Isolation and identification chitinolytic bacteria from plan rhizosphere soil and their potential in antifungal biocontrol
Subject Areas : Environmental Microbiology
Tahereh Salahinezhad
1
,
Zoheir Heshmatipour
2
,
Masoud Hashemikaroui
3
1 - MS.c., Department of Microbiology, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.
2 - Associate Professor, Department of Microbiology, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.
3 - Associate Professor, Department of Microbiology, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.
Keywords: Fusarium solani, 16S rRNA, chitinase, Potential anti-fungal,
Abstract :
Background and Objectives: Chitinase is one of the most important industrial enzymes, which is recently employed especially in the biological control of pathogenic fungi. This study was aimed to isolate and to identify the chitin degrading bacteria obtained from the rhizosphere soil and also to evaluate their antifungal ability. Materials and Methods: In this study, 38 soil samples from the rhizosphere of tea plants, Geranium and clover were collected randomly. After serial dilution and growth of the samples on colloidal chitin agar (CCA), the isolates with a clear zone were chosen for further studies. The presence of Chitinase enzyme was measured by a spectrophotometer. Next, we determined the antifungal activity of the isolates against Fusarium solani. Finally, the isolates were identified based on polymerase chain reaction and sequencing 16S rRNA genes. Results: In this study, only one new strain referred to as Serratia Salahi strains was isolated which showed the chitin degrading activity. The highest enzymatic activity (4.37 U/ml) of this strain was obtained at 30°C after 4 days. Furthermore, the antifungal activity of this bacterium could create 1.5 cm inhibition zone. Conclusion: According to the findings, this new strain can be used as a natural pesticide and therefore, it is possible to replace the synthetic pesticides with this natural compounds.
