边坡先锋植物多花木兰的抗旱性

目的]揭示多花木兰对土壤干旱胁迫的响应。方法]采用盆栽控水法模拟干旱条件,测定多花木兰光合、生理指标。结果]多花木兰的净光合速率在轻度干旱胁迫下变化不明显,而在中度和重度干旱胁迫下显著降低;干旱胁迫使气孔导度、蒸腾速率、胞间CO_2浓度整体呈现下降趋势,在重度干旱胁迫下净光合速率、气孔导度、蒸腾速率、胞间CO_2浓度分别较对照组下降了61.04%、86.27%、87.77%和42.63%;多花木兰叶片丙二醛含量在轻度干旱胁迫下增加不显著,在中度和重度干旱胁迫下显著增加,重度干旱胁迫下丙二醛含量是对照组的1.63倍;多花木兰脯氨酸和可溶性糖含量随干旱胁迫的加剧均呈显著增加趋势,在重度干旱胁迫下其脯氨酸和可溶性糖含量分别是对照组的8.06和3.16倍。结论]多花木兰耐旱性较强,适宜于偏干旱环境生长,可作为水电边坡植被修复物种。

Drought Resistance of Slope Pioneer Plant Magnolia multiflora

Objective] The aim was to reveal response of M.multiflora to soil drought stress.Method] Using pot water controlling method to simulate drought conditions,photosynthesis,physiological index of M.multiflora were determined.Result] Results showed that there was no sig-nificant influence on Pn of M.multiflora under mild drought stress.There was a significant decrease in moderate and severe drought stress,and the drought stress led to Gs,Tr,Ci significantly decreased,the Pn,Gs,Tr,Ci decreased 61.04%,86.27%,87.77% and 42.63% compared with the control group.With the aggravation of drought stress,the MDA in M.multiflora leaves was not significantly increased in mild drought, the Pro and soluble sugar of M.ultiflora content increased with the drought stress,the content of Pro and soluble sugar were 8.06 times and 3.16 times than the control groups under severe drought.Conclusion] M.multiflora has a strong draught tolerance,and is suitable for growing in the conditions of mild drought habitats,and M.multiflora can be considered as the key plant in terms of vegetation restoration in hydropower engi-neering slope.