STRESS RESPONSE OF DIFFERENT PLANTS TO DOXYCYCLINE CONTAMINATION AND THEIR REMEDIATION POTENTIALS

To study the stress response of different plants under high-concentration doxycycline contamination and evaluate their remediation potentials for doxycycline contamination, 3 types of plants were selected for performing the germination and hydroponic experiments, including chicory, lettuce, and parsley. Based on it, the changes in seed germination, plant height, root length, and fresh weight were observed, and the contents of doxycycline in hydroponic nutrient solution over different periods of time were detected by high performance liquid chromatography. According to the results, it can be concluded that: 1) Doxycycline can promote the germination of chicory and lettuce seeds, but have an inhibitory effect on the germination of parsley seeds. The inhibitory effect of doxycycline on seed root length was significantly greater than shoot growth. 2) There were differences in the stress responses of three plants to doxycycline: the plant height, root length, and fresh weight of chicory and parsley had an obvious inhibitory effect on doxycycline; while doxycycline had no obvious inhibitory effect on the plant height and fresh weight of lettuce, it can promote the root growth of lettuce to a certain extent. 3) The removal rates for chicory, lettuce, and parsley to doxycycline in water were 81.75%, 58.42%, and 53.16% respectively. Chicory can be used as an alternative plant to degrade antibiotic contamination.