The increase of metals pollution in soil is a worldwide problem that effects the health of humans and environment. The use of green technology such as phytoremediation is one the environmental friendly technique, in which plants and other microbes are used to reduce the level of metals contaminants in soil and lower its uptake towards plants tissues.
Studies reported a number of cereal crops such as wheat and medicinal plants like alfalfa accumulate heavy metals in their tissues at higher concentrations. In the present study, we investigated the effect of arbuscular mycorrhizal fungi (AMF) on wheat and alfalfa plants with the increase of zinc (Zn) and cadmium (Cd) concentrations in soil. After eight weeks of pot experiment, roots colonization, shoot and root biomass, growth, heavy metals contents and other biochemical parameters were assessed.
The results indicated mycorrhizal inoculated (M) plants performed better at moderate Zn and Cd concentrations. In addition, higher phosphorus contents were observed in M treated plants as compared to NM plants. Results indicated that AMF inoculum exhibit different tolerance strategies to reduce metals toxicity in host plants. The effective mycorrhizal symbiosis was observed with wheat and alfalfa plants and can be useful for phytostabilization of metals contaminated soils which can play a vital role in increase of plants productivity and safety.
Table of Contents
Role of arbuscular mycorrhizal fungi in phytoremediation of heavy metals and effects on growth and biochemical activities of wheat (Triticum aestivum L.) plants in Zn contaminated soils
1. Introduction
2. Experimental methodology
2.1 Experimental design
2.2 Soil preparation
2.3 Use of AMF Glomus species
2.4 Disinfection and germination of wheat seeds
2.5 Seeds sowing and harvesting of plants
2.6 Mycorrhizal colonization of roots
2.7 Biomass of plants
2.8 Plant growth
2.9 Metal contents in plants
2.10 Biochemical contents of plants
2.11 Antioxidant enzymes activity in plants
2.12 Quality Control (QC/QA) analysis
2.13 Statistical Analysis
3. Results
3.1 Roots mycorrhizal colonization
3.2 Plant Growth and Biomass
3.3 Macro and micro-nutrients uptake
3.4 Phosphorus (P) content in plant tissues
3.5 Zinc uptake in plants tissues
3.6 Biochemical contents in plant tissues
3.7 Antioxidant enzyme activities in plants
4. Discussion
Effects of arbuscular mycorrhizal fungi on wheat growth, physiology, nutrition and cadmium uptake under increasing cadmium stress
1. Introduction
2. Materials and Methods
2.1 Plant materials
2.2 Preparation of soil
2.3 Fungal inoculum
2.4 Pot experiment and growth conditions
2.5 Plant measurements and analysis
3. Results
3.1 Plant biomass and Mycorrhizal colonization
3.2 Effect on plant growth
3.3 Plant Phosphorus (P) uptake
3.4 Cd uptake in wheat plants
3.5 Plant nutrient contents
3.6 Plant biochemical Analyses
3.7 Antioxidant enzyme activities
4. Discussion
Effects of arbuscular mycorrhiza fungi on metals uptake, physiological and biochemical response of Medicago Sativa l. with increasing Zn and Cd concentrations in soil
1. Introduction
2. Materials and Methods
2.1 Experimental design and soil preparation
2.2 Inoculum of Glomus species:
2.3 Sterilization of Alfalfa seeds:
2.4 Evaluation of mycorrhizal colonization:
2.5 Plant growth:
2.6 Plant biomass:
2.7 Analytical determinations
2.8 Quality Control Analysis:
2.9 Statistical analysis:
3. RESULTS
3.1 Mycorrhizal colonization of roots
3.2 Plant Growth and Biomass
3.3 Plant Nutrient contents
3.4 Plant Phosphorus (P) uptake
3.5 Zinc and Cd uptake in Alfalfa plants
3.6 Effects of metals concentrations on plants biochemical activities
3.7 Effects of metals on plants antioxidant enzyme activities
4. Discussion
4.1. Effect of AMF inoculation on alfalfa growth, biomass and colonization under Zn and Cd toxicity
4.2 Effect of AMF on Zn and Cd uptake in Alfalfa plants
4.3 Effects of AMF on nutrients uptake and biochemical contents under Zinc and Cd toxicity
Objectives and Research Themes
This work investigates the role of arbuscular mycorrhizal fungi (AMF) in the phytoremediation of heavy metals (Zinc and Cadmium) in soil and their subsequent effects on the growth, physiological parameters, and biochemical activities of wheat (Triticum aestivum) and alfalfa (Medicago Sativa). The research addresses the following question: To what extent does mycorrhizal inoculation alleviate heavy metal toxicity and improve plant productivity and nutrient uptake in contaminated soils?
- Impact of AMF on heavy metal accumulation and plant tolerance.
- Physiological response of crops under increasing metal stress.
- Biochemical alterations and antioxidant enzyme activities in host plants.
- Role of mycorrhizal symbiosis in nutrient uptake (especially Phosphorus) in contaminated environments.
- Evaluation of phytostabilization as an environmental friendly green technology.
