NaCl胁迫对大果白刺幼苗生长和抗逆生理特性的影响

Effects of salt stress on Nitraria roborowskii growth and physiological characteristics of stress resistance

采用盆栽试验,研究了不同浓度(0、50、100、200和400 mmol·L-1)NaCl处理对1年生大果白刺生长状况及叶片过氧化氢(H2O2)、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、过氧化物酶(POD)活性、抗坏血酸过氧化物酶(APX)活性、水势、可溶性糖和脯氨酸含量的影响.结果表明:与对照相比,低浓度NaCl处理(≤50 mmol·L-1)对大果白刺生长没有显著的抑制作用,叶片的SOD、POD、CAT和APX活性均有所提高;高浓度(>50 mmol·L-1)NaCl处理抑制了大果白刺的冠幅面积、分枝数和叶、枝、侧根干质量,叶片的SOD、CAT、POD活性和可溶性糖、脯氨酸含量显著下降.随NaCl处理浓度升高,H2O2和MDA含量增加,叶片水势降低.

A pot experiment was conducted to study the influences of different NaC1 concentrations （0, 50, 100, 200, 400 mmol . L^-1） on the growth, leaf hydrogen peroxide （H202） , malonalde- hyde （MDA） content, superoxide dismutases （SOD）, eatalases （CAT）, peroxidase （POD）, aseorbate peroxidase （APX） enzymes activity, water potential, soluble sugar and proline contents of Nitraria roborowskii. The results showed that the growth of N. roborowskii was not affected at low- er NaC1 concentrations （ ≤50 mmol . L^-1） , while the SOD, POD, CAT and APX activities in leaves of N. roborowskii were increased. However, higher NaC1 concentrations （ 〉50 mmol ~ L-i ） restrained the growth parameters of crown area, number of branches, dry mass of leaf, branch and lateral root, and remarkably reduced the SOD, POD and CAT activities, soluble sugar and proline contents in leaves of N. roborowskii. H2O2 and MDA contents in leaves were increased and water potential was reduced with increasing NaC1 concentrations.