Agro-ecology: diversity in grasslands key to facing climate change

For optimal production of forage in grasslands, it is best to plant several species of crops, each with genetic diversity (several genotypes of the same species). In a ground-breaking study, INRA researchers, in collaboration with the CNRS, showed the positive and complementary effects of both species diversity and genetic diversity within species (intra-species diversity) in grasslands that are subject to drought. Genetic diversity may well be key to boosting the productivity, quality and sustainability of agricultural systems faced with climate change.

Agricultural landscape in Côte d'Or (Burgundy). © INRA, SLAGMULDER Christain
Updated on 08/11/2015
Published on 06/08/2015

How can we adapt agricultural production systems to better cope with global warming? One solution consists of tapping into species diversity and genetic diversity in crops to better handle unpredictable climatic changes and rise to the environmental challenges of tomorrow (low input, maintaining associated biodiversity, etc.). INRA researchers in Lusignan teamed up with the CNRS to test the combined effect of species diversity (a mix of species) and genetic diversity (mix of genotypes within each species) of sown grasslands on the production of forage crops and their stability in a context of limited water supply.

124 micro-communities

In concrete terms, the research teams ran experiments in semi-controlled conditions: they compared monocultures and a mix of species in 124 micro-communities in pots (micro-plots of 50 cm X 50 cm) using five different species (orchardgrass, fescue, ray-grass, white clover and alfalfa). Moreover, each mono-species and multi-species micro-community was replicated using one, five or ten genotypes per species, and subjected to two different types of water regimes: dry or irrigated.

Species diversity against drought, genetic diversity for yield stability

The results show a positive and complementary effect of both types of diversity - species and genetic - in grassland cover. While species diversity improves the production of cumulated biomass in the context of limited water, genetic diversity significantly improves stability, with more regular production throughout the year regardless of the water supply.

INRA scientists are now replicating this experiment on micro-plots in the field, but they have already shown that species and genetic diversity can be beneficial and complementary for optimising forage production in sown grasslands. Science should be tapping into these two types of diversity to implement programmes to improve and select plants likely to boost productivity and stability in a context of climate change.

Contact(s)
Scientific contact(s):

  • Isabelle Litrico (05 49 55 61 48) Multidisciplinary Research Unit for Grasslands and Forage Crops

reference

Ivan Prieto, Cyrille Violle, Philippe Barre, Jean-Louis Durand, Marc Ghesquière, Isabelle Litrico. Complementary effects of species and genetic diversity on productivity and stability of sown grasslands, Nature Plants, 30 March 2015