Développement de marqueurs microsatellites chez les agrumes

National audienc

Nuclear microsatellite markers for the date palm (Phoenix dactylifera L.): characterization and utility across the genus Phoenix and in other palm genera.

A (GA)n microsatellite-enriched library was constructed and 16 nuclear simple sequence repeat (SSR) loci were characterized in Phoenix dactylifera. Across-taxa amplification and genotyping tests showed the utility of most SSR markers in 11 other Phoenix species and the transferability of some of them in Elaeis guineensis, 11 species of Pritchardia, Pritchardiopsis jeanneneyi and six species of Astrocaryum. The first to be published for P. dactylifera, these new SSR resources are available for cultivar identification, pedigree analysis, germplasm diversity as well as genetic mapping studie

A new set of microsatellite markers for the peach palm (Bactris gasipaes Kunth): characterization and across-taxa utility within the tribe Cocoeae.

A (GA)n microsatellite-enriched library was constructed and a new set of 18 nuclear simple sequence repeat loci was isolated in Bactris gasipaes var. gasipaes. The loci were found to be highly variable in the target species and readily transferable to related Bactris species as well as to the Astrocaryum and Elaeis genera of the same Cocoeae tribe. These microsatellite resources are made available to study the genetic diversity and gene flow within the Bactris complex for a better understanding of the domestication process of the peach palm and for further Cocoeae genetic

Fingerprinting data musa accessions with SSR

561 accessions fingerprinted at CIRAD with 22 SSRs

Comparative linkage mapping in three guava mapping populations and construction of an integrated reference map in guava

Integrated parental linkage maps have been constructed in three guava mapping populations ('Enana' × "N", 'Enana' × 'Suprema Roja' and 'Enana' × 'Belic L-207') based on AFLP and SSR markers. Between 102 and 119 AFLP primer combinations (PCs) were analysed in each population, generating between 684 and 1163 segregating AFLP fragments. The distribution of parent-specific and common markers indicated that 'Enana' is less heterozygous than the other parents and that all parents share a considerable gene pool. In addition, between 28 and 171 SSR PCs were analysed for linkage mapping in these populations. Initially parent specific linked fragments were arranged into linkage groups. In all mapping population, 11 linkage groups (LGs) corresponding to the 11 chromosomes of the haploid guava genome were obtained for each parent. Based on the available SSR markers, combined parental linkage maps of each mapping population were produced using as anchor points allelic SSR fragments and common AFLP fragments. These integrated maps contain between 408 and 850 markers and have lengths of 1885 to 2179 cM, respectively. Average linkage group lengths in these maps vary between 160 and 198 cM and contain on average between 37 and 77 markers. Several identical SSR markers were mapped in various progenies, and potential associations of linkage groups from different populations were detected. In the future, the number of common SSR markers has to be increased in order to achieve full alignment of all individual linkage maps into a high-density reference molecular linkage map of guava

New microsatellite markers developed from an enriched microsatellite common bean library Novos marcadores microssatélites desenvolvidos a partir de uma biblioteca genômica enriquecida em feijão-comum

The objective of this work was to develop new microsatellite markers in common bean. Ninety nine new microsatelitte loci were developed from a microsatellite enriched library for (CT)8 and (GT)8 motifs, from CAL-143 line. The majority of microsatellite sequences (51%) was related to cellular metabolism. The remaining sequences were associated to transcription functions. Only 17.2% of the sequences presented some level of similarity with other plant species genes.<br>O objetivo deste trabalho foi desenvolver novos marcadores microssatélites para feijão-comum. Noventa e nove novos locos de microssatélites foram desenvolvidos a partir de uma biblioteca enriquecida com motivos (CT)8 e (GT)8, proveniente da linhagem CAL-143. A maioria dos microssatélites (51%) esteve relacionada ao metabolismo celular. As demais seqüências estiveram associadas a funções de transcrição. Apenas 17,2% das seqüências apresentaram alguma semelhança com genes de outras espécies

Genetic diversity of the greater yam (Dioscorea alata L.) and relatedness to D. nummularia Lam. and D. transversa Br. as revealed with AFLP markers

UMR DAPInternational audienceAmplified fragment length polymorphism markers were used to assess the genetic relatedness between Dioscorea alata and nine other edible Dioscorea. These species include D. abyssinica Hoch., D. bulbifera L., D. cayenensis-rotundata Lamk. et Poir., D. esculenta Burk., D. nummularia Lam., D. pentaphylla L., D. persimilis Prain. et Burk., D. transversa Br. and D. trifida L. Four successive studies were conducted with emphasis on the genetic relationship within D. alata and among species of the Enantiophyllum section from Vanuatu. Study 1 was carried out to select a set of polymorphic primer pairs using 11 combinations and eight species belonging to five distinct sections. The four most polymorphic primer pairs were used in study 2 among six species of the Enantiophyllum section. Study 3 focussed mainly on the genetic relationship among 83 accessions of D. alata, mostly from Vanuatu (78 acc.) but also from Benin, Guadeloupe, New Caledonia and Vietnam. The ploidy level of 53 accessions was determined and results indicated the presence of tetraploid, hexaploid and octoploid cultivars. Study 4, included 35 accessions of D. alata, D. nummularia and D. transversa and was conducted using two primer pairs to verify the taxonomical identity of thecultivars ‘langlang’, ‘maro’ and ‘netsar’ from Vanuatu. The overall results indicated that each accession can be fingerprinted uniquely with AFLP. D. alata is an heterogeneous species which shares a common genetic background with D. nummularia and ‘langlang’, ‘maro’ and ‘netsar’. UPGMA cluster analysis revealed the existence of three major groups of genotypes within D. alata, each assembling accessions from distant geographical origins and different ploidy levels. The analysis also revealed that ‘langlang’, ‘maro’ and ‘netsar’ clustered together with the cultivar ‘wael’ (D. transversa) from New Caledonia. Results are discussed in the pape