Trifolium species associate with a similar richness of soil‐borne mutualists in their introduced and native ranges

Abstract

AbstractAimWhile plant species introduced to new regions may benefit from escaping natural enemies, their success may be impaired by losing key mutualists. We aimed to elucidate whether a selection of annual and perennial Trifolium (clover) species have lost associations with nitrogen‐fixing bacteria (rhizobia) and arbuscular mycorrhizal fungi (AMF) in their introduced range.LocationIntroduced range in New Zealand (NZ) and native range in the United Kingdom (UK).MethodsWe compared the strain richness of rhizobia associated with five Trifolium species in both ranges using genetic fingerprinting (rep‐PCR with ERIC primers). Phylogenetic analysis of the nodD gene was conducted to test for between‐range differences in rhizobia genotypes associated with seven Trifolium species. We also used TRFLP to compare the richness of AMF associated with three Trifolium species in both ranges.ResultsGenetic fingerprinting indicated that Trifolium associate with a similar richness of rhizobia strains in NZ as they do in the UK. According to variation in the nodD gene, genotypes of rhizobia were indistinguishable between NZ and UK provenances. A total of 17 AMF operational taxonomic units were detected but there were no significant between‐range differences in richness or in community structure.Main conclusionsContrary to general expectations regarding the loss of mutualists following species introduction, our findings suggest that alien plants, including those accidentally introduced, can have access to rich communities of soil‐borne mutualists that are likely to facilitate successful naturalization.