Chin J Plant Ecol ›› 2013, Vol. 37 ›› Issue (9): 830-838.DOI: 10.3724/SP.J.1258.2013.00087

• Research Articles • Previous Articles     Next Articles

Effects of sand burial on growth in two psammophyte seedlings and differences in their physiological responses

ZHAO Ha-Lin1,*(), QU Hao1, ZHOU Rui-Lian2, LI Jin1, PAN Cheng-Chen1, WANG Jin2   

  1. 1Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
    2School of Life Science, Ludong University, Yantai 264025, China
  • Received:2013-01-29 Accepted:2013-06-28 Online:2013-01-29 Published:2013-09-02
  • Contact: ZHAO Ha-Lin

Abstract:

Aims Our objectives were to determine effects of sand burial on growth and physiological response in psammophytes and to compare differences in abilities and mechanisms of different psammophytes to resist sand burial. We examined changes in survival rate, plant height, osmotic regulation substances contents, protective enzymes activity and membrane permeability of Agriophyllum squarrosumand Artemisia halodendronwith different sand burial depths during 2010 in the Horqin Sand Land of Inner Mongolia.
Methods There were ten sand burial treatments: buried to 0% (CK, no burial) and 25% (A), 50% (B), 75% (C) and 100% (D) of seedling height and 2, 4, 6, 8 and 10 cm above seedlings. Every treatment consisted of four replicates. Stress physiology properties were measured 10-12 days after sand burial, and plant height and survival rate were measured in late August.
Important findings With increased sand burial depth, both survival rate and plant height of Agriophyllum squarrosumand Artemisia halodendron decreased significantly, with a greater decrease in Artemisia halodendron. The maximum depth to resist sand burial exceeded 10 and 8 cm of seedling height for Agriophyllum squarrosumand Artemisia halodendron, respectively. The two psammophytes showed no water stress under sand burial stress. Decreased photosynthetic area and increased difficulties to emerge from the soil were the main factors that inhibited the survival and growth of the psammophyte seedlings. With increased depth of sand burial, malonaldehyde content increased significantly for Agriophyllum squarrosumand decreased significantly for Artemisia halodendron. The increased magnitude of membrane permeability was significantly lower in Artemisia halodendron. Injury of the cell membrane was the main physiological mechanism to decrease survival rate and inhibit growth in the psammophyte seedlings under sand-burial stress. Also, lighter membrane damage was the main physiological mechanism that gaveAgriophyllum squarrosum stronger resistance to sand burial. Although both species reduce plant cell membrane damage and degree of cytoplasm leakage by increasing peroxidase activity and proline content under sand burial stress, superoxide dismutase also showed an important coordinating role for Agriophyllum squarrosumthat makes its enzymatic system more effective in the protection of cell membrane from stress injury.

Key words: Agriophyllum squarrosum, Artemisia halodendron, growth inhibition, physiological response, sand burial stress