Physiological and Proteomic Analyses Reveal Adaptive Mechanisms of Ryegrass (Annual vs. Perennial) Seedlings to Salt Stress

Abstract

Ryegrass has a relatively high salt tolerance and is considered to be a promising species for both foraging and turf purposes in salt-affected soils in China. While annual ryegrass and perennial ryegrass are two different species, they have similar genomes. However, little is known about their physiological and molecular response mechanisms to salinity stress. Here, biomass, chlorophyll fluorescence, and inorganic ion and organic solute content were measured. 2-DE-based proteomic technology was then used to identify the differentially expressed proteins in the salt-treated seedlings. The results showed that salt stress reduced growth and photosynthesis in the seedlings of both species, but much more so in annual ryegrass. With increasing salinity, the Na+ concentration increased while the K+ concentration decreased in both species, and the sugars and proline increased as the primary organic solutes used to cope with osmotic stress. Additionally, proteomic analysis revealed 33 and 37 differentially expressed proteins in annual and perennial ryegrass, respectively. Most of the identified proteins were involved in carbohydrate and energy metabolism, photosynthesis, genetic information processes, amino acid metabolism, stress defense, and protein synthesis and folding. The results suggest that the two-ryegrass species had different physiological and proteomic responses. These findings can provide new insights into physiological mechanisms by which ryegrass species respond to salt stress.

Physiological and Proteomic Analysis of Seed Germination under Salt Stress in Mulberry

“…Additionally, the abundance of NaHCO 3 and NaCl was reduced in ribosomal proteins in tomato [102] and Arabidopsis [103]. Moreover, 30S ribosomal protein S1 in annual ryegrass and 50S ribosomal protein in perennial ryegrass decreased under salt stress, which affected the folding and synthesis of protein in annual and perennial ryegrass [104]. In this study, many of the proteins involved in protein synthesis were significantly downregulated, including the ribosomal protein family 30S ribosomal protein S21 (W9SIU2), 50S ribosomal protein L28 (W9QPT4), 50S ribosomal protein L34 (W9QWL4) and 60S ribosomal protein L28-1 (W9QUV3), indicating that the protein synthesis mechanism of mulberry is inhibited by salt stress during seed germination, thus affecting protein folding and synthesis.…”

Root Proteomic Analysis of Two Grapevine Rootstock Genotypes Showing Different Susceptibility to Salt Stress

“…According to studies conducted in other plant species, the capability to sequestrate Na + into the vacuole appears to play a key role in the salt response also in the roots of this woody plant. The capability to sustain the energy cost required by the salt-protective mechanisms is a very central point in the response [33,72]. In this context, the M4 genotype turned-out to better sustain the pathways involved in the synthesis of ATP and NADPH.…”