Excerpt from the Book
1 Introduction
Soil contamination with heavy metals is the most challenging problem nowadays that is the consequence of increasing emissions from both natural and anthropogenic sources. The increase level of metals threatens the quality of food and management of sustainable environment (Thounaojam et al., 2012). Among the metals, Zn is one of the essential micronutrients required by plants in adequate quantities and play an important role in numerous structural and metabolic processes of plants. Excessive concentrations of Zn in soil increase the plants toxicity and consequently decrease the plant growth, yield and level of reactive oxygen species (ROS) (Sgherri et al., 2002).
Nowadays, the useful function of mycorrhiza in decrease of phytotoxicity has been generally known. The mechanism of phytoremediation can be increased by using arbuscular mycorrhizal fungi (AMF) in soil. AMF are symbionts colonized with plant roots found in many plant species and contaminated soils with heavy metals. AMF immobilize Zn in plant roots which decrease the harmful effects of metals on plants physiological and metabolic functions. Several studies indicated that plants grow in the presence of AMF have developed a variety of useful mechanisms that reduce the metals uptake in plants, increase the nutrient contents and form an efficient symbiotic relationship by inducing several mycorrhizal structures inside plant roots like arbuscules or vesicles (Gohre et al., 2006).
Despite the importance of wheat crop in agriculture, no detailed information is available about biochemical alterations induced in the crop due to excessive metals concentrations (Mallick et al., 2011). In addition, little information is available with respect to association of mycorrhiza with wheat plants under toxic Zn concentrations, and the influence of mycorrhization on physiological and biochemical functions of wheat. The purpose of the study was to investigate the effects of mycorrhizal inoculation on growth, nutrients and biochemical contents of wheat plants grown in low (100 mgkg-1), moderate (300 mgkg-1) and high (900 mgkg-1) Zn concentrations. The hypothesis of the study was that use of AMF inoculum in metals contaminated soils immobilize the metals contents in plants roots, increase growth, nutrients contents and other biochemical activities in plant tissues enhance the quality and food productivity.
Summary of Chapters
1 Introduction: Provides an overview of heavy metal contamination as a worldwide problem and establishes the theoretical basis for using arbuscular mycorrhizal fungi as a green technology for phytoremediation.
2 Experimental methodology: Details the controlled pot experiments, including soil preparation, inoculation with Glomus species, seed sterilization, and the assessment of physiological and biochemical parameters.
3 Results: Reports on the impact of AMF inoculation on root colonization, plant biomass, nutrient uptake, and antioxidant enzyme activity under various heavy metal concentrations.
4 Discussion: Interprets the findings regarding how mycorrhizal symbiosis mitigates metal toxicity, enhances plant nutrient uptake, and protects metabolic functions in stressed plants.
Keywords
Arbuscular mycorrhizal fungi, Phytoremediation, Heavy metals, Zinc, Cadmium, Wheat, Medicago Sativa, Soil contamination, Oxidative stress, Antioxidant enzymes, Plant biomass, Nutrient uptake, Symbiosis, Sustainable agriculture, Metal toxicity.
Frequently Asked Questions
What is the primary objective of this research?
The primary objective is to investigate the potential of arbuscular mycorrhizal fungi (AMF) to mitigate heavy metal toxicity (specifically Zinc and Cadmium) in crops like wheat and alfalfa and to understand how this symbiosis improves plant growth and nutrient uptake in contaminated soils.
What central themes are explored in this work?
The work explores metal stress in plants, the defensive mechanisms induced by AMF, the role of antioxidant enzymes, and the efficiency of phytoremediation as a sustainable solution for food safety and agricultural productivity.
What research methodology is applied?
The study employs controlled pot experiments where plants are grown under varying levels of heavy metal stress. Data on growth, biomass, nutrient contents, and biochemical markers are collected and analyzed using statistical methods like two-way analysis of variance (ANOVA) and the Tukey test.
What constitutes the main body of the work?
The main body focuses on empirical results derived from experiments on wheat and alfalfa, detailing how mycorrhizal colonization affects plant physiology, nutrient accumulation, and the defense mechanisms against ROS production under metal stress.
What is the significance of the findings?
The findings demonstrate that AMF can effectively alleviate heavy metal toxicity, protect plant health, and enhance crop yield, supporting its application as a promising tool for managing contaminated agricultural lands.
How is the research characterized?
The research is characterized by its focus on environmental toxicology, plant nutrition, and the symbiotic interaction between fungi and plants, framed within the broader context of ecological sustainability.
How does AMF assist in the retention of heavy metals?
The research suggests that AMF can immobilize metals like Zn and Cd within fungal hyphae and roots, preventing their translocation to the shoot and thereby reducing toxicity in the plant tissues.
What role do antioxidant enzymes play in the findings?
Antioxidant enzymes such as SOD, CAT, and APX are shown to play a vital role in the defensive mechanisms of mycorrhizal plants, helping to scavenge reactive oxygen species (ROS) produced by metal-induced oxidative stress.
- Arbeit zitieren
- Sadia Kanwal (Autor:in), 2013, Potential Role of Arbuscular mycorrhizal fungi in Phytoremediation, München, GRIN Verlag, https://www.grin.com/document/323551
