Fig. 4

LeEIL-1expression levels (a) and shikonin production (b) of the randomly selected hairy root lines. WT, EV, Ei, and EO hairy root lines cultured in M9 production medium for 6 days. The values are means ± SD (n = 3), and the bars with different capital letters indicate significant differences at P < 0.01 (Least Significant Difference). The deep gray and moon logo indicate the hairy roots were cultured in the dark. Scatter diagram showing the significantly positive linear relationship between LeEIL-1 expression level and shikonin production (r = 0.8495; P < 0.001) (c)