EDTA对重金属胁迫下匍匐翦股颖种子萌发的影响

Effects of EDTA on seed germination of creeping bentgrass under heavy metal stress

摘要:

【目的】研究外源 EDTA 对重金属胁迫下匍匐翦股颖（Agrostis stolonifera）种子萌发的影响。 【方法】以匍匐翦股颖品种潘威为试验材料，对不同浓度 Cu、Cd、Pb 胁迫下的匍匐剪股颖进行 EDTA 处理，并测定匍匐翦股颖种子发芽率、发芽势、发芽指数、幼苗叶片及根系相关指标。【结果】匍匐翦股颖对 Pb 的耐受能力最强，Cu 次之，Cd 最差。施加 3 mmol/L EDTA 对中、重度重金属胁迫下匍匐翦股颖的发芽指标、叶片指标和根系指标均较优，其中，中度 Cu、轻度 Cd、中度 Pb胁迫下施用 3m m o l / L EDTA 的匍匐翦股颖种子的发芽率分别较对照增加了 16. 67%、3. 36%、8. 72%，叶片长度分别增加了 30. 99%、30. 60%、1. 63%，根系长度分别增加了 35. 93%、0. 37%、29. 80%。【结论】通过隶属函数法对各处理进行综合排序，发现施用 3 mmol/L EDTA 匍匐翦股颖对重金属胁迫的缓解效果最优，对 3 种重金属的缓解效果排序为 Pb＞Cu＞Cd。

Abstract:

【Objective】 In order to study the effect of exogenous EDTA on seed germination of creeping bentgrass （Agrostis stolonifera L.） under heavy metal stress.【Method】 The creeping bentgrass ' Pennway ' variety was used as the test material，and the creeping bentgrass under different concentrations of Cu，Cd and Pb stress was treated with EDTA，and the seed germination rate，germination potential，germination index，seedling leaf and root related indexes of creeping bentgrass were determined.【Result】 The results showed that creeping bentgrass had the strongest tolerance to Pb，followed by Cu and Cd. The application of 3 mmol/L EDTA had better germination index， leaf index and root index of creeping bentgrass under moderate and severe heavy metal stress. Among them，the germination rate of creeping bentgrass seeds treated with 3 mmol/L EDTA under moderate Cu，mild Cd and moderate Pb stress increased by 16. 67%，3. 36% and 8. 72%，respectively，compared with the controls. The leaf length increased by 30. 99%，30. 60% and 1. 63%，respectively，and the root length increased by 35. 93%，0. 37% and 29. 80%，respectively.【Conclusion】 Through the comprehensive ranking of each treatment by the membership function method，it was found that the application of 3 mmol/L EDTA had the best mitigation effect on heavy metal stress，and the mitigation effect on the three heavy metals was ranked as Pb ＞ Cu ＞ Cd.