The Effects of Saline Stress on the Growth of Two Shrub Species in the Qaidam Basin of Northwestern China

• Main Authors: Tan Zhang, Zhenzhong Zhang, Yuanhang Li, Kangning He
• Format: Article
• Language: English
• Published: MDPI AG 2019-02-01
• Series: Sustainability
• Subjects: salt tolerance; WUE; salt concentrations; photosynthetic parameters
• Online Access: https://www.mdpi.com/2071-1050/11/3/828

Soil salinization is a serious issue in the Qaidam Basin and significantly limits economic development. To explore the salt tolerance of two shrubs in this area, we determined several parameters, including the Soil and Plant Analyzer Development (SPAD), net photosynthetic rate (P_n), transpiration rate (T_r), intercellular carbon dioxide (C_i, &#956;mol mol^&#8722;1), stomatal conductance (G_s, umol m^&#8722;2s^&#8722;1), and water use efficiency (WUE) under different salt concentrations (0, 100, 200, 300, and 400 mmol&#183;L^&#8722;1). In addition, the shrubs of <i>Elaeagnus angustifolia</i> and <i>Lycium barbarum</i> of salt tolerance were evaluated. The photosynthetic parameters of <i>E. angustifolia</i> were more sensitive to salinity than those of <i>L. barbarum</i>, and SPAD, P_n, T_r, and WUE of <i>E. angustifolia</i> decreased significantly with increasing salt concentrations (<i>p</i> &lt; 0.05), while in <i>L. barbarum</i>, SPAD, P_n, and T_r decreased significantly with increasing salt concentrations (<i>p</i> &lt; 0.05), but the WUE of <i>L. barbarum</i> showed no significantly variation under the salt concentration gradient. The results of correlation matrix of photosynthetic index also indicated that the minimum salt tolerance of <i>E. angustifolia</i> and <i>L. barbarum</i> were 108.4 and 246.3 mmol&#183;L^&#8722;1, respectively. Our results provide a scientific basis for the selection of salt-tolerant plant species in of northwest China.