PJB-2020-53
Na+ and K+ homeostasis is important for salinity and drought tolerance of Calligonum mongolicum
Jing Hu, Xiaoke Hu, Huirong Duan, Huiwen Zhang and Qiushi Yu
Abstract
Calligonum mongolicum is a typical pioneer xerophyte for sand fixation. To unravel the drought and salt tolerance of C. mongolicum, salt and drought stress were simulated by NaCl and sorbitol treatments respectively, and the accumulation and distribution of Na+, K+ in C. mongolicum were analyzed. The results showed that the fresh weight, dry weight and relative growth rate of C. mongolicum were increased significantly under the treatment of 25 mM NaCl, suggesting that 25 mM NaCl could promote plant growth. The addition of 50-300 mM NaCl increased sharply Na+ concentration in roots and shoots, while K+ concentrations remained stable; further study found that the 25-100 NaCl treatment significantly increased the net K+ uptake rate. Moreover, compared with moderate salt stress (25 mM NaCl), as the degree of stress intensified (50 and 100 mM NaCl), the ST value improved evidently. Therefore, it is suggested that C. mongolicum is able to maintain K+ homeostasis, thus refrain from K+ insufficiency brought by the external Na+ competition to resist salt stress. Under -0.25 – -1.0 MPa treatments, net Na+, K+ uptake rate was increased significantly, but Na+/K+ ratio, ST value and Na+, K+ relative distribution in tissues of C. mongolicum remained stable, implying that maintaining Na+, K+ homeostasis may be especially significant for C. mongolicum to deal with drought.
To Cite this article:
Hu, J., X. Hu, H. Duan, H. Zhang and Q. Yu. 2021. Na+ and K+ homeostasis is important for salinity and drought tolerance of Calligonum mongolicum. Pak. J. Bot., 53(6): DOI: http://dx.doi.org/10.30848/PJB2021-6(13)
Download
