Ion homeostasis and Na+ transport-related gene expression in two cotton (Gossypium hirsutum L.) varieties under saline, alkaline and saline-alkaline stresses

Abstract

The sensitivity of cotton to salt stress depends on the genotypes and salt types. Understanding the mechanism of ion homeostasis under different salt stresses is necessary to improve cotton performance under saline conditions. A pot experiment using three salt stresses saline stress (NaCl+Na2SO4), alkaline stress (Na2CO3+NaHCO3), and saline-alkaline stress (NaCl+Na2SO4+Na2CO3+NaHCO3) and two cotton varieties (salt-tolerant variety L24 and salt-sensitive variety G1) was conducted. The growth, ion concentrations, and Na+ transport-related gene expression in the cotton varieties were determined. The inhibitory effects of saline-alkaline stress on cotton growth were greater than that of either saline stress or alkaline stress alone. The root/shoot ratio under alkaline stress was significantly lower than that under saline stress. The salt-tolerant cotton variety had lower Na and higher K concentrations in the leaves, stems and roots than the salt-sensitive variety under different salt stresses. For the salt-sensitive cotton variety, saline stress significantly inhibited the absorption of P and the transport of P, K, and Mg, while alkaline stress and saline-alkaline stress significantly inhibited the uptake and transport of P, K, Ca, Mg, and Zn. Most of the elements in the salt-tolerant variety accumulated in the leaves and stems under different salt stresses. This indicated that the salt-tolerant variety had a stronger ion transport capacity than the salt-sensitive variety under saline conditions. Under alkaline stress and salt-alkaline stress, the relative expression levels of the genes GhSOS1, GhNHX1 and GhAKT1 in the salt-tolerant variety were significantly higher than that in the salt-sensitive variety. These results suggest that this salt-tolerant variety of cotton has an internal mechanism to maintain ionic homeostasis.

Saline–Alkaline Stress Resistance of Cabernet Sauvignon Grapes Grafted on Different Rootstocks and Rootstock Combinations

“…Saline-alkaline stress disrupts ion homeostasis in plants, and excessive levels of Na + in plants impede the uptake of other ions; the concentrations of these ions affect the chlorophyll content and photoelectron transfer, which affect photosynthesis [37]. Gupta et al that the wilting of plant leaves stems from the presence of excess Na + in the roots and leaves, which prevents water uptake, leads to water deficiency and osmotic stress, and affects normal plant growth [38].…”

An overview of salinity stress, mechanism of salinity tolerance and strategies for its management in cotton

“… A study showing the comparison between a salt tolerant and salt sensitive cultivar in terms of response of ion content and gene expression ( Sun et al., 2021 ) . …”

“…The CMO gene from Atriplex hortensis led to enhanced salt tolerance when overexpressed in cotton (Huijun et al, 2010). Under salt stress, several auxin-induced genes, such as GH3 (auxin-conjugating A study showing the comparison between a salt tolerant and salt sensitive cultivar in terms of response of ion content and gene expression (Sun et al, 2021) . enzyme) and IAA, were up-regulated, whereas genes involved in auxin metabolism (synthesis and degradation) and auxin signal transduction, such as ARF (auxin response factor) and AFB2, were down-regulated.…”

Effects of Bacillus amyloliquefaciens on volatile components and nutrient element contents of Mentha piperita L. grown under salt stress

“…Bacillus amyloliquefaciens affects salt-stressed plants through unknown methods. However, it known that salt stress impacts plant ion homeostasis and Na + transport-related gene expression (Sun et al 2021). PGPB, especially Ba, may affect ion homeostasis and gene expression in salt-stressed plants, improving salt tolerance.…”