Figure 1.

Effects of different nitrate levels on the growth of Arabidopsis Columbia ecotype (AT-Col) and Thellungiella Shandong (Th-S) and Yukon (Th-Y) ecotypes (A; bars = 1 cm), shoot fresh weight (B), and anthocyanin content (C). The plants were continuously grown at three different N levels, 4 mm nitrate (sufficient N), 1 mm nitrate (mild limited N), and 0.4 mm nitrate (severe limited N), for 20 and 23 d for Arabidopsis and Thellungiella, respectively. Data are means ± sd (n = 3), and each replicate consisted of a pool of 10 to 15 plants. Bars with different letters indicate a significant difference at P < 0.05 (Fisher's protected lsd test). White bars, Arabidopsis; light gray bars, Thellungiella Shandong ecotype; dark gray bars, Thellungiella Yukon ecotype. FW, Fresh weight.