Metabolomics is a technology that generates large amounts of data and contributes to obtaining wide and integral explanations of the biochemical state of a living organism. Plants are continuously affected by abiotic stresses such as water scarcity, high temperatures and high salinity, and metabolomics has the potential for elucidating the response-to-stress mechanisms and develop resistance strategies in affected cultivars. This review describes the characteristics of each of the stages of metabolomic studies in plants and the role of metabolomics in the characterization of the response of various plant species to abiotic stresses.

Micropropagation techniques allow the mass production of banana plants but can cause somaclonal variations such as dwarfism. Changes in the metabolite profile during micropropagation of normal (NP) and dwarf (DP) banana plants have not been described. Both, NPs and DPs of banana Musa AAA cv. Williams were micropropagated and the metabolite profile of vitroplants was assessed at the proliferation (PP), rooting (RP) and the second greenhouse-acclimatization (APII) phases of tissue culture. Metabolites from 10 DPs and 10 NPs meristems from each micropropagation phase were extracted and identified by gas chromatography coupled with mass spectrometry (GC-MS). Principal component analysis (PCA) and test of statistical significance were applied to detect differentially accumulated metabolites. The PCA showed a clear grouping of DPs separated from NPs in RP and APII. Among the differentially accumulated metabolites, various precursors of apoplast components including arabinose and galactose or deoxygalactose in both PP and RP, as well as mannose and fucose in APII were under-accumulated in DPs. Results suggest affected apoplast composition during micropropagation of DPs.

BackgroundMicropropagation techniques allow the mass production of pathogen-free banana plants but can cause somaclonal variations (SV) such as dwarfism. Changes in the metabolite profile during micropropagation of true-to-type (normal) and dwarf banana plants have not been described. Normal and dwarf banana Musa AAA cv. “Williams” were micropropagated and the metabolite profile of vitroplants was assessed at the proliferation, rooting and greenhouse-acclimatization phases of tissue culture. Metabolites from 10 dwarf and 10 normal meristems from each micropropagation phase were extracted and detected by gas chromatography coupled to mass spectrometry (GC-MS). Principal component analysis (PCA) and test of statistical significance were applied to detect differentially expressed metabolites. ResultsThe PCA showed a clear grouping of the dwarf plants (DPs) separated from the normal plants (NPs) in the rooting and acclimatization phases. In the proliferation phase, L-sorbose was significantly more abundant in DPs when compared to NPs. In the rooting phase, the aerial parts of the DPs showed significantly higher levels of 2-Keto-d-gluconic and citric acids but lower levels of fructose when compared to NPs. The meristems of DPs from the acclimatization phase showed significantly higher levels of D-galactose, gulonic acid and D- galacturonic acid but lower levels of mannose and L-fucose when compared to the NPs. Some molecules, such as L-glutamin and uridin were only detected in NPs from this phase. ConclusionsResults suggest the presence of oxidative stress and changes in the constitution of the apoplast at the different stages potentially affecting cell shape and phenotypic traits in DPs.