Molecular characterization and identification of digenean larval stages in Aylacostoma chloroticum (Prosobranchia: Thiaridae) from a neotropical floodplain.

Digeneans (Trematoda: Digenea) are endoparasites that present a complex life cycle, generally involving an intermediate invertebrate host and a vertebrate host. There is limited information about which species of molluscs may act as intermediate hosts in the upper Paraná River floodplain (UPRF), where Aylacostoma chloroticum can be considered a potential candidate. The study of digeneans in this region is important because some of these parasites are potentially zoonotic, and, therefore, are relevant to public health. However, the correct identification of these organisms during the larval stages is difficult because of the lack of morphologically diagnostic characteristics. The objective of this study was to identify and molecularly characterize the larval stages of digeneans found in A. chloroticum in the UPRF, using the mitochondrial marker of subunit I of cytochrome c oxidase and the 28S nuclear marker. The molluscs were examined in the laboratory and three morphotypes of cercariae were found. DNA was extracted from the specimens obtained and was then amplified and sequenced. The morphotypes exhibited high genetic similarities with Pseudosellacotyla, Paralecithodendrium and Philophthalmus, indicating that these organisms belong to these genera. This is the first record of larval stages of these genera in molluscs collected in the UPRF.

Genetic relationships of Plagioscion squamosissimus (Perciformes, Sciaenidae) from five Neotropical river basins evaluated using mitochondrial atpase6/8 gene sequences.

The genetic relationships of native or introduced Plagioscion squamosissimus in five Brazilian Neotropical basins were evaluated using the mitochondrial atpase6/8 genes. Results revealed that the population of the Tocantins River basin is more basal than the native populations of the Amazon and Parnaíba River basins. Moreover, the populations of P. squamosissimus that were introduced in the São Francisco and upper Paraná River basins originated from the population of the Parnaíba River.

Molecular characterization of the species Salvinia (Salviniaceae) from the upper Paraná River floodplain.

The pteridophytes Salvinia minima, S. herzogii, and S. auriculata are among the most abundant aquatic macrophytes in the upper Paraná River floodplain. Since some species have highly similar morphological features, it is very difficult to identify members of this genus to the species level. An indication of this difficulty is a set of poorly differentiated taxa comprising S. auriculata and S. herzogii known as the 'S. auriculata complex', which is found in the Paraná River together with other Salvinia species such as S. biloba and S. molesta. Some authors have reported the existence of inter-species hybrids. Despite the complex Salvinia taxonomy, few genetic studies have been performed on purported species within the genus to resolve this complexity. The present study was conducted to determine useful molecular sequences for the discrimination of Salvinia species of the upper Paraná River floodplain. Molecular data were compared with data of other species of the genus to clarify phylogenetic relationships, employing the nucleotide sequence trnL-trnF from the chloroplast DNA. The results revealed that Salvinia populations in the upper Paraná River floodplain belong to different species and indicated that species of the S. auriculata complex may be distinguished from one another after the division of the S. minima group, corroborating results by other researchers. Although the taxonomic position of S. oblongifolia was clarified, as high closeness between S. oblongifolia and the S. auriculata complex was reported, Salvinia kinship is still not thoroughly established and further investigations in morphology and molecular diversity are required.

A novel molecular marker for the study of Neotropical cichlid phylogeny.

The use of molecular markers has contributed to phylogeny and to the reconstruction of species' evolutionary history. Each region of the genome has different evolution rates, which may or may not identify phylogenetic signal at different levels. Therefore, it is important to assess new molecular markers that can be used for phylogenetic reconstruction. Regions that may be associated with species characteristics and are subject to selective pressure, such as opsin genes, which encode proteins related to the visual system and are widely expressed by Cichlidae family members, are interesting. Our aim was to identify a new nuclear molecular marker that could establish the phylogeny of Neotropical cichlids and is potentially correlated with the visual system. We used Bayesian inference and maximum likelihood analysis to support the use of the nuclear opsin LWS gene in the phylogeny of eight Neotropical cichlid species. Their use concatenated to the mitochondrial gene COI was also tested. The LWS gene fragment comprised the exon 2-4 region, including the introns. The LWS gene provided good support for both analyses up to the genus level, distinguishing the studied species, and when concatenated to the COI gene, there was a good support up to the species level. Another benefit of utilizing this region, is that some polymorphisms are associated with changes in spectral properties of the LWS opsin protein, which constitutes the visual pigment that absorbs red light. Thus, utilization of this gene as a molecular marker to study the phylogeny of Neotropical cichlids is promising.

