Which seed origin provides better tolerance to flooding and drought when restoring to face climate change?

Abstract

Our goal was to establish the tolerance to flooding and drought of seedlings from a hydric gradient of different seed sources to provide recommendations for forest restoration in the face of climate change. We used Drimys winteri var. chilensis, a tree species that grows from extreme arid zones to wetlands along Chile, as the study subject. We expected that seedlings of xeric origin would perform better in drought conditions than populations from moist environments, and vice versa for flooding tolerance. We collected D. winteri seeds from xeric, mesic and wet environments. Seedlings at two development stages were submitted to an extreme flooding and drought treatment during 2 or 4 months in a common garden. After the flooding and drought assays finished, the number of surviving and damaged seedlings, lenticels and adventitious root presence, height, new leaves and specific leaf area, shoot/root ratio, water potential and/or chlorophyll fluorescence (Fv/Fm), were recorded. We found that flooding and drought affected almost all the parameters studied negatively. The xeric population seedlings, at both development stages studied, were the most tolerant to the drought and, unexpectedly, also to the flooding treatment. We recommend restoring with seedlings of xeric origin especially in arid areas where sudden flooding is frequent, as occurs in the Andes Mountains. In the face of climate change, we recommend carrying out common garden and field studies before advising which population origin should be used for restoration, since they do not always respond in accordance with expected patterns of local adaptation.

Polyphasic studies of new species of Diaporthe from native forest in Chile, with descriptions of Diaporthe araucanorum sp. nov., Diaporthe foikelawen sp. nov. and Diaporthe patagonica sp. nov.

“…chilensis, a small evergreen tree commonly found in the swamp forests and lowlands of Chile and Argentina. The variety chilensis occurs from Salamanca to Aysén (32-42°S), including Chilóe Island [46]. The multilocus phylogenetic analysis showed D. foikelawen close to D. araucanorum and D. beckhausii.…”

Conservation of adaptive potential and functional diversity: integrating old and new approaches

“…Landscape genomics, combining phylogeographic patterns with detailed environmental data (Gugger et al 2018) also could aid in the restoration and preservation of either particular threatened species or larger communities (Montalvo et al 1997;Funk et al 2008), by informing practical decisions about what to preserve, how and over what geographic scales (McKay et al 2005). Relating genomic variation to critical phenotypic responses to environmental stress (Bustos-Salazar et al 2017;Vangestel et al 2018) can be used to inform selection of individuals to use for restoration or breeding programmes for sustainably harvested populations. Combining remote sensing (Turner et al 2003;Vihervaara et al 2017) and ecological niche modelling (May et al 2011;De La Torre et al 2014) with conservation genetics is also a powerful way to predict future adaptation.…”