Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (11): 1241-1250.DOI: 10.17521/cjpe.2021.0221

Special Issue: 红树林及红树植物

• Research Articles • Previous Articles     Next Articles

Effects of provenance on leaf structure and function of two mangrove species: the genetic adaptation to temperature

ZHANG Xiao-Yan1,2, WEE Kim Shan Alison1, KAJITA Tadashi3, CAO Kun-Fang1,2,*()   

  1. 1State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning 530004, China
    2Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530004, China
    3Iriomote Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa 9071541, Japan
  • Received:2021-06-09 Accepted:2021-08-31 Online:2021-11-20 Published:2021-09-29
  • Contact: CAO Kun-Fang
  • Supported by:
    National Natural Science Foundation of China(31670406);Bagui Scholar Talent Project of Guangxi(33600992001)

Abstract:

Aims Plant leaves have the ability to adjust phenotypic characteristics according to different environmental conditions. The adaptability of leaf traits to the environment directly affects the survival, distribution and migration of plants under climate change. With global warming, mangrove forests have been expanding to higher latitudes. However, there is still a lack of understanding about the genetic adaptation of leaf traits of different mangrove species to temperature variation of native habitats.
Methods The leaf anatomical structure and physiological function parameters of the seedlings from 6 provenances of Bruguiera gymnorhiza and 5 provenances of Kandelia obovata were measured, which were grown in a common garden. The relationships between the leaf anatomical traits and physiological function of mangrove seedlings were analyzed, and the genetic adaptation of two mangrove species to the temperature of provenance was analyzed.
Important findings The leaf thickness, thickness of palisade tissue, cuticle and epidermis of B. gymnorhiza seedlings were significantly negatively correlated with the mean annual temperature of their native habitats. Compared with the seedlings of B. gymnorhiza, the K. obovata seedlings had thicker leaf epidermis and cuticle, and the anatomical traits of K. obovata were not correlated with the annual average temperature of the provenances. Pooling the data of the seedlings of different provenances of the two species together, the palisade tissue and to a lesser extend spongy tissue were positively correlated with photosynthetic rate, suggesting an important role of palisade tissue for photosynthesis in mangroves. There was also a significant positive correlation between vein density and stomatal density, maximum stomatal conductance, revealing genetic adaptation for the balance between leaf transpirational demand and water supply. In conclusion, B. gymnorhiza showed the significant genetic adaptation to the temperature of the provenance, while K. obovata did not. The leaf anatomical structure of K. obovata adapts to the temperature of provenance through the persistent inheritance of stress resistance of leaf structure. The differences of leaf structure lead to the corresponding changes of physiological functions such as photosynthesis and maximum stomatal conductance of mangroves, which is conducive to the survival and reproduction of mangroves under the climate change.

Key words: provenance, mangrove, leaf anatomy, photosynthetic characteristics, temperature