Efecto del estrés salino sobre la morfología y fitoquímica de orégano mexicano (Lippia graveolens Kunth) cultivado in vitro

Plants, being sessile organisms, suffer from a range of biotic and abiotic stress. In this investigation, oregano plants were grown in vitro under saline stress conditions (NaCl 25 mM), combined with different types of lights: white light (CTL), ultraviolet- C (UV-C) and broad-spectrum light (AE). Morphological changes were evaluated in the treated plants, as well as phytochemical parameters (total phenolic com­pounds, total flavonoids and antioxidant capacity). NaCl/CTL and AE conditions showed the highest numbers of activated buds. UV-C light showed the lowest number of buds and plant height, however, no effect from salinity was observed. Also, UV-C light caused the lowest amount of leaves and adventitious roots, which do not seem to be influenced by salinity. The stress condition that caused the highest amount of phenols was UV-C light, while the combination of NaCl/ UV-C showed the highest number of total flavonoids. As for the antioxidant capacity, NaCl/AE showed the highest capac­ity using both the DPPH and ABTS method. No correlation between phenols and antioxidant capacity was observed.