INVESTIGADORES
GRESLEBIN Alina Gabriela
congresos y reuniones científicas
Título:
AFLP analysis reveals low genetic diversity of Phytophthora austrocedrae in Patagonia, Argentina
Autor/es:
VÉLEZ, M.L.; COETZEE M.P.A.; WINGFIELD M.J.; RAJCHENBERG M.; GRESLEBIN, A.G.
Lugar:
Córdoba
Reunión:
Congreso; 6th Workshop of IUFRO Working Party 7.02.09 Phytophthora in Forests and Natural Ecosystems; 2012
Institución organizadora:
IUFRO, Universidad de Córdoba
Resumen:
Phytophthora
austrocedrae is a recently discovered pathogen that causes high levels
of mortality of Austrocedrus chilensis
in Patagonia. The susceptibility of the host tree together with the dispersal
pattern of the pathogen in Patagonia led to the hypothesis that P. austrocedrae was introduced into Argentina.
But the genetic diversity of the pathogen that would better inform this
question has not been determined. The
aim of this study was, therefore, to assess the population structure of P. austrocedrae
isolates from Argentina in order to gain an understanding of the origin and
spread of the pathogen. Genetic diversity was determined based on amplified
fragment length polymorphisms (AFLPs). In total, 48 isolates of P. austrocedrae were obtained from
infected A. chilensis trees, and these
represented the geographical range of the host. Four primer combinations were
used for the AFLP analysis. Of the 332 scored
bands, 12% were polymorphic. Gene diversity (h) ranged from 0.0050-0.0258 and the Shannon index (I) from 0.0180-0.0432. A high degree of
genetic similarity was observed among the isolates (pairwise S values= 958-1; 0.993± 0.009, mean±S.D).
A frequency histogram showed that most of the isolate pairs were 100% similar. Principal
coordinate analysis using three-dimensional plots did not group any of the isolates
based on their geographical origin. The low genetic diversity (within and
between sites) and absence of population structure linked to geographic origin,
suggest that P. austrocedrae was introduced into Argentina.