Steviol glycosides targeted analysis in leaves of Stevia rebaudiana (Bertoni) from plants cultivated under chilling stress conditions

Stevia rebaudiana is an important agricultural crop for the production of a high-potency natural sweetener, sensitive to low temperature during the developmental stage. Stimulation of chilling stress with a pre-treatment with endogenous signalling components and in particular with salicylic acid (SA), hydrogen peroxide (H2O2), 6-benzylaminopurine (BAP) and calcium chloride (CaCl2) could induce tolerance to chilling and could constitute a suitable way to maintain quality and quantity of steviol glycosides under controlled artificial environment. In the present work the effects of different putative signalling molecules on the morpho-physiological parameters were evaluated, and a specific method for the quali-quantitative analysis of steviol glycosides in S. rebaudiana plants cultivated under controlled conditions was developed, by using LC-ESI-FT (Orbitrap) MS, LC-ESI-QqQ-MS/MS and multivariate data analysis. This approach underlined that the pre-treatment has influence on the production of secondary metabolites. In particular Stevia plants characterised by higher contents of rebaudioside A and stevioside, were identified.