Abstract:
The study aims to underpin biochemical mechanisms induced by the application of different concentrations of an amino-acid based Phytostim® biostimulant on growth and yield attributes. Different concentrations of Phytos- tim® biostimulant: 0 (untreated), 1, 3, and 6% were foliar applied on lettuce cultivars (‘Lara’ and ‘Elisa’). After
45 days of transplanting, analysis growth and yield attributes, biochemical analysis and LC-MS untargeted metabolites profile were performed. Application of 3% dose improved both growth and yield parameters in both cultivars in comparison to the 6% dose which inhibited growth. Similar trend was observed for biochemical and
antioxidant analysis (phenolic, flavonoids, carotenoids, chloroplyll a and b and scavenging activity). The PCA and OPLS-DA score-plot clustered the metabolome profile of biostimulant treated vs untreated samples with major heterogeneity distinction observed in the untreated samples. Obtained results validate the use of bio-
stimulants in agriculture while giving information on the effects of the treatments towards changes in the chemical composition within the studied cultivars.
