Author

Beby Panwar, Salim Salim, Shivani Chauhan, Nisha Singh*, Maneesh Kumar Lomas, Amit Kumar, Ishwar Singh**, Shivani Sangal

Abstract

Fourier transform infrared (FTIR) spectroscopy was used to study the biochemical changes in Hordeum vulgare L. under neutral (NaCl) and alkaline (Na₂CO₃) salinity stress at concentrations of 50, 100, 150, and 200 mM. The comparative spectral analysis showed key functional groups such as alcohols, aldehydes, alkanes, amides, amines, and carboxylates across all treatments. These groups play a crucial role in helping individuals adapt to stress. However, there were specific variations in minor functional groups based on stress type. Aromatic azo compounds and hetero rings were expressed inconsistently under alkaline stress. In addition, Na₂CO₃ caused a significant reduction in C=S, Si-O-C, and sulfur-containing groups like sulphates, sulphonamides, sulfones, and sulfonic acids at higher concentrations. In contrast, NaCl preserved most functional groups even under severe stress. Carboxylic acids were missing in all treatments, which implies they may have converted to their salt forms in saline conditions. These results indicate that alkaline salinity causes more severe biochemical disruption than neutral salinity, particularly affecting sulfur metabolism and the formation of heterocyclic compounds. FTIR profiling offers a quick, non-destructive way to distinguish between types of salinity and their effects on plant biochemistry. This helps identify stress-specific biomarkers and tolerance mechanisms in barley.

Pages:97-102

Doi Number 10.61289/jibs2026.11.10.0536

Keywords Salinity stress, Fourier transform infrared spectroscopy, Barley.