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This work represents the first epigenomic study carried out on saffron crocus. Five accessions of saffron, showing differences in tepal pigmentation, yield of saffron and flowering time, were analyzed at the epigenetic level by applying a methylation-sensitive restriction enzyme-sequencing (MRE-seq) approach. Five accession-specific hypomethylomes plus a reference hypomethylome, generated by combining the sequence data from the single accessions, were obtained. Assembled sequences were annotated against existing online databases. In the absence of the Crocus genome, the rice genome was mainly used as the reference as it is the best annotated genome among monocot plants. Comparison of the hypomethylomes revealed many differentially methylated regions, confirming the high epigenetic variability present among saffron accessions, including sequences encoding for proteins that could be good candidates to explain the accessions’ alternative phenotypes. In particular, transcription factors involved in flowering process (MADS-box and TFL) and for the production of pigments (MYB) were detected. Finally, by comparing the generated sequences of the different accessions, a high number of SNPs, likely having arisen as a consequence of the prolonged vegetative propagation, were detected, demonstrating surprisingly high genetic variability. Gene ontology (GO) was performed to map and visualize sequence polymorphisms located within the GOs and to compare their distributions among different accessions. As well as suggesting the possible existence of alternative phenotypes with a genetic basis, a clear difference in polymorphic GO is present among accessions based on their geographic origin, supporting a possible signature of selection in the Indian accession with respect to the Spanish ones.

A total of 125 accessions of one-flowered vetch (Vicia articulata Hornem.) mostly from the Iberian Peninsula have been analysed for total protein, L-canavanine and condensed tannins. It was observed a high variability in the composition: the protein content ranged from 18.20 to 30.07%, L-canavanine from 0.27 to 0.67%, and condensed tannins from 0.13 to 0.35%, which indicates a scarce domestication of the crop. The inclusion of the seeds into a diet to nonruminants should be limited to marginal percentages because of the contents of L-canavanine and it suggests that a reduction of this compound by breeding should be encouraged. The protein and the L-canavanine contents showed a low and positive significant correlation (r = 0.55, P \ 0.001), which complicates the selection of seeds having simultaneously low L-canavanine and high protein contents. On the other hand, no correlation between protein and condensed tannins or between L-canavanine and condensed tannins was observed. There was a poor relationship between the origin and the composition of the accessions and only the protein content was able to discriminate among the regions.