毛叶地瓜苗幼苗对干旱胁迫的响应

为评估毛叶地瓜苗适应干旱的能力，以毛叶地瓜苗幼苗为材料，采用盆栽试验设计，设置土壤相对含水量20%，40%，60%，80% 4个干旱胁迫处理，研究了不同强度干旱胁迫下毛叶地瓜苗幼苗的生长特性及生理生化反应。结果表明：（1）随着干旱胁迫的增强，毛叶地瓜苗幼苗株高及叶面积生长量降低；（2）丙二醛（MDA）与可溶性糖含量随着干旱胁迫强度的增强呈增加趋势；（3）光合色素（Chl a，Chl b，Car）含量在干旱胁迫梯度下的反应均表现为多项式变化规律，即在中度干旱下的含量显著升高，而重度胁迫下降低。综合分析表明，40%左右的土壤含水量是毛叶地瓜苗幼苗叶片生理生化代谢受到伤害的干旱强度阈值。

Responsed of Lycopus lucidus Turcz.var. hirtus Regel. to drought stress

To assess the adaptation of Lycopus lucidus Turcz.var. hirtus Regel. under drought stress，seedlings of Lycopus lucidus Turcz.var. hirtus Regel were used as materials to study the growth， physiological and biochemica characters under conditions of four artificial controlled drought treatments （20%， 40%， 60% and 80%）. The results showed that the growth of height and leaf area declined with the increase of drought stress; the MDA contents increased under drought stress; Chl a， Chl b and carotenoid contents were increased under the moderate drought while decreased under the severe stress. For the Lycopus lucidus Turcz.var. hirtus Regel. seedlings， the 40% soil water condition was the threshold at which the negative effect of drought on the physiological and biochemical activities of the leaves was observed.