声明
摘要
Abstract
1 Introduction
1.1 Background study
1.2 Impact of Pesticide usage on Soil Microorganism
1.3 Atrazine Application History
1.4 Gains of Nutrients to Soil
1.5 Role of soil Microorganisms in Soil
1.6 Internal Transformations of Nutrients in Soil
1.7 Sulfur(S)
1.8 Gains of Sulfur to Soil
1.9 Microorganisms involved in soil sulfur cycle
1.10 Aims and Objectives of the Study
2 Materials and methods
2.1 Materials and Methods in Experiment 1
2.1.1 Plant materials and atrazine stress treatment
2.1.2 Measurement of the Ascorbate and Glutathione contents
2.1.3 Determination of Glutathione S-transferase and Glutathione Reductase
2.1.4 Determination of Hydrogen peroxide and superoxide radicals
2.1.5 Statistical analysis
2.2 Materials and Methods in Experiment 2
2.2.1 Plant materials and growth conditions
2.2.2 ROS detection by confocal laser scanning fluorescence microscopy(CLSM)
2.2.3 Enzyme extraction and antioxidant enzymes assays(APX,CAT and POD)
2.2.4 Reactive oxygen species quantification and Chlorophyll contents analysis
3 Result analysis
3.1 Soil Total DNA Extraction
3.2 PCR Products of aprA gene with soil total DNA as template
3.3 PCR Product Purification
3.4 Cloning and sequencing
3.5 Gene Bank Accession number and Identification of Closet Sequence
3.6 Similarity Analysis
3.7 Phylogenetic Analysis Based on aprA gene Sequence
3.8 Variability of Soil Microbial Biomass and DNA in Summer Season
3.9 Variability of Soil Microbial Biomass and DNA in Spring Season
3.10 Impact of Seasonal Variations and Fertilizers on Soil MB,DNA and ODR
3.11 Correlation between Spring and Summer Variations on Selected Parameters
4 Discussion
4.1 Influence of Atrazine on Soil Microbial Communities
4.2 Selection of Soil Sulfur 16S rRNA Genes
4.3 Evaluation of Microbial Diversity by using aprA Gene
4.4 Sulfate Reducing and Oxidizing Prokaryotic Diversity by Cloning of aprA Gene
4.5 Soil biological Indicators
4.6 Soil Microbial Biomass
4.6.1 Impact of Organic Fertilizers on soil Microbial Biomass
4.6.2 Impact of Inorganic fertilizers on soil Microbial Biomass
4.6.3 Impact of Seasonal Variations on soil Microbial Biomass
4.7 Relationship Between Soil Microbial biomass and soil DNA
5 Conclusion
Acknowledgement
References
Research Publication in Period of Ph.D Education