###### Abstract  
Iron (Fe) is a vital nutrient for the development of many plants. Therefore, enhancing plant performance and production in relation to Fe deficiency is becoming a serious challenge. In this work, we intended to survey the effect of seed pretreatment with salicylic acid (SA) on oxidative status, phenolic composition, and related antioxidant activities in two varieties of _Sulla carnosa_ (Sidi KShlif: SK and Kalbia: KA) treated with different Fe concentrations. In unprimed plants, the levels of phenolic compounds were very distinguishable among the two varieties, being superior in KA compared to SK. Interestingly, priming KA seeds with SA under control conditions or deficient conditions (D+SA treatment) caused a decreasing tendency in the contents of total phenolic compounds (TPC) and total flavonoids (TFC), whereas an opposite behavior was observed in SK. Moreover, an improvement of hydroxcinnamic and flavonoid groups, in addition to antioxidant activities (TAC, DPPH\({}^{\bullet}\), \(\beta\)-carotene and FRAP), was markedly found in SK primed with SA. According to these findings, SA seed pretreatment had a beneficial effect on the metabolic performance of this species under different Fe supply, regardless of whether the intensity of improvement was related to Fe concentration applied, variety, as well as plant organ. The results suggest that SA can account for the effective modulation of the secondary metabolites metabolism in _S. carnosa_ plants to deal with the detrimental impacts of Fe deficiency. Fe deficiency; biotechnological tool; salicylic acid; UHPLC-DAD-ESI/MS\({}^{n}\); phenol compounds; antioxidant activities +
Footnote †: journal: Applied Sciences  
two mechanisms of Fe acquisition are revealed by Fe resistant genotypes, i.e., strategy I and strategy II. Strategy II is exported only by the Poaceae group, and it is based on the release by roots of Fe (III)-solubilizing compounds known as phytosiderophores (PS) [5]. In turn, strategy I plants belong to the non-graminaceous monocotyledons and dicotyledons species which are characterized by the increase of Fe reduction by plant roots owing to the stimulation of rhizosphere acidification, in addition to the accumulation of organic acids and/or release of chelating compounds, particularly phenolics [6]. However, it is crucial to note that these chelating compounds, such as organic acids, flavins, and phenolic compounds, play a crucial role in the mobilization of Fe in strategy I plants [7]. These bioactive metabolites are considered as efficient Fe chelators by inducing the dissolution of ferric hydroxide unavailable for plants in the rhizosphere [1; 3]. On the other hand, it is well known that Fe can display oxidative stress in plants, when present at both scarce and poisonous levels, essentially by damaging the functionality of the mitochondria photosynthetic chain [7], which boosts the formation reactive oxygen species [8]. To sustain damage from oxidative stress, plant resort to defense mechanisms, requiring namely enzymatic and non-enzymatic antioxidants [1; 5]. Among these substances, polyphenols are mainly relevant due to their significant antioxidant potential, in addition to their chelating properties. According to recent investigations [1; 6], these compounds produced in different plant tissues notably contributed to preserve reactive ROS under the toxic levels during abiotic/biotic stresses. Phenols content and composition can be affected when plants are subjected to biotic and abiotic restrictions [9]. In fact, environmental restrictions commonly have an opposite impact on the levels of phenolic compounds. The accumulation is usually accompanied by plant biomass decrease, essentially at the shoot level. Moreover, it is expected that the optimal yield of polyphenols is a typical feature of stress-tolerant species [10]. As expected by [PERSON] et al.