Summary The Ethiopian plateau hosts thousands of durum wheat ( Triticum turgidum subsp. durum ) farmer varieties ( FV ) with high adaptability and breeding potential. To harness their unique allelic diversity, we produced a large nested association mapping ( NAM ) population intercrossing fifty Ethiopian FV s with an international elite durum wheat variety (Asassa). The Ethiopian NAM population (Et NAM ) is composed of fifty interconnected bi‐parental families, totalling 6280 recombinant inbred lines ( RIL s) that represent both a powerful quantitative trait loci ( QTL ) mapping tool, and a large pre‐breeding panel. Here, we discuss the molecular and phenotypic diversity of the Et NAM founder lines, then we use an array featuring 13 000 single nucleotide polymorphisms ( SNP s) to characterize a subset of 1200 Et NAM RIL s from 12 families. Finally, we test the usefulness of the population by mapping phenology traits and plant height using a genome wide association ( GWA ) approach. Et NAM RIL s showed high allelic variation and a genetic makeup combining genetic diversity from Ethiopian FV s with the international durum wheat allele pool. Et NAM SNP data were projected on the fully sequenced AB genome of wild emmer wheat, and were used to estimate pairwise linkage disequilibrium ( LD ) measures that reported an LD decay distance of 7.4 Mb on average, and balanced founder contributions across Et NAM families. GWA analyses identified 11 genomic loci individually affecting up to 3 days in flowering time and more than 1.6 cm in height. We argue that the Et NAM is a powerful tool to support the production of new durum wheat varieties targeting local and global agriculture.

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In smallholder farming systems, traditional farmer varieties of neglected and underutilized species (NUS) support the livelihoods of millions of growers and consumers. NUS combine cultural and agronomic value with local adaptation, and transdisciplinary methods are needed to fully evaluate their breeding potential. Here, we assembled and characterized the genetic diversity of a representative collection of 366 Ethiopian teff (Eragrostis tef) farmer varieties and breeding materials, describing their phylogenetic relations and local adaptation on the Ethiopian landscape. We phenotyped the collection for its agronomic performance, involving local teff farmers in a participatory variety evaluation. Our analyses revealed environmental patterns of teff genetic diversity and allowed us to identify 10 genetic clusters associated with climate variation and with uneven spatial distribution. A genome-wide association study was used to identify loci and candidate genes related to phenology, yield, local adaptation, and farmers’ appreciation. The estimated teff genomic offset under climate change scenarios highlighted an area around lake Tana where teff cropping may 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.

About 15,000 M 2 seeds of ethyl-methane-sulphonate (EMS)-mutagenized population were screened along with Al-tolerant and sensitive checks and the M 0 variety. Strongly acidic soil with an external application of a toxic Al-solution and exposure to moisture stress was used to maximize selection pressure. Twenty-one M 2 plants with root lengths of greater than the mean of the tolerant check were selected and planted for seed production. Candidate M 3 plants were investigated for Altolerance and for morpho-agronomic traits under greenhouse and field conditions, respectively. Highly significant differences were observed for Al-tolerance between the candidate mutant lines and the M 0 (P < .001), and between mutant lines and the sensitive check (P < .001). Similarly, significant differences were observed between the mutant lines for 16 of the 20 quantitative traits measured. This study is the first to report successful induction of enhanced Al-tolerance in tef by using EMS mutagenized population. ARTICLE HISTORY