Low occurrence of Pseudomonas aeruginosa in agricultural soils with and without organic amendment

Abstract

The occurrence of Pseudomonas aeruginosa was monitored at a broad spatial scale in French agricultural soils, from various soil types and under various land uses to evaluate the ability of soil to be a natural habitat for that species. To appreciate the impact of agricultural practices on the potential dispersion of P. aeruginosa, we further investigated the impact of organic amendment at experimental sites in France and Burkina Faso. A real-time quantitative PCR (qPCR) approach was used to analyze a set of 380 samples selected within the French RMQS (“Réseau de Mesures de la Qualité des Sols”) soil library. In parallel, a culture-dependent approach was tested on a subset of samples. The results showed that P. aeruginosa was very rarely detected suggesting a sporadic presence of this bacterium in soils from France and Burkina Faso, whatever the structural and physico-chemical characteristics or climate. When we analyzed the impact of organic amendment on the prevalence of P. aeruginosa, we found that even if it was detectable in various manures (at levels from 103 to 105 CFU or DNA targets (g drywt)−1 of sample), it was hardly ever detected in the corresponding soils, which raises questions about its survival. The only case reports were from a vineyard soil amended with a compost of mushroom manure in Burgundy, and a few samples from two fields amended with raw urban wastes in the sub-urban area of Ouagadougou, Burkina Faso. In these soils the levels of culturable cells were below 10 CFU (g drywt)−1.

Impact of untreated urban waste on the prevalence and antibiotic resistance profiles of human opportunistic pathogens in agricultural soils from Burkina Faso

“…It has to be noted that the number of S. maltophilia colonies on plates was always below ten and that variations were observed between samples from the same field, as some samples led to the detection of S. maltophilia whereas most of the others did not. As reported earlier (Deredjian et al 2014), no P. aeruginosa was detected in the control and amended soils from the 2008 campaign among all sites. None of the 30 samples from the 2011 sampling campaign at the Tabtenga site except one from the amended field site led to a direct isolation of P. aeruginosa.…”

“…Regarding opportunistic pathogens, P. aeruginosa is known to be present in animal-and human-originating waste (Lavenir et al 2007;Deredjian et al 2014). We were not able to detect P. aeruginosa following the 2008 campaign but we did detect that species in some samples from the 2011 campaign.…”

“…Reports from the literature indicated that some pathogens such as Escherichia coli, Campylobacter jejuni, Yersinia enterolitica, and Listeria monocytogenes can enter the soil through the spread of sewage sludge, municipal solid waste (Garrec et al 2003;Semenov et al 2009), and organic waste of animal origin (Meng and Doyle 1997;Farzan et al 2010). Despite a few reports on the presence of Pseudomonas aeruginosa in farmyard manures (Colinon et al 2013;Deredjian et al 2014), composted industrial waste (Kaszab et al 2011), and wastewater treatment plants (Lavenir et al 2007;Lee et al 2008;Edrington et al 2009), little data is available regarding the presence and behavior of opportunistic pathogens in water or solid waste used for agriculture practices in the environment.…”

Diversity of free-living amoebae in soils and their associated human opportunistic bacteria

“…These observations are original, because in previous reports, most virulent species of P. aeruginosa or B. cepacia were isolated from clinical environments (Leitao et al 2010;Streeter et al 2016) and few data are available concerning the virulence properties of soil isolates belonging to these species. Furthermore, P. aeruginosa bacteria are rarely isolated from soil due to its low occurrence in this environment (Selezska et al 2012;Deredjian et al 2014). Also, both virulent and non-virulent phenotypes were observed for the two isolates of S. maltophilia.…”

ThePseudomonas aeruginosaaccessory genome elements influence virulence towardsCaenorhabditis elegans

“…It is plausible that C. elegans and P. aeruginosa interact in natural niches, as the bacterium is known to inhabit 54 many environments including soils (Deredjian et al, 2014;Kaszab et al, 2011;Rutherford et al, 2018) and the nematode 55…”