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International audience; The French apricot production is located in the southeastern part of the country with a focused zone in the Rhone valley and close to the Mediterranean Sea. The north of Rhone valley is characterized by a continental climate while the southern region (Rhone valley and Mediterranean area) is characterized by a typical Mediterranean climate. Due to economic and adaptation constraints the apricot fruit production depends on the development of a specific range of cultivars in the different areas of cultivation. In order to enlarge the panel of, a breeding program is developed at a national level in France with the participation of CEP INNOVATION, CENTREX and INRA. The main goals of the breeding program are: the elaboration of cultivars suitable for a durable production (including resistance to pests and diseases), production regularity (including self-fertility and quality of the flowers), and fruit quality (including taste, attractiveness, and suitability for the transport). Out of a first evaluation stage in nursery, based on a MAS approach targeted onto sharka susceptibility and Self-fertility, the agronomical evaluation is performed in orchard and followed by an evaluation of the pre-selections after grafting in the 3 main areas of cultivation for integrating the adaptability. Then the ‘elite’ agronomic and commercial assessments are conducted in small orchards. The main results issued from this program are here presented with 10 blushy and purple-red cultivars including five PPV resistant ‘Aramis®’ cultivars.

International audience; ILLIAD is a French national project in which food-chain sustainability is being evaluated on four products ( wheat, rice, peach and apricot). For apricot, two difficulties for French production have been identified: i) the high cost of manpower in this culture and ii) fruit processors' dependence on surplus fruits from fresh consumption. This leads to very high variability in supply, price and quality from year to year. In this context, one solution might be dedicated orchards for processing industries. At first, cultivars well adapted to processing and with a low demand for inputs were screened for their behavior in mechanical harvest. Mechanical harvest was carried out using tree shaking ( at 40 cm from the ground) and collection on a fabric screen. Results obtained over 2 years on more than 15 cultivars and in two production areas are presented. The low mechanical damage observed just after harvesting or after 7 days of storage for a few cultivars and the possibility of optimizing shaking parameters according to agronomic and physiologic criteria ( fruit falling, maturity heterogeneity, etc.) confirm the suitability of mechanical harvesting and the opportunity to create dedicated orchards.

In autumn 2001, severe yellowing symptoms were observed on greenhouse-grown cucumbers near Perpignan (southern France). Leaf samples were collected from two sites where plants displayed symptoms ranging from limited yellowing of the older leaves to severe, complete yellowing of the whole plant. Cucurbit aphid-borne yellows virus, a polerovirus that causes similar symptoms was not detected in doubleantibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) using a specific antiserum. Total RNA was extracted from fresh leaf tissues and used in reverse transcription-polymerase chain reaction (1) with primers specific for two whitefly-borne viruses also inducing yellows and occurring in the Mediterranean basin (1): Beet pseudo yellows virus (BPYV, genus Closterovirus) transmitted by Trialeurodes vaporariorum (West.) and Cucurbit yellow stunting disorder virus (CYSDV, genus Crinivirus) transmitted by Bemisia tabaci (Genn.). No BPYV was detected in this survey, but CYSDV was present in all samples. In subsequent surveys conducted in the spring and summer of 2002, BPYV and CYSDV were detected, sometimes in mixed infections, in samples collected from the same region. The complete CYSDV coat protein gene was amplified by PCR using specific primers (2), yielding the expected-size fragment of 756 bp. The French isolate (GenBank Accession No. AY204220) shared 99.6 to 100% nucleotide sequence identity in the sequenced CP fragments (700 nt) with isolates of the most common, highly homogenous subgroup of CYSDV that has emerged recently in the Middle East, southwestern Europe (Spain and Portugal), United States, and Morocco (2). To our knowledge, this is the first report of CYSDV in France and it shows the threat represented by the current emergence of B. tabaci-transmitted viruses. References: (1) I. C. Livieratos et al. Plant Pathol. 47:362, 1998. (2) L. Rubio et al. J. Gen. Virol. 82:929, 2001.

International audience; Complete genomic sequences of Artichoke latent virus (ArLV) have been obtained by classical or high-throughput sequencing for an ArLV isolate from Italy (ITBr05) and for two isolates from France (FR37 and FR50). The genome is 8,278 to 8,291 nucleotides long and has a genomic organization comparable with that of Chinese yam necrotic mosaic virus (CYNMV), the only macluravirus fully sequenced to date. The cleavage sites of the viral polyprotein have been tentatively identified by comparison with CYNMV, confirming that macluraviruses are characterized by the absence of a P1 protein, a shorter and N-terminally truncated coat protein (CP). Sequence comparisons firmly place ArLV within the genus Macluravirus, and confirm previous results suggesting that Ranunculus latent virus (RALV), a previously described Macluravirus sp., is very closely related to ArLV. Serological relationships and comparisons of the CP gene and of the partial RaLV sequence available all indicate that RaLV should not be considered as a distinct species but as a strain of ArLV. The results obtained also suggest that the spectrum of currently used ArLV-specific molecular hybridization or polymerase chain reaction detection assays should be improved to cover all isolates and strains in the ArLV species.

