Isolation and genetic characterization of Lysinibacillus sphaericus strains found in mosquito larvae (Diptera: Culicidae)

Clara de Fátima Gomes Cavados,1 Eder Soares Pires,1 Jeane Quintanilha Chaves,1 Danielle Nunes Alvarez,1 Helio Benites Gil,2 Iris Braz Ribeiro de Oliveira,2 Andrea de Barros Pinto Viviani Cunha,2 Carlos José Pereira da Cunha de Araújo-Coutinho2 1Laboratory of Bacterial Physiology, Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Rio de Janeiro, 2Superintendência de Controle de Endemias – SUCEN, São Paulo, Brazil Introduction: Lysinibacillus sphaericus is a highly effective and specific bioinsecticide used for the control of Culicidae larvae. Objective: This study aimed to identify and characterize L. sphaericus strains isolated from Culex quinquefasciatus larvae in Brazil. Methods: C. quinquefasciatus larvae were collected from streams in the urban area of São Paulo state. L. sphaericus strains were identified through cytomorphology, biochemical, and physiological analyses. Qualitative bioassays were performed to evaluate the toxicity of the strains against C. quinquefasciatus. The crystal compound protein pattern of L. sphaericus strains was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Five reference strains were used as standards in all tests performed. Repetitive extragenic palindromic elements-polymerase chain reaction (REP-PCR) was utilized in an attempt to differentiate pathogenic and nonpathogenic isolates. Results: Twenty-one strains were isolated. Only one presented toxic activity against C. quinquefasciatus. REP-PCR results identified 23 patterns among the 26 strains used in the study, and the fragment analysis showed low similarity (16%) between L. sphaericus isolates and the five reference strains. Conclusion: Comparison of strains isolated in this study using REP-PCR showed a low similarity to other strains, demonstrating the high intraspecific variability for L. sphaericus. Keywords: Lysinibacillus sphaericus, Culicidae, SDS-PAGE, qualitative bioassays, REP-PCR, mosquitoes, entomopathogenic bacteria&nbsp

Visual and acoustic communication in neotropical birds: Diversity and evolution of signals

Animal communication is a key feature of intra- and inter-specific interactions in nature. Vocalizations and plumage coloration are two of the most exploited signaling pathways among birds and they have an important role in sexual selection and reproductive isolation. The evolution of vocal and visual signals and their efficiency to confer information are influenced by many factors, such as the signaler's morphology, the environment in which these are transmitted, or the sensitivity of either intended or unintended receivers like potential predators. In this chapter we review the diversity of visual and vocal signals among Neotropical birds which have been less studied than their counterparts from other biogeographic realms. The particularities they may present are not exceptions, but opportunities to gain a better understanding of avian communication and the factors influencing its evolution.Fil: Barreira, Ana Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: García, Natalia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Cornell Lab Of Ornithology; Estados Unido