An expanded genetic linkage map of an intervarietal Agaricus bisporus var. bisporus x A. bisporus var. burnettii hybrid based on AFLP, SSR and CAPS markers sheds light on the recombination behaviour of the species

International audienceA genetic linkage map for the edible basidiomycete Agaricus bisporus was constructed from 118 haploid homokaryons derived from an intervarietal A. bisporus var. bisporus × A. bisporus var. burnettii hybrid. Two hundred and thirty-one AFLP, 21 SSR, 68 CAPS markers together with the MAT, BSN, PPC1 loci and one allozyme locus (ADH) were evenly spread over 13 linkage groups corresponding to the chromosomes of A. bisporus. The map covers 1156 cM, with an average marker spacing of 3.9 cM and encompasses nearly the whole genome. The average number of crossovers per chromosome per individual is 0.86. Normal recombination over the entire genome occurs in the heterothallic variety, burnettii, contrary to the homothallic variety, bisporus, which showed adaptive genome-wide suppressed recombination. This first comprehensive genetic linkage map for A. bisporus provides foundations for quantitative trait analyses and breeding programme monitoring, as well as genome

Profils métaboliques de pêche: une étude des métabolites primaires et secondaires par RMN-1H et HPLC de deux descendances révèle de profondes variations entre génotypes et la présence de composés inattendus.

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Detection of QTLs controlling major fruit quality components in peach within the European project ISAFRUIT

International audienceISAFRUIT is a European integrated project aimed at increasing fruit consumption with the goal to improve health of the European citizens. One of the objectives of the work package GENFRUIT is to set the genetic basis of fruit quality by mapping the major genes and QTLs involved (Work package 6.1). This is performed on two peach (Prunus persica L. Batsch) and two apricot (Prunus armeniaca L.) progenies. Only results obtained on one of the two peach progenies, the F2 progeny of 207 hybrids issued from the ‘Ferjalou’ Jalousia® x ‘Fantasia’ cross (JxF), will be described in this paper. This progeny is segregating for six Mendelian traits, peach or nectarine (G), flat or round fruit (S), non-acid or acid fruit (D), clingstone or freestone (F), male sterility (Ps), no fruit at maturity (af), as well as for quantitative characters involved in fruit quality. This progeny was evaluated for various characters such as blooming and maturity date, fruit fresh, and dry weight, flesh firmness, juice soluble solid content; pH and acidity. The quantification of the flesh concentration in 15 to 20 major metabolites (glucose, fructose, sucrose, citrate, malate, major amino acids, and some major secondary metabolites) was performed in Bordeaux using proton NMR spectroscopy of polar extracts. Phenolics profiling, using HPLC-DAD, was performed in Avignon. Candidate genes involved in fruit sugar or acid contents and fruit development were bin mapped in the reference map ‘Texas’ x ‘Earlygold’ and in JxF. Preliminary results on QTL detection concerning fruit quality characters are presented. First colocalisations of QTLs with candidate genes were identified. In the future, the colocalisation of QTLs with candidate genes, and the colinearity of QTLs detected on the different populations analyzed in the ISAFRUIT project will be examined

QTL analysis of metabolites involved in fruit quality in Prunus species and co-location with candidate genes in the European Project ISAFRUIT - Preliminary results obtained on P. persica related species

International audienc

ISAFRUIT. Study of the genetic basis of Prunus fruit quality in two peach and two apricot populations

International audienceA European Integrated Project, untitled ‘ISAFRUIT’, has been engaged in January 2006. It deals with the improvement of fruit consumption by the consumers under both objectives: the optimization of the quality of the row products, and the optimization of the cultural practices. The project involves 40 Research Institutes and 20 Companies issued from 14 European countries and two associated countries. Within the whole project, a work package (6.1) is dedicated to the study of the genetics of fruit quality and health properties. It is subdivided in six main tasks, among them two concerning peach and apricot quality attributes have been already engaged: Task 1 – Identification and mapping of candidate genes for fruit quality in saturated maps of peach and apricot. Task 3 – QTLs analysis of fruit quality. Six research laboratories are involved in theses parts of the project based on the analysis of four Prunus progenies of 120 hybrid each, two apricot progenies cultivated in Avignon (Fr) and Bologna (It), and two peach progenies cultivated in Avignon and Bordeaux (Fr). Fruit quality characterization is based on (i) physical measurements (fruit weight, colour, firmness), (ii) biochemical measurements (refractometric index, titratable acidity) and (iii) on a fine metabolic profiling based on 1H RMN 1D, targeting the major metabolites, associated with a phenolic compounds characterization by HPLC. The related datasets will be joined with the genetic map under saturation for localising the associated QTLs. A particular attention will be paid to the co-linearity between species

Profils métaboliques de la pêche et de l’abricot pour l’étude des bases génétiques de la qualité des fruits de Prunus dans le projet européen Isafruit

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ISAFRUIT IP project. Genetic and molecular bases of peach and apricot fruit quality

International audienc

Study of the genetic basis of Prunus fruit quality in 2 peach and 2 apricot populations

International audienc