Dissertation > Excellent graduate degree dissertation topics show

Effect of Arbuscular Mycorrhizal Inoculation on the Growth, P and as Absorption of Astragalus Sinicus L. under Arsenic Stress

Author: SunXiaoBo
Tutor: ZhaoBin
School: Huazhong Agricultural University
Course: Microbiology
Keywords: AM fungi phosphorus arsenic Astragalus sinicus L quantitative PCR
CLC: S551.9
Type: Master's thesis
Year: 2011
Downloads: 30
Quote: 0
Read: Download Dissertation

Abstract


In recent years, with the development of ore mining, metal smelting and the application of arsenic compounds in agriculture and industry, arsenic contamination has been a very prominent global environmental problem and remained to be resolve urgently. Plants growing on arsenic polluted soils tend to be mycorrhizal and mycorrhizal fungi can enhance arsenate resistance of the host plants, so mycorrhizal fungi may play an important role in revegetation and phytostabilization of the arsenic contamination soil.The same host plant is often colonized by multiple AM fungus in the natural environment, therefore qualitative and quantitative analysis of the AM fungus in the roots plays a very important role in research on the interaction between plants and AM fungi or between the AM fungus. Conventional staining and nested PCR technology can not do that, but the appearance of fluorescence quantitative PCR technology is expected to overcome these deficiencies.In this paper, a new method using quantitative PCR technology to detect AM fungal DNA for qualitative and quantitative analysis was established and the correlation between the results from quantitative PCR and the colonization was also analysed. The role of different AM fungus and P application on growth, P and As absorption of Astragalus sinicus L growing in As polluted soil were studied by a pot experiment, and the colonization of AM fungi was quantificated using quantitative real-time polymerase chain reaction technique(real-time PCR).The results showed that:the primers designed had high specificity and sensitivity,and the quantity of AM fungal DNA detected by quantitative PCR has a high correlation with colonization rate, so the technology can be successfully applied to the qualitative and quantitative analysis for AM fungi in root segment. In the pot experiment, Gmosseae had more activity than Gintraradices under arsenic stress, and had dominant position in the coinoculation. As the concentration of arsenic increased, the colonization of Gintraradices decreased significantly while that of Gmosseae was less pronounced.However,the increase of phosphorus level inhibited the colonization of both Gintraradices and Gmosseae. Compared with uninoculated controls, AM plants had much higher biomass, P concentration, total P, P/As and lower As concentration. Futhermore, Gmosseae had more positive effects than Gintraradices on promoting growth and detoxification, coinoculation in the middle. With the increase of soil As concentration, the root P concentrations and As concentrations were increased gradually in both inoculated and uninoculated plants. However, the shoot P concentrations in the inoculation treatment did not change significantly, while in the uninoculated controls showed a downward trend; the shoot As concentration in the inoculation treatment showed no significant difference while in uninoculated controls increased. Furthermore, whether inoculated or uninoculated plants, the As concentrations in the root are generally 20-30 times higher than that in the shoot, the P concentrations in the root are 1.5-2 times higher than that in the shoot, especially under the arsenic stress conditions. The AM fungus may have been highly tolerant to As and conferred tolerance to As on the plant by enhancing plant P nutrition and restricting root As uptake.

Related Dissertations

  1. Phosphorus pentoxide composite ammoniated condensing agent preparation of ammonium polyphosphate,TQ314.248
  2. Lake Sediment Accumulation Areas of Yunnan Altiplano Ecological Conditions of Phosphorus and Nitrogen Interactions,X131.2
  3. Studies on the Quality of Phisio-Chemical and Fresh Keeping Technologies of Post-Harvest in Volvariella Volvacea,S646.13
  4. Yellow phosphorus storage tank area of Safety Evaluation,TQ126.317
  5. Gejiu tin metal mining areas arsenic contamination geochemical studies,X50
  6. Research on the Laws of Nitrogen and Phosphorus Loss and Control Scheme in Eryuan Rural,X712
  7. Studies on Key Planting Skills of Cigar-Wrapper Tabacco,S572
  8. Research on Influnce of Silicon and Sulfur on Arsenic Uptake and Accumulation of Rice (Oryza Sativa L.),S511
  9. Study on Nitrogen and Phosphorus Release Fluxes of Sediment-water Interface in Dutang Reservoir,X524
  10. A Study on Assessment and Early Warning System of Water Pollution Effect by Land Loadings in Taihu Lake Basin,X52
  11. Effects of Three Aquatic Plants on Soil Properties and Depletion of Rhizosphorus Nitrogen and Phosphorus,S154.4
  12. Study on Removal Efficiency of Organic Phosphorus Pesticides Residues by Ultrasonic and Air Bubble Cleaning,S481.8
  13. Gene Cloning and Expression Analysis of Odorant Receptor and Arginine Kinase Gene from Helicoverpa Assulta (Guenée),S433.4
  14. cDNA-cloning and Expression analysis of Phosphate Stress Induced Purple Acid Phosphatase Genes and transcription Factor Genes from Seeding Wheat,S512.1
  15. Effects of Different Applying Methods of Copper and Zinc and AM Fungi under Different P-Applied Levels on Growth and Tanshinones of Salviae Miltiorrhizae Bunge,S567.53
  16. Studies on the Characteristics of Japonica Rice Varieties Which Are the Most Widely Cultivated in Zhejiang Province,S511.22
  17. Screening of Phosphate Solubilizing Bacteria, Optimization of Phosphate Dissolving Conditions and Its Promotion to Maize Growth,S513
  18. Screening and Identification of Rice Cultivars with Relative High Nitrogen Use Efficiency for Tolerance to Low-Phosphate at Seedling Stage,S511
  19. Analysis of the Differentially Expressed Genes in Fingered Citron under Cold Stress,S666.9
  20. Accumulation and Leaching Risk of Phosphorus in Vegetable Soils under Intensive Cultivation,S63
  21. Proliferation Characteristics of Type 2 Porcine Circovirus Strains and Antivirus Activity of Iprs and Aps on PCV2 in Vitro,S858.28

CLC: > Agricultural Sciences > Crop > Green manure crops > Leguminous green manure > Other
© 2012 www.DissertationTopic.Net  Mobile