Among thè new contaminants relevant for our environment, one of thè most significant roles is surely played by pharmaceutical products for either human or veterinary use. The environmental impact of these products has been thè object of thè attention of thè academic and legislative world for a few decades. Numerous studies have highlighted thè presence of tetracyclines. in varying concentrations, in sediment and surface waters (Jjemba, 2002; Kong et al.. 2007: Blackwell et al.. 2009). For example, their average concentration in agricultural land ranges from 450 to 900 micrograms per kg'1 (Xie et al.. 2011). At a site in Germany, Tetracycline was found at a concentration of 4.0 mg per kg'1 in soil fertilized with liquid fertilizer (Hamscher et al.. 2002). Some toxicity tests have shown that Tetracycline and Clortetracycline inhibit thè activity of Daphnia magna. Danio rerio and Cyprinus carpio (Bao, 2008: Zhang et al.. 2008). The presence of antibiotics in thè soil could cause serious damage to soil bacteria and microfauna. Many studies have been carried out on thè effects of tetracyclines and antibiotics on free-living nematodes (Hagerbaumer et al.. 2015) and these studies have shown that antibiotics in generai and tetracyclines in particular (Vangheel. 2012) seriously compromise thè survival of these nematodes. Little is known about thè interaction between antibiotics and EPN. Entomopathogenic nematodes (EPN) have been used. during thè last decades. for biological control of crops. for their ability to penetrate and kill arthropods thanks to a complex symbiotic mechanism with specific gram-negative bacteria belonging to thè Enterobacteriaceae family. Tetracycline is an antibiotic used in human and veterinary medicine, both for therapeutic purposes and for thè growth of livestock. Since its action against gram-negative bacteria is well known, we verified in this study thè survival, growth and pathogenicity of two species of EPNs. Steinernema vulcanicum and S. feltiae. Both nematode species were kept in thè presence of tetracycline. We have studied: 1 ) The survival capacity of thè two species of EPN in Tetracycline 2) Growth capacity. mutation at adults and reproduction in Tetracycline: tests in insect hemolymph. 3) The entomopathogenic capacity of thè nematodes after 24 and 48 h in tetracycline. 4) The action of Tetracycline on thè EPNs’ endosymbionts Xenorhabdus kozodoi and X. bovieni All tests were performed with tetracycline in 1% ethanol solution and 600 mg / 1 concentration. Apparently, this incubation did not harm thè vitality of EPNs; moreover. their development was unaffected in thè case of S. vulcanicum, as well as its entomopathogenic potential. However, S.feltiae while maintaining its vitality and its entomopathogenic ability, did not grow nor reproduce in thè hemolymph of Galleria mellonella larvae and their endosymbionts did not grow on McConkey Agar. The results suggest that thè first species has retained all its abilities and therefore that endosymbionts have acquired resistance to tetracycline, while experiments with thè second species have given contrasting results that will require further investigations.

First trial on the effect of Tetracycline on Entomophatogenic Nematodes (EPNs)

Clausi M.
Membro del Collaboration Group
;
Leone D.
Membro del Collaboration Group
;
Rappazzo G.
Membro del Collaboration Group
;
Mulder C.
Membro del Collaboration Group
;
Conti E.
Membro del Collaboration Group
2018-01-01

Abstract

Among thè new contaminants relevant for our environment, one of thè most significant roles is surely played by pharmaceutical products for either human or veterinary use. The environmental impact of these products has been thè object of thè attention of thè academic and legislative world for a few decades. Numerous studies have highlighted thè presence of tetracyclines. in varying concentrations, in sediment and surface waters (Jjemba, 2002; Kong et al.. 2007: Blackwell et al.. 2009). For example, their average concentration in agricultural land ranges from 450 to 900 micrograms per kg'1 (Xie et al.. 2011). At a site in Germany, Tetracycline was found at a concentration of 4.0 mg per kg'1 in soil fertilized with liquid fertilizer (Hamscher et al.. 2002). Some toxicity tests have shown that Tetracycline and Clortetracycline inhibit thè activity of Daphnia magna. Danio rerio and Cyprinus carpio (Bao, 2008: Zhang et al.. 2008). The presence of antibiotics in thè soil could cause serious damage to soil bacteria and microfauna. Many studies have been carried out on thè effects of tetracyclines and antibiotics on free-living nematodes (Hagerbaumer et al.. 2015) and these studies have shown that antibiotics in generai and tetracyclines in particular (Vangheel. 2012) seriously compromise thè survival of these nematodes. Little is known about thè interaction between antibiotics and EPN. Entomopathogenic nematodes (EPN) have been used. during thè last decades. for biological control of crops. for their ability to penetrate and kill arthropods thanks to a complex symbiotic mechanism with specific gram-negative bacteria belonging to thè Enterobacteriaceae family. Tetracycline is an antibiotic used in human and veterinary medicine, both for therapeutic purposes and for thè growth of livestock. Since its action against gram-negative bacteria is well known, we verified in this study thè survival, growth and pathogenicity of two species of EPNs. Steinernema vulcanicum and S. feltiae. Both nematode species were kept in thè presence of tetracycline. We have studied: 1 ) The survival capacity of thè two species of EPN in Tetracycline 2) Growth capacity. mutation at adults and reproduction in Tetracycline: tests in insect hemolymph. 3) The entomopathogenic capacity of thè nematodes after 24 and 48 h in tetracycline. 4) The action of Tetracycline on thè EPNs’ endosymbionts Xenorhabdus kozodoi and X. bovieni All tests were performed with tetracycline in 1% ethanol solution and 600 mg / 1 concentration. Apparently, this incubation did not harm thè vitality of EPNs; moreover. their development was unaffected in thè case of S. vulcanicum, as well as its entomopathogenic potential. However, S.feltiae while maintaining its vitality and its entomopathogenic ability, did not grow nor reproduce in thè hemolymph of Galleria mellonella larvae and their endosymbionts did not grow on McConkey Agar. The results suggest that thè first species has retained all its abilities and therefore that endosymbionts have acquired resistance to tetracycline, while experiments with thè second species have given contrasting results that will require further investigations.
2018
Entomopathogenic nematodes (EPN, Tetracycline, Bacteria
File in questo prodotto:
File Dimensione Formato  
First trials.pdf

solo gestori archivio

Descrizione: Abstract di comunicazione a congresso
Tipologia: Versione Editoriale (PDF)
Dimensione 1.06 MB
Formato Adobe PDF
1.06 MB Adobe PDF   Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11769/374552
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact