Pyriculariopsis calatheae sp. nov., a novel anamorphic hyphomycete from the Atlantic forest of Brazil causing leaf spots on Calathea longifolia

The new species Pyriculariopsis calatheae is described causing leaf spots on Calathea longifolia (Marantaceae). It represents an addition to the mycobiota of the tropical seasonal semi-deciduous montane forest, a component of the Brazilian Atlantic forest and a highly threatened ecosystem.     

Seroprevalence and Potential Risk Factors for Helicobacter pylori Infection in Brazilian Children

Background: Helicobacter pylori infection has been proved to be of great relevance to public health in unindustrialized countries, especially in low socioeconomic groups. Poor hygiene, deficient sanitation, and crowded conditions have been reported as risk factors for this infection. In this work, we investigated whether social and demographic characteristics were associated with anti‐H. pylori IgG antibodies in 1104 children aged 4–11 years old from Salvador, a large city located in northeastern Brazil. Methods: Standardized questionnaires were used to obtain social, demographic, and environmental data for the studied population in two periods of time (from 1997 to 2003 and in 2005). Anti‐H. pylori IgG antibodies were assessed by indirect enzyme‐linked immunosorbent assay in 2005. Results: Anti‐H. pylori IgG antibody was present in 28.7% of the children. Among the studied variables, the following were positively associated with the presence of anti‐H. pylori antibodies in multivariable analyses: age above 8 years old (OR = 1.72, 95% CI = 1.23–2.40), a larger sibling number (OR = 1.66, 95% CI = 1.26–2.18), nursery attendance (OR = 1.49, 95% CI = 1.04–2.12), location of the house at an unpaved street (OR = 2.03, 95% CI = 1.44–2.87) and absence of a flush toilet (OR = 1.32, 95% CI = 1.00–1.74). Conclusion: Our data show that H. pylori infection in children from a major Brazilian city is associated with variables indicative of a crowded environment and deficient sanitation/habitation conditions, leading to the conclusion that improvements in hygiene and social conditions may protect children against this infection.     

Transcriptional profiling of the AFL subfamily of B3-type transcription factors during the in vitro induction of somatic embryogenesis in the model legume Medicago truncatula

Plant Cell, Tissue and Organ Culture (PCTOC) - In many legume species, somatic embryogenesis is a limiting step of in vitro regeneration, with profound implications to genetic engineering and plant...     

A place preference test in the fish Nile tilapia

The Nile tilapia fish (Oreochromis niloticus) has a high potential to be used as a model in neuroscience studies. In the present study, the preference of the Nile tilapia between a gravel-enriched (GEE), a shelter-enriched (SEE) or a non-enriched (NEE) environment was determined, for developing a place preference model. Nile tilapia had an initial preference for GEE, but after 1 day of observation, the fish stabilized their frequency of visits among compartments. Hence, any stimulus motivating tilapia increase in compartment visiting indicates a positively reinforcing effect. This feature is very useful for the development of new behavioural paradigms for fish in tests using environmental discrimination, such as the conditioning place preference test.     

Biological performance of Diclidophlebia smithi (Hemiptera: Psyllidae), a potential biocontrol agent for the invasive weed Miconia calvescens

Diclidophlebia smithi Burckhardt, Morais and Picanço (Hemiptera: Psyllidae) is a promising biological control agent of Miconia calvescens DC. (Melastomataceae), a neotropical invasive weed in forest ecosystems in French Polynesia and Hawaii and a threat in Australia, where it was also introduced. A study on the reproductive performance of D. smithi under laboratory conditions through life expectancy and fertility tables is presented. Results indicated that this psyllid has a high reproductive capacity (R ₀>1 and r _m >0) and a short life cycle (46–47 days) and can have up to nine generations per year. The critical period of its life cycle is during the nymphal stage which is clearly inadequate for field introductions. The best age for introducing D. smithi against M. calvescens is the 4th day of the adult stage. D. smithi is easily mass-reared and has a short life cycle and a high reproductive capacity, which are desirable characteristics for a biological control agent.     

Using molecular markers for pedigree reconstruction of the greater amberjack (Seriola dumerili) in the absence of parental information

Ensuring appropriate levels of genetic diversity in captive populations is essential to avoid inbreeding and loss of rare alleles by genetic drift. Pedigree reconstruction and parentage analysis in the absence of parental genotypes can be a challenging task that relies in the assignment of sibship relationships among the offspring. Here, we used eight highly variable microsatellite markers and three different assignment methods to reconstruct the most likely genotypes of a parental group of wild Seriola dumerili fish based on the genotypes of six cohorts of their offspring, to assess their relative contributions to the offspring. We found that a combination of the four most variable microsatellites was enough to identify the number of parents and their contribution to the offspring, suggesting that the variability of the markers can be more critical than the number of markers. Estimated effective population sizes were lower than the number of breeders and variable among years. The results suggest unequal parental contribution that should be accounted for breeding programs in the future.     

Diet of peccaries (Tayassu tajacu and T. pecari) in a dry forest of Venezuela

The diets of Tayassu tajacu and T. pecari were assessed by means of direct observations, stomach content, and faecal analyses. The study was conducted in a dry forest located in the central Llanos region, Venezuela, where both species coexist. Peccaries were observed during one week of every month from August 1986 to May 1987. Fruits and seeds of Pithecellobium saman and Guazuma ulmifolia and roots and stems of Cissus rhombifolia comprised most of the diet of both peccary species. Proportions of these items differed significantly between species. There was no Acacia macracantha in stomachs nor in faeces of T. tajacu , but it was one of the most important items found in stomachs of T. pecari. Leaves appeared in all stomachs but in very low proportions (<1%). Insect pupae and larvae were found in small quantities. Results suggest that peccaries behave as frugivores and seed predators as most seed remains appeared cracked. Differences in the diet and behavioural traits described elsewhere may allow these similar species to coexist in the tropical dry forest of central Venezuela.