The French apricot production is located in the South-Eastern part of the country and focused both in the Rhone valley and close to the Mediterranean Sea. The north of the Rhone valley is characterized by a continental climate while the southern region (Rhone valley and Mediterranean area) is under warm typical Mediterranean climate. Obviously apricot fruit production depends on a specific panel of cultivars in each area of cultivation due to economic and adaptation constraints. In order to enlarge the panel of cultivars to be developed by the growers in each region an integrated breeding program is developed at a national level in France with the participation of INRA, CENTREX and CEP INNOVATION. The main goals of the breeding program are: the elaboration of cultivars suitable for a durable production (including resistance to pests and disease), production regularity (including self-fertility and quality of the flowers), and fruit quality (including taste, attractiveness, and suitability for the transport). The evaluation phase is organized in the 3 main areas of production (Perpignan, Nimes, Valence) and follows 3 complementary evaluation stages (i) observation of the hybrid on its own roots; (ii) evaluation of the best hybrids after grafting in the 3 main areas; (iii) assessment of the agronomic and commercial interest of the 'elite' accessions in small orchards. The main results issued from this program are presented: 8 registered cultivars, 4 new selections under registration, and the first PPV resistant cultivar 'Aramis' ® 'Shamade'.

International audience

International audience; French apricot production is located in the south-eastern part of the country, with a focused zone in the Rhone valley and close to the Mediterranean Sea. The north of the Rhone valley is characterized by a continental climate, while the southern region ( Rhone valley and Mediterranean area) is under a warm, typically Mediterranean climate. Obviously, apricot fruit production depends on the development of a specific panel of cultivars in each area of cultivation because of economic and adaptation constraints. In order to enlarge the panel of cultivars for growers of each region, an integrated breeding program has been developed at a national level in France with the participation of INRA, Centrex and CEP Innovation. The main goals of the breeding program are: the elaboration of cultivars suitable for durable production ( including resistance to pests and diseases), production regularity ( including self-fertility and quality of the flowers), and fruit quality ( including taste, attractiveness, and suitability for transport). The evaluation phase is organized in the three main French areas of production ( Perpignan, Nimes and Valence) with three complementary evaluation stages: ( i) observation of hybrids on their own roots ( ii) evaluation of pre-selections after grafting in the three main areas, and ( iii) 'elite' agronomic and commercial assessments in small orchards. A tough diagnosis, that includes biological, serological and molecular analysis, is conducted in parallel for assessing resistance to Plum pox virus ( PPV). The main results issued from this program are presented here, with 10 cultivars, including PPV-resistant Aramis (R) cultivars.

International audience

International audience

In June 2008, tomato (Solanum lycopersicum L.) plants cv. Fer De Lance (De Ruiter Seeds, Bergschenhoek, the Netherlands) grown in greenhouses near Perpignan (southern France) showed growth reduction and necrotic lesions on fruits, stems, and basal parts of the leaves. Tomato torrado virus (ToTV) was suspected on the basis of symptoms and its recent description in Spain (4). Primer set A (3), designed to ToTV RNA-2, was used for reverse transcription (RT)-PCR experiments on RNA extracted from four infected plants and allowed the amplification of a 493-bp fragment. No amplification was observed from healthy plant extracts. The RT-PCR product was directly sequenced (GQ303330) and a BLAST search in GenBank revealed 99.8- and 99.5%-nt identity with Polish (EU563947) and Spanish type strain (DQ388880) isolates of ToTV, respectively. Double-antibody sandwich-ELISA tests were conducted on these four samples to check for the presence of other viruses commonly found in tomato crops in France. Tomato spotted wilt virus, Parietaria mottle virus, Cucumber mosaic virus, Tomato mosaic virus, and Potato virus Y were not detected but Pepino mosaic virus (PepMV) was detected in all samples. ToTV was mechanically transmitted to Physalis floridana but PepMV was not. This plant was used to inoculate healthy tomatoes that served as a ToTV source for further experiments. Mechanical inoculation to test plants showed that Nicotiana benthamiana, N. clevelandii, N. debneyi, N. glutinosa, Capsicum annuum, Solanum melongena, and some tomato cultivars (including Fer De Lance), in which typical necrotic symptoms were observed, were systemically infected by the virus. Isometric particles ~28 nm in diameter were observed by electron microscopy in crude extracts of infected plants negatively stained with 1% ammonium molybdate, pH 7. To confirm ToTV identification, whitefly transmission experiments were performed with Trialeurodes vaporariorum and Bemisia tabaci. Adult whiteflies were placed in cages with infected tomato plants for 1-, 24-, or 48-h acquisition access periods (AAP) before transferring them by groups of ~50 on susceptible tomato plantlets placed under small containers (six plants per AAP). Forty-eight hours later, plants were treated with an insecticide and transferred to an insect-proof containment growth room. Ten days later, RNA preparation from all plants was tested by RT-PCR for the presence of ToTV. No transmission was observed with a 1-h AAP. With a 24-h AAP, transmission to four of six test plants was observed with both whitefly species, while at 48 h, AAP transmission to three and four plants of six was observed with T. vaporariorum and B. tabaci, respectively. Noninoculated control plants were all negative by RT-PCR. These experiments confirm T. vaporariorum and B. tabaci as natural vectors of ToTV as previously described (1,2). ToTV has been already reported in Spain, Poland, Hungary, and Australia, but to our knowledge, this is the first report of ToTV in France. Our detection of ToTV in April 2009 from the same area revealed 7 positive tomato plants of 17 tested. This observation suggests the persistence of the disease in the Perpignan Region. References: (1) K. Amari et al. Plant Dis. 92:1139, 2008. (2) H. Pospieszny et al. Plant Dis. 91:1364, 2007 (3) J. Van der Heuvel et al. Plant Virus Designated Tomato Torrado Virus. Online publication. World Intellectual Property Organization WO/2006/085749, 2006. (4) M. Verbeek et al. Arch. Virol. 152:881, 2007.