Effects of Drought Stress on Water Content,Photosynthetic Characteristics and Antioxidant Enzymes of Artemisia desertorum leaves
Two-year-old Artemisia desertorum seedlings were used as materials to determine the water,photosynthetic characteristics and antioxidant enzyme activity characteristics of the leaves under different water conditions by potted plan water control experiment.The variation characteristics,response mecha-nism and quantitative relationship with soil moisture of each index during drought stress were analyzed,so as to reveal the response law of A.desertorum to drought stress.The results showed that 1)relative water content(RWC)of A.desertorum leaves continued to decrease with the increase of drought stress days,rel-ative water deficit(RWD)showed a fluctuating upward trend.2)The contents of total chlorophyll(Chl),Chla and Chlb all decreased with the increase of stress days,and decreased to the minimum at 30 days,while the content of carotenoid increased gradually with stress days.3)The main gas exchange parameters such as net photosynthetic rate(Pn),transpiration rate(Tr)and water use efficiency(WUE)showed ob-vious threshold response to soil moisture,and the threshold value of soil moisture was 6.48%-17.51%,which was suitable for normal photosynthetic physiological activities.4)Fv/Fm、Fv'/Fm'and qP decreased with stress days and light intensity,while NPQ increased slowly.5)The content of MDA increased with stress days,and the content of SOD increased with stress days,and the maximum was at 30 d.POD could respond to drought stress early,the CAT activity was inhibited by persistent drought stress,and the sensi-tivity of CAT to drought stress was poor.At the late stage of stress,under drought stress conditions,A.desertorum can adapt to arid environments by improving the light energy capture and conversion ability of leaves and enhancing the antioxidant capacity.
Artemisia desertorumdrought stressleaf water contentphotosynthetic characteristicsantioxi-dant enzyme activity
万方数据
维普
