Genetic Diversity and GxE Interactions for Drought and Disease Tolerance in Oat

Oat crop is not particularly adapted to hot and dry weather, as shown by a 3-fold yield reduction in Mediterranean compared to Northern regions. In addition, one of the main factors responsible for oat yield losses and yield instability in Mediterranean rim are fungal diseases. Indeed, Mediterranean crown rust populations are more virulent than those from the centre and north of Europe. In this workshop we will explain our work devoted to explore the potential of Spanish and other Mediterranean landraces for adapting to drought, high temperatures and diseases, through genetic diversity studies. Selection of agro-climate adapted genotypes is not straight-forward since they are strongly affected by the genotype-environment interaction. Thus, heritability-adjusted genotype plus genotype-environment biplot analyses were used to identify the oat performance under multiple stress environments, ideal cultivars, mega-environments, and core testing sites. The impact of climate variables on agronomic traits and the adaptation of particular landraces to environmental factors is also under study through non-metric multivariate scaling and canonical correspondence analyses. Furthermore, genome wide association analysis have been performed to associate desired phenotypes with particular genomic regions taking into account these genotype-environment interactions. The results confirmed that landraces are valuable sources of new allelic diversity for breeding programmes and ideal candidates to test for oat adaptation, agronomic performance and disease resistance under variable environments. In addition several markers have been associated with agronomic traits including rust resistance.