Effects of exogenous amino acids on yttrium uptake and accumulation in tomato (Solanum lycopersicum).

Abstract

This study investigated the impacts of exogenous amino acid supplementation on the uptake, translocation, and accumulation of yttrium (Y) in tomato plants (Solanum lycopersicum). To understand how amino acids enhance nutrient uptake and plant growth by using Hoagland nutrient solution. The results indicated that the combination of Y with glutamic acid (Y + Glu) significantly increased Y concentration in the leaves to 28.5 ± 1.42 µg g^-1, while the combination with histidine (Y + His) resulted in a markedly lower concentration of 2.7 ± 0.06 µg g^-1. Notably, glutamic acid proved to be particularly effective in enhancing Y accumulation in xylem sap. The control plants exhibited a higher xylem sap flow rate of 0.27 ± 0.008 g h^-1, which was significantly greater than those treated with amino acids (p < 0.05). Histidine levels were elevated in the Y + His treatment, reaching 194.78 ± 13.79 μmol L^-1, while tryptophan and aspartic acid showed their highest concentrations in their respective treatments at 109.92 ± 14.43 μmol L^-1 and 212.95 ± 13.65 μmol L^-1. These findings demonstrated that amino acid supplementation substantially enhanced the phytoextraction of Y in tomato plants, through the application of glutamic acid. Further exploration into the molecular mechanisms governing Y complexation and transport within plants through phytoremediation is needed.