Screening of Iranian Tarragon Accessions Based on Physiological and Phytochemical Responses Under Water Deficit: Applications for Development and Breeding

In this study, screening of tarragon accessions based on physiological and phytochemical traits was investigated under water deficit. The compounding impacts of water deficit * accessions significantly altered the chlorophyll and carotenoid contetnt, malondialdehyde, electrolyte leakage, superoxide dismutase, catalase and ascorbate peroxidase. The HPLC analyse revealed the presence of chlorogenic, syringic, ferulic, vanilic, chicoric and p -coumaric acids as major phenolic acids, while quercetin and herniarin were detected as the predominant flavonoid and coumarin compounds in the extracts. The quality and quantity of tarragon secondary metabolites were impacted by water deficit, suggesting that drought stress either increased the amounts of some common compounds or introduced some new compounds that were not present under normal conditions. In some genotypes, the content of some secondary metabolites in tarragon had the highest values under severe water deficit stress. The results indicated that Hamadan, Varamin and Estahbanat accessions could be introduced as tolerant accessions. Due to the very different response of tarragon accessions to water deficit and the existence of diversity between these accessions, the findings of the present study could be an effective step in identifying and achieving homogeneous, drought-tolerant and high-yield potential accessions, and may help tarragon breeding programs and development of cultivation.