Isolation and characterization of Bifenthrin degrading fungal isolates from acclimatized soil

Bifenthrin is a third generation synthetic pyrethroid. Field soil of IARI was enriched with bifenthrin for 1 year aerobically in laboratory. Three fungal strains capable to use this insecticide as a sole source of carbon were isolated from this acclimatized soil. These strains were purified and acclimatized to bifenthrin at higher concentration level in laboratory. A supplemental carbon source was required to trigger the metabolic reaction. Bifenthrin was degraded at a faster rate in inoculated mineral salt medium (MSM) than uninoculated MSM. Within 40 days, nearly 35% bifenthrin was degraded in inoculated medium while only 6-7 % of insecticide was degraded in uninoculated medium. Of three fungal strains, two fungal strains were identified as Aspergillus sp. on the basis of their morphological characteristics. The third strain was a non sporulating fungus, therefore it was identified on the basis 28Sr DNA sequence and was identified as Achaetomium strumarium. Probably, this is the first report implicating Achaetomium strumarium in bifenthrin degradation.