Effects of Drough Stress on Physiological Populus euphratica and Elaeagnus angustifolia Seedlings
Screening of stress-resistant tree species and optimization of shelterbelt tree species configuration is an effective ap-proach to solve the issue of extensive tip withering and decline in farmland shelterbelts in extremely arid areas.Using native tree species seedlings,Populus euphratica and Elaeagnus angustifolia,in the Tarim Desert as experimental materials,the study employed potted water control method to investigate the dynamic responses of antioxidant enzyme activity,osmotic regulatory substances to drought stress severity,stress duration,and differences in drought resistance of the two tree spe-cies seedlings.The results showed that:(1)With the aggravation of drought stress severity and prolongation of stress dura-tion,the mass fraction of leaf free proline(Pro),soluble protein(SP),malondialdehyde(MDA)molar concentration,leaf saturation deficit of P.euphratica and E.angustifolia,and superoxide dismutase(SOD)activity of P.euphratica ex-hibited an increasing trend.The leaf peroxidase(POD)activity and leaf relative water content of the two tree seedlings showed a decreasing trend.(2)With the aggravation of drought stress severity,the leaf Pro and SP mass fractions of E.angustifolia were significantly higher than those of P.euphratica,and the SOD activity of P.euphratica was higher than that of E.angustifolia,with the POD activity showing the opposite trend.Both P.euphratica and E.angustifolia seedlings maintained leaf cell osmotic pressure with Pro and SP,and synergistically adapted to drought stress by clearing reactive ox-ygen species(ROS)through SOD.(3)Comprehensive analysis indicated that the drought resistance of E.angustifolia seedlings was superior to that of P.euphratica seedlings.It is suggested to prioritize the selection of E.angustifolia in the construction of oasis farmland shelterbelts in arid areas,establish mixed forests with E.angustifolia and P.euphratica as the main tree species,and replant E.angustifolia during the transformation and restoration of degraded shelterbelts to re-store the ecological functions of farmland shelterbelts.
Drought resistanceOsmoregulation substancesProtective enzymesNative tree species
万方数据
维普
