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Background: Anastrepha fraterculus is one of the most important fruit fly plagues in the American continent and only chemical control is applied in the field to diminish its population densities. A better understanding of the genetic variability during the introduction and adaptation of wild A. fraterculus populations to laboratory conditions is required for the development of stable and vigorous experimental colonies and mass-reared strains in support of successful Sterile Insect Technique (SIT) efforts. Methods: The present study aims to analyze the dynamics of changes in genetic variability during the first six generations under artificial rearing conditions in two populations: a) a wild population recently introduced to laboratory culture, named TW and, b) a long-established control line, named CL. Results: Results showed a declining tendency of genetic variability in TW. In CL, the relatively high values of genetic variability appear to be maintained across generations and could denote an intrinsic capacity to avoid the loss of genetic diversity in time. Discussion: The impact of evolutionary forces on this species during the adaptation process as well as the best approach to choose strategies to introduce experimental and mass-reared A. fraterculus strains for SIT programs are discussed. [ABSTRACT FROM AUTHOR]

Background: Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is a solitary parasitoid of Tephritidae (Diptera) fruit flies of economic importance currently being mass-reared in bio-factories and successfully used worldwide. A peculiar biological aspect of Hymenoptera is its haplo-diploid life cycle, where females (diploid) develop from fertilized eggs and males (haploid) from unfertilized eggs. Diploid males were described in many species and recently evidenced in D. longicaudata by mean of inbreeding studies. Sex determination in this parasitoid is based on the Complementary Sex Determination (CSD) system, with alleles from at least one locus involved in early steps of this pathway. Since limited information is available about genetics of this parasitoid species, a deeper analysis on D. longicaudata's genomics is required to provide molecular tools for achieving a more cost effective production under artificial rearing conditions., Results: We report here the first transcriptome analysis of male-larvae, adult females and adult males of D. longicaudata using 454-pyrosequencing. A total of 469766 reads were analyzed and 8483 high-quality isotigs were assembled. After functional annotation, a total of 51686 unigenes were produced, from which, 7021 isotigs and 20227 singletons had at least one BLAST hit against the NCBI non-redundant protein database. A preliminary comparison of adult female and male evidenced that 98 transcripts showed differential expression profiles, with at least a 10-fold difference. Among the functionally annotated transcripts we detected four sequences potentially involved in sex determination and three homologues to two known genes involved in the sex determination cascade. Finally, a total of 4674SimpleSequence Repeats (SSRs) were in silico identified and characterized., Conclusion: The information obtained here will significantly contribute to the development of D. longicaudata functional genomics, genetics and population-based genome studies. Thousands of new microsatellite markers were identified as toolkits for population genetics analysis. The transcriptome characterized here is the starting point to elucidate the molecular bases of the sex determination mechanism in this species.