Nine polymorphic microsatellite markers were isolated from Tecia solanivora, one of the most serious pests of potato tubers in Central and South America. As found in other studies of Lepidoptera, development of microsatellites is a difficult task: in our case, despite the large number of clones sequenced (796), of which 70 were unique, only nine loci were found to be both variable, and in Hardy-Weinberg equilibrium, No null alleles were detected. The loci were tested in three other co-occurring Gelechiidae species, one of which was variable. These loci will be used to provide a greater understanding of the genetic changes occurring during the invasive process in this species.

Ten microsatellites were isolated and characterized from a partial genomic library of Rhodnius prolixus, the principal Chagas disease vector in Venezuela, Colombia and Central America. These polymorphic molecular markers could be particularly useful in Chagas disease control initiatives. A wider applicability of the primer-pairs isolated was shown, from 6 to 10 loci being amplifiable in five out of the ten Rhodnius species tested, namely R. domesticus, R. nasutus, R. neglectus, R. neivai and R. robustus. Interestingly, all the loci were amplified in the latter. These markers may be of interest to trace the colonization of human dwellings from triatomine sylvatic populations in order to better define epidemiological risk patterns.

We report the characterization of 28 polymorphic microsatellite markers in Linum usitatissimum that allow distinguishing almost all cultivars of both flax and linseed. Polymorphism was low, ranging from two to 10 alleles per locus in the 93 cultivars screened. Linkage disequilibrium was found at about a third of the pairs of loci likely due to self-fertilization and strong selection by breeders. We tested these loci for cross-amplification in nine additional species of Linum and found that three species amplified a majority of loci.

Varroa destructor, now a major pest of the Western honeybee, Apis mellifera, switched from its original host, the Eastern honeybee, A. cerana, ca. 50 years ago. So far, only two out of several known mitochondrial haplotypes of V. destructor have been found to be capable of reproducing on A. mellifera (Korea and Japan). These haplotypes are associated in almost complete cytonuclear disequilibrium to diagnostic alleles at 11 microsatellite loci. By contrast, microsatellite polymorphism within each type is virtually absent, because of a severe bottleneck at the time of host change. Accordingly, 12 mitochondrial sequences of 5185 nucleotides displayed 0.40% of nucleotide divergence between haplotypes and no intra haplotype variation. Hence, each type has a quasi-clonal structure. The nascent intratype variability is subsequent to the clone formation 50 years ago: in both types the variant alleles differ from the most common by one (in 10 cases), two (five cases) or three (one case) repeated motifs. In addition to individuals of the two 'pure' types, five F1 hybrids and 19 recombinant individuals (Japan alleles introgressed into the Korea genetic background) were detected. The existence of F1 and recombinant individuals in admixed populations requires that double infestations of honeybee cells occur in a high proportion but the persistence of pure types suggests a post-zygotic isolation between the two clones.

We report the development of five microsatellite markers for the invasive North American native plant Ambrosia artemisiifolia (Asteraceae). An enrichment protocol was used to isolate microsatellite loci and polymorphism. was explored with samples from 16 natural populations collected in the native range, across North America, and in an invaded area along the Rhone Valley in France. In these areas, we found a high level of polymorphism within population and significant heterozygote deficiencies.

A linkage map for the honeybee (Apis mellifera) was constructed mainly from the progeny of two hybrid queens (A. m. ligustica × A. m. mellifera). A total of 541 loci were mapped; 474 were microsatellite loci; a few were additional bands produced during PCRs, one of the two rDNA loci (using ITS), the MDH locus, and three sex-linked markers (Q and FB loci and one RAPD band). Twenty-four linkage groups were estimated of which 5 were minute (between 7.1 and 22.8 cM) and 19 were major groups (>76.5 cM). The number of major linkage groups exceeded by three the number of chromosomes of the complement (n = 16). The sum of the lengths of all linkage groups amounts to 4061 cM to which must be added at least 320 cM to link groups in excess, making a total of at least 4381 cM. The length of the largest linkage group I was 630 cM. The average density of markers was 7.5 cM and the average resolution was about one marker every 300 kb. For most of the large groups, the centromeric region was determined genetically, as described in Baudry et al. (2004, accompanying article in this issue), using half-tetrad analysis of thelytokous parthenogens in which diploid restoration occurs through central fusion. Several cases of segregation distortion that appreared to result from deleterious recessives were discovered. A low positive interference was also detected.

We report the development of seven microsatellite markers in the high Andean Asteraceae Chaetanthera pusilla. An enrichment protocol was used to isolate microsatellite loci, and polymorphism was explored with samples from two natural populations collected in the high Andes at La Parva and Valle Nevado (Chile). We found a high level of polymorphism, heterozygote deficiency and strong differentiation among populations. Four of the seven loci successfully cross-amplified in other Chaetanthera species.

