Plant Diversity ›› 2015, Vol. 37 ›› Issue (01): 46-54.doi: 10.7677/ynzwyj201514037

• Articles • Previous Articles     Next Articles

The Thermotolerance and Repair Mechanism of Photosystem in Alpine Plant Arabis paniculata (Cruciferae)*

 TANG  Ting-1、2, ZHENG  Guo-Wei-1, LI  Wei-Qi-1   

  1. 1 Germplasm Bank of Wild Species in Southwest China, Kunming Institute of Botany, Chinese Academy of Sciences,
    Kunming 650201, China; 2 University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2014-03-12 Online:2015-01-25 Published:2014-06-11
  • Supported by:

    NSFC (31300251) and XiBuZhiGuang Project

Abstract:

The heat stress associated with extremely and moderately high temperatures affects a series of physiological activities in plants especially photosynthesis. However, it is proposed that the plants use different photosynthetic strategy to deal with extreme and moderate heat stresses. Most reports focus on the cold tolerant ability but thermotolerance of alpine plants. In the present study, we used the alpine plant Arabis paniculata as a model alpine plant to examine whether its capacity for heat tolerance is exhibited under moderate heat stress and, if so, how this capacity is related to differences in its photosynthesis compared with that of its close relative Arabidopsis thaliana. We found that Apaniculata had high photochemical efficiency at a moderately high temperature and a rapid reversible recovery process, which reflected substantial heat tolerance. Despite no obvious difference in F0 between the two species, the higher Fm values after heat treatment and recovery in Apaniculata than in Athaliana facilitated the rapid photochemical recovery. A rapid and transient increase in nonphotochemical quenching after moderate heat stress provided timely protection for PSII against the damage caused by heat and light. The rapid accumulation of heat shock protein 101 upon exposure to moderately high temperatures might initiate photochemical repair. Finally, the high rate of survival of Apaniculata after severe heat treatment attested to the substantial heat tolerance of its photosynthetic machinery under moderate stress. Our results indicated that a highly heattolerant photosystem and effective photochemical repair mechanism contribute to the capacity of Apaniculata to tolerate moderate heat stress.

Key words:  Heat stress, Moderate heat stress, Photosynthesis, Arabis paniculata, Non-photochemical quenching, Heat shock protein

CLC Number: 

  • Q 945