Sharing resources: Ectomycorrhizae of Pseudotsuga menziesii invading Nothofagus forests in Patagonia, Argentina.

SALGADO SALOMÓN M.E.; RAJCHENBERG M.; PILDAIN M. B.; BARROETAVEÑA C.

Buenos Aires

Simposio; 32 New Phytologist SymposiumPlant interactions with other organisms: molecules, ecology and evolution; 2013

IFEVA-Universidad de Buenos Aires and IIB-Universidad Nacional de San Martín, CONICET

The widely introduced Pseudotsuga menziesii presents invading characteristics in Nothofagus forests from Patagonia, Argentina. We studied richness and abundance of ectomycorrhizae (EM) in P. menziesii and Nothofagus from six Nothofagus+P. menziesii invasion matrices. Tramp seedlings from each species were set up in a soil-bioassay including soil from non-invaded Nothofagus forest, the effective recruitment area (ERA) and pure P. menziesii plantation. EM morphotypes were determined by molecular techniques. Hebeloma mesophaeum and Wilcoxina sp. EM were found to be shared by both tree species. P. menziesii EM colonization showed a decreasing pattern from the plantation to the non-invaded forest but also a good nursering effect provided by the neighboring plantations. Different EM colonization patterns were found in Nothofagus seedlings, being significantly lower in the ERA. This correlated with high seedlings? mortality at ERA, possibly due to an allelopatic effect by P. menziesii. Distances between forests and plantations did not limit EM inoculum since seedlings? colonization was never zero. Forest policies with fast-growing conifers should consider that P. menziesii presents powerful means to invade native Nothofagus forests.