Effect of different light intensities on the polyamine pattern (A: PUT: putrescine, B: SPD: spermidine, C: SPM: spermine, D: DAP: 1,3-diaminopropane) in the roots of plants grown under 16 h/8 h day/night light period with different light intensity conditions: 500 (elevated light: L1), 250 (medium light: L2) and 50 (low light: L3) µmol m2 s−1 LED light after 7 days of 0.3 mM exogenous putrescine (PUT), spermidine (SPD) or spermine (SPM) treatments or without any treatment (C). PUT: putrescine, SPD: spermidine, SPM: spermine, DAP: 1,3-diaminopropane. Data represent mean values ± SD. Different letters indicate significant differences at p ≤ 0.05 level, among all the values of the given compounds.