关键词: 酸枣, 干旱胁迫, 生理生化

Abstract: One year seedlings of Ziziphus jujuba var. spinosa were used as test material, the pot water control method was used, and 4 treatments  including 80% (suitable water, CK), 60% (light stress, L), 40% (moderate drought, M), and 20% (severe drought, S) soil moisture content were set up to simulate different levels of drought stress. The relative water content, peroxidation product content, antioxidant enzymes activities and chlorophyll fluorescence parameters and other physiological characteristics of Z. jujuba var. spinosa seedlings under different drought stresses were investigated. The results showed that with the increase of drought stress level, the relative water content of leaves of Z. jujuba var. spinosa seedlings generally showed a decreasing trend; the malondialdehyde (MDA) content of Z. jujuba var. spinosa seedlings showed an increased trend; the free proline (Pro) content increased, as well as the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT). The photosynthetic fluorescence characteristics of Z. jujuba var. spinosa seedlings were influenced by drought stress significantly. Under the drought stress, the initial fluorescence (Fo) and non-photochemical quenching coefficient (qN) increased significantly, while the maximum fluorescence (Fm), photochemical quenching coefficient (qP), maximum photochemical efficiency PSII (Fv/Fm) and actual photochemical efficiency (ΦPSII) were significantly reduced. Drought stress had significant effects on the physiological indexes of Z. jujuba var. spinosa seedlings. The physiological indexes including activities of antioxidant enzymes and osmotic adjustment substances content of Z. jujuba var. spinosa seedlings were regulated in response to the drought stress.

Key words: Ziziphus jujuba var. spinosa, drought stress, physiological and biochemical characteristics