MODE OF ACTION OF GROWTH ENHANCES AND CHELATING COMPOUNDS ON THE UPTAKE OF CD AN

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 利用植物修复环境中的重金属是一种新的技术，通常被称为植物修复。许多植物已经显示出从受污染的生长介质中吸收重金属的能力，包括铅和镉。然而，添加络合剂如EDTA已被证明增加了镉和铅在许多不同植物物种中的吸收和转运。我们最近一直在研究赤霉酸、吲哚-3-乙酸、激动素、2，4-二氯苯氧酸和谷胱甘肽等生长促进剂与EDTA的混合物的使用。我们观察到，EDTA和IAA的特定摩尔组合使紫花苜蓿对铅的吸收比仅用铅处理的紫花苜蓿叶片增加了约2800%。此外，与单独使用EDTA相比，等摩尔浓度的吲哚-3-乙酸和EDTA使紫花苜蓿叶片对铅的吸收增加了600%。然而，当吲哚-3-乙酸-EDTA组合使用时，紫花苜蓿根和茎对铅的吸收减少。这些结果在生产可行的植物修复系统方面有很大的希望。我们计划使用XAS来了解生长促进剂/促进剂在活体植物中对铅和镉的吸收和协调的化学和随后的作用模式。XAS研究将为我们提供对这一复杂的生化过程的化学理解，降低金属的毒性，同时增加金属在植物中的转移。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The remediation of heavy metals from the environment using plants is a novel technology commonly termed phytoremediation. Many plants have shown the ability of uptake heavy metals, including lead and cadmium, from contaminated growth media. However, the addition of chelating agents such as EDTA has been shown to increase the uptake and translocation of both cadmium and lead in many different plant species. We have recently been investigating the use of growth promoters such as gibberlic acid, indolic-3-acetic acid, kinetine, 2,4-dichlorophenoxy acid, and glutathione, with mixtures of EDTA. We have observed that specific molar combinations of EDTA and IAA increase the uptake of lead in alfalfa plants by approximately 2800% over treatments with lead alone in the leaves of the plants. In addition, the use of equal molar concentrations of indole-3-acetic acid and EDTA increased the uptake of lead by 600% over the use of EDTA alone in the leaves of alfalfa plants. However, in the roots and stems of the alfalfa plants the uptake of lead was reduced when combinations of indole-3-acetic acid-EDTA were used. These results have much promise in producing a viable phytoremediation system. We plan to use XAS to understand the chemistry and subsequently, the mode of action that growth promoters/ enhancers have on the uptake and coordination of both lead and cadmium in live plants. XAS studies will provide us with a chemical understanding of this complex biochemical process of reducing the toxicity of the metals and at the same time increasing the translocation of metals through the plant.