中南林业科技大学学报2025，Vol.45Issue(9)：1-11,11.DOI:10.14067/j.cnki.1673-923x.2025.09.001
白花泡桐幼苗对铅胁迫的耐受机制与积累特性
The tolerance mechanism and accumulation characteristics of Paulownia fortunei seedlings under lead stress
摘要
Abstract
[Objective]To explore the tolerance mechanism and lead accumulation characteristics of Paulownia fortunei seedlings under lead stress,in-depth investigation of the intrinsic mechanism of Paulownia fortunei tolerance of heavy metals,so as to provide theoretical support and scientific basis for the development and utilization of heavy metal contaminated land.[Methods]60 days Paulownia fortunei seedlings were taken as experimental materials and five groups of Pb treatments were set up with different concentrations of Pb to simulate the Pb stress environment,and measured the growth indexes,root parameters,antioxidant enzyme activities,MDA content,photosynthetic gas parameters,chlorophyll,Pb accumulation,enrichment coefficient and transport coefficient of the seedlings.[Results]As lead mass concentration increased,biomass,root parameters,photosynthetic parameters,and chlorophyll content in Paulownia seedlings across all treatment groups decreased significantly(P＜0.05),while the limiting stomatal conductance(Ls)rose markedly;SOD and CAT activities weakened concurrently,whereas POD activity remained stable.MDA content increased significantly.At a mass concentration of 800 mg/L(P4),above-ground biomass,leaf area,plant height,stem diameter at ground level,and chlorophyll content increased.Lead content and the enrichment factor in Paulownia seedlings gradually increased,with heavy metal accumulation in plant parts following the pattern:roots＞leaves＞stems.The transport coefficient exhibited a zigzag decrease with increasing lead mass concentration.[Conclusion]Under Pb stress,the root uptake function of seedlings was weakened,resulting in growth restriction and significant reduction of several physiological indexes.However,under 800 mg/L(P4)treatment,the growth and physiology of P.vesiculosus seedlings were promoted to different degrees.The seedlings accumulated most of the Pb in the root system to reduce the level of membrane lipid peroxidation induced by heavy metal stress,and thus showed a certain degree of tolerance to the stress induced by different concentrations of Pb.关键词
白花泡桐/铅胁迫/生理响应/Pb积累量/转运系数Key words
Paulownia fortunei/Pb stress/physiological response/Pb accumulation/translocation coefficient分类
农业科技引用本文复制引用
朱秀红,马静雨,张龙冲,张梁迪,赵白雪,茹广欣..白花泡桐幼苗对铅胁迫的耐受机制与积累特性[J].中南林业科技大学学报,2025,45(9):1-11,11.基金项目
河南省级财政林业科技推广项目(30802824) （30802824）
国家林业和草原局经济发展专项(30803179). （30803179）
