Metabolic profile of two different Cichorium spinosum L. ecotypes as influenced by nitrogen form and supply levels
Cichorium spinosum L., commonly known in Greek as stamnagathi, is considered as a health-promoting vegetable. Although stamnagathi is a native species that is being harvested for private consumption, it has been recently developed as a commercially cultivated species, particularly in the island of Crete. Here, seeds of two different local landraces, originating from different regions of Crete, namely Stavros in Akrotiri and the Tavri Mountain in Sfakia, were propagated and grown hydroponically. Plants received nutrient solutions with different N concentration (4 or 16 mmol L‑1) and N source (NH4+/-N/total-N: 0.05, 0.25 or 0.50). Due to its pivotal nutritional value and its correlation to the plants' metabolic composition, we examined the effects of the different N supplementation regimes on the metabolism of the two landraces. Comparative GC/EI/MS metabolomics combined with bioinformatics analyses were conducted on the top five fully expanded leaves of each plant and more than 150 metabolic features were recorded. Results revealed that the genotypic composition was the predominant factor for the observed discrimination followed by the N treatments. Many of the identified metabolites play key roles in plant physiology (e.g., trehalose, a-linolenate), are bioactive, or important for their nutritional value (e.g., carbohydrates, amino acids, fatty acids). Differences in both total-N and NH4-N/total-N levels had clear effects on the plants' metabolism with various metabolites belonging to several biosynthetic pathways being synthesized in higher or lower levels following the treatments. Results confirmed the applicability of GC/EI/MS metabolomics in the assessment of the effects of different N fertilization regimes on stamnagathi metabolic composition. The information obtained could be used for the improvement of cultivation techniques for the hydroponic production of superior quality vegetable products.
Chatzigianni, M., Ntatsi, G., Livieratos, I., Aliferis, K.A. and Savvas, D. (2020). Metabolic profile of two different Cichorium spinosum L. ecotypes as influenced by nitrogen form and supply levels. Acta Hortic. 1268, 51-58
local landraces, metabolomics, trehalose, carbohydrates, N stress, stamnagathi