Investigation on the regeneration and morphology behaviors of Lilium tsingtauense under in vitro drought stress conditions

This study was conducted to investigate the regeneration and morphological behaviors of Lilium tsingtauense under drought stress under in vitro condition. Polyethylene glycol (PEG) used to crate drought stress conditions. For this purpose, in vitro bulblet scales were treated on MS medium supplemented with different concentrations of polyethylene glycol (0, 5, 10, 20, 40 g/l) for two months. The results of experiment showed that increasing the drought stress significantly affected (P 0.01) the dry/fresh weight ratio percentage of the explants. The highest percentage of dry/fresh weight ratio (18.19%) was obtained in the highest concentration of PEG (40 g/l) and compared to control (15.28%). No significant difference was observed in root length, but compared with the mean values revealed that the longer and shorter root length was observed in 5 g/l and 40 g/l, respectively. However, the results showed that the treatments had no effect on leaf number, bulblet number and leaf length. We conclude that one of the mechanisms of drought tolerance is the increase in dry weight and, to some extent, decrease root length.