Isolation of Mucor circinelloides Z4 and Mucor racemosus Z8 from heavy metal-contaminated soil and their potential in promoting phytoextraction with Guizhou oilseed rap

摘要

Fungi Z4 and Z8, isolated from the heavy metal polluted soil, have strong resistance to Cd and Pb. The strains were identified on the base of their morphology and internal transcribed spacers (ITS) region. Pot experiments were conducted to study the effect of two strains (Z4 and Z8) on the growth and accumulation of Cd and Pb of Guizhou oilseed rape. The results show that strains Z4 and Z8 belong to Mucor circinelloides and Mucor racemosus, respectively. The heights of Guizhou oilseed rape inoculated with strain Z8 increase by 47.90% than the control. The highest fresh mass is found in the plant with Z4/Z8, which is enhanced by 160.81%. Pot experiments show that Z4/Z8 inoculums can accelerate accumulation of heavy metals in the plant. The contents of Cd and Pb are increased by 117.60%and 63.48%, respectively. Meanwhile, the heavy metal concentrations in potting soil with the two strains are found to be lower than those of the control, and the concentrations of Cd and Pb are decreased by 60.57%and 27.12%, respectively.