Symbiont abundance is more important than pre-infection partner choice in a Rhizobium - legume mutualism.
It is known that the genetic diversity of conspecific rhizobia present in root nodules differs greatly among populations of a legume species, which has led to the suggestion that both dispersal limitation and the local environment affect rhizobial genotypic composition. However, it remains unclear whether rhizobial genotypes residing in root nodules are representative of the entire population of compatible symbiotic rhizobia. Since symbiotic preferences differ among legume populations, the genetic composition of rhizobia found within nodules may reflect the preferences of the local hosts, rather than the full diversity of potential nodulating rhizobia present in the soil. Here, we assessed whether Vicia cracca legume hosts of different provenances select different Rhizobium leguminosarum genotypes than sympatric V. cracca hosts, when presented a natural soil rhizobial population. Through combining V. cracca plants and rhizobia from adjacent and more distant populations, we found that V. cracca hosts are relatively randomly associated with rhizobial genotypes. This indicates that pre-infection partner choice is relatively weak in certain legume hosts when faced with a natural population of rhizobia.
Plant Conservation and Population Biology, Biology Department, KU Leuven, Kasteelpark Arenberg 31, B-3001 Leuven, Belgium; Centre of Microbial and Plant Genetics, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium. Electronic address: jannick.vancauwenberghe@bio.kuleuven.be.
Jannick
J
Van Cauwenberghe
Plant Conservation and Population Biology, Biology Department, KU Leuven, Kasteelpark Arenberg 31, B-3001 Leuven, Belgium.
Benny
B
Lemaire
Faculty of Biology, Alexandru Ioan Cuza University of Iasi, Bd. Carol I 20A, 700505 Iasi, Romania.
Andrei
A
Stefan
Department of Experimental and Applied Biology, NIRDBS-Institute of Biological Research Iasi, Lascar Catargi 47, 700107 Iasi, Romania.
Rodica
R
Efrose
Centre of Microbial and Plant Genetics, KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium.
Jan
J
Michiels
Plant Conservation and Population Biology, Biology Department, KU Leuven, Kasteelpark Arenberg 31, B-3001 Leuven, Belgium.
Olivier
O
Honnay
D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D014644:Genetic Variation / Q000235:genetics; D005838:Genotype; D005843:Geography; D017351:N-Acetylglucosaminyltransferases / Q000235:genetics; D011938:Rec A Recombinases / Q000235:genetics; D016961:Rhizobium leguminosarum / Q000235:genetics* / Q000254:growth & development*; D053204:Root Nodules, Plant / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D013559:Symbiosis; D031306:Vicia / Q000382:microbiology*
D001426:Bacterial Proteins; D012987:Soil; D017351:N-Acetylglucosaminyltransferases; C060771:NodC protein, Rhizobiales; D011938:Rec A Recombinases
Pre-infection partner choice; Rhizobia; Rhizobium leguminosarum biovar viciae; Symbiont preference; Vicia cracca