. Vertebrate feces as sources of nodulating Frankia in Patagonia.

EUGENIA E. CHAIA & MARIA C. SOSA & ESTELA RAFFAELE

SYMBIOSIS

SPRINGER

Lugar: Berlin; Año: 2012 vol. 56 p. 139 - 145

0334-5114

Abstract Frankia strains nodulate the native actinorhizalplant Ochetophila trinervis (sin. Discaria trinervis), whichgrows in stream margins and nearby areas in northwestPatagonia (Argentina). Infective Frankia are found in soilswith presence of host plants but also may be found in areaslacking them. This may be partly explained by water transportof Frankia propagules but there are other possible sources.The aim of this study was to discover whether the faeces ofintroduced mammalian herbivores, including cows (Bostaurus, adult and calf), horses (Equus caballus), sheep (Ovisaries), red and/or fallow deer (Cervus elaphus and Damadama, respectively), wild boar (Sus scrofa), European hare(Lepus capensis), or the native upland goose (Chloephagapicta), could be a source of infective Frankia, and enhanceits dispersal. Faecal material and soil samples were asepticallysampled in different plant communities, and tested via plantbioassays using O. trinervis. The faeces of all animalscontained infective Frankia and led to an effective symbiosiswith this plant. Faeces of large introduced herbivores gave riseto higher nodulation (number of nodulated plants with respectto the total number of inoculated plants) than faeces of hareand upland goose. Soils from the sites where the cow (twosites), sheep, wild boar and deer faeces were collected did notcontain infective Frankia. This suggests that the animals mayhave ingested Frankia from plant material and that theFrankia propagules passed through the digestive tracts ofthe animals without losing its infectivity. We conclude thatthe faeces of large introduced herbivores contribute to thedispersal of infective Frankia in Northwest Patagonia.Keywords Actinorhizal symbiosis .