Counter‐gradient variation of reproductive effort in a widely distributed temperate oak

Abstract

The genetic and phenotypic variability of life‐history traits determines the demographic attributes of tree populations and, thus, their responses to anthropogenic climate change. Growth‐ and survival‐related traits have been widely studied in forest ecology, but little is known about the determinism of reproductive traits. Using an elevation gradient experiment in the Pyrenees, we assessed the degree to which variations in reproductive effort along climatic gradients are environmentally or genetically driven, by comparing oak populations (Quercus petraea) growing under field and common garden conditions. In situ monitoring revealed a decline in reproductive effort with increasing elevation and decreasing temperature. In common garden conditions, significant genetic differentiation was observed between provenances for reproduction and growth: trees from cold environments (high elevations) grew more slowly, and produced larger acorns in larger numbers. Our observations show that genetic and phenotypic clines for reproductive traits have opposite signs (counter‐gradient) along the environmental gradient as opposed to growth, for which genetic variation parallels phenotypic variation (co‐gradient). The counter‐gradient found here for reproductive effort reveals that genetic variation partly counteracts the phenotypic effect of temperature, moderating the change in reproductive effort according to temperature. We consider the possible contribution to this counter‐gradient in reproductive effort as an evolutionary trade‐off between reproduction and growth. A free Plain Language Summary can be found within the Supporting Information of this article.

Oak stands along an elevation gradient have different molecular strategies for regulating bud phenology

“…4 ). It should be also noticed that our results are also in accordance with those of [ 79 ]. Indeed, these authors reported that at low elevation natural selection favors vegetative growth than reproduction thus explaining the early flushing date observed at low elevation.…”

Integrated Application of Transcriptomics and Metabolomics Reveals the Energy Allocation-Mediated Mechanisms of Growth-Defense Trade-Offs in Crassostrea gigas and Crassostrea angulata

“…Trade-offs between traits are common ecological and evolutionary phenomenon in nature, as they ensure the best use of outside resources . Trait trade-offs are particularly common in plants and sessile marine ectotherms because these types of organisms cannot shift their locality to avoid environmental variation (Karasov et al, 2017;Zust and Agrawal, 2017;Chauvin et al, 2018;Min et al, 2018;Caignard et al, 2021). Plenty of studies demonstrated that the trade-offs between reproduction, growth, and survival are the key forces that structure life-history variation (Culina et al, 2019;Cohen et al, 2020;Roach and Smith, 2020).…”

Leaf functional traits and ecological niche of Fagus grandifolia and Oreomunnea mexicana in natural forests and plantings as a proxy of climate change

“…For example, to cope with environmental changes along an elevational gradient, plants in natural forests and plantings can adjust morphologically and physiologically, reducing LA, SLA, and increasing leaf thickness at higher elevations (Velázquez‐Rosas et al, 2002; Umaña and Swenson, 2019). Studies on functional traits and elevational gradients also indicate that intraspecific variability may result from phenotypic plasticity or genetic diversity (Conover and Schultz, 1995; Caignard et al, 2021). Some studies in plants on the extent of trait variation driven by environmental and/or genetic factors have provided evidence of countergradient variation where genetic and environmental effects are in opposite directions (Caignard et al, 2021).…”

“…Studies on functional traits and elevational gradients also indicate that intraspecific variability may result from phenotypic plasticity or genetic diversity (Conover and Schultz, 1995; Caignard et al, 2021). Some studies in plants on the extent of trait variation driven by environmental and/or genetic factors have provided evidence of countergradient variation where genetic and environmental effects are in opposite directions (Caignard et al, 2021). Also, the lack of variation in some traits across gradients may be due to constraints or countergradients that maintain phenotypes across the environment (Umaña and Swenson, 2019).…”