While workers of almost all subspecies of honeybee are able to lay only haploid male eggs, Apis mellifera capensis workers are able to produce diploid female eggs by thelytokous parthenogenesis. Cytological analyses have shown that during parthenogenesis, egg diploidy is restored by fusion of the two central meiotic products. This peculiarity of the Cape bee preserves two products of a single meiosis in the daughters and can be used to map centromere positions using half-tetrad analysis. In this study, we use the thelytokous progenies of A. m. capensis workers and a sample of individuals from a naturally occurring A. m. capensis thelytokous clone to map centromere position for most of the linkage groups of the honeybee. We also show that the recombination rate is reduced by >10-fold during the meiosis of A. m. capensis workers. This reduction is restricted to thelytokous parthenogenesis of capensis workers and is not observed in the meiosis of queen within the same subspecies or in arrhenotokous workers of another subspecies. The reduced rate of recombination seems to be associated with negative crossover interference. These results are discussed in relation to evolution of thelytokous parthenogenesis and maintenance of heterozygosity and female sex after thelytoky.

SummaryMicrosatellites are currently considered the most useful genetic markers with wide applications in genomics, quantitative and population genetics. We present here the structure of the core sequence of 552 microsatellites, together with the sequences of the primers and the length of the sequenced allele. These microsatellites were isolated from several libraries constructed from either fractions of total genomic DNA or from clones of a bacterial artificial chromosome (BAC) library. All 552 loci are polymorphic in the honeybee. Many of them were also successfully amplified in three other species of Apis: A. cerana (58%), A. dorsata (59%) and A. florea (38%). A summary of the variability of 36 loci in the three main evolutionary lineages of A. mellifera is given.

Sixteen microsatellite loci were isolated and characterized for Varroa destructor using two procedures to screen genomic libraries. Together with those previously designed, they provide useful markers for the study of this harmful apicultural pest whose populations on Apis mellifera are poorly variable. Observed variability has been expressed as the number of alleles because heterozygosity is only rarely present. The defined primers have been assayed on another species of the same genus (V. jacobsoni) and almost half of them successfully cross-amplified and revealed polymorphism. These results suggest that the microsatellites isolated here should prove useful for population studies in different Varroa species.

We report the characterization of 12 polymorphic microsatellite markers in the biotrophic fungus Puccinia triticina , the causal agent of leaf rust on wheat. An enrichment protocol was used to isolate microsatellite loci and polymorphism was explored with 15 European isolates. Significant level of cross-amplification (44% of the loci) was found in P. striiformis .

We report the development of 11 microsatellite markers by an enrichment protocol in the ponerine ant Ectatomma tuberculatum. Polymorphism was explored in two colonies collected from Mexico and two colonies from Brazil. From the 11 loci which amplified, seven loci showed intracolonial polymorphism in Mexican colonies and only six loci were variable in populations from Brazil. Observed heterozygosity ranged from 0.18 to 0.84. The other five loci exhibited different alleles between Mexico and Brazil but geographical variability was not investigated further. Cross-amplification was tested in another species of the same Tribe (Gnamptogenys striatula) and one locus was revealed to be polymorphic.

Caryedon serratus feeds on the seeds of four genera of wild Caesalpinioideae. It recently became a major pest of groundnut in Africa. To determine the extent of gene flow and isolation between wild and groundnut-feeding populations, we isolated and characterized 10 microsatellite loci in this species. Polymorphism ranged from three to 15 alleles in the 80 individuals collected in four localities in Senegal on five host plants.

We report the characterization of 12 microsatellite markers in the biotrophic fungus Puccinia striiformis f.sp. tritici , responsible for yellow rust on wheat. An enrichment protocol was used to isolate microsatellite loci, and polymorphism was explored with 96 isolates from natural populations collected from several French and Chinese locations. Eight primers (67%) showed cross-amplification when tested with eight isolates of P. triticina .

We report the development of eight microsatellite markers in the haploid filamentous fungus Fusarium culmorum, a pathogen of numerous cereal crops. An enrichment protocol was used to isolate microsatellite loci, and polymorphism was explored with isolates of Fusarium culmorum and F. graminearum from natural populations collected from several French locations.

Nine microsatellite markers were characterized in the fungus Botrytis cinerea . Genomic DNA sequences from the partial sequencing of 12 000 bacterial artificial chromosome (BAC) clones, were screened by BLAST for various microsatellite motives, and primer pairs were designed. Cross-amplification and polymorphism were assessed on 49 isolates from B. cinerea and two related species, collected from natural populations on several plants and locations.

