中国柽柳幼苗叶片生理特性对碱胁迫的响应

Response of Leaves Physiological Characteristics of Tamarix chinensis Seedlings to Alkali Stress

以中国柽柳为试材,通过盆栽试验,研究混合碱(NaHCO_3和Na_2CO_3摩尔比为9:1)不同浓度胁迫下(100、200、300、400 mmol/L)中国柽柳幼苗叶片生理特性和株高的影响。结果表明:与对照相比,中国柽柳叶片的相对含水量在碱浓度为100、200、300、400 mmol/L时均显著降低,分别下降8.82%、34.49%、43.27%、45.43%;而叶片丙二醛、可溶性糖和脯氨酸含量则随着碱浓度的升高呈递增的趋势,其中100、200、300、400 mmol/L碱处理的脯氨酸含量分别较对照显著高出36.37%、56.41%、77.35%、84.25%。此外,不同碱浓度处理的株高大小次序为对照>100 mmol/L>200 mmol/L>300 mmol/L≈400 mmol/L,其中100、200、300、400 mmol/L处理的株高分别比对照显著降低45.95%、62.16%、70.27%、74.05%,表明不同程度的碱胁迫均显著抑制了中国柽柳的生长。综合分析认为,以NaHCO_3和Na_2CO_3为主要盐分的碱胁迫对中国柽柳的生长发育具有一定的抑制作用,随着碱胁迫程度的加剧,抑制作用越来越大。

A pot experiment was conducted to determine the effects of mixed alkali（the mole ratio of NaHCO3 and Na2CO3 was 9：1） at different concentrations of 100, 200, 300, and 400 mmol/L on physiological characteristics of leaves and plant height of T. chinensis seedlings. The results showed that in comparison with the control, the relative water contents in leaves of T. chinensis significantly decreased by 8.82%, 34.49%,43.27%, and 45.43%, respectively, at the alkali concentration of 100, 200, 300, 400 mmol/L; whereas the contents of MDA, soluble sugar and proline presented an increasing trend along with the increase of alkali concentrations. Compared with the control, the proline contents increased by 36.37%, 56.41%, 77.35%, and 84.25%, respectively, at the alkali concentration of 100, 200, 300, and 400 mmol/L. In addition, the order ofplant height at different alkali concentrations was as follows： control 100 mmol/L 200 mmol/L 300 mmol/L≈400 mmol/L, and the plant height decreased by 45.95%, 62.16%, 70.27%, 74.05%, respectively, at the alkaliconcentration of 100, 200, 300, 400 mmol/L, significantly in contrast to the control. The study suggested thatdifferent degrees of alkali stress equally inhibited the growth of T. chinensis seedlings. As a result, the alkalistress mainly including NaHCO3 and Na2CO3 has significantly inhibitory effect on the growth of T. chinensis,and the inhibitory effect becomes greater with the increase of alkali stress.