Fig. 1

The seeds (a), seedling (b), germinated (c), and fully grown (d) licorice plants in the hydroponics system containing a substrate mixture of cocopeat and perlite in a volumetric ratio of 1:1, with different ratios of ammonium to nitrate (1:0, 0.5:0.5 and 0:1) at 10 mM N in the nutrient solution.