It is widely reported that global climate change has affected on the growth and distribution of plants. In order to investigate the response of different photosynthetic functional plants to drought stress, C3 plants (Leymus chinensis) and C4 plants (Chloris virgata) are chosen from Hunshandake Sandland to experience drought stresses treatments. One treatment was that the plants were drought naturally for 10 days after a saturant watering; the second treatment was that the plants were drought naturally for 10 days with accepting dew at each night after a saturant watering. Then the hydrological characteristics i.e. leaf water potential at dawn, the specific leaf area, stoma density, nitrogen content, and biomass were compared. And then different strategies in response to drought stresses were discussed. Drought stresses significantly decrease the leaf water potential at dawn (ψdawn) of Chloris virgata, while dew does not affect on the value of ψdawn of Chloris virgata. Drought stresses significantly lower ψdawn of Leymus chinensis at the tenth day after the drought period. Dew significantly affects the ψdawn of Leymus chinensis. Drought stresses significantly reduce Specific Leaf Area (SLA) and stomatal density; however, both of them are recovered to the normal level after re-watering. Nitrogen concentrations of Leymus chinensis are significantly increased under drought stresses; meanwhile there are no significant changes for Chloris virgata. Ratio of root and crown is improved for Leymus chinensis under drought stresses,and there is no differences for Chloris virgata. But the drought significantly improves the ratio of fruits and crown for Chloris virgata. The result indicates that more biomass is allocated into the roots for Leymus chinensis under drought stresses. This pattern is benefit for water absorption and improves resistance to the drought. By contrary, more biomass is input to produce seeds for Chloris virgata, which is helpful to expand its population. The results indicate that different strategies for two species are applied to in response to the drought stresses, and C3 species L. chinensis displays the higher ability to resist drought than that of C4 species C. virgata.
LIU Meizhen;ZHANG Haimin;YANG Shan;DU Jiancai;GUO Cuiyan;JIANG Gaoming
. Response Strategies of C3 and C4 Plants to Drought Stress in Hunshandake Sandland[J]. Science & Technology Review, 2011
, 29(25)
: 48
-53
.
DOI: 10.3981/j.issn.1000-7857.2011.25.007