水分胁迫对蔓生紫薇和亮叶忍冬生长及生理特性的影响

 采用盆栽试验法, 研究水分胁迫对蔓生紫薇(Lagerstroemia indica‘Summer and summer’) 和亮叶忍冬(Lonicera nitida‘Maigrun’) 两种木本地被植物生长及生理特性的影响。结果表明: 水分胁迫下,两种植物的生长受到明显抑制, 蔓生紫薇受抑制程度高于亮叶忍冬, 其相对生长量远小于亮叶忍冬。水分胁迫使两种植物净光合速率、蒸腾速率、气孔导度下降, 胞间CO₂浓度则前期下降后期上升, 且表现为蔓生紫薇各生理指标的变化幅度大于亮叶忍冬。综合评价两种植物的抗旱性为: 亮叶忍冬> 蔓生紫薇。

Effect of Water Stress on Growth and Physiological Characteristics of Lagerstroemia indica ‘Summer and summer’ and Lonicera nitida ‘Maigrun’

Growth and physiological characteristics of two ground cover plants, Lagerstroemia indica‘Summer and summer’and Lonicera nitida‘Maigrun’which grown in pots, were investigated under the treatment of water stress. Criteria to evaluate drought resistance, including growth increments, photosynthetic rate ( Pn) , transp iration rate ( Tr) , stomatal conductance ( Gs) and intercellular CO₂ concentration (Ci) were determined in the experiment. The results showed that with the water stress the growth of both varietieswas inhabited obviously, the relative growth rate of‘Summer and summer’was lower than that of‘Maigrun’, indicating the growth of the former was more retarded by water stress. The photosynthetic rate ( Pn) , transpiration rate (Tr) and stomatal conductance (Gs) in the treated plants appeared to decrease while intercellular CO₂ concentration (Ci) ranged from the decline at beginning to the increase at the later period of the experiment, each index variation degree of‘Summer and summer’was greater than that of‘Maigrun’. According to multiple analysis the drought resistance order for the two varieties was‘Maigrun’ > ‘Summer and summer’.