Safflower’s (Carthamus tinctorius L.) physio-biochemical mechanisms to improve its drought tolerance

Drought is a main stressor affecting plant production worldwide. Safflower (Carthamus tinctorius L.) known to exploit biochemical strategies tolerate drought stress. However, the little so far about these does not guarantee safflower yield stability in future. To fill gap, changes traits and antioxidant activities of were monitored using 100 genotypes under two non-stress drought-stress field conditions subsequent years (2017 2018). While stress was observed give rise reversible increases total phenolics (TPC), flavonoids (TFD), flavonols (TFL), anthocyanin (Ant), proline, malondialdehyde (MDA), activity, it decreased chlorophyll (ChlT) carotenoid (Car) contents safflower. Under stress, highest values for TPC (21.55 16.07 mg GAEg−1 fresh weight [FW]), Car (0.08 g−1 FW), 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity (98%) measured G16, averaged over study years. Also TFD (5.17 QEg−1 TFL (1.99 Ant (234.1 µmol ChlT (0.67 proline (851 μmol g −1 FW) recorded G80, G60, G23, G62, G33. The least MDA content (2.8 denoted G91 results both principal component correlation analyses demonstrated effective role tolerance. high genetic variance seen result heritability thereby improving tolerance cultivated prone regions. significant variations all indicated that traits, especially TFD, could be used as screening criteria genotypic selection arid climates.