米槁对水分胁迫的生理响应

为探讨药用植物米槁对干旱胁迫的适应性,以米槁幼苗为研究材料,采用室内人工控水的方法,经预实验设3个水分梯度:CK(土壤相对含水量(80±5)%)、MD(土壤相对含水量(60±5)%)、SD(土壤相对含水量(35±5)%),研究了米槁幼苗对水分胁迫的生理响应机制.结果表明:同一实验期内随着干旱胁迫的加剧,RWC逐渐降低,电导率、MDA含量、渗透物质含量及抗氧化酶活性均增加.而同一水分处理下,随着干旱胁迫时间的延长,叶片相对含水量呈先大幅下降后小幅回升趋势;渗透物质、电导率、MDA含量和抗氧化系统都呈逐渐升高趋势.并且干旱胁迫越剧烈,米槁幼苗叶片RWC越小,电导率、MDA、渗透物质含量及抗氧化酶活性越大,机体抵抗干旱反应越强.但总体而言,米槁幼苗表现出较强抗旱性,对水分条件的适应范围较广.

Physiological response of Cinnamomum migao to water stress

In order to study the adaptability of Cinnamomum migao,a kind of medicinal plant,to drought stress,the indoor artificial water control method was used and the seedlings were treated as the research materials in this study.After pre-experiment,there were three water gradients:control group or mild drought group,CK/LD,whose relative soil water content was (80±5)%,moderate drought group,MD,whose relative soil water content was (60 ± 5)%,and severe drought group,SD,whose relative soil water content was (3 5 ± 5)%,to study the physiological response mechanism of Cinnamomum migao seedling in different water stress.The results showed that with the drought stress increasing,the relative water content of leaves decreased gradually,but the contents of osmotic substances,conductivity,MDA content and antioxidant enzyme activity were increasing gradually in the same experimental period.However,under the same water treatment,with the prolongation of drought stress time,the relative water content of leaves was decreasing at first and then increasing slightly.The contents of osmotic substances, conductivity,MDA and antioxidant system were increasing gradually.So,the drought stress is stronger,the RWC is smaller,the electrical conductivity,content of osmotic substance and MDA is higher,and the antioxidant enzyme activity is stronger,so the plants'resistance to drought is stronger.Overall,Cinnamomum migao seedlings showed strong drought resistance and wide adaptability to water conditions.