Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (2): 249-261.DOI: 10.17521/cjpe.2022.0167

• Research Articles • Previous Articles     Next Articles

Divergent responses of non-structural carbohydrates in Phoebe bournei and Schima superba to different heat wave patterns

YU Hai-Xia1, QU Lu-Ping1,*(), TANG Xing-Hao2, LIU Nan1, ZHANG Zi-Lei1, WANG Hao1, WANG Yi-Xuan3, SHAO Chang-Liang3, DONG Gang4, HU Ya-Lin1   

  1. 1Forestry College, Fujian Agricultural and Forestry University, Fuzhou 350002, China
    2Fujian Academy of Forestry, Fuzhou 350012, China
    3Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
    4School of Life Science, Shanxi University, Taiyuan 030006, China
  • Received:2022-04-26 Accepted:2022-09-05 Online:2023-02-20 Published:2023-02-28
  • Contact: *(fatqlp@163.com)
  • Supported by:
    National Natural Science Foundation of China(32171749);National Natural Science Foundation of China(31800512);National Natural Science Foundation of China(31870466);Fujian Provincial Seed Industry Innovation and Industrialization Project(ZYCX-LY-202102);National Key R&D Program of China(2016YFD0600603-2)

Abstract:

Aims The storage and regulation mechanisms of non-structural carbohydrates (NSC) in plants reflect the response of plant growth and metabolism to environmental changes. In the scenario of global warming, the increasing frequency of extreme climate events such as heat wave, which is bound to affect the carbon budget and carbon distribution of plants. However, the effects of complex heat wave patterns (different frequency and interval time) on the distribution and regulation mechanism of NSC among different plant organs are still unclear. The objective of this study is to elucidate the mechanism of carbon budget at the level of plant organs under heat waves.

Methods We conducted the simulated heat wave events through the combined action of open top chamber (OTC) and electric heater to examine the changes and distributions of NSC content and biomass among organs (stems, leaves and roots) of Phoebe bournei and Schima superba.Five different heat wave frequency and interval treatments were set, including no heat wave (CK), one heat wave (HW), two heat wave interval of 7 days (2HW7), two heat wave interval of 30 days (2HW30) and two heat wave interval of 45 days (2HW45).

Important findings (1) The repeated heat wave (2HW7)significantly increased soluble sugar content in stems of P. bournei, but had no significant effect on soluble sugar and NSC contents in roots and leaves. 2HW7 significantly increased starch content in the stem and root of S. superba, but had no significant effect on soluble sugar and NSC contents. These results indicated that the NSC allocation and regulation in different broad-leaved tree species and organs response to heat waves were divergent. (2) NSC content in P. bournei stem under 2HW30 and 2HW45 were significantly lower than 2HW7, and starch content in S. superba stem and root were also significantly lower than 2HW7, which was no significant difference with CK. These results suggested that multiple heat waves exist a cumulative effect. The magnitude of the cumulative effect was closely related to the heat wave interval time. (3) The biomass of all P. bournei organs in 2HW7 treatment group was significantly increased, while the biomass of stem and root of S. superba showed no significant differences under different heat wave patterns, suggesting that P. bournei increased the storage of NSC and distributed to all organs to resist the heat wave stress, while S. superba stored photosynthetic products as starch only in leaf to resist the heat wave stress. Our results revealed that heat waves with different frequencies and intervals had an accumulative effect on plants, and the ability of plant to cope with heat wave stress via regulating NSC content in different organs was related to the accumulative effect.

Key words: heat wave, cumulative effect, extreme climate, non-structural carbohydrate, carbon balance