Background: Gnetum parvifolium
stems and roots have been used for a long time in traditional Chinese medicines.
Stilbenes are bioactive compounds present in
G. parvifolium plants, and they possess antioxidative and anticancer
properties. However, little is known about the responses of
G. parvifolium stilbene biosynthetic pathways to
stress conditions. Therefore, we investigated stilbene biosynthesis, including the expression of relevant genes,
in
G. parvifolium exposed to high-temperature and ultraviolet-C treatments.
Results: High temperatures did not influence the accumulation of total stilbenes in stems but decreased stilbene
concentrations in roots at 3 h, with a subsequent restoration to control levels. In contrast, ultraviolet irradiation
induced the accumulation of total stilbenes in stems but not in roots. We also observed that high temperatures
inhibited the production of resveratrol and piceatannol in
G. parvifolium stems and roots, whereas ultraviolet
treatments initially inhibited their accumulation (up to 6 h) but induced their production at later time points.
Analyses of specific genes (i.e.,
PAL,
C4H,
4CL,
STS, and
CYP) revealed that their expression levels generally
increased in stress-treated stems and roots, although there was some variability in the expression profiles
during treatments.
Conclusions: Our results indicated that high temperatures and ultraviolet irradiation differentially affect the
biosynthesis of specific stilbenes in
G. parvifolium stems and roots. Therefore, cultivating
G. parvifolium
seedlings under optimal stress conditions may increase the biosynthesis of specific stilbene compounds.
