The effect of salinity stress on Na+, K+ concentration, Na+/K+ ratio, electrolyte leakage and HKT expression profile in roots of Aeluropus littoralis

Document Type: Research Paper


1 Department of Plant Biotechnology, University of Jahrom, Iran

2 Department of Plant Breeding and Biotechnology, Ferdowsi University of Mashhad, Iran

3 Institute of Biotechnology, Collage of Agriculture, Shiraz University, Iran

4 Department of Plant Breeding and Biotechnology, Shirvan University, Iran


Among abiotic stresses, salinity has been increasing over the time for many reasons like using chemical fertilizers, global warming and rising sea levels. Under salinity stress, the loss of water availability, toxicity of Na+ and ion imbalance directly reduces carbon fixation and biomass production in plants. K+ is a major agent that can counteract Na+ stresses, thus the potential of plants to tolerate salinity is strongly dependent on their potassium nutrition. HKTs (High-affinity K+ Transporters) are a family of transporters that mediate Na+-specific or Na+-K+ transport and play a key role in the regulation of ion homeostasis. In this study, we intended to focus on Electrolyte Leakage, ratio of K+/Na+, transcriptomic responses of a subclass two HKT in the roots of Aeluropus littoralis under salt stress. We investigated a noticeably different expression pattern over studied time points and found a snappy increase of AlHKT and rebalance of K+ concentration. It can be suggested that the early and high response of a Na+-K+ coupled transporter acted as a part of A. littoralis salt tolerance.


Main Subjects

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