Data-driven, participatory characterization of traditional farmer varieties discloses teff (Eragrostis tef) adaptive and breeding potential under current and future climates

In smallholder farming systems, traditional farmer varieties of neglected and underutilized crops species (NUS) support the livelihoods of millions of growers and consumers. NUS combine cultural and agronomic value with local adaptation, and call for transdisciplinary methods to evaluate their breeding potential. Here, we combined farmers' traditional knowledge, genomics, and climate science to characterize 366 Ethiopian teff (Eragrostis tef) farmer varieties and breeding materials. We found that teff genetic diversity in Ethiopia could be organized in six genetic clusters associated to climate variation on the landscape. A participatory evaluation conducted in collaboration with local farmers could consistently identify best performing varieties and inform a genome wide association study to identify candidate genes for farmers' appreciation, phenology, yield, and local adaptation. By modelling the genomic adaptation of teff to current and projected climates, we identified an area around lake Tana where teff cropping will be most vulnerable to climate change. Our results show that transdisciplinary approaches may efficiently propel untapped NUS farmer varieties into modern breeding to foster more resilient and sustainable cropping systems