Our results showed that the content of S, P, Cu, Na, Zn, Mn, Fe, and K is higher in the shoot of Ti-treated Arabidopsis plants than in the untreated control ( Figure 3C). These **data** are similar to those reported for other plant species showing that Ti enhances the accumulation of different elements in plant tissues (Konishi and Tsuge, 1936;Carvajal and Alcaraz, 1995;Frutos et al., 1996;Wojcik and Wojcik, 2001;Hrubýet al., 2002;Alcaraz-Lopez et al., 2004;Haghighi et al., 2012;Kleiber and Markiewicz, 2013;Servin et al., 2013;Daghan et al., 2020;Ghazi et al., 2021). The increase of the content of essential elements in Ti-treated Arabidopsis plants correlates well with our RNA-seq **data** that shows that several genes encoding N, K, S, and divalent cations transporters, as well as P-starvation responsive genes are activated by Ti treatment ( Figure 5A, Supplementary Figure S5). The enhanced Pi content and the reduction in the uptake of toxic elements such as Al, and Cd could be explained by the increased expression of genes encoding organic acid transporters in Titreated plants. Organic acid exudation has been shown to enhance Pi uptake and ameliorate Al toxicity by preventing its entry into the root (Hocking, 2001;Barcelóand Poschenrieder, 2002;Santos et al., 2014). Our **data** shows that the root exudates of Ti-treated plants have a higher capacity to solubilize Pi from insoluble compounds and higher chelation of metallic ions (Supplementary Figure S2). These results suggest that treatment with 2 mM Ti enhances plant nutrition which is reflected in better growth. However, as we described before, higher Ti concentrations (8 mM) have a drastic effect on Arabidopsis growth, which could be due to a direct toxic effect of Ti or an indirect effect mediated by an exacerbated accumulation of some elements in the plant such as Na or Fe. According to White and Brown (2010), Na, Cl, B, Fe, and Mn are toxic at high concentrations. Considering that in Ti-treated plants the increased Pi accumulation was directly correlated with the amount of Ti applied ( Figure 1C, D), other elements may be hyperaccumulated at high Ti concentrations. This elemental hyperaccumulation could be responsible, at least in part, of the toxic effect of Ti at high concentrations.