Bridging landscape genomics and quantitative genetics for a regional adaptation of European grasslands to climate change (GRASSLANDSCAPE)

This project will deliver fundamental genomic knowledge about the natural biodiversity in European grasslands. Each of these grasslands has, via spontaneous adaptation, adjusted to the geographical and climatological circumstances. Study of the genomic differences that occur is interesting for various reasons. The aim of the GRASSLANDSCAPE project is to apply new knowledge about biodiversity to support future grasslands in coping with climate change, including periods of drought and more extreme weather. Grasslands are important ecosystems and they form the basis of dairy and meat production. Previous research has shown that the current local grass populations are not capable of maintaining their current level of productivity under unusual weather circumstances. This project starts with the observation that most grassland types show a great ecotypical diversity when studied over a large geographical area (e.g., Europe). This is the diversity that we wish to use to combine natural climatological conditions with characteristics that guarantee high yields and feed quality.

The landscape genomics approach should deliver a usable screening of the natural diversity within the most important grass species – perennial ryegrass – in terms of environmental adaptation, and more specifically adjustment to climatological conditions. We collect more than 500 populations of perennial ryegrass, spread over the entire area of Europe, North Africa and the East, which have been left to evolve in a natural way over several generations. These populations are sown on three (experimental) field locations in Europe, including at ILVO (Melle, Belgium). In these controlled circumstances, we phenotype them to determine their agronomical and eco-physiological characteristics. In parallel, genotyping is performed. We implement genotyping by sequencing (GBS) methods based on NGS technology. Then we use association models between genomic polymorphisms and environmental variation to map the spatial distribution of genomic diversity linked to adaptation under current climate conditions. Finally we come to an interesting combination of correlations between genomic polymorphism in populations and the ecological characteristics of their place of origin, and the so-called “signature of selection”. The “landscape genomics” methodology makes it possible to predict possible changes under various climate change scenarios such as described in IPCC AR5.

Grassland as a type of landscape delivers important ecosystem services. Grasslands are essential to dairy and meat production. A direct practical application comes when we can define the allelic profiles of perennial ryegrass that are best suited for the expected new climatological circumstances. We expect that the adaptation to future climate conditions and good agricultural practices can be combined in one set of genetic pools. These genetic pools can support the breeding programs that target better adaptation to our future regional climates. Recent occurrences such as the severe drought in western Europe in 2003 point the agricultural sector and the plant researchers to the imminent and severe risks for damage and severe production losses due to climate change. In addition, improved populations can also be used in grassland restoration programs.