Estudos moleculares de espécies do gênero Trichogramma Westwood, 1833 (Hymenoptera: Trichogrammatidae) e detecção de Wolbachia spp. (Rickettsiales: Anaplasmataceae).

• Ano de defesa: 2012
• Autor(a) principal: Santos, Nilene Rodrigues dos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal da Paraí­ba; Brasil; Zoologia; Programa de Pós-Graduação em Ciências Biológicas; UFPB
• Palavras-chave em Português: Sistemática molecular; Diversidade genética; Parasitóide de ovos; Proteobactéria; Molecular systematics; Genetic diversity; Egg parasitoid; Proteobacteria; CIENCIAS BIOLOGICAS::ZOOLOGIA
• Link de acesso: https://repositorio.ufpb.br/jspui/handle/tede/4106

Trichogramma species are identified by the morphology of the male genitalia, making the identification difficult due to the small size of the individual (0.25 mm) and/or the presence of cryptic species. Therefore molecular biology constitutes a good alternative for the identification of Trichogramma species and is also used in the identification of Proteobacteria of the genus Wolbachia, known to induce parthenogenesis in Trichogramma species. The purpose of this thesis was to use molecular methods to identify Trichogramma species, verify the diversity of Trichogramma pretiosum populations in 11 cities in Brazil and its association with bacteria of the genus Wolbachia. The samples of Trichogramma pretiosum species and Trichogramma populations were submitted to extraction of genomic DNA for PCR using the forward primer ITS-2- 5 TGTGAACTGCAGGACACATG-3 and the reverse primer IT2-5 GTCTTGCCTGCTCTGCTCTGAG.-3`. The DNA products obtained from Trichogramma species and populations of T. pretiosum were purified and sequenced. To detect the presence of bacteria of the Wolbachia genus in T. pretiosum populations, the amplifications were done using wsp specific primers, with a final reaction volume of 25 μl. The size of PCR products was determined using a molecular weight marker 100 bp using a negative control without DNA, the remaining components and a positive control containing Wolbachia. It can be verified that it was possible to extract DNA from all the Trichogramma species with quantities and qualities sufficient for electrophoretic profiles with genomic DNA concentrations ranging from 15.3 to 50ng/μl. Using PCR, the fragments of the ITS2 region of ribosomal DNA were amplified and one can identify the species of Trichogramma with the sequencing by using the similarity search of the BLAST program in the GenBank database (NCBI - National Center for Biotechnology Information) and dendrogram analysis performed according to the genetic distance matrix, from which three groups were formed, the first by T. exigum, the second by T. pretiosum and the third by T. galloi. With the results of the query by similarity using the BLAST program in the GenBank database a maximum identification average of 92,2% was obtained regarding the species of Trichogramma pretiosum, confirming the correct sequencing. The size of the sequences ranged from 355 to 503 bp. The average G + C content (guanine + cytosine) was 53,2%. After aligning the 11 sequences of T. pretiosum, 391 sites were found conserved, reflecting 73% of the total of 536 sites found, confirming the similarity between samples, as well as confidence in the sequences obtained. The average found for this distance matrix was 0.30. According to the dendrogram obtained from the genetic distance matrix using the neighbor-joining method one can verify the presence of four groups, the first formed by the TPAES, TPPARS, TPRMT TPCVMT populations and the second by the TPSPMT population, the third group by the TPPPE, TPMVCE, TPPPB, TPPPMT, TPJSP populations, and the fourth by the TPPLMT population, being the most genetically distant population. The geographical distance did not affect the genetic similarity or dissimilarity between parasitoids having no significant difference between geographic distance and genetic similarity of the T. pretiosum samples in the locations collected. Of the T. pretiosum populations analyzed, the presence of viii endobacterias occurred in the population from the state of Espírito Santo, the first local record of the presence of this α proteobacteria for the species.