Plant Diversity ›› 2014, Vol. 36 ›› Issue (05): 595-602.doi: 10.7677/ynzwyj201413106

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Changes of Membrane Stability in PotassiumStressed Plants

WANG Dan-Dan-1、2, ZHENG Guo-Wei-1, LI Wei-Qi-1、3   

  1. 1 The Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; 2 University of Chinese Academy of Sciences, Beijing 100039, China; 3 Biology Department, Honghe University, Mengzi 661100, China
  • Received:2013-05-05 Online:2014-09-25 Published:2013-07-15
  • Supported by:

    The National Natural Science Foundation of China (NSFC 30670474, 30870571 and 31070262)

Abstract:

The maintenance of membrane function is critical to the ability of plants to resist environmental stresses; specifically, the stability and appropriate fluidity of membranes are crucial to their normal function. We previously demonstrated that plants adapt to longterm potassium (K+) deficiency by accumulation of membrane lipids in leaves and maintenance of the lipid composition in roots. In this study, which involved Arabidopsis thaliana and its K+deficiencytolerant relative Crucihimalaya himalaica, we first calculated the doublebond index (DBI) as an indicator of membrane fluidity. After exposure to longterm K+deficiency stress, the DBI of the total lipids in leaves of Athaliana and Chimalaica showed no significant changes, whereas the DBI of the total lipids in the roots of these species showed slight increases. Changes in lysophospholipids (lysoPLs) levels, and digalactosyldiacylglycerol/monogalactosyldiacylglycerol (DGDG/MGDG) and phosphatidylcholine/phosphatidylethanolamine (PC/PE) ratios, all of which strongly reflect membrane stability, were also studied in K+stressed Athaliana and Chimalaica. After longterm K+ deficiency, total lysoPLs levels increased in Athaliana and Chimalaica leaves, but showed no significant changes in roots. DGDG/MGDG and PC/PE ratios were higher in Chimalaica leaves and roots than in those of Athaliana. These results indicate that Chimalaica exhibits superior membrane stability compared with Athaliana. This may explain its superior growth and tolerance under K+deficient conditions.

Key words: Crucihimalaya himalaica, Arabidopsis thaliana, Tolerance of K+ deficiency, Membrane fluidity, Membrane stability

CLC Number: 

  • Q 945