草地学报2026，Vol.34Issue(5)：1691-1700,10.DOI:10.11733/j.issn.1007-0435.2026.05.012
Pb胁迫对紫花苜蓿种子萌发生理及幼苗抗氧化系统和Pb积累的影响
The Effects of Pb Stress on the Germination Physiology of Alfalfa Seeds,Antioxidant System of Seedlings,and Pb Enrichment Effect
摘要
Abstract
This study investigated the effects of Pb stress on the physiology of seed germination and the antioxi-dant system and Pb accumulation in seedlings of alfalfa(Medicago sativa).Six Pb stress concentrations were set to evaluate seed germination physiology,and three Pb stress concentrations were established to assess the activity of the antioxidant system and Pb content in seedlings.The results showed that:(1)Pb stress inhibited seed imbibition and germination,reduced the activities of amylase and protease,and decreased the levels of soluble sugars,reducing sugars,free proline,and free amino acids.(2)The suitable concentration for Pb during seed germination of alfalfa was≤1.84 mmol·L-1,with a half lethal concentration and a limit concentra-tion of 3.93 mmol·L-1 and 7.29 mmol·L-1,respectively.(3)Under 2.0 mmol·L-1 Pb stress,the antioxidant system activity in seedling leaves initially increased and then decreased.At 4.0 mmol·L-1 Pb stress,the anti-oxidant system collapsed,and oxidative damage intensified.(4)Under Pb stress,Pb content in seedlings sig-nificantly increased,with the highest levels in roots,followed by stems and leaves.Only a small amount of Pb translocated from underground to aboveground parts.This indicates that Pb stress inhibited seed germination,exacerbated oxidative damage in seedlings,led to the collapse of the antioxidant system,and caused substantial Pb accumulation in seedling roots.The study provides a theoretical basis for using alfalfa to remediate Pb-con-taminated soils.关键词
紫花苜蓿/Pb胁迫/萌发生理/抗氧化系统/富集效应Key words
Alfalfa/Pb Stress/Germination physiology/Antioxidant system/Enrichment effect分类
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李小娥..Pb胁迫对紫花苜蓿种子萌发生理及幼苗抗氧化系统和Pb积累的影响[J].草地学报,2026,34(5):1691-1700,10.基金项目
紫花苜蓿栽培技术推广示范资助 （）
