Overexpression of <i>AtVIP1</i> inhibited seed germination and root length under ABA treatment.

<p>Identically stored seeds were surface sterilized and washed extensively with water and plated on MS0 medium plates containing 3% Suc in the absence or presence of 2.5 μM ABA. Plates were kept at 4°C in darkness for 3 d and then transferred to growth chambers (16 h light/8 h darkness regime) at 22°C. <b>(A)</b> Seed germination analysis of WT and <i>35S:AtVIP1</i> transgenic plants containing OE-VIP1–4, -5 and -7 under normal conditions (MS0) and ABA treatment (MS0 plus 2.5 μM ABA). <b>(B)</b> and <b>(C)</b> Seed germination rates of different <i>35S:AtVIP1</i> transgenic lines under normal conditions <b>(B)</b>, and 2.5 μM ABA treatment <b>(C)</b> at different time points. <i>35S:AtVIP1</i> transgenic lines displayed lower germination rates than WT. Values for each time point are means of three experiments, and each experiment comprised 60 plants. <b>(D)</b> Root growth WT and <i>35S:AtVIP1</i> transgenic plants under normal conditions (MS0) and 5 μM ABA treatment for 14 d. <b>(E)</b> Primary root lengths (cm) shown in <b>(D)</b> were measured 14 days after treatment. Values are means ± SD (n = 30) from three independent experiments. Asterisk indicates significant differences (Student’s t test,*P<0.05) between the Col-0 and <i>35S:AtVIP1</i> transgenic lines. <b>(F)</b> Relative expression analysis (fold change) of <i>AtVIP1</i> in WT and transgenic lines. Expression of <i>VIP1</i> in WT was normalized as 1. Results are means ± SD from three independent experiments, and asterisks indicate significant differences (Student’s t test,**P<0.01) between Col-0 and transgenic lines.