Different Rhizospheric pH Conditions Affect Nutrient Accumulations in Rice under Salinity Stress

Abstract

This study was conducted to determine the responses to saline-alkaline (SA) stress with regard to nutrient accumulation in two rice varieties having different tolerances to salt-stress. A salinity-tolerant landrace, Pokkali, and a salinity-sensitive variety, PTT1, were exposed to three levels of SA conditions, pH 7.0 (mild), pH 8.0 (moderate), and pH 9.0 (severe), under 50 mM Na stress. The results indicated that Pokkali had comparably greater SA tolerance than PTT1 owing to its higher biomass production. The maintenance of the lower Na/K ratio in Pokkali shoots was achieved by the higher expression of OsHKT1;5 encoding a Na+ transporter in the shoots, OsNHX1 encoding a tonoplast-localized Na+/H+ antiporter in the roots, and OsHAK16 encoding a K+ transporter in the roots under SA conditions. We propose that the high expression of Fe deficiency-responsive genes, OsIRT1, OsIRO2, OsYSL15, OsNAS1, and OsNAS2, in both rice varieties under all SA conditions should contribute to Fe homeostasis in the shoots. In addition, SA treatment increased the concentrations of Ca, Mn, Zn, and Cu in the roots but decreased their concentrations in the shoots of both varieties. Overall, the results indicated that high rhizospheric pH influenced nutrient uptake and translocation from the roots to the shoots in rice.

A Mitochondrial Localized Chaperone Regulator OsBAG6 Functions in Saline-Alkaline Stress Tolerance in Rice

“…Additionally, alkaline stress typically restricts the bioavailability of iron (Fe), zinc (Zn), and manganese (Mn) (Aloo et al 2023 ). Under saline-alkaline stress, the concentration of Fe in both the roots and shoots of rice significantly decreased (Li et al 2016b ), while that of Mn and Zn decreased in the shoots and Mn increased in the roots (Nampei et al 2021 ). Hence, we measured the concentration of sodium (Na), Fe, Mn, and Zn under normal and saline-alkaline stress conditions in kitaake, osbag6 mutants, and OsBAG6 complementation lines.…”

Effect of Lithium Slag Application on Saline–Alkali Soil Amelioration and Vegetable Growth

“…For radish cultivation, only the pH o CK1 and LS0.5 at the harvest stage was markedly higher than that in the pre-sowing stag (p < 0.05). Meanwhile, at harvest time, the pH of radish planting soils was observabl higher than those of roquette planting soils (p < 0.05), which may be related to the differen ability of vegetables to absorb salt [5,19]. With the growth of vegetables, the pH of the saline-alkali soil dropped.…”

“…Soil salinization resulting in land degradation has become a worldwide problem that limits the development of the agricultural industry and the sustainability of the ecological environment [1][2][3][4]. Saline-alkali soils usually contain alkaline salts, such as NaHCO 3 and Na 2 CO 3 , and their soil pH is above 8.5 [5]. According to the statistics data, many once-productive soils have become salt-affected wastelands, the problems of which occur within the boundaries of over 100 countries including China, Australia, India, Egypt, Iraq, Mexico, Pakistan, Syria, Turkey and the United States, etc.…”