Combining a biotin-enrichment protocol and 454GS-FLX titanium pyrosequencing technology, we characterised 22 polymorphic microsatellite loci from the parasitic wasp, Habrobracon hebetor (Say) (Hymenoptera: Braconidae), a cosmopolitan species commonly used in biological control against a wide range of both major lepidopterous pests of stored products and field crops in different parts of the world. Three multiplex PCR sets were optimised and characterised across 46 H. hebetor specimens from two samples collected from millet fields in Niger. Two to 11 alleles were found per locus and observed heterozygosity ranged from 0.289 to 0.826. Polymorphism was detected in both samples with a similar level of observed heterozygosity (0.482 vs. 0.502) and number of alleles (4.1 vs. 3.6). Deviation from Hardy-Weinberg equilibrium was detected at the same five loci in both samples and five or seven more loci in each sample but was not associated with heterozygote deficiencies. Even though evidence for linkage disequilibrium was found between a few alleles, these new loci segregated independently. The variability of the 22 loci will enable estimates of genetic diversity and structure patterns, as well as gene flow between H. hebetor populations at different spatial scales. Cross-species amplifications were successful among the six Bracon spp. tested and nine loci will be particularly appropriate for population genetic studies in B. brevicornis., Madougou Garba, Anne Loiseau, Laure Benoit, Nathalie Gauthier., and Obsahuje bibliografii
The population structures of different species of Calliphoridae flies are highly diverse at different locations. We investigated populations of the Eastern European L. sericata using chaetotaxy and eight microsatellite loci. Our results strongly indicate that a panmictic population of L. sericata exists in the area studied, possibly with a high rate of intra-population gene flow. Analysis of chaetotaxy also supports the panmictic population hypothesis., Anna V. Diakova, Dmitry M. Schepetov, Nadezhda Y. Oyun, Anatole I. Shatalkin, Tatiana V. Galinskaya., and Obsahuje bibliografii
Currently it remains difficult to obtain robust microsatellite markers for Lepidoptera. In an attempt to overcome the problems associated with developing microsatellite markers for this insect order we combined (i) biotin-enrichment protocol, (ii) next generation pyrosequencing (through 454 GS-FLX Titanium technology) and (iii) the use of individuals collected from eight geographically distant European populations representing three subspecies of Euphydryas aurinia. Out of 96 stringently designed primer pairs, 12 polymorphic microsatellite loci amplified without obvious evidence of null alleles in eight individuals from different subspecies. Between five and seven of these loci showed full within population applicability and three revealed to be robust and transferable between populations and sub-species, providing a first step towards the development of a valuable and robust tool for studying conservation issues and evolution in E. aurinia populations. Nevertheless, as in most studies dealing with Lepidoptera microsatellites, null alleles were detected in most of the developed markers. Our results emphasize the need for further research in order to better understand the complex evolution and organization of Lepidopteran genomes. and Melthide Sinama, Vincent Dubut, Caroline Costedoat, André Gilles, Marius Junker, Thibaut Malausa, Jean-François Martin, Gabriel Nève, Nicolas Pech, Thomas Schmitt, Marie Zimmermann, Emese Meglécz.
