Abstract
Faba bean (Vicia faba L.) is a facultative cross-pollinating legume crop with a great importance for food and feed due to its high protein content as well as the important role in soil fertility and nitrogen fixation. In this work we evaluated genetic diversity and population structure of faba bean accessions from the Western Mediterranean basin and wild related species. For that purpose we screened 53 V. faba, 2 V. johannis and 7 V. narbonensis accessions from Portugal, Spain and Morocco with 28 faba bean Single Sequence Repeats (SSR). SSR genotyping showed that the number of alleles detected per locus for the polymorphic markers ranged between 2 and 10, with Polymorphic Information Content (PIC) values between 0.662 and 0.071, and heterozygosity (HO) between 0–0.467. Heterozygosity and inbreeding coefficient levels indicate a higher level of inbreeding in wild related species than in cultivated Vicia. The analysis of molecular variance (AMOVA) showed a superior genetic diversity within accessions than between accessions even from distant regions. These results are in accordance to population structure analysis showing that individuals from the same accession can be genetically more similar to individuals from far away accessions, than from individuals from the same accession. In all three levels of analysis (whole panel of cultivated and wild accessions, cultivated faba bean accessions and Portuguese accessions) no population structure was observed based on geography or climatic factors. Differences between V. narbonensis and V. johannis are undetectable although these wild taxa are clearly distinct from V. faba accessions. Thus, a limited gene flow occurred between cultivated accessions and wild relatives. Contrastingly, the lack of population structure seems to indicate a high degree of gene flow between V. faba accessions, possibly explained by the partially allogamous habit in association with frequent seed exchange/introduction.
Highlights
Faba bean (Vicia faba L.) is an annual diploid legume (2n = 2x = 12) and the seventh most produced legume worldwide with a yield of 3,503,300 tons in 2013 (FAOSTAT)
The results obtained for all markers and all accessions in our panel are detailed in S1 Table
For the markers tested, observed heterozygosity (HO) ranged from 0 (GBSSR-VF-34 and 276) to 0.467 (GBSSR-VF-52). These values are similar to the range between 0.000 and 0.500 reported by Gong, Xu [25] in a study of 11 Single Sequence Repeats (SSR) in 29 accessions from China and Europe, but lower than the values observed in a trial of 150 SSRs in 32 worldwide accessions (0.091 to 0.841) [12]
Summary
Faba bean (Vicia faba L.) is an annual diploid legume (2n = 2x = 12) and the seventh most produced legume worldwide with a yield of 3,503,300 tons in 2013 (FAOSTAT). It was one of the earliest domesticated legume species, with remains identified in Near Eastern sites as early as 10,700 BP [1]. It is a facultative cross-pollinating with outcrossing rates varying between 1–55% depending on environments [2]. V. johannis is a wild species of the V. narbonensis complex with agronomic interest for breeders due to increased frost tolerance and resistance to biotic stresses [6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
