Carvone (a) and limonene (b) content in spearmint cultivated
in soil and in a deep flow technique (DFT) hydroponic system using
different nutrient formula [i.e. plant standard nutrient (SM1), plant
standard nutrient plus amino acid mixture (SM2), plant standard
nutrient plus sulphur compound (SM3) and plant standard nutrient
plus a combination of amino acid mixture and sulphur compound
(SM4)]. Values represent mean ± SE. Different letters within each
species of mint indicate significant differences at P = 0.05