Physiological and agronomical traits effects of titanium dioxide nanoparticles in seedlings of Solanum lycopersicum L.

BACKGROUND

Titanium dioxide nanoparticles (TiO NPs) have been reported to have contrasting effects on plant physiology, while their effects on sugar, protein, and amino acid metabolism are poorly understood. In this work, we evaluated the effects of TiO NPs on physiological and agronomical traits of tomato (Solanum lycopersicum L.) seedlings. Tomato seeds were treated with TiO NPs (1000 and 2000 mg L), TiO microparticles (µPs, 2000 mg L) as the size control, and ultrapure water as negative control.

RESULTS

The dry matter of stems (DMs), leaves (DMl) and total dry matter (DMt) decreased as particle concentration increased. This trend was also observed in the maximum quantum yield of light-adapted photosystem II (PSII) (F´/F´), the effective quantum yield of PSII (ΦPSII), and net photosynthesis (P). The concentrations of sugars, total soluble proteins, and total free amino acids were unaffected, but there were differences in the daily dynamics of these compounds among the treatments.

CONCLUSION

Our results suggest that treating tomato seeds with TiO might affect PSII performance, net photosynthesis and decrease biomass production, associated with a concentration- and size-related effect of TiO particles.