Effect of Hexavalent Chromium Cr(VI) on Phytoremediation Potential and Physiological Response of Hybrid Napier Grass with and without EDTA Application

目录

声明

1Introduction

2Literature review

2.1 Physical properties and toxicity of chromium (Cr)

2.2 Cr chemical forms and features

2.3 Cr sources and the environmental contamination

2.3.1 Natural sources and geogenic release

2.3.2 Anthropogenic sources

2.4 Cr toxicity in plants

2.4.1 Cr uptake, transfer and accumulation in plants

2.4.2 Effects of Cr on plant growth and development

2.4.3 Cr effects on biochemical and minerals in plants

2.4.4 Effects of Cr on photosynthesis in plants

2.4.5 Effects of Cr on oxidative stress in plants

2.5 Remediation strategies and phytoremediation of soil Cr

2.5.1 Physical methods

2.5.2 Chemical methods

2.5.3 Thermal methods (Vitrification)

2.5.4 Electrokinetics

2.5.5 Bioremediation

2.6 Types of phytoremediation technologies

2.6.1 Phytoextraction

2.6.2 Phytotransformation

2.6.3 Phytostimulation

2.6.4 Phytostabilization

2.6.5 Phytovolatilisation

2.6.6 Rhizofiltration

2.6.7 Pump and tree

2.6.8 Hydraulic control

2.7 Overview of the phytoremediation of Cr

2.8 Plants potential for the phytoextraction of Cr

2.9 Role of EDTA as chelating agent in Cr phytoremediation

2.10 Fourier transform infrared spectroscopy (FTIR)

2.11.1 Introduction

2.11.2 Development of hybrid Napier grass

2.12 Objectives and implications of the present study

2.12.1 Objectives

3Materials and methods

3.1 Collection of seeds and stock solution preparation

3.2 Soil collection, preparation and seedling growth

3.3 Experimental design

3.4 Growth measurements

3.5 Chromium analysis

3.6.1 Cr concentration and accumulation in plant

3.6.2 Transfer factor (TF) and bioaccumulation factor (BAF)

3.7 Determination of chlorophyll content

3.8 Chlorophyll a fluorescence measurement

3.9 Determination of N and S concentrations

3.10 Tolerance index (TI)

3.11 Measurement of lipid peroxidation and antioxidant enzymes

3.12 Fourier-transform infrared spectroscopy (FTIR)

3.13 Statistical analysis

4Results

4.1 Growth characteristics of hybrid Napier grass

4.2 Phytoremediation potential of the plant

4.2.1 Cr concentration and accumulation in plant

4.2.2 Transfer factor (TF) and bioaccumulation factor (BAF)

4.3 Chlorophyll content

4.4 Photosynthetic efficiency

4.5 Basic elemental (N and S) status in hybrid Napier grass

4.6 Tolerance index (TI)

4.7 Oxidative stress

4.8.1 FTIR analysis of root

4.8.2 FTIR analysis of shoot

5Discussion

5.1 Plant growth

5.2 Cr uptake and accumulation

5.3 Chlorophyll and photosynthetic efficiency

5.4 Elemental (N and S) status

5.5 Tolerance and oxidative stress

5.6 FTIR analysis of root and shoot

5.7 Effects of EDTA application

6Conclusion

致谢

DEDICATION

参考文献

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