北方6种园林绿化灌木水分参数对干旱胁迫的响应

以红瑞木(Cornus alba)、红王子锦带(Weigela floridacv.Red prince)、麦李(Prunus glandulosa)、辽东水蜡(Ligustrum obtusifolium)、杞柳(Salixintegra)、忍冬(Lonicera maackii)6种绿化灌木幼苗为材料,采用盆栽控水法研究6种苗木在干旱胁迫下的水分状况。设置4种土壤水分条件,土壤含水量分别设为55%(A)、45%(B)、35%(C)和25%(D)。应用PV技术测定不同苗木的束缚水含量(Va)、饱和时的最大渗透势(Ψ1π00)、膨压为0时的渗透势(Ψ0π)、相对含水量(CR0W)、相对渗透水含量(C0ROW)、组织细胞体积最大弹性模量(εmax)等水分参数,并用模糊隶属函数值法对6种苗木在水分胁迫条件下的渗透调节和维持膨压的能力进行综合评定。结果表明:6个树种的Ψπ100、Ψπ0、CR0W、CR0OW、Va和εmax值均不同,抗旱性也存在一定的差异,抗旱能力大小依次为红瑞木红王子锦带麦李辽东水蜡杞柳忍冬。它们通过不同的方式来适应干旱环境,其抗旱能力的大小是相对而言的。

Responses of Moisture Parameters of Six Landscape Shrub Species in Northern China to Drought Stress

Six landscape shrub species, including Cornus alba, Weigela florida cv. Red prince, Prunus glandulosa, Ligustrum obtusifolium, Salix integra, Lonicera maackii were selected as materials to investigate water regime of the potted seedlings under drought stress. Four soil moisture contents were set, namely 55%, 45%, 35%, and 25%. Moisture parameters, involving bound water content (V_a), osmotic potential at full turgor (Ψ_π~(100)), osmotic potential at zero turgor (Ψ_π~0), relative water content (C_(RW)~0), relative osmotic water content (C_(ROW)~0), and the maximum cellular elastic modulus were measured by using PV technology. In addition, the osmotic adjustment and the maintenance of turgor pressure in the six species under water stress were evaluated by subordinate function value analysis. Results show that the six species have significant differences in Ψ_π~(100), Ψ_π~0, C_(RW)~0, C_(ROW)~0, V_a and ε_(max), indicating a difference in drought resistance between different species. The drought resistance of C. alba is the highest, followed by W. florida cv. Red prince, P. glandulosa, L. obtusifolium, S. integra, and L. maackii from high to low. These species have different adaptive mechanisms to drought environment, and the drought resistances of different species are relative.