Detection and enumeration of Pseudomonas aeruginosa in soil and manure assessed by an ecfX qPCR assay.

Aims: To develop a qPCR approach for the detection of Pseudomonas aeruginosa in soil and manure and explore its efficacy and limitations compared with that of a classical culture-dependent approach.

Methods And Results: A Ps. aeruginosa ecfX qPCR assay was developed.

Zn speciation in the organic horizon of a contaminated soil by micro-X-ray fluorescence, micro- and powder-EXAFS spectroscopy, and isotopic dilution.

Soils that have been acutely contaminated by heavy metals show distinct characteristics, such as colonization by metal-tolerant plant species and topsoil enrichment in weakly degraded plant debris, because biodegradation processes are strongly inhibited by contamination. Such an organic topsoil, located downwind of an active zinc smelter and extremely rich in Zn (approximately 2%, dry weight), was investigated by X-ray diffraction, synchrotron-based X-ray microfluorescence, and powder- and micro-extended X-ray absorption fine structure (EXAFS) spectroscopy for Zn speciation and by isotopic dilution for Zn lability. EXAFS spectra recorded on size fractions and on selected spots of thin sections were analyzed by principal component analysis and linear combination fits.