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International audience; The hop plant (Humulus lupulus L.) has been exploited for a long time for both its brewing and medicinal uses, due in particular to its specific chemical composition. These last years, hop cultivation that was in decline has been experiencing a renewal for several reasons, such as a craze for strongly hopped aromatic beers. In this context, the present work aims at investigating the genetic and chemical diversity of fifty wild hops collected from different locations in Northern France. These wild hops were compared to ten commercial varieties and three heirloom varieties cultivated in the same sampled geographical area. Genetic analysis relying on genome fingerprinting using 11 microsatellite markers showed a high level of diversity. A total of 56 alleles were determined with an average of 10.9 alleles per locus and assessed a significant population structure (mean pairwise FST = 0.29). Phytochemical characterization of hops was based on volatile compound analysis by HS-SPME GC-MS, quantification of the main prenylated phenolic compounds by UHPLC-UV as well as untargeted metabolomics by UHPLC-HRMS and revealed a high level of chemical diversity among the assessed wild ac-cessions. In particular, analysis of volatile compounds revealed the presence of some minor but original com-pounds, such as aromadendrene, allo-aromadendrene, isoledene, fl-guaiene, alpha-ylangene and fl-pinene in some wild accessions; while analysis of phenolic compounds showed high content of fl-acids in these wild accessions, up to 2.37% of colupulone. Genetic diversity of wild hops previously observed was hence supported by their chemical diversity. Sample soil analysis was also performed to get a pedological classification of these different collection sites. Results of the multivariate statistical analysis suggest that wild hops constitute a huge pool of chemical and genetic diversity of this species.

International audience; Most thermally processed foods are affected by the Maillard reaction which leads to the formation of not only desired flavor and aroma compounds but also neoformed contaminants with probable unwanted biological effects. Among the latter, acrylamide was found to be formed from free asparagine in plant foods such as potatoes, cereals and coffee. Roasted chicory which is used as a common coffee substitute is also known to be high in acrylamide and indicative values have been proposed for this food category by the European Commission. The current study is aimed at understanding the impact of varietal selection and agronomic practices on the concentration of free asparagine, a major acrylamide precursor, in chicory roots, and the effect of these parameters on the amount of acrylamide in roasted chicory. The study showed that the concentration of free asparagine in raw chicory roots was variety- and year-dependent (from 444 to 2786 mg/kg). All five varieties tested showed an increase in free asparagine level in response to increased nitrogen application. The duration of chicory cultivation and the date of harvest had limited effects which need to be further understood. The drying process reduced free asparagine concentration in chicory roots without generating acrylamide. Overall the reduction of free asparagine in the raw chicory roots tested in this study led to a significant decrease in acrylamide formation in the roasted chicory (from 11097 to 2249 mu g/kg). This positive correlation does not exclude the possibility that other factors such as those related to roasting conditions could be involved in the acrylamide formation.

International audience; High-density genetic maps were constructed for loci involved in nuclear male sterility (NMS1-locus) and sporophytic self-incompatibility (S-locus) in chicory (Cichorium intybus L.). The mapping population consisted of 389 F1' individuals derived from a cross between two plants, K28 (male-sterile) and K59 (pollen-fertile), both heterozygous at the S-locus. This F1' mapping population segregated for both male sterility (MS) and strong self-incompatibility (SI) phenotypes. Phenotyping F1' individuals for MS allowed us to map the NMS1-locus to linkage group (LG) 5, while controlled diallel and factorial crosses to identify compatible/incompatible phenotypes mapped the S-locus to LG2. To increase the density of markers around these loci, bulked segregant analysis was used. Bulks and parental plants K28 and K59 were screened using amplified fragment length polymorphism (AFLP) analysis, with a complete set of 256 primer combinations of EcoRI-ANN and MseI-CNN. A total of 31,000 fragments were generated, of which 2,350 showed polymorphism between K59 and K28. Thirteen AFLP markers were identified close to the NMS1-locus and six in the vicinity of the S-locus. From these AFLP markers, eight were transformed into sequence-characterized amplified region (SCAR) markers and of these five showed co-dominant polymorphism. The chromosomal regions containing the NMS1-locus and the S-locus were each confined to a region of 0.8 cM. In addition, we mapped genes encoding proteins similar to S-receptor kinase, the female determinant of sporophytic SI in the Brasicaceae, and also markers in the vicinity of the putative S-locus of sunflower, but none of these genes or markers mapped close to the chicory S-locus.