不同光环境下金边百里香的形态和生理可塑性

本研究采用1年龄金边百里香(Thymus mongolicus)幼苗为试验材料,以自然光照作为对照处理,设置25%、50%和75%遮光处理梯度,分别于处理0、7、14、24、44d时测定其叶部、根部的生理和形态指标,以期为芳香地被植物的选育及推广提供基础理论依据。结果表明,1)在处理14d时干物质分配发生了改变,通过增加叶重比、降低根重比来平衡不同光环境下植株体内的养分累积。2)50%的光照处理显著促进了叶部超氧化物歧化酶(SOD)的活性,增加了根部渗透调节物质可溶性蛋白的含量,抑制了植株内丙二醛(MDA)的积累,表现出较强的生理可塑性。3)金边百里香在50%的光环境较其它光环境处理下的形态和生理可塑性强,且不同光环境下叶部的生理可塑性较根部显著。

Morphological and physiological plasticity of Thymus mongolicus under different light conditions

One-year-old Thymus mongolicus seedlings were used as the test material.They were grown under either natural light (control,CK),or 25,50 and 75％ shading;physiological and morphological indexes of leaves and roots were measured at 0,7,14,24,and 44 d.The study aimed to identify tissue plasticity in T.mongolicus under different illumination conditions so as to provide a theoretical basis for the selection and promotion of aromatic ground cover plants.The results showed that 1) changes in the distribution of dry matter content at 14 d was due to an increase in leaf weight ratio and a reduction in root weight ratio under different light conditions.2) The 50％ light treatment significantly promoted the activity of leaf SOD,increased the content of soluble protein in the root osmotic adjustment substances,inhibited the accumulation of malondialdehyde,and showed strong physiological plasticity.3) T.mongolicus showed greater morphological and physiological plasticity under 50％ light,and significantly different physiological plasticity in leaves and roots in response to environmental changes.