Physiological response of Kobresia pygmaea to temperature changes on the Qinghai-Tibet Plateau

Background The Qinghai-Tibetan Plateau is experiencing rapid climate warming, which may further affect plant growth. However, little is known about the plant physiological response to climate change. Results Here, we select the Kobresia pygmaea, an important perennial Cyperaceae forage, to examine the physiological indices to temperature changes in different growing months. We determined the contents of malondialdehyde, proline, soluble sugars, superoxide dismutase, peroxidation, and catalase activity in leaves and roots of Kobresia pygmaea at 25celcius, 10celcius, 4celcius and 0celcius from June to September in 2020. The results showed that the content of osmotic adjustment substances in the leaves and roots of Kobresia pygmaea fluctuated greatly with experimental temperature in June and September. The superoxide dismutase activity in the leaves and roots of the four months changed significantly with temperatures. The peroxidation activity in the leaves was higher than that in the roots, while the catalase activity in leaves and roots fluctuates greatly during June, with a relative stable content in other months. Membership function analysis showed that higher temperatures were more harmful to plant leaves, and lower temperatures were more harmful to plant roots. The interaction of organs, growing season and stress temperature significantly affected the physiological indicators. Conclusions The physiological indicators of Kobresia pygmaea can actively respond to temperature changes, and high temperature can reduce the stress resistance Kobresia pygmaea. Our findings suggest that the Kobresia pygmaea has high adaptability to climate warming in the future.

Automated summary

This study investigated the physiological responses of Kobresia pygmaea, an important perennial Cyperaceae forage, to temperature changes. The results showed that the content of osmotic adjustment substances, as well as the activities of superoxide dismutase and peroxidation, fluctuated greatly with experimental temperature in different growing months. Higher temperatures were found to be more harmful to plant leaves, while lower temperatures were more harmful to plant roots. The physiological indicators of Kobresia pygmaea actively responded to temperature changes, and high temperature reduced its stress resistance. Overall, our findings suggest that Kobresia pygmaea has high adaptability to climate warming in the future.