We report the development of 44 microsatellite markers in three host races of the fungus Microbotryum violaceum, a sexually transmitted disease of the Caryophyllaceae. An enrichment protocol was used to isolate microsatellite loci from three strains, collected, respectively, from the plant species Gypsophila repens, Dianthus sylvestris, and Silene vulgaris. Polymorphism and cross-amplification were explored with 32 isolates of M. violaceum, collected on 12 different plant species in natural populations.

Five microsatellite loci were used to determine paternities in six Apis mellifera colonies headed by naturally mated queens. The last inseminating males were identified by collecting and genotyping the mating sign left in the genital tract of each queen. Significant differences in paternity frequencies were observed between males, but the proportion of worker and queen offspring sired by the last inseminating drone did not differ significantly from those of other drones. Each male kept his rank of precedence for the different cohorts, although the variance in subfamily proportions decreased over time, most notably in the colony displaying the lowest level of polyandry. These results suggest that, if sperm competition exists in the honeybee, it does not significantly increase the fitness of the last inseminating drone. The spermatozoa of the different inseminating drones are not totally mixed before they reach the spermatheca, in particular when only few males mate with the queen. The weak difference in the subfamily proportions observed between queen and worker samples confirms that nepotistic interactions are rare. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.

Molecular EcologyVolume 9, Issue 8 p. 1191-1193 Highly polymorphic microsatellite markers in the landsnail Helix aspersa (Mollusca Gastropoda) A. Guiller, Corresponding Author A. Guiller Laboratoire de Parasitologie Pharmaceutique, CNRS UMR 6553, Faculté des Sciences Pharmaceutiques et Biologiques, 35043 Rennes, France, Annie Guiller. Fax: +02 99 33 68 96; E-mail: [email protected]Search for more papers by this authorJ.-F. Arnaud, J.-F. Arnaud Laboratoire de Parasitologie Pharmaceutique, CNRS UMR 6553, Faculté des Sciences Pharmaceutiques et Biologiques, 35043 Rennes, France, Laboratoire de Zoologie et d'Ecophysiologie, CNRS UMR 6553, Campus de Beaulieu, 35042 Rennes, France,Search for more papers by this authorD. Vautrin, D. Vautrin Population, Génétique et Evolution, CNRS, 91198 Gif-sur-Yvette, FranceSearch for more papers by this authorM. Solignac, M. Solignac Population, Génétique et Evolution, CNRS, 91198 Gif-sur-Yvette, FranceSearch for more papers by this author A. Guiller, Corresponding Author A. Guiller Laboratoire de Parasitologie Pharmaceutique, CNRS UMR 6553, Faculté des Sciences Pharmaceutiques et Biologiques, 35043 Rennes, France, Annie Guiller. Fax: +02 99 33 68 96; E-mail: [email protected]Search for more papers by this authorJ.-F. Arnaud, J.-F. Arnaud Laboratoire de Parasitologie Pharmaceutique, CNRS UMR 6553, Faculté des Sciences Pharmaceutiques et Biologiques, 35043 Rennes, France, Laboratoire de Zoologie et d'Ecophysiologie, CNRS UMR 6553, Campus de Beaulieu, 35042 Rennes, France,Search for more papers by this authorD. Vautrin, D. Vautrin Population, Génétique et Evolution, CNRS, 91198 Gif-sur-Yvette, FranceSearch for more papers by this authorM. Solignac, M. Solignac Population, Génétique et Evolution, CNRS, 91198 Gif-sur-Yvette, FranceSearch for more papers by this author First published: 25 December 2001 https://doi.org/10.1046/j.1365-294x.2000.00954-13.xCitations: 16Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat References 1 Arnaud JF, Madec L, Bellido A, Guiller A (1999) Microspatial genetic structure in the land snail Helix aspersa (Gastropoda: Helicidae). Heredity, 83, 110 119. 2 Guiller A, Bellido A, Madec L (1998) Genetic distances and ordination: the land snail Helix aspersa in North Africa as a test case. Systematic Biology, 47, 208 227. 3 Guiller A, Madec L, Daguzan J (1994) Geographical patterns of genetic differentiation in the landsnail Helix aspersa Müller (Gastropoda: Pulmonata) . Journal of Molluscan Studies, 60, 205 221. 4 Madec L & Guiller A (1994) Geographic variation of distal genitalia in the landsnail Helix aspersa (Mollusca: Gastropoda). Journal of Zoology, 233, 215 231. 5 Terret JA (1992) The mitochondrial genome of Cepaea nemoralis. PhD Thesis, University of Nottingham, Nottingham. 6 Thomaz D, Guiller A, Clarke B (1996) Extreme divergence of mitochondrial DNA within species of pulmonate land snails. Proceedings of the Royal Society of London Series B, 263, 363 368. Citing Literature Volume9, Issue8August 2000Pages 1191-1193 ReferencesRelatedInformation