Journal of Pure and Applied MicrobiologyVol. 8 No. May 2014 Special Edition

Effects of Inoculating Earthworms on Degradation of Pyrene in the Rhizosphere Soils Growing Sorghum sudanese

Shengwang Pan1, Mingcheng Hu1, Maoping He1, Lijuan Yang1, Zhihua Lei2 and Xin Yuan3*

1School of Urban and Rural Construction, Chengdu University, Chengdu - 610106, China. 2School of Medical Laboratorial Technics, Xinyang Vocational & Technical College, Xinyang - 465350, China. 3Department of Barracks Management & Environment Engineering, LEU, Chongqing-401131, China.

Received on 12 April 2014 and accepted on 09 May 2014

 

ABSTRACT

The potentials of Sudan grass, with or without inoculating earthworms, on the degradation of hydrophobic organic contaminants (HOCs) in soils were estimated by pot experiments. Results showed that plantation of vegetation enhanced loss of HOCs at initial contents ranging from 20.24 to 321.42 mg/kg. During the 70-d incubation, about 801.84~539.99? of pyrene was removed from planted soils, and only 242.28~122.79? degradation of pyrene occurred in non-planted soils. After inoculating earthworms, the dissipation ratios of pyrene in planted soils were increased up to 863.94~609.63?, which was 77.27~129.14? higher than those in corresponding soils without earthworms. Among all possible pathways, contribution of plant-microbial interactions on dissipation of pyrene was the most significant, either with (456.73?) or without inoculating earthworms (515.58?) and were the primary means of contaminant degradation. Results suggested a feasible way for the establishment of high efficiency rhizoremediation of HOCs with inoculating earthworms, which may be especially beneficial for reinforcing removal of HOCs containing more benzene rings in molecules.

Keywords : Rhizoremediation, Pyrene, Plant-microbial interactions, Sudan grass, Earthworm.