NaCl胁迫对蒙古岩黄芪幼苗抗氧化特性的影响

Effects of NaCl stress on the antioxidant properties of Hedysarum mongolicum

研究了不同浓度NaCl(0、5、25、50、100、200和300 mmol/L)对蒙古岩黄芪(Hedysarum mongolicum)幼苗生长特性、丙二醛含量、相对质膜透性及抗氧化酶活性的影响。结果表明:丙二醛和细胞膜相对透性随NaCl浓度的增加呈先降低后升高的趋势,5mmol/L NaCl处理下MDA含量最低,为1.68μmol/g;超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性随NaCl浓度的增加呈先升高后降低的趋势,在100mmol/L NaCl处理下达到最高,3种抗氧化酶活性依次为828.0,279.9和74.9U/(g·min);低浓度NaCl(≤100mmol/L)能提升幼苗株高、干重质量和抗氧化酶活性;高浓度NaCl则会抑制保护酶活性,对幼苗造成伤害。

A sand culture experiment was conducted to determine the effects of different concentrations of NaCl（0,5,25,50,100,200,300mmol/L）on the growth characteristics,MDA content,relative membrane permeability and the antioxidant enzyme activities in the leaves of Hedysarum mongolicum.The MDA content and relative membrane permeability had a trend of decreasing firstly and then increased with the increase of NaCl concentration.Under 5mmol/L NaCl treatment,the minimum MDA content was 1.68μmol/g,SOD,POD and CAT activity had a trend of increasing firstly and then decreasing with the increase of NaCl concentration,and the highest value appeared in the treatment with 100mmol/L NaCl,the activities of 3antioxidant enzyme were828.0,279.9and 74.9U/（g·min）.The results suggested that the low concentration of NaCl（≤100mmol/L）could improve the stem length,dry weight and the activity of antioxidant enzymes of Hedysarum mongolicum seedlings and the high concentration of NaCl could decrease the activity of protective enzyme and thus be harmful to the seedlings.