Avaliação da dosagem de própolis pulverizada nas folhas de amoreira (morus sp.) sobre o desenvolvimento biológico e produtivo do bicho-da-seda (bombyx mori L. ) / Evaluación de la dosis de propóleos esparcidas en las hojas de morera (morus sp.) en el desarrollo biológico y productivo del gusano de seda (bombyx mori L.) / Evaluation of the doses of propolis pulverization in mulberry leaves (morus sp.) on the biological and productive development of silkworm (bombyx mori L.)

Este experimento foi realizado no Laboratório de Sericicultura, no Campus Sede da Universidade Paranaense (UNIPAR) de Umuarama, no período de 17/09/2009 a 17/10/2009, com o objetivo de verificar o efeito da própolis em diferentes dosagens na alimentação durante o desenvolvimento biológico do bicho-da-seda (Bombxy mori L). O método empregado na parte experimental foi a pulverização do extrato alcoólico de própolis, diluído em 500 mL de água destilada nas folhas de amoreira, nas seguintes dosagens, água-controle, 5mL, 10mL, 15mL e 20mL compondo os tratamentos T1, T2, T3, T4, T5, respectivamente. As folhas de amoreira foram fornecidas cinco vezes ao dia, durante o manejo alimentar. Verificou-se pelos resultados obtidos, que as diferentes dosagens de própolis utilizadas interferem no ganho de peso das lagartas, no peso dos casulos verdes e crisálidas quando comparado ao tratamento controle, influenciando também no número de casulos formados e, para os teores de seda bruto e líquido não apresentaram resultados significativos, quando comparados com o tratamento controle. Portanto, verificou-se que a própolis, nas dosagens utilizadas, não trouxe efeitos depressivos à biologia e produção do bicho-da-seda.

This experiment was conducted at the Sericulture Laboratory, in the Campus Sede of the Universidade Paranaense (UNIPAR) in Umuarama, from 17/09/2009 to 17/10/2009, in order to verify the effects of propolis in different dosages during the development of silkworm (Bombyx mori L). The method used during the experiment was the dillution of an alcohoolic solution of propolis, in 500 mL of destilled water with its further pulverization on mullberry leaves, with the following doses: water control; 5 mL; 10 mL; 15 mL; 20 mL, composing the following treatments: T1, T2, T3, T4, T5, respectively. The mullberry leaves were sprinkled five times a day, during the feed management. It was verified by the results that the different doses of propolis used interfere with gain-weight of the larvae, weight of cocoons and chrysalis, when compared to control. The treatment also influenced the number of cocoons formed. The contento fraw and liquid silk were not significant when compared with the control. Therefore, it was concluded that the propolis, used in those dosages, brought no depressive effects to the development and the production of silkworm.

Este experimento se realizó en el Laboratorio de Sericicultura del Campus Sede de la Universidad Paranaense (UNIPAR) de Umuarama, en el período de 17/09/2009 a 17/10/2009, con el objetivo de verificar el efecto de propóleos en diferentes dosis en la alimentación durante el desarrollo biológico del gusano de seda (Bombyx mori L.). El método usado en la parte experimental fue la pulverización del extracto alcohólico de propóleos, diluido en 500 ml de agua destilada en las hojas de morera, en las siguientes dosis: agua control, 5 ml, 10 ml, 15 ml y 20 ml componiendo los tratamientos T1, T2, T3, T4, T5, respectivamente. Las hojas de morera fueron suministradas cinco veces al día, durante el manejo alimentar. Por los resultados obtenidos se verificó que las dosis diferentes de propóleos utilizadas interfieren en el gano de peso de los gusanos, en el peso de los capullos verdes y crisálidas cuando comparado al tratamiento control, influenciando también en el número de capullos formados y, para contenidos de seda bruta y líquida no presentan resultados significativos, mientras comparado con el tratamiento control. Sin embargo, se puede verificar que propóleos, en dosis utilizadas, no trajo efectos depresivos a la biología y producción del gusano.