Co-occurring patterns of endophyte infection and genetic structure in the alpine grass, Festuca eskia: implications for seed sourcing in ecological restoration

Abstract

Choosing the provenance of seed used in ecological restoration could entail its success. An alternative approach to examine local adaptation in seed sourcing is the assessment of genetic structure and diversity based on molecular markers. These types of analyses focus on the genetics of the target plant itself and eliminate the genetic influence of associated organisms, such as Epichloe¨/Neotyphodium endophytes in grasses. By impacting the fitness of their host, such symbionts may influence population genetic structure and diversity. Therefore, seed sourcing for grasses must consider the influence of their endophytes to increase seed translocation success and minimize the risks associated with this practice. To delineate seed zones for restoration of the alpine fescue Festuca eskia Ramond ex. DC. (Poaceae), we assessed population genetic differentiation and diversity patterns in the species including endophyte occurrence along altitudinal and longitudinal gradients in the Pyrenees Mountains. Twenty-three populations were analysed for endophyte status, and three STS and one SSR marker were used to examine genetic differentiation and diversity patterns. Results showed that F. eskia hosts an asexual form of Epichloe¨and infection frequency within populations decreased from East to West (100 vs. 8-25%). Molecular markers separated F. eskia into two East and West groups, and endophyte infection and genetic patterns were congruent with molecular data. Little evidence for genetic differentiation or difference in endophyte occurrence associated with altitude was detected. Little variation was found in within population diversity, regardless of provenance altitude and site, and/or endophyte infection frequency. The results of this study suggested the establishment of two distinct management units for F. eskia seed sourcing restoration.

Postglacial colonization history reflects in the genetic structure of natural populations of Festuca rubra in Europe

“…Similar levels of genetic variability with no differentiation between the E+ and E− plants in Spain suggest that individual plants have common historical origins despite differing endophyte status in the region. Similarly, no differences have been found in genetic diversities among endophyte‐infected and uninfected plants in Festuca eskia populations in the Pyrenees in southern Europe, near suggested refugium areas (Gonzalo‐Turpin et al, ). Similar local patterns of genetic diversities among infection groups can be promoted by several underlying processes, for example, the production of both infected and noninfected offspring by the same infected plants.…”

Contribution of genetics to ecological restoration

“…), clustering methods (Broadhurst ), spatial autocorrelation (Krauss & Koch ), isolation by distance calculated through Mantel tests (Gonzalo‐Turpin et al . ) and estimation of gene flow (Tanaka et al . ).…”

Biotic and abiotic predictors of fungal colonization in grasses of the Colorado Rockies

“…By constraining hosts to a single functional group, we reduced confounding effects of hosts' ecological roles. Prior altitudinal surveys of grass-fungal symbioses have focused on a single fungal group and a single or small number of host species (Fisher & Fule, 2004;Granath et al, 2007;Gonzalo-Turpin et al, 2010;Kirkby et al, 2011;Casper et al, 2012;Lugo et al, 2012).…”

“…Read & Haselwandter, 1981;Schmidt et al, 2008). Too few data are available to draw generalizations for the LFE (Fisher et al, 1995;Hashizume et al, 2008;Cordier et al, 2012) or epichloae (Granath et al, 2007;Gonzalo-Turpin et al, 2010;Kirkby et al, 2011). Despite clear evidence for host specificity of fungal symbionts (Becklin et al, 2012;Unterseher et al, 2013b), few studies have evaluated the degree to which fungal symbiont distributions vary amongst host species (but see, Granath et al, 2007).…”