High Temperature Alters Secondary Metabolites and Photosynthetic Efficiency in Heracleum sosnowskyi

Due to global warming, invasive species have spread across the world. We therefore studied the impact of short-term (1 day or 2 days) and longer (7 days) heat stress on photosynthesis and secondary metabolites in Heracleum sosnowskyi, one of the important invasive species in the European Union. H. sosnowskyi leaves exposed to short-term heat stress (35 degrees C/1 d) showed a decrease in chlorophyll and maximum potential quantum efficiency of photosystem II (Fv/Fm) compared to control, 35 degrees C/2 d, or 30 degrees C/7 d treatments. In turn, the high level of lipid peroxidation and increased H2O2 accumulation indicated that the 30 degrees C/7 d stress induced oxidative damage. The contents of xanthotoxin and bergapten were elevated in the 2 d and 7 d treatments, while isopimpinellin was detected only in the heat-stressed plants. Additionally, the levels of free proline and anthocyanins significantly increased in response to high temperature, with a substantially higher increase in the 7 d (30 degrees C) treatment. The results indicate that the accumulation of proline, anthocyanins, and furanocoumarins, but not of phenolic acids or flavonols, contributes to protection of H. sosnowskyi plants against heat stress. Further studies could focus on the suppression of these metabolites to suppress the spread of this invasive species.

Automated summary

The study investigated the impact of short-term and longer heat stress on the photosynthesis and secondary metabolites in an important invasive species, Heracleum sosnowskyi. Results showed that high temperature induced physiological responses such as accumulation of proline, anthocyanins, and furanocoumarins, along with lipid peroxidation damage. Further research could focus on suppressing these metabolites to control the spread of this invasive species.