Phenotype characteristics of OPN and LPN taproots. a The typical phenotypes of OPN (left) and LPN taproot (right), scale bar: 10 cm. b The statistical result of length–width ratios of OPN and LPN taproots. LX, SL, and SP represent Luxi county, Shilin county, and Shipin county, respectively. Data are presented as mean ± s.d. (n = 5). The asterisk and double asterisks represent significant difference determined by the independent-sample t-test in PASW at p < 0.05 (*) and p < 0.01 (**), respectively.