isolation and characterization of fenitrothion-degrading bacteria from pestachio gardens in kerman provinance

  Introduction : Pesticides with complex structure have high persistence in ecosystem and biosphere. Pesticides have harmful effects on farmlands, human and natural resources.   Materials and methods: In this study for isolation of pesticide-degrading bacteria (Fenitrothion) soil samples were collected from pistachio gardens in Kerman province. Collected soil samples were enriched in Bushnell Hass medium with this pesticide as only carbon and energy source. Isolated bacteria were identified by amplification of 16S rDNA gene by PCR and sequencing .   Results : In this study three Fenitrothion -degrading bacterial strains were isolated. These isolated bacteria were identified as: Pseudomonas fluorescens strain F1 ، Bacillus cereus strain F3 and pseudomonas aeruginosa strain F4 . The effects of pesticides concentration on each dominant bacterial strain were investigated. For Fenitrothion degrading bacterium (F4 strain) growth continue until 100 ppm and then decreased. The result of Gas Chromatography (GC) analysis confirmed the biodegradation ability of selected bacterial strains .   Discussion and conclusion : The results of this study demonstrated that there is a diversity of pesticide-degrading bacteria (Fenitrothion) in soil ecosystem farmlands of Kerman province. It is seemed by application of these pesticide-degrading bacteria in farmlands and using bioremediation technique the ecosystem contamination of pesticide can be decreased.