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Sweet cherries (Prunus avium L.) are highly appreciated fruits for their taste, color, nutritional value, and beneficial health effects. In this work, seven new cultivars of sweet cherry were investigated for their main quality traits and nutraceutical value. The phytochemical profile of three classes of phenolic compounds and the antioxidant activity of the new cultivars were investigated through high-performance liquid chromatography with diode array detection (HPLC-DAD) and spectrophotometric assays, respectively, and compared with those of commonly commercialized cultivars. Cyanidine-3-O-rutinoside was the main anthocyanin in all genotypes, and its levels in some new cultivars were about three-fold higher than in commercial ones. The ORAC-assayed antioxidant capacity was positively correlated with the total anthocyanin index. The nutraceutical value of the new cultivars was investigated in terms of antioxidant/neuroprotective capacity in neuron-like SH-SY5Y cells. Results demonstrated that the new cultivars were more effective in counteracting oxidative stress and were also able to upregulate brain-derived neurotrophic factor (BDNF), a pro-survival neurotrophin, suggesting their potential pleiotropic role in counteracting neurodegenerations.

Low rooting and survival in the acclimatization phase are among the main factors that can negatively affect in vitro propagation of apricot. We investigated: (a) the effect of different jar closure types [hermetic (H), cotton plugs (C) and polyvinyl chloride (PVC) sealing] on C 2 H 4 and CO 2 accumulation, and in vitro rooting of apricot shoots, cv. San Castrese, Boreale and Vitillo; (b) plantlet behavior after transfer ex vitro . ‘San Castrese’ showed the highest rooting aptitude, regardless of the jar closure type. The H closure strongly increased C 2 H 4 (up to 567 ηmol mol −1 in ‘San Castrese’) and CO 2 (to a mean of 85 mmol mol −1 ) accumulation inside jars, without affecting in vitro rooting percentages; however, it significantly reduced root number in comparison to PVC. The H closure also lowered survival rates in the acclimatization phase, especially compared to C, and caused reduced root growth in ‘Boreale’ and ‘Vitillo’ if compared to PVC and C, respectively. Moreover, plantlets from H were generally shorter.

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; An integrated consensus genetic map for apple was constructed on the basis of segregation data from four genetically connected crosses (C1 = Discovery x TN10-8, C2 = Fiesta x Discovery, C3 = Discovery x Prima, C4 = Durello di Forli x Fiesta) with a total of 676 individuals using CarthaGene(R) software. First, integrated female-male maps were built for each population using common female-male simple sequence repeat markers (SSRs). Then, common SSRs over populations were used for the consensus map integration. The integrated consensus map consists of 1,046 markers, of which 159 are SSR markers, distributed over 17 linkage groups reflecting the basic chromosome number of apple. The total length of the integrated consensus map was 1,032 cM with a mean distance between adjacent loci of 1.1 cM. Markers were proportionally distributed over the 17 linkage groups (chi(2) = 16.53, df = 16, p = 0.41). A non-uniform marker distribution was observed within all of the linkage groups (LGs). Clustering of markers at the same position (within a 1-cM window) was observed throughout LGs and consisted predominantly of only two to three linked markers. The four integrated female-male maps showed a very good colinearity in marker order for their common markers, except for only two (CH01h01, CH05g03) and three (CH05a02z, NZ02b01, Lap-1) markers on LG17 and LG15, respectively. This integrated consensus map provides a framework for performing quantitative trait locus (QTL) detection in a multi-population design and evaluating the genetic background effect on QTL expression

Pear scab caused by Venturia pyrina is an economically important disease throughout the world and can cause severe crop loss in susceptible cultivars. The varying range of susceptibility to pear scab in F1 populations has made it possible to identify quantitative trait loci (QTLs). Ninety-five seedlings derived from the cross ‘Abbe Fetel’ (AF) × ‘Max Red Bartlett’ (MRB) were evaluated for scab resistance in greenhouse tests, with 39% being classified as resistant, 33 as moderately susceptible and 28 as highly susceptible. Amplified fragment length polymorphisms (157) and simple sequence repeats (41) were used to construct two maps, one of 908.1 cM (AF) and the other of 879.8 cM (MRB). The analysis of the resistance data collected made it possible to identify two major QTLs on linkage groups 3 and 7 associated with resistance to V. pyrina. Both QTLs explained 88% of the phenotypic variance and the log of odds values were higher than 10, suggesting the involvement of two major genes in pear scab resistance.

