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International audience; LC-HRMS Q-TOF method was used to identify and quantify metabolites ofFoleyola billotiiMaire plant. A series of 15 compounds were tentatively identified: three glucosinolates, 2 aliphatic (progoitrin and gluconapin) and 1 indolic (glucobrassicin); six chlorogenic acids, four coumaroyl quinic acid (CoQA) isomers and two feruloyl quinic acid (FQA) isomers; two diglycosylated flavonols, one quercetin-derived and one kaempferol-derived; three sinapic acid derivatives, sinapoyl threonic acid, hexose sinapate and a third derivative supposedly attributed to a feruloyl quinic acid sinapate; and finally, a glycosylatedtrans-cinnamic acid which could correspond to feruloylthreonic acid (FTA). Glucosinolates content was 55 times higher in cultivated plants; chlorogenic acids and flavonols increased too by 5 and 3.5 times, respectively. In contrast, sinapates decreased by 3 times in cultivated plants, this last result can be explained by reduced UV-B intensity in the north of Algeria. The change inF. billotiicompound profile was more quantitative rather than qualitative.

International audience; In the hermaphroditic plants, floral morphological traits can significantly affect reproductive system by favouring the deposit of self or cross pollen. In the Brassica species, the self-incompatibility mechanism is undoubtedly the main cause of their allogamy; however, floral organs variation can modulate or reinforce the cross pollination level of the plants. In this study, we investigated floral variation among wild populations of Brassica rapa L. from Algeria. We estimated 20 floral traits, including sepals, petals, pistil, stamens and nectaries as well as ovules production. Floral parameters were measured using stereomicroscope. Each flower's ovule number and stigma-anther separation were also quantified under dissecting microscope. We found that all the flower parameters vary among populations or among individuals, especially stigma surface, nectary surface and stigma-anther separation. These three parameters have a coefficient of variation greater than 18,9%. Moreover, the individual variation is different according to the populations. These results suggest that floral morphology may affect pollination efficiency and as a consequence seed production in B. rapa wild populations but with different contributions according to the floral traits

Self-incompatibility (SI) is thought to have played a key role in the evolution of species as it promotes their outcrossing through the recognition and rejection of self-pollen grains. In most species, SI is under the control of a complex, multiallelic S-locus. The recognition system is associated with quantitative variations of the strength of the SI reaction; the origin of these variations is still not elucidated. To define the genetic regulations involved, we studied the variability of the SI response in homozygous S 15 S 15 plants in cauliflower. These plants were obtained from a self-progeny of a self-compatible (SC) plant heterozygous for S 15 , which was generated after five selfing generations from one strongly self-incompatible initial plant. We found a continuous phenotypic variation for SI response in the offspring plants homozygous for the S 15 haplotype, from the strict SI reaction to self-compatibility, with a great proportion of the plants being partially self-compatible (PSC). Decrease in SI levels was also observed during the life of the flower. The number of pollen tubes passing through the stigma barrier was higher when counted 3 or 5 days after pollination than one day after pollination. Analysis of the expression of the two key genes regulating self-pollen recognition in cauliflower, the S-locus receptor kinase (SRK) and S-locus cysteine-rich (SCR/SP11) genes, revealed that self-compatibility or PSC was associated with decreased SRK or SCR/SP11 expression. Our work shows the particularly high level of phenotypic plasticity of the SI response associated with certain S-haplotypes in cauliflower.

International audience; Polyploidy or whole genome duplication is a frequent and recurrent phenomenon in flowering plants that has played a major role in their diversification, adaptation and speciation. The adaptive success of polyploids relates to the different evolutionary fates of duplicated genes. In this study, we explored the impact of the whole genome triplication (WGT) event in the Brassiceae tribe on the genes involved in the self-incompatibility (SI) signalling pathway, a mechanism allowing recognition and rejection of self-pollen in hermaphrodite plants. By taking advantage of the knowledge acquired on this pathway as well as of several reference genomes in Brassicaceae species, we determined copy number of the different genes involved in this pathway and investigated their structural and functional evolutionary dynamics. We could infer that whereas most genes involved in the SI signalling returned to single copies after the WGT event (i.e. ARC1, JDP1, THL1, THL2, Exo70A01) in diploid Brassica species, a few were retained in duplicated (GLO1 and PLDα) or triplicated copies (MLPK). We also carefully studied the gene structure of these latter duplicated genes (including the conservation of functional domains and active sites) and tested their transcription in the stigma to identify which copies seem to be involved in the SI signalling pathway. By taking advantage of these analyses, we then explored the putative origin of a contrasted SI phenotype between two Brassica rapa varieties that have been fully sequenced and shared the same S-allele (S60).