Effects of Exogenous Calcium on Adaptive Growth, Photosynthesis, Ion Homeostasis and Phenolics of Gleditsia sinensis Lam. Plants under Salt Stress

Abstract

Salinity is the main environmental factor responsible for limited plant growth in many areas of the world. Gleditsia sinensis Lam. is a shelter forest tree species that does not require high-quality soil and can even grow in mild saline soil. This study mainly explored the tolerance of G. sinensis to salt and the effect of exogenous calcium addition on the growth of G. sinensis in a salinized soil. The concentrations of NaCl were set as 0 mmol/L, 100 mmol/L, and 200 mmol/L. Compared with the control, under the NaCl treatment of 200 mmol/L, it was observed that the leaves of G. sinensis turned yellow, the electrical conductivity significantly increased, and the water content and the chlorophyll content significantly decreased, which is probably unfavorable for growth. Our study showed that the addition of 10 mmol/L exogenous calcium chloride under salt stress had a positive effect on the growth and photosynthetic characteristics of G. sinensis. Moreover, the addition of exogenous calcium attenuated the cytotoxicity caused by Na+ under salt stress and promoted the equilibrium of ion homeostasis. More importantly, the addition of exogenous calcium ions was beneficial for the survival of G. sinensis plants on salinized land and the increase of effective active ingredient content including phenolic compounds, which is of direct significance for improving environmental problems such as desertification of saline-alkali land. In conclusion, we investigated the effect of salt treatment on G. sinensis, as well as the positive effects of exogenous calcium on the survival and growth of G. sinensis in salt environment, which provided a scientific basis for the targeted cultivation of G. sinensis in salinized land and the effective utilization of salinized and alkaline land.

Optimal exogenous calcium alleviates the damage of Snow-melting agent to Salix matsudana seedlings

“…Salt stress causes a reduction in plant stomatal conductance and chlorophyll content and reduced transpiration or reduced efficiency of photosystem II, resulting in difficulties in transporting ions from the soil to the root surface, which in turn affects plant photosynthesis ( Netondo et al., 2004 ; Guo et al., 2021 ). Previous studies have shown that salt stress affects plant photosynthesis, with chlorophyll and carotenoid contents decreasing as the salt content in young leaves increases ( Parida et al., 2002 ; Stepien and Johnson, 2008 ; Duarte et al., 2013 ).…”

Involvement of Calcium and Calmodulin in NO-Alleviated Salt Stress in Tomato Seedlings

“…Exogenous Ca 2+ was also found to promote the adaptive of Gleditsia sinensis Lam. under salt stress [ 32 ]. Meanwhile, GSNO+CaCl 2 treatment showed better growth than CaCl 2 or GSNO treatment alone in tomato seedlings under salt stress ( Figure 2 ).…”

Calcium nutrition nanoagent rescues tomatoes from mosaic virus disease by accelerating calcium transport and activating antiviral immunity

“…Calcium is an essential element in diverse biological processes, such as disease resistance and plant development ( Springer et al., 2007 ; Wang et al., 2015 ; Tian et al., 2020 ; Guo et al., 2021 ). Extensive studies have demonstrated that the calcium changes can mediate plant defense against pathogen infections, and many exogenous agents are able to increase TMV tolerance through calcium signaling pathway ( Lu et al., 2010 ; Li et al., 2019b ).…”