NaCl处理对多枝柽柳(Tamarixramosissima)生长及生理的影响

以1年生多枝柽柳(Tamarix ramosissima)幼株为材料,采用盆栽试验研究不同浓度(0、50、100、200、400 mmol·L^-1)NaCl处理对多枝柽柳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)、过氧化氢酶(CAT)、过氧化物酶( POD)、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:低浓度(≤100 mmol·L^-1)的NaCl处理对多枝柽柳株高、冠幅面积、分枝数和叶、枝干重具有促进效应;高浓度(≥200 mmol·L^-1)的NaCl处理抑制了多枝柽柳生长,对侧根干重的抑制作用大于对冠幅面积、分枝数、叶干重、枝干重及株高的抑制.H₂O₂和MDA含量在低浓度(≤100 mmol·L^-1)NaCl处理下较对照未出现积累现象,随NaCl浓度升高(≥200 mmol·L^-1)二者含量较对照出现显著积累.低浓度(≤100 mmol·L^-1)NaCl处理下,多枝柽柳叶片SOD、POD、CAT和APX活性较对照均有所提高,高浓度的NaCl处理下SOD和POD活性开始降低.多枝柽柳叶片水势随NaCl处理浓度升高呈显著下降趋势.低浓度(≤100 mmol·L^-1)NaCl处理下脯氨酸和可溶性糖含量较对照呈上升趋势.

Effects of NaCl Treatments on Growth and Eco-physiological Characteristics of Tamarix ramosissima

A pot experiment was conducted to study the influence of different concentrations (0、50、100、200、400 mmol·L^-1) NaCl on the growth, leaf hydrogen peroxide (H₂O₂), malonaldehyde (MDA) content, superoxide dismutases (SOD), catalases (CAT), peroxidase (POD), ascorbate peroxidase (APX) enzymes activity, water potential, soluble sugar and proline contents of Tamarix ramosissima young plant. The results showed that shoot height, crown area, number of branches, dry mass of leaf and branch of T. ramosissima were promoted at lower NaCl concentrations (≤100 mmol·L^-1), however, the growth of T. ramosissima were inhibited at higher NaCl concentration (≥200 mmol·L^-1), and the suppression effect to lateral root dry mass was larger to crown area, number of branches, dry mass of leaf and branch, and was larger to shoot height. H₂O₂ and MDA contents were not accumulated at lower NaCl concentrations, but accumulated at higher NaCl concentrations (≥200 mmol·L^-1) compared with control level. SOD, POD, CAT and APX activities enhanced at lower NaCl concentrations (≤100 mmol·L^-1) compared with control level, whereas SOD and POD activities began to descend at higher NaCl treatments. Water potential in leaves of T. ramosissima reduced significantly with the increasing in NaCl concentrations. Proline and soluble sugar contents increased at lower NaCl concentrations compared with control level.