The identification of Venturia inaequalis races able to overcome the well-known and widely used Vf-scab resistance gene has instigated the search and characterisation of new sources of resistance in germplasm collections. Various new sources of scab resistance in Italian germplasm were tested to determine their inheritance as part of the EU-D.A.R.E. project. The cultivar ‘Durello di Forlì’ showed a very low scab susceptibility to different Venturia inaequalis inocula under various test conditions. This paper is a report on the preliminary characterisation of this new source of scab resistance identified by a race 6 strain of Venturia inaequalis.

A chromosomal region originating from Malus floribunda 821 confers Vf scab resistance to many isolates of Venturia inaequalis. Twelve DNA markers located in this region were used to scan the equivalent of 31 cM in 98 Malus accessions. This allowed a molecular diagnosis of a source of resistance in apple germplasm with the aid of pedigree information, and in the context of a limited marker survey representing other chromosomes. At least five marker alleles were present in all scab-resistant breeding selections or varieties arising from M. floribunda. The validity of findings based on RAPD markers was confirmed with SCAR assays and Southern-hybridisation experiments. The order of markers determined in previous mapping studies was confirmed and sets of recombinants identified that establish reliable fine-mapping orders within 0.7 cM of the resistance locus. None of the marker alleles were present in the accessions that are either susceptible or possess weak polygenic resistance to scab. The presence of some alleles corresponding to those present at least 5.3 cM from Vf in M. floribunda was detected in some accessions. Other major sources of scab resistance do not appear to possess alleles in common with the Vf region, which will simplify future allelism tests. The results are discussed in the context of the introgression of resistance loci together with marker-assisted selection. The use of breeding pedigrees to assist in fine-scale mapping and map-based cloning is discussed.

Apple scab, caused by the fungus Venturia inaequalis, is the major production constraint in temperate zones with humid springs. Normally, its control relies on frequent and regular fungicide applications. Because this control strategy has come under increasing criticism, major efforts are being directed toward the breeding of scab-resistant ap- ple cultivars. Modern apple breeding programs include the use of molecular markers, making it possible to combine several different scab-resistance genes in 1 apple cultivar (pyramiding) and to speed up the breeding process. The apple scab-resistance gene Vb is derived from the Siberian crab apple 'Hansen's baccata #2', and is 1 of the 6 ''historical'' major apple scab-resistance genes (Vf, Va, Vr, Vbj, Vm, and Vb). Molecular markers have been published for all these genes, except Vr. In testcross experiments conducted in the 1960s, it was reported that Vb segregated independently from 3 other major resistance genes, including Vf. Recently, however, Vb and Vf have both been mapped on linkage group 1, a result that contrasts with the findings from former testcross experiments. In this study, simple sequence re- peat (SSR) markers were used to identify the precise position of Vb in a cross of 'Golden Delicious' (vbvb) and 'Hansen's baccata #2' (Vbvb). A genome scanning approach, a fast method already used to map apple scab-resistance genes Vr2 and Vm, was used, and the Vb locus was identified on linkage group 12, between the SSR markers Hi02d05 and Hi07f01. This finding confirms the independent segregation of Vb from Vf. With the identification of SSR markers linked to Vb, another major apple scab-resistance gene has become available; breeders can use it to de- velop durable resistant cultivars with several different resistance genes. Resume´ : La tavelure du pommier, causee par le champignon Venturia inaequalis, constitue la principale contrainte ala production dans les zones temperees aux printemps humides. Habituellement, la lutte repose sur des pulverisations regulie `- res et frequentes avec de fongicides. Une telle methode etant de plus en plus critiquee, des efforts importants sont diriges du cotede la selection de cultivars resistants ala tavelure. Les programmes modernes d'amelioration genetique du pom- mier incluent l'emploi de marqueurs moleculaires, rendant ainsi possible la combinaison (pyramidage) de plusieurs genes de resistance au sein d'un seul cultivar et accelerant le processus de selection. Le gene de resistance Vb est issu du pom- metier de Siberie 'Hansen's baccata #2' et il est un de six genes majeurs « historiques » de resistance a la tavelure (Vf, Va, Vr, Vbj, Vm et Vb). Des marqueurs moleculaires ont eterapportes pour tous ces genes sauf Vr. Lors de croisements test effectues dans les annees '60, il avait eteconclu que Vb affichait une segregation independante de trois autres genes majeurs dont Vf .R ecemment, cependant, Vf et Vb ont tous deux eteassignes au groupe de liaison 1, un resultat qui va a ` l'encontre des resultats des croisements test. Dans ce travail, des microsatellites (SSR) ont eteemployes pour definir la po- sition precise du locus Vb au sein d'un croisement entre 'Golden Delicious' (vbvb) et 'Hansen's baccata #2' (Vbvb). En faisant appel a une approche de balayage genomique (GSA; « Genome Scanning Approach »), une metode rapide dejaem- ployee pour realiser la cartographie des genes Vr2 et Vm ,aeteutiliseet il en est ressorti que le locus Vb est situesur le groupe 12 entre les microsatellites Hi02d05 et Hi07f01. Ce resultat confirme la segregation independante des locus Vb et Vf. Avec l'identification de marqueurs pour le gene Vb, un autre gene majeur de resistance a la tavelure est disponible pour les selectionneurs afin de developper des cultivars possedant une resistance durable fondee sur plusieurs genes de re ´- sistance differents. Mots cles : Venturia inaequalis, Malus x domestica, SSR, GSA, microsatellites, cartographie genetique. (Traduit par la Redaction)

