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On-Site Molecular Detection of Soil-Borne Phytopathogens Using a Portable Real-Time PCR System
Published on: February 23, 2018
PCR-based identification of Bacillus thuringiensis isolated from soil samples in Nigeria
A A Ogunjimi1, G O Gbenle, D K Olukoya
1Department of Biochemistry, College of Medicine of the University of Lagos, Nigeria.
Zeitschrift Fur Naturforschung. C, Journal of Biosciences
|February 24, 2001
Summary
PCR techniques differentiated Bacillus thuringiensis soil isolates toxic to mosquito larvae. DNA analysis revealed specific crystal protein genes, enhancing understanding of these potent biological control agents.
Area of Science:
- Microbiology
- Molecular Biology
- Entomology
Background:
- Bacillus thuringiensis (Bt) is a soil bacterium known for its insecticidal properties.
- Mosquito control is crucial for public health, and Bt isolates are promising biological agents.
- Accurate identification and characterization of Bt isolates are essential for effective application.
Purpose of the Study:
- To differentiate and characterize Bacillus thuringiensis isolates from soil samples using molecular techniques.
- To confirm the presence of delta-endotoxin genes responsible for insecticidal activity.
- To compare the efficacy of serological and PCR-based identification methods.
Main Methods:
- Isolation of Bacillus thuringiensis from soil samples.
- Serological identification of selected isolates.
- Polymerase Chain Reaction (PCR) amplification of delta-endotoxin (cry) genes.
- Analysis of PCR amplicon sizes for differentiation.
Main Results:
- Six Bacillus thuringiensis isolates toxic to mosquito larvae were identified.
- PCR analysis confirmed the presence of cryI a, b, c, or II genes in at least four isolates.
- No amplicons were detected for Cry IV A, B, and D genes in the tested isolates.
- One isolate identified by PCR remained unidentified by serological methods.
Conclusions:
- PCR-based techniques provide effective differentiation of Bacillus thuringiensis isolates.
- The presence of specific cry genes correlates with toxicity to mosquito larvae.
- Molecular methods offer complementary identification capabilities to traditional serological techniques.
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