Metabolomics analysis of rice responses to salinity stress revealed elevation of serotonin, and gentisic acid levels in leaves of tolerant varieties

Abstract

A GC-MS based analytical approach was undertaken to understand the metabolomic responses of seedlings of 2 salt sensitive (Sujala and MTU 7029) and 2 tolerant varieties (Bhutnath, and Nonabokra) of indica rice (Oryza sativa L.) to NaCl induced stress. The 4 varieties responded differently to NaCl treatment with respect to the conserved primary metabolites (sugars, polyols, amino acids, organic acids and certain purine derivatives) of the leaf of rice seedlings. However, there were significant differences in salt induced production of chorismic acid derivatives. Serotonin level was increased in both the salt tolerant varieties in response to NaCl induced stress. In both the salt tolerant varieties, increased production of the signaling molecule gentisic acid in response to NaCl treatment was noticed. Salt tolerant varieties also produced increased level of ferulic acid and vanillic acid. In the salt sensitive varieties, cinnamic acid derivatives, 4-hydroxycinnamic acid (in Sujala) and 4-hydroxybenzoic acid (in MTU 7029), were elevated in the leaves. So increased production of the 2 signaling molecules serotonin and gentisic acid may be considered as 2 important biomarker compounds produced in tolerant varieties contributing toward NaCl tolerance.

Metabolomics analysis of Cajanus cajan L. seedlings unravelled amelioration of stress induced responses to salinity after halopriming of seeds

“…The level of O-acetylsalicylic acid increased in response to salt stress in the leaves of a few varieties of rice seedlings. 19 The present findings suggest that in vivo production of O-acetyl salicylic acid has a predominant role in salt stress tolerance in the plant, probably acting as a signalling molecule.…”

“…Mixture of fatty acid methyl ester markers (2 µl) (internal retention index (RI) markers prepared using fatty acid methyl esters of C8, C10, C12, C14, C16, C18, C20, C22, C24, and C26 linear chain length dissolved in chloroform) was added. 37 GC-MS analysis (Agilent 5975C gas chromatography system) was performed 37 with little modification 19,38 following users' guide to calibrate method with FAME standards available on Fiehn GC-MS Metabolomics library-2008 (Agilent Chem Station, Agilent Technologies Inc., Wilmington, USA) using retention time locking method. HP-5MS capillary column (30 metres length, Duraguard of 10 metres, 0.25mm diameter; narrow bore and a film of 0.25µm) manufactured by Agilent J&W GC columns, USA was used for the analyses.…”

“…Metabolite accumulation in plants and secondary metabolism are not only closely related to plant growth, but are also controlled by other environmental factors. 15 Recent studies unveiled metabolomic responses to salinity stress in barley, 16 wheat, 17 maize, 18 rice, 19 tobacco, 20 soyabean, 21 tomato 22 and Arabidopsis. 23 Metabolomics approach has provided new ideas on stress physiology and physiological basis of salinity tolerance in plants.…”

Metabolomics: A Way Forward for Crop Improvement

“…Elevated levels of amino acid accumulation in tolerant genotypes were observed as compared to susceptible varieties. [146]. GC/MS-based metabolic profiling of barley roots under salt stress conditions revealed an increased production of organic acid, proline, sucrose, xylose, and maltose, which showed the salt tolerance mechanism in barley [147].…”

Differential adaptation strategies to different levels of soil water deficit in two upland and lowland genotypes of rice: a physiological and metabolic approach

“…Rice ( Oryza sativa L.) is a staple food for nearly half of the world's population . Soil water deficit is estimated to affect about 50% of the world rice production .…”