For all known major apple scab resistance genes except Vr, molecular markers have been published. However, the precise position of some of these genes, in the apple genome, remains to be identified. Knowledge about the relative position of apple scab resistance genes is necessary to preliminarily evaluate the probability of success of their pyramidization. Pyramidization of different resistance genes into the same genotype is a reliable way to create cultivars with durable apple scab resistance. Applying the genome scanning approach (GSA), we identified the linkage group of the scab resistance gene Vm, derived from Malus micromalus, and we found a new molecular marker tightly associated with the gene. The simple sequence repeat Hi07h02, previously mapped on linkage group 17, cosegregates with the Vm gene (no recombinants in the 95 plants tested). The already published sequence-characterized amplified region Vm marker OPB12687was found to be linked at about 5 cM from the resistance gene and, therefore, this marker also maps on linkage group 17 of apple. This is the first report of the discovery of a major apple scab resistance gene on linkage group 17. The advantages of using GSA for the identification of molecular markers for qualitative traits are discussed.Key words: Malus, Venturia inaequalis, mapping, simple sequence repeat.

In the frame of the D.A.R.E. project, five mapping populations have been studied for partial scab resistance against several races of Venturia inaequalis. A main objective was to identify QTLs (quantitative traits loci) with broad spectrum of resistance towards a wide range of strains of the fungus. Genetic markers (mainly SSR and AFLP) were tested on each population and genetic maps were constructed for both parents of each population. Meanwhile, pathological tests with several isolates of different races of V. inaequalis were performed. Four major genomic regions appear to be involved in scab resistance: they are located on linkage groups (LG) LG-1, LG-2, LG-11, and LG-17. Some other linkage groups carry either QTLs or major resistance genes that are isolate specific: a QTL on LG-5, Vd on LG-10, and Vg on LG-12. The QTL region located on LG-17 clearly exhibited the widest spectrum of resistance

Low rooting, and survival in the acclimatization phase are among the main factors that can negatively affect in vitro propagation of apricot. We investigated: a) the effect of different jar closure types [hermetic (H), cotton plugs (C) and polyvinyl chloride (PVC) sealing] on C2H4 and CO2 accumulation, and in vitro rooting of apricot shoots, cv. San Castrese, Boreale and Vitillo; b) plantlet behaviour after transfer ex vitro. ‘San Castrese’ showed the highest rooting aptitude, regardless of the jar closure type. The H closure strongly increased C2H4 (up to 567 ηmol mol-1 in ‘San Castrese’) and CO2 (to a mean of 85 mmol mol-1) accumulation inside jars, without affecting in-vitro rooting percentages; however, it significantly reduced root number in comparison to PVC. The H closure also lowered survival rates in the acclimatization phase, especially compared to C, and caused reduced root growth in ‘Boreale’ and ‘Vitillo’ if compared to PVC and C, respectively. Moreover, plantlets from H were generally shorter.