Objective To investigate the effects of foliar spray of selenite on metabolome in the leaves of Torrey grandis seedlings and changes in levels of secondary metabolites in the leaves.

Method Sodium selenite of 100 μg·L⁻¹ was sprayed to the leaves of 2-year-old seedlings of T. grandis at an interval of 15 days. 15 days after the second spraying, one-year-old leaves were harvested for metabolome analysis.

Result The results showed that there were 909 differential metabolites between treatment group and control under positive ionization mode, with 69 metabolites of significant changes (27 metabolites up-regulated and 42 metabolites down-regulated). Under negative ionization mode, 433 differential metabolite occurred between treatment group and control, with 43 differential metabolites of significant changes (11 metabolites up-regulated and 32 metabolites down-regulated). Some metabolites beneficial to human health increased significantly in the treated leaves of T. grandis seedlings, such as plantagoside (increasing 2.827 times as control), ligustilide (increasing 2.524 times) , 6-sialyllactose (increasing 2.021 times), and azilsartan (increasing 1.931 times).

Conclusion The results indicate that selenite foliar application on the leaves of T. grandis can increase biosynthesis of beneficial metabolites and accumulation in their leaves.