Canal-U

[COLLOQUE] GENTREE Final Conference 27-31 January 2020 séance 2

GENTREE Final Conference :

Antoine KREMER - INRAE Bordeaux · France

GENTREE Final Conference 'Genetics to the rescue - managing forests sustainably in a changing environment'

27-31 January 2020, Avignon, France

http://www.gentree-h2020.eu/

Antoine KREMER - INRAE Bordeaux · France : How does contemporary selection shape oak phenotypes?

Most existing forests are subject to natural and human-mediated selection pressures, which have increased due to climate changes and the increasing needs of human societies for wood, fiber and fuel resources.

It remains largely unknown how these pressures trigger evolutionary changes for various phenotypic traits. We address this issue here for temperate European oaks (Quercus petraea and Q. robur), which grow in mixed stands, under even-aged management regimes.

We reconstructed genetic relatedness across two generations and estimated in natura selection differentials and fitness.

We screened numerous functional traits for univariate selection gradients, and over two successive generations for expected and observed genetic changes. In both species, growth, leaf morphology and physiology, and defense-related traits displayed significant selection gradients and predicted shifts, whereas phenology, water metabolism, structure and resilience-related traits did not. However, the direction of the selection response and the potential for adaptive evolution differed between the two species.

Quercus petraea had a larger phenotypic and genetic variance of fitness.

This difference raises concerns about the adaptive response of Q. robur to contemporary selection pressures. Our investigations suggest that Q. robur will probably decline steadily, particularly in mixed stands with Q. petraea, consistent with the contrasting demographic dynamics of the two species.