Dissertation > Excellent graduate degree dissertation topics show

Isolation of the Pathogen of the Root-Rot Disease of Atractylodes Macrocephala Koidz and Screening of Its Antagonistic Bacteria

Author: ZhengChaoCheng
Tutor: WangWeiWu
School: Nanjing Agricultural College
Course: Microbiology
Keywords: root-rot disease of Atractylodes macrocephala Koidz Fusarium sp FO14 antagonistic bacteria Serratia sp. FS14
CLC: S435.672
Type: Master's thesis
Year: 2010
Downloads: 9
Quote: 0
Read: Download Dissertation

Abstract


Root-rot disease, also called dry-rot disease, was a serious disease of the cultivated Atractylodes macrocephala Koidz. The rhizomes of diseased plants would turn to be swollen and decayed with a brown colour at the cutting interface of the rhizomes. Finally, the disease led the plant to die, resulting in a remarkable loss to the farmers.A suspicious pathogen of the root-rot disease was isolated from the root tissue of the diseased Atractylodes macrocephala Koidz and four antagonistic bacteria strains were also isolated from the rhizosphere soil of the healthy Atractylodes macrocephala Koidz which was culviated in Jurong, the major cultivation place in Jiangsu Province. The fungus was identified as a species of Fusarium and named as Fusarium sp. FO14 by combining the morphology of the asexual spores and the analysis of its ITS sequence. The isolate with best anti Fusarium sp. FO14 activity was chosen for the further study. It was identified as Bacillus and named as Bacilllus sp. BS14 by combining the physiological, biochemical characters and the analysis of the 16S rDNA sequence. The antifungal activity against some other plant pathogen was also studied.A strain FS14 producing red pigment was also isolated from the stem of the diseased plant during the isolation of the pathogen of root-rot disease of Atractylodes macrocephala Koidz. Combined with the traditional physiological and biochemical characterization and the analysis of the 16s rDNA sequence, the isolate was named as Serratia sp. FS14.. The isolate could grow in a wide pH range from pH 4 to pH 10 and could grow in LB medium with 0-10% sodium chloride. Surprisingly, thermostable extracellular DNase and protease were detected in the supernatant of the culture of Serratia sp. FS14 while this strain was a mesophile microorganism. This is the first time to report thermostable extracellular enzymes from Serratias, so it deserved to be further study.

Related Dissertations

  1. Preparation and Biological Effects of a Bio-Organic Fertilizer Against Banana Fusarium-Wilt Disease,S436.68
  2. Screening, Identification of Antagonistic Organisms Against Phytophthora Capsici and Effect of Their Bio-Organic Fertilizer on Pepper,S436.418
  3. Screening of Antagonistic Bacterium Against Alternaria Alternata and Determination of Control Effect of the Bacterium on Alternaria Alternata,S435.72
  4. Screening, Identification and Antagonism of Antifungal Strains,S432.44
  5. Basic Study for Isolation and Identification of Antagonistic Bacteria Colonizing Melon Fruit Surface and Assessment as Biocontrol Agents to Postharvest Disease Pathogens,S476
  6. Screening and Application of Antifungal Bacteria Against Fusarium Oxysporum F.sp. Cubense,S436.68
  7. Screening, Identification of Antagonistic Organisms Against R. Solanacearum and Effect of Their Bio-Organic Fertilizer of Eggplant,S436.411
  8. Studies on Pest Risk Analysis, Identification, Detection and Antagonistic Bacteria of Burkholderia Glumae,S435.111.4
  9. On Production Conditions,Physi-Chemical Characteristics,Mechanism and Disease Prevention of Bacillus B1 and B2 Antifungal Substances,S482.292
  10. Of antagonistic bacteria rice sheath blight evaluation, monitoring and utilization,S435.111
  11. Study on Antagonistic Bacteria for Biocontrol of the Fusarium Wilt,S476.1
  12. The Community Structure of Banana Endophytes and Antagonistic Bacteria Against Fusarium Oxysporum f.sp. Cubense in Banana,S436.68
  13. Identification and Fermentation of Bacillus Cereus C332, Isolation and Characterization of Its Antibacterial Substance,Q93
  14. Comparison of the Genomovars of Burkholderia Cepacia Complex from the Farmland and Hospital,R378
  15. Studies on Postharvest Physiology and Storage Techniques of Pepper,S641.3
  16. Mechanisms of Antagonists and Chemical Compounds Against Postharvest Diseases and Cloning of Disease Resistant Genes from Fruit,S476.8
  17. Evaluation of Inhibitory Effect of Biocontrol Agents Bacillus Isolates on Aquaculture-Conditional Pathogenic Bacteria and Protective Roles in the Culture of Eirocheir Sinensis, Macrobrachium Nipponnensic and Trionyx Sinensis,S948
  18. Isolation and Identification of Probiotics from Gut of Flounder and Its Use in Aquaculture,S917.1
  19. Screening, Identification and Antagonism of Antagonistic Organisms Against Phytopathogene,S476.1
  20. Changes in Physical and Chemical Properties of the Medium During CO2 Enrichment by Fermentation of Organic Wastes and the Effect of Its Residues on Improving Soil Fertility,S141.4

CLC: > Agricultural Sciences > Plant Protection > Pest and Disease Control > Crop pests and diseases and their prevention > Economic crop pests and diseases > Medicinal crop pests and diseases > Herbal crop pests and diseases
© 2012 www.DissertationTopic.Net  Mobile