Effects of net-wind and wind-sand flow on membrane permeability and membrane protection system of Lycium ruthenicum seedlings

To explore the adaptive capacity and response mechanism of Lycium ruthenicum under multiple net-wind and wind-sand flow stress, two-year-old potted seedlings of L. ruthenicum were used. Using the wind tunnel simulation test, the seedlings were stressed by net-wind and wind-sand flow at 8:00 am for 20 mins on the 1^st, 3^rd, and 5^th day at 9 m·s⁻¹ wind speed. Under stress, the morphological changes of the leaves were observed and recorded. The leaves were collected 30 mins after application of the stress on the 1^st, 3^rd, and 5^th days and during the same time on the 7^th day to determine and analyze the relevant indices of membrane permeability and membrane protection system. The results showed that some leaves of L. ruthenicum exhibited brown patches and wilting under the net-wind and wind-sand flow stress, and the damage caused by wind-sand flow was significantly higher than that by net-wind. Under net-wind stress, malondialdehyde (MDA) and soluble sugar (SS) increased initially and then decreased; peroxidase (POD) decreased initially and then increased, soluble protein (SP) fluctuation decreased; and membrane permeability, superoxide dismutase (SOD), and catalase (CAT) and proline (Pro) increased. Under wind-sand flow stress, SOD decreased initially and then increased; SS and SP decreased initially and then increased and then decreased; and as regards the variation trends of MDA, POD, membrane permeability, CAT and Pro levels were identical to those under net-wind stress. The results of this study are of great significance for revealing the adversity adaptation mechanism of L. ruthenicum to wind and wind-sand damage.