Elevated ozone levels affect metabolites and related biosynthetic genes
in tartary buckwheat
Abstract
Global climate change and the industrial revolution have increased the
concentration of tropospheric ozone, a photochemical air pollutant that
can negatively affect plant growth and crop production. In the present
study, we investigated the effects of O3 on the metabolites and
transcriptome of tartary buckwheat. A total of 37 metabolites were
identified by gas chromatography coupled with time-of-flight mass
spectrometry, and principal component analysis was performed to verify
the metabolic differences between non-treated and O3-treated Tartary
buckwheat. The levels of most metabolites (threonic acid, tryptophan,
sucrose, and raffinose) decreased significantly after the O3 treatment.
On the contrary, the levels of two anthocyanins, cyanidin 3-O-glucoside
and cyanidin 3-O-rutinoside, increased more than 11.36- and 11.43-fold,
respectively after the O3 treatment. To assess the effect of O3 on the
genomic level, we analyzed the expression of anthocyanin biosynthesis
pathway genes in O3-treated and non-treated buckwheat using quantitative
real-time reverse transcription PCR. We found that the expression of all
anthocyanin pathway genes increased significantly in the O3-treated
buckwheat compared to that in the non-treated buckwheat. Altogether, our
results suggested that O3 affected the transcripts and metabolites of
tartary buckwheat, which would eventually cause phenotypic changes in
plants.