Microbial diversity determines the invasion of soil by a bacterial pathogen.
Natural ecosystems show variable resistance to invasion by alien species, and this resistance can relate to the species diversity in the system. In soil, microorganisms are key components that determine life support functions, but the functional redundancy in the microbiota of most soils has long been thought to overwhelm microbial diversity-function relationships. We here show an inverse relationship between soil microbial diversity and survival of the invading species Escherichia coli O157:H7, assessed by using the marked derivative strain T. The invader's fate in soil was determined in the presence of (i) differentially constructed culturable bacterial communities, and (ii) microbial communities established using a dilution-to-extinction approach. Both approaches revealed a negative correlation between the diversity of the soil microbiota and survival of the invader. The relationship could be explained by a decrease in the competitive ability of the invader in species-rich vs. species-poor bacterial communities, reflected in the amount of resources used and the rate of their consumption. Soil microbial diversity is a key factor that controls the extent to which bacterial invaders can establish.
Department of Microbial Ecology, Center for Evolutionary and Ecological Studies, University of Groningen, 9700 CC, Groningen, The Netherlands. j.d.van.elsas@rug.nl
Jan Dirk
JD
van Elsas
Mario
M
Chiurazzi
Cyrus A
CA
Mallon
Dana
D
Elhottova
Václav
V
Kristufek
Joana Falcão
JF
Salles
D044822:Biodiversity; D015169:Colony Count, Microbial; D019453:Escherichia coli O157 / Q000254:growth & development*; D058865:Introduced Species; D009426:Netherlands; D012988:Soil Microbiology; D016019:Survival Analysis; D013997:Time Factors