【摘要】 【目的】为探讨盐碱胁迫条件下沙枣幼苗的生长与光合特性,以掌握沙枣苗期不同胁迫条件下的抗逆性,为培育沙枣耐盐碱品种和改进栽培管理措施提供理论基础。【方法】选取1年生长势较一致的沙枣幼苗为试验材料,采用盆栽试验并进行随机区组设计。试验共分4个试验组和1个对照组,以200 mmol·L^-1、pH8.07～10.29的碱性复合盐为处理,对照用清水处理。6个试验周期后对其生长指标与光合特性进行了初步测定。【结果】相同Na+浓度的碱性复合盐胁迫条件下,沙枣幼苗的光合参数出现明显变化,其净光合速率（A）、蒸腾速率（E）、气孔导度（gsw）分别随胁迫处理pH值升高而下降,苗高生长量、地径生长量、新梢生长量下降明显;在Ph值达到8.67以后,随着NaHCO₃、Na₂CO₃比例增加,生长显著下降。相关分析表明3个生长指标与净光合速率（A）呈极显著正相关（P <0.01）,并且均与蒸腾速率、气孔导度呈显著正相关（P <0.05）。通过光和特性与生长指标的隶属函数综合分析表明,随着pH值的升高,碱性复合盐对沙枣苗期的胁迫程度增强。【结论】在相同Na⁺浓度碱性复合盐胁迫条件下,盐碱胁迫效应显著。在本试验范围内,200 mmol·L^-1的碱性复合盐不同处理条件下,随着处理组pH的增大,生长与光合指标呈下降趋势;当pH值升至8.67以后,各生长指标下降明显,从而说明了高pH碱性复合盐胁迫条件下,沙枣幼苗对盐的耐受程度强于碱,但碱性盐胁迫更强。更多还原

【Abstract】 【Objective】In order to study the growth and photosynthetic characteristics of Elaeagnus angustifolia seedlings under salt and alkali stress,and to master the stress resistance of Elaeagnus angustifolia seedlings under different stress conditions,so as to provide a theoretical basis for cultivating salt and alkali tolerant varieties and improving cultivation and management measures of Elaeagnus angustifolia.【Method】One year growth vigor of Elaeagnus angustifolia seedlings was selected as experimental materials. Pot experiment and random block design were used. The experiment was divided into 4 experimental groups and 1 control group,treated with 200 mmol·L^-1 alkaline complex salt with pH 8.07-10.29,and the control group was treated with water. The growth index and photosynthetic characteristics were measured after 6 cycles.【Result】The net photosynthetic rate（A）,transpiration rate（E）and stomatal conductance（GSW）of Elaeagnus angustifolia seedlings decreased with the increase of pH value,while the growth of seedling height,ground diameter and new shoot decreased significantly;After the pH value reached 8.67,the growth decreased significantly with the increase of NaHCO₃ and Na₂ CO₃. Correlation analysis showed that the three growth indexes were significantly positively correlated with net photosynthetic rate（A）（P < 0.01）,transpiration rate and stomatal conductance（P < 0.05）. Through the comprehensive analysis of the subordinate function of light and characteristics and growth index,the results showed that with the increase of pH value,the stress degree of alkaline complex salt on Elaeagnus angustifolia seedlings increased. 【Conclusion】Under the same concentration of Na⁺,the effect of salt alkali stress was significant. In the range of this experiment,under different treatment conditions of 200 mmol·L^-1 alkaline complex salt,with the increase of pH in treatment group,the growth and photosynthetic index showed a downward trend;When the pH value increased to 8.67,the growth indexes decreased significantly,which indicated that the salt tolerance of Elaeagnus angustifolia seedlings was stronger than that of the alkali,but alkaline salt stress is stronger.更多还原