Responses of barley to hypoxia and salinity during seed germination, nutrient uptake, and early plant growth in solution culture

Abstract

The resistance of most plants to salt can be impaired by concurrent waterlogging. However, few studies have examined this interaction during germination and early seedling growth and its implications for nutrient uptake. The aim of the study was to examine the response of germination, early growth, and nutrient uptake to salt (NaCl) and hypoxia applied to barley (Hordeum vulgare L. cv. Stirling), in solution culture. Hypoxia, induced by covering seeds with water, lowered the germination from 94% to 28% but salinity and hypoxia together lowered it further to 13% at 120 mM NaCl. While the germination was 75% at 250 mM NaCl in aerated solution, it was completely inhibited at this NaCl concentration under hypoxia. Sodium ion (Na + ) concentrations in germinated seedlings increased with increasing salinity under both aerated and hypoxic conditions during germination, while K + and Mg + concentrations were decreased with increasing salinity in 6 d old seedlings. After 20 d, control seedlings had the same dry weights of the roots and shoots with and without hypoxia but at 10 mM NaCl and higher, shoot and root dry weight was depressed with hypoxia. Sodium ion increased in roots and shoots with increased NaCl under both aerated and hypoxic conditions while K + was depressed when salinity and hypoxia were applied together and Ca 2+ was mostly decreased by NaCl. In general, hypoxia had greater effects on nutrient concentrations than NaCl by decreasing N, P, S, Mg, Mn, Zn, and Fe in shoots and by increasing B concentrations. The threshold salinity levels decreased markedly for germination, uptake of a range of nutrients, and for seedling growth of barley under hypoxic compared to well-aerated conditions.

Growth, ionic homeostasis, and physiological responses of cotton under different salt and alkali stresses

“…The absorption of nutrients by plants is inhibited by salt–alkali stress 46 , 47 , and the lack of a particular nutrient element changes the metabolism of plants and affects the biosynthesis of metabolites. Salt stress is primarily caused by excess salt ions in soil, and rebuilding ion homeostasis under salt–alkali stress remains an important salt-tolerance strategy in plant cells 13 , 48 .…”

De Novo Transcriptome Characterization, Gene Expression Profiling and Ionic Responses of Nitraria sibirica Pall. under Salt Stress

“…In the current study, the Na/K ratios in the leaves and stems were higher than that in the roots, which is similar in Tibetan wild barley under salt stress [62], indicating that maintaining an optimal Na/K ratio could improve salt tolerance. Kirmizi and Bell [71] reported that nutrient element uptake and distribution in plant tissues are affected by salt stress. In this study, we also found that Ca, Cu, Fe, Mg, and K contents decreased in roots, stems and leaves under salt stress.…”

Assessment of phytotoxicity of treated water of Tabuk wastewater plant by different technologies on seed germination of chick pea (Cicer arietinum)

“…The negative effect of the T6 water on seed germination of Cicer may be attributed to the high TDS, conductivity and chloride content. There are reports that suggests seed germination is negatively affected by salinity through osmotic effects (Zhang et al 2010;Krmz & Bell 2012), by ion toxicity (Hampson & Simpson 1990) or by a combination of the two (Huang & Redmann 1995).…”