INVESTIGADORES
MATHIASEN Paula
congresos y reuniones científicas
Título:
Differential adaptive responses to drought of Nothofagus dombeyi from contrasting precipitation regimes
Autor/es:
DIAZ, D.G.; MATHIASEN, P.; PREMOLI, A.C.
Lugar:
Bariloche
Reunión:
Conferencia; International Conference TOPWOOD; 2019
Institución organizadora:
European Union Marie-Curie project TOPWOOD, the International Associated Laboratory INRA (France)- INTA (Argentina) FORESTIA and the INTA EEA Bariloche (IFAB INTA ? CONICET) - Forest Research Unit, Argentina
Resumen:
Climate change hardly impacts on natural systems and the evidence that shows it is increasingly solid. Tree species? distribution margins may present adaptive features for unfavorable conditions such as drought. Nothofagus dombeyi that inhabits humid forests, has suffered from massive mortality as a result of recent extreme droughts. The aim is to study genetic differences and potential adaptive responses to drought in N. dombeyi analyzing the dry and humid extremes of its distribution, based on water stress manipulative experiments and molecular markers with potential adaptive value.Recently germinated N. dombeyi seedlings from sites with contrasting precipitation regimes were cultivated in a common garden where survival and morphology (leaf and plant) was monitored. A set of plants from the two origins were subjected to water deficit experiments for a period of three weeks. Then the water potential was measured with a pressure chamber and the number of stomas was counted. Potential genetic differences among seedlings were analyzed with Single Nucleotide Polymorphisms (SNPs).The predawn and midday water potentials showed no statistically significant differences between drought and control. The humid site showed an anisohydric behavior with stomatal control when water shortage in the soil begins; while the dry site may have an isohydric behavior, with stomatal control more adapted to drought conditions. We found 102 adaptive SNPs loci that discriminated between the origins of plants. Five of them had a significant relationship with different architectural variables. The results show that drought-resistant genotypes have been selected in the dry environments of the N. dombeyi distribution with potential adaptive value.