Bioaugmentation of carbofuran residues in soil by Burkholderia cepacia PCL3: A small-scale field study

A small-scale field study was conducted in 1 m x 1.25 m x 20 cm plots. In the soil with only indigenous microorganisms, carbofuran degradation was slow with a long half-life (t(1/2)) of 127 d. Bioaugmenting the soil with the immobilized PCL3 could shorten the t(1/2) of carbofuran to 16 d. The t(1/2) rose to a significantly longer 28 d when the free cells of PCL3 were used instead of the immobilized cells. Viable cell counting of carbofuran degraders in soil indicated that the carbofuran degradation efficiency directly correlated to the number of introduced carbofuran degraders that survived in the system. PCL3 in free-cell form did not survive in the soil during the field operation; this suggested that the immobilization of PCL3 is needed in order to implement the bioaugmentation technique in a real environment. (C) 2011 Elsevier Ltd. All rights reserved.