马蔺对不同浓度NaHCO_3胁迫的生理响应

Physiological Responses of Iris to NaHCO_3 Stress

为探讨不同浓度NaHCO3胁迫下,马蔺叶片的膜透性、可溶性蛋白及膜脂过氧化物含量的变化规律,以1年生马蔺实生苗为研究对象,通过对细胞膜透性、膜质过氧化产物MDA、SOD、POD和可溶性蛋白等指标进行测定,研究在盆栽控盐条件下,马蔺对NaHCO3胁迫的适应与响应。结果表明:随着NaHCO3浓度和胁迫时间的增加,对马蔺叶片可溶性蛋白含量的影响总体是先下降后上升的趋势,在30d时,0.4%和0.6%盐浓度胁迫下的马蔺的可溶性蛋白含量上升较大,分别比对照高:21.7%,38.6%;在NaHCO3盐胁迫的10～20d,马蔺叶片的的膜透性略有降低;在20～30d时,膜透性迅速上升;NaHCO3胁迫20d时,除对照外其他盐浓度胁迫下的马蔺叶片的POD活性都达到了最大值,分别比对照高95%,103%,496%;相同盐浓度胁迫下,随着时间的延长,SOD活性变化趋势是先下降后上升;MDA作为膜脂过氧化作用的主要产物之一,随着盐浓度的增加和盐胁迫时间的延长,在30d时0.6%浓度的马蔺叶片中MDA含量大量积累。综上所述,马蔺有抗盐(NaHCO3)胁迫的能力,是重要的盐碱地生植物,本研究为马蔺的抗盐碱性研究又提供了一有力证据,同时为今后将马蔺应用于治理盐碱土地增加了理论基础。

The Iris deal with NaHCO3 of different concentrations solution, In order to study Iris leaf membrane permeability, soluble protein and lipid peroxide content changes. In this experiment, 1-year-old Iris seedlings is the study object. According to the measurement of cell membrane permeability, MDA, SOD, POD, the soluble protein and other indicators, the response and adapt ability of Iris deal with NaHCO3. The result shows that： with more NaHCO3 concentration and increasing stress time stress, the content of Iris leaves soluble protein influenced by NaHCO3 salt stress tends to totally decline after the first prompt; on the 30th day, the content of Iris soluble protein with the stress of 0.4% and 0.6% concentration increases by 21.7% , 38.6% , respectively more than those of contrast; membrane permeability of Iris leaves slightly declines in the condition of NaHCO3 salt stress; during the 10th day and the 20th day, membrane permeability has a rapid increase, on the 20th day under NaHCO3 press, the POD activity has reached the maximum, by 32.1%, 13.8% and 29.5% respectively, compared to control; with the same salt stress and time extension of salt press, SOD activity first increases and then decreases; on the 30th day, as the product of membrane lipid peroxidation, the content of MDA in Iris leaves at 0.6% concentration accumulates dramatically, along with the increase in salt concentration and salt stress time. Based on the above analysis, there is salt（ NaHCO3 ） -stress resistance ability in Iris which is the important salinealkali plant. Therefore, the study provides powerful evidence of salt-stress resistance in Iris, which strengthen the theoretical basis that Iris should be applied to the saline-alkali field control.