Effects of Salt Stress on Photosynthetic Fluorescence Characteristics, Antioxidant System, and Osmoregulation of Coreopsis tinctoria Nutt.

Coreopsis tinctoria Nutt. ( C. ) is used in composite tea material and has important medicinal functions. Soil salinization affects the growth development of Xinjiang (China). Here, we discussed changes photosynthesis physiological characteristics seedlings treated with different concentrations NaCl [0 (CK), 50, 100, 150, 200, 250 mmol·L −1 ] for 12, 24, 72 hours. The results showed that net photosynthetic rate (P n ), stomatal conductance g S transpiration (T r inhibition (L s decreased significantly increasing NaCl. Salt stress promoted accumulation peroxidase (POD), catalase (CAT), soluble sugar, protein, free proline (Pro). A highly significant positive correlation was found between L F v /F m ; o sugar CAT; protein. most sensitive to 150 NaCl, its salt tolerance increased by reducing fluorescence parameters, improving antioxidant enzyme system, regulating osmotic substances.