采用苗期盆栽试验，对14份禾本科牧草种质材料进行不同浓度（0，10，50，100，200，300 mg／kg）铅（Pb）胁迫处理，通过对株高、分蘖数、地上／地下生物量、脯氨酸含量、抗氧化酶（SOD、POD、CAT）活性、地上部与根中 Pb2＋含量等指标的测定与分析，探究 Pb 胁迫对禾草生长生理以及 Pb2＋富集转运的影响。结果表明，随着 Pb 浓度的增加，14份材料的株高、分蘖数、地上生物量均呈先上升后下降的趋势，地下生物量则逐渐降低，通过综合评价，来自土耳其的长穗冰草 G5具有较强的耐 Pb 性。随着 Pb 浓度的增加，地上部与根中 Pb2＋含量逐渐升高，富集系数逐渐降低，转移系数逐渐降低（披碱草 G7与 G8除外），根中 Pb2＋含量显著高于地上部，为 Pb2＋的主要富集器官，披碱草地上部 Pb2＋含量高于其他材料，具有较强的 Pb 富集转运能力。7份材料的生理指标测定结果表明，随着 Pb 浓度的增加，7份材料的脯氨酸含量逐渐上升，CAT 活性逐渐下降，POD 和 SOD 活性则呈先上升后下降的趋势。%Fourteen gramineous forages were stressed by different lead treatments (0,10,50,100,200,300 mg/kg)at the seedling stage in pots.By measurement of plant height,tiller number,shoot and root biomass, antioxidant enzyme activities and shoot and root lead ion content,the effects of lead stress on growth,physiol-ogy,accumulation and transportation were analyzed.At low levels of lead exposure,plant height,tiller num-ber and shoot biomass were generally increased,then reduced gradually with increasing lead exposure.Agro-pyron elongatum G5 from Turkey was found to have a high lead tolerance.With increasing lead exposure,lead ion content in roots and shoots increased gradually,while the bio-concentration factor and transfer factor de-creased gradually except for Elymus dahuricus G7 and G8 .The content of lead ions in roots was significantly higher than that in shoots,from which we concluded that the root was the main organ by which Poaceous fora-ges accumulate lead ions.The content of lead ions in shoots of E .dahuricus G7 and G8 were higher than in oth-er germplasm,indicating a high capacity for lead accumulation and transportation.From physiological analysis of seven evaluated varieties,it was found that with increased lead exposure,proline content increased gradual-ly,and catalase (CAT)activity decreased gradually,while peroxidase (POD)and superoxide dismutase (SOD) were elevated at low levels of exposure,but decreased at higher levels of exposure.
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