Figure 4

The spatial distribution of coumarins in the root sections of HBZ and QBZ (a: imperatorin and isoimperatorin; b: oxypeucedanin; c: phellopterin; d: byakangelicol; Scale bars: 2021/03/28: 2.23 mm; 2021/04/30, 2021/05/30: 2.27 mm; 2021/06/15, 2021/06/30: 2.45 mm; 2021/07/15: 3.73 mm; 2021/07/30: 4.52 mm).