8-h dark. At least 15 seedlings were included in each different treatment, and three independent experiments were preformed. (C) Average length of the primary roots of <i>A</i>. <i>sparsifolia</i> treated with PEG-6000 at 7 days. Error bars represent SE. P values determined by Student t test (** p < 0.01).</p