Microsatellites are the most common markers used in population and conservation genetic studies. However, their isolation is laborious and expensive. In some taxa, such as Lepidoptera, it is particularly difficult to isolate microsatellite markers due to the high similarity of the flanking regions of different loci and the presence of null alleles. Here we isolated microsatellites of the endangered butterfly Boloria aquilonaris using 454 GS-FLX Titanium pyro-sequences of biotin enriched DNA libraries and tested the success of cross-amplification on the sister-species B. eunomia. Fifteen polymorphic microsatellite loci were isolated in B. aquilonaris using initially 101 stringently designed primer pairs. Unlike in many other studies of microsatellite isolation in Lepidoptera, few null alleles were detected and only at very low frequencies. Additionally, the raw data set can still be used for the isolation of other microsatellite loci. None of the selected polymorphic loci for B. aquilonaris gave clear banding patterns for B. eunomia, although about 15 other loci gave promising banding patterns for the latter species. Low intra- and inter-specific transferability of developed markers in this study also lends support to the hypothesis that the evolution of the genome of Lepidoptera is dissimilar from that of other organisms., Sofie Vandewoestijne, Camille Turlure, Michel Baguette., and Obsahuje seznam literatury
The cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is a serious pest of citrus in northern Iran, both because of the damaged caused by its feeding and as a vector of several viruses. The genetic structure of populations of A. gossypii on citrus trees at eight localities in Iran was surveyed using seven polymorphic microsatellite loci. Of 240 individuals tested, 142 multilocus genotypes (MLGs) were identified. The presence of multicopy genotypes and negative FIS values revealed that the major mode of reproduction in northern Iran is obligate parthenogenesis. The genotypic diversity of populations ranged between 0.24 and 0.93. Considerable genotypic diversity and a high frequency of unique MLGs, confirmed there is some cyclical parthenogenesis in the region. The analysis of molecular variance revealed high intrapopulation and weak interpopulation genetic differentiation (overall FST = 0.036) among the different populations. The UPGMA dendrogram of eight populations based on Nei's genetic distance indicated two clusters: genotypes from West of Mazandaran and Guilan provinces and those from East of Mazandaran. The same results were also obtained from the STRUCTURE analysis of these populations. This information on the genetic diversity of populations of A. gossypii in northern Iran could be useful for improving the Integrated Pest Management of this aphid.
Seven polymorphic microsatellite loci were developed for the planthopper Hyalesthes obsoletus, vector of stolbur 16SrXII-A phytoplasma. The loci have di- or trinucleotide repeat motifs and are highly variable with 10 to 22 alleles per locus. Observed heterozygosity ranged from 0.278 to 0.950 for the 78 individuals genotyped. One locus is sex-linked. No linkage between loci was found. All loci amplified consistently among phylogeographic as well as host-plant related samples and proved highly informative for population genetic studies. and Miriam IMO, Julia LÜNEBURG, Thomas HANKELN, Alfred SEITZ, Jes JOHANNESEN.
Wild type silkworm larvae have opaque white skin, whereas the mutants Sel (Sepialumazine) and Xan (Xanthous) are yellow-skinned. Previous genetic analysis indicated that Sel and Xan are on established linkage groups 24 (0.0) and 27 (0.0), respectively. However, in constructing a molecular linkage map using simple sequence repeat (SSR) loci, we found that the two mutations were linked. To confirm this finding, we developed a set of SSR markers and used them to score reciprocal backcross populations. Taking advantage of the lack of crossing-over in female silkworms, we found that the progeny of backcrosses between F1 females and males of the parental strains (BC1F) of the two visible mutations had the same inheritance patterns linked to the same SSR markers. This indicated that the two visible mutations belonged to the same chromosome. To confirm this finding, we tested for independent assortment by crossing Sel and Xan marker strains with each other to obtain F1 and F2 populations. Absence of the expected wild type class among 5000 F2 progeny indicated that the two visible mutations were located on the same linkage group. We carried out recombination analysis for each mutation by scoring 190 progeny of backcrosses between F1 males and parental females (BC1M) and constructed a linkage map for each strain. The results indicated that the Sel gene was 12 cM from SSR marker S2404, and the Xan gene was 7.03 cM from SSR marker S2407. To construct a combined SSR map and to avoid having to discriminate the two similar dominant mutations in heterozygotes, we carried out recombination analysis by scoring recessive wild type segregants of F2 populations for each mutation. The results showed that the Sel and Xan genes were 13 cM and 13.7 cM from the S2404 marker, respectively, consistent with the possibility that they are alleles of the same locus, which we provisionally assigned to SSR linkage group 24. We also used the F2 recessive populations to construct two linkage groups for the Sel and Xan genes.
We conducted a comparative population genetic analysis of levels of genetic variation and its geographical structuring in three closely related species of grasshopper that co-occur in the Mediterranean Basin: Calliptamus italicus, C. barbarus and C. wattenwylianus. In the western part of their distributions 5 populations of C. italicus, 13 of C. barbarus and 10 of C. wattenwylianus were sampled. Bootstrap re-sampling of populations and microsatellite loci within each species indicated a lower level of genetic diversity and higher level of genetic differentiation in C. barbarus, which is less of an outbreak pest species than either of the other Calliptamus species studied. This may be due to lower effective sizes of non-outbreak populations and/or lower gene flow among them., Elodie Blanchet ... [et al.]., and Obsahuje seznam literatury