Effects of Differential Salt Stress on Seed Germination and Seedling Physiological-Biochemical Characteristics in Pedicularis kansuensis
摘要
To improve saline-alkaline land utilization and ecosystem stability, selecting plant species with high salt tolerance is crucial Pedicularis kansuensis Maxim, a hemiparasitic plant native to the Qinghai-Tibet Plateau, shows potential for ecological restoration, though its salt tolerance remains unclear. This study investigated the effects of salt stress (30, 60, 90, 120 mmol L−1) on seed germination and seedling physiology of P. kansuensis. Results showed that salt stress significantly inhibited seed germination and seedling growth. Germination rate, germination potential, and vigor index decreased with increasing salt concentration. Physiological indices such as superoxide dismutase activity increased continuously, while peroxidase, catalase, malondialdehyde, soluble sugar, and soluble protein contents initially increased and then decreased, peaking at 60 mmol L−1. Aboveground tissues were more sensitive to salt stress than roots. We conclude that P. kansuensis can tolerate mild to moderate salt stress (up to ~60 mmol L−1) but is unsuitable for highly saline environments. These findings provide insights into its potential use in revegetation of moderately salinized grasslands.