1. A STUDY ON THE BIOCONTROL
ACTIVITYAND PLANT GROWTH
PROMOTING ACTIVITY OF PSEUDOMONAS
FLUORECENS ISOLATED FROM SOIL
PRESENTED BY:
DIEP VAN MINH
Guided by
Dr. T. VINOTH KUMAR, M.Sc., M.Phil.
PGDCA, Ph.D.
ASSOCIATE PROFESSOR AND
DIRECTOR
BIOTECHNOLOGY DIVISION
SCHOOL OF BIOLOGICAL SCIENCES
CMS COLLEGE OF SCIENCE AND
COMMERCE
COIMBATORE

2. INTRODUCTION
 Biological control is defined broadly as the "use of natural or modified
organisms, genes, or gene products” to reduce the effects of pests and
diseases.
 As we know bofore Pseudomonas Fluorecensen showed a high degree
of antagonism against the phytopathogen
 It promote plant growth.
 Fungi of the genus Fusarium are necrotrophic pathogens that infect
crops in all regions of cultivation to cause root rot, foot rot.
 Fusarium species produces one or more mycotoxins. The Fusarium
causes systemic infections of wheat plants by attacking their roots,
stems, and spikes.

3. AIM OF THE PRESENT STUDY
 Collection of soil sample
 Isolation and characterization of the organism
 Screening and identification of the organism
 Screening and identification of the phytopathogen
 Antagonistic activity of the organism against
phytopathogen
 Plant growth promoting effect of the organism

4. MATERIAL AND METHOD
Isolation of Pseudomonas Fluorescence: the bacteria were isolated from soil
sample which is collected from different areas parts of Kerala and Tamil Nadu by
using King’B medium.
Maintenance of pure culture: The selected colonies were steaked on to Centrimide
Agar Medium plates to obtain pure culture.
Screening and Identification of Pseudomonas fluorescens.
1. Gram staining
2.Culture Method
3. Biochemical characterization
• IMVC test.
• Oxidase test.
• Catalase test.
• Triple sugar iron test.

5. Screening and identification of pathogenic
fungi.
 The sample was collected from Tamil Nadu
Agriculture University (TNAU).
 Microscopic examination of pathogenic fungi.
 Sub culturing of pathogen in medium.

6. Antagonistic activity of Pseudomonas against
Fusarium mysporum
o Antagonist, activity of Pseudomonas strain was tested against Fusarium mysporum
by using dual culture technique. It can be done in 3ways.
• Method I.
• Method II.
• Method III.
Plant growth promoting activity.

7. Results
Gram staining of the organism Cetrimide agar plates showing green
colour colonies under UV

8. Pseudomonas Fluorecense under UV (360nm)

9. Bio-chemical characterization
Citrate utilization test Triple sugar iron test

10. Indole test Methyl red test Voges-Proskauer Test
Catalase test

11. Biochemical Test of Bacterial isolation
Sl.No Test Results
1. Indole -
2. Methyl red -
3. Voges-proskauer -
4. Simmon citrate +
5. Catalase test +
6. Oxidase test +
7. TSI test +

12. Screening and identification of pathogenic fungi.
PDA plate of Fusarium oxysporum

13. Antagonistic activity of Pseudomonas
against Fusarium mysporum
Method I Method II

14. Method III

15. Plant growth promoting activity

16. Plant Infection

17. Healthy Plant

18. SUMMARY AND CONCLUSION
The present study the antagonistic activity of Pseudomonas
fluorescens against the major phytopathogen Fusarium was tested.
The Pseudomonas fluorescens was isolated from soil sample
collected from different part of Kerala and Coimbatore.The
phytopathogen was collected from TNAU, Coimbatore, dual plate
culture technique revealed that the Pseudomonas Spp isolated
show antagonistic activity against the phytopathogen.
The plant growth promoting efficacy of the Pseudomonas Spp was
also studied . The organism showed enhance the growth of Soya
bean when compare to the seed that was untreated.