沙棘对碱性盐胁迫的形态和生理响应

Morphological and physiological response of Hippophae rhamnoides on alkaline salt stress

采用50、100、150 mmol·L-1 3种浓度的Na2CO3、NaHCO3及二者混合盐对2年生沙棘幼苗进行胁迫处理,通过比较分析胁迫后沙棘幼苗的形态和细胞膜透性、脯氨酸含量、可溶性糖含量的变化,探讨沙棘对Na2CO3、NaHCO3和混合盐胁迫的适应能力。结果表明:在胁迫条件下,沙棘出现枯黄、落叶等盐害症状,随着胁迫浓度的加大和时间的延长,症状表现逐渐加重;电导率、脯氨酸含量、可溶性糖含量均随胁迫程度的加深呈上升趋势,胁迫前期变化相对稳定,后期变化幅度较大;形态表现和生理指标实验均反映出,不同类型盐碱胁迫对沙棘的伤害程度不同,单盐的迫害作用大于复盐,碱性盐的伤害作用大于酸性盐,即Na2CO3>NaHCO3>混合盐碱。此结果对提高沙棘在东北地区护坡工程中的应用提供了技术支持。

The two-year-oldHippophae rhamnoides seedlings were treated by stress method with three kinds of salts （Na2CO3, NaHCO3, the mixture of Na2CO3 and NaHCO3） under different concentrations （50,100,150 mmol/L）. The changes of morphology, cell membrane permeability, proline content and soluble sugar content ofH. rhamnoides seedlings after being stress treatment were compared and analyzed. Thus, the adaptive capacity ofH. rhamnoides seedlings under the stress of Na2CO3, NaHCO3 and the mixture of Na2CO3 and NaHCO3 was studied. The results show that under the condition of stress, the salt damage symptoms toH. rhamnoides seedlings appeared, such as leaf blight-yellow and leaf fell, with the increase of stress concentration and time, the symptoms gradually worsened; the electrical conductivity, proline content, soluble sugar content increased with the trend of stress degree going upward, in the stress earlier stage the change was relatively stable, later changed greatly; the morphology and physiological indicators reflected that the damage degrees of saline alkali stress toH. rhamnoides seedlings were different when the types of salt-alkali stress varied, the single salt’s effect was more than complex salt’s, the alkaline salt’s damage was stronger than others, that is to say Na2CO3〉NaHCO3〉[Na2CO3 and NaHCO3]. Theifndings provide a technical support in slope-protection project with H. rhamnoides seedlings in northeast of China.