Evaluer la sélection génomique au sein de croisements bi-parentaux d’espèces pérennes fruitières génotypés par séquençage : point d’étape du projet FruitSelGen

Poste

Parentage of grapevine rootstock 'Fercal' finally elucidated

International audienceUsing a set of 20 microsatellite markers, 'B.C. n degrees 1B' (mother) and '31 Richter' (father) were demonstrated to be the true parents of 'Fercal' rootstock. '333 Ecole de Montpellier' was definitively excluded as the putative father. 'B.C. n degrees 1A' and 'B.C. n degrees 1B' were shown to be distinct genotypes. 'Ugni blanc', and not 'Colombard', was discovered to be the Pais vinifera father of 'B.C. n degrees 1B'

Development and characterization of a large set of microsatellite markers in grapevine (Vitis vinifera L.) suitable for multiplex PCR

International audienceDespite their numerous advantages, the use of microsatellites as genetic markers could be limited because of the low number of loci that can be simultaneously analysed per experiment. To increase the information per simple sequence repeat (SSR) assay in the grapevine, we developed a large set of new markers suitable for multiplexing and multi-loading. We produced microsatellite motif-enriched genomic libraries containing preferentially large size inserts which allowed us to design primers generating a wide range of allele sizes in a very standard and unique PCR condition. Three hundred and fifty clones were sequenced and 190 of them (54%) contained microsatellite motifs with suitable flanking regions for primer design. We developed 169 new SSR markers giving suitable signal with fluorescent-based DNA detection. The total number of alleles detected varied from 1 to 8 per locus with an average of 3.5 and the mean expected heterozygosity was 0.544 (range: 0 0.86). Sixty-eight loci (40%) were perfect types, 73 (43%) were imperfect and 28 (17%) were compound or imperfect-compound. The number of alleles generated by perfect and imperfect type loci was positively correlated to the length of the microsatellite motif. Forty-six multiplex sets based on 125 selected loci were developed. Considering their allele size range, up to four PCR multiplex were pooled together for multi-loading. The 169 SSR loci developed in this study represent a new and informative set of markers easy to combine for multiplexing and multi-loading according to the needs of any user and suitable for large scale genetic analyses in grapevine

Resistance to sharka in Stone Fruit trees : Genetic and genomic technologies for new breeding strategies

Resistance to sharka in Stone Fruit trees : Genetic and genomic technologies for new breeding strategies. 9. International Rosaceae Genomics Conferenc

Etude du déterminisme génétique de diverses sources de résistance de la vigne au mildiou

National audienc

Développement de marqueurs moléculaires pour étudier la variabilité et la génétique des populations de Plasmopara viticola, agent du mildiou de la vigne

International audienc

Genetic diversity and population structure analyses in the Alpine plum (Prunus brigantina Vill.) confirm its affiliation to the Armeniaca section

In-depth characterization of the genetic diversity and population structure of wild relatives is of paramount importance for genetic improvement and biodiversity conservation, and is particularly crucial when the wild relatives of crops are endangered. In this study, we sampled the Alpine plum (Briançon apricot) Prunus brigantina Vill. across its natural distribution in the French Alps, where its populations are severely fragmented and its population size strongly impacted by humans. We analysed 71 wild P. brigantina samples with 24 nuclear simple sequence repeat (microsatellite) markers and studied their genetic diversity and population structure, with the aim to inform in situ conservation measures and build a core collection for long-term ex situ conservation. We also examined the genetic relationships of P. brigantina with other species in the Prunophora subgenus, encompassing the Prunus (Eurasian plums), Prunocerasus (North American plums) and Armeniaca (apricots) sections, to check its current taxonomy. We detected a moderate genetic diversity in P. brigantina and a Bayesian model–based clustering approach revealed the existence of three genetically differentiated clusters, endemic to three geographical regions in the Alps, which will be important for in situ conservation measures. Based on genetic diversity and population structure analyses, a subset of 36 accessions were selected for ex situ conservation in a core collection that encompasses the whole detected P. brigantina allelic diversity. Using a dataset of cultivated apricots and wild cherry plums (P. cerasifera) genotyped with the same markers, we detected gene flow neither with European P. armeniaca cultivars nor with diploid plums. Similar to previous studies, dendrograms and networks placed P. brigantina closer to the Armeniaca section than to the Prunus section. Our results thus confirm the classification of P. brigantina within the Armeniaca section; it also illustrates the importance of the sampling size and design in phylogenetic studies.ADAPTATION DES CULTURES FRUITIÈRES AU CHANGEMENT CLIMATIQUE DANS LE BASSIN MÉDITERRANÉE

Genetic diversity and population structure analyses in the Alpine plum ( Prunus brigantina Vill.) confirm its affiliation to the Armeniaca section

In-depth characterization of the genetic diversity and population structure of wild relatives of crops is of paramount importance for genetic improvement and biodiversity conservation, and is particularly crucial when the wild relatives of crops are endangered. In this study, we therefore sampled the Alpine plum (Briançon apricot) Prunus brigantina Vill. across its natural distribution in the French Alps, where its populations are severely fragmented and its population size strongly impacted by humans. We analysed 71 wild P. brigantina samples with 34 nuclear markers and studied their genetic diversity and population structure, with the aim to inform in situ conservation measures and build a core collection for long-term ex-situ conservation. We also examined the genetic relationships of P. brigantina with other species in the Prunophora subgenus, encompassing the Prunus (Eurasian plums), Prunocerasus (North-American plums) and Armeniaca (apricots) sections, to check its current taxonomy. We detected a moderate genetic diversity in P. brigantina and a Bayesian model-based clustering approach revealed the existence of three genetically differentiated clusters, endemic to three geographical regions in the Alps, which will be important for in situ conservation measures. Based on genetic diversity and population structure analyses, a subset of 36 accessions were selected for ex-situ conservation in a core collection that encompasses the whole detected P. brigantina allelic diversity. Using a dataset of cultivated apricots and wild cherry plums ( P. cerasifera ) genotyped with the same markers, we detected gene flow neither with European P. armeniaca cultivars nor with diploid plums. In contrast with previous studies, dendrograms and networks placed P. brigantina closer to Armeniaca species than to Prunus species. Our results thus confirm the classification of P. brigantina within the Armeniaca section; it also illustrates the importance of the sampling size and design in phylogenetic studies