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Anopheles darlingi is a major malaria vector in the Amazon region and, like other vectors, harbors a community of microorganisms with which it shares a network of interactions. Here, we describe the diversity and bacterial composition from the midguts and salivary glands of lab-reared and field-captured An. darlingi using metagenome sequencing of the 16S rRNA gene. The libraries were built using the amplification of the region V3-V4 16S rRNA gene. The bacterial community from the salivary glands was more diverse and richer than the community from the midguts. However, the salivary glands and midguts only showed dissimilarities in beta diversity between lab-reared mosquitoes. Despite that, intra-variability was observed in the samples. Acinetobacter and Pseudomonas were dominant in the tissues of lab-reared mosquitoes. Sequences of Wolbachia and Asaia were both found in the tissue of lab-reared mosquitoes; however, only Asaia was found in field-captured An. darlingi, but in low abundance. This is the first report on the characterization of microbiota composition from the salivary glands of An. darlingi from lab-reared and field-captured individuals. This study can provide invaluable insights for future investigations regarding mosquito development and interaction between mosquito microbiota and Plasmodium sp.

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Insect pests introduced in eucalyptus plantations in Brazil are mostly of Australian origin, but native microorganisms have potential for their management. High quality biopesticide production based on entomopathogenic fungi depends on adequate technologies. The objective of this study was to evaluate Mycoharvester® equipment to harvest and separating particles to obtain pure Metarhizium anisopliae conidia to manage Thaumastocoris peregrinus Carpintero & Dellapé, 2006 (Hemiptera: Thaumastocoridae). The Mycoharvester® version 5b harvested and separated M. anisopliae spores. The pure conidia were suspended in Tween 80® (0.1%) and calibrated to the concentrations of 1 x 106, 107, 108 and 109 conidia/ml to evaluate the pathogenicity, lethal concentration 50 and 90 (LC50, LC90) and lethal time 50 and 90 (LT50, LT90) of this fungus to T. peregrinus. This equipment harvested 85% of the conidia from rice, with production of 4.8 ± 0.38 x 109 conidia/g dry mass of substrate + fungus. The water content of 6.36% of the single spore powder (pure conidia) separated by the Mycoharvester® was lower than that of the agglomerated product. The product harvested at the concentrations of 108 and 109 conidia/ml caused high mortality to T. peregrinus third instar nymphs and adults. The separation of conidia produced by solid-state fermentation with the Mycoharvester® is an important step toward optimizing the fungal production system of pure conidia, and to formulate biopesticides for insect pest management.

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Soils present high fungal diversity, including entomopathogenic species. These fungi are used in pest control, providing easy production, multiplication, application, and dispersion in the field. The objective of the present study was to evaluate entomopathogenic fungal diversity in soils from eucalyptus and soybean crops and natural forest areas. These fungi were isolated using the "Bait Method" with Tenebrio molitor (Linnaeus, 1758) (Coleoptera: Tenebrionidae) larvae from 10 soil samples per area, collected at 10 cm deep in a zig-zag pattern. The isolated entomopathogenic fungi were cultivated in Petri dishes using PDA medium and their mycelia separated after seven days of incubation in a BOD-type chamber. Species of Aspergillus, Beauveria, Cordyceps, Fusarium, Metarhizium, Penicillium and Purpureocillium were identified. The "Bait Method" with T. molitor larvae is efficient to isolate entomopathogenic fungi with higher diversity from soils of the natural forest than the cultivated area.

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Soils present high fungal diversity, including entomopathogenic species. These fungi are used in pest control, providing easy production, multiplication, application, and dispersion in the field. The objective of the present study was to evaluate entomopathogenic fungal diversity in soils from eucalyptus and soybean crops and natural forest areas. These fungi were isolated using the "Bait Method" with Tenebrio molitor (Linnaeus, 1758) (Coleoptera: Tenebrionidae) larvae from 10 soil samples per area, collected at 10 cm deep in a zig-zag pattern. The isolated entomopathogenic fungi were cultivated in Petri dishes using PDA medium and their mycelia separated after seven days of incubation in a BOD-type chamber. Species of Aspergillus, Beauveria, Cordyceps, Fusarium, Metarhizium, Penicillium and Purpureocillium were identified. The "Bait Method" with T. molitor larvae is efficient to isolate entomopathogenic fungi with higher diversity from soils of the natural forest than the cultivated area.

A diversidade de fungos, incluindo espécies entomopatogênicas, é alta nos solos. Esses fungos são utilizados no manejo de pragas com facilidade de produção, multiplicação, aplicação e dispersão no campo. O objetivo foi avaliar a diversidade de fungos entomopatogênicos em solos de culturas de eucalipto e soja e áreas de mata nativa. Fungos entomopatogênicos foram isolados pelo "Bait Method" com larvas de Tenebrio molitor (Linnaeus, 1758) (Coleoptera: Tenebrionidae) de 10 amostras de solo por área, coletadas a 10 cm de profundidade em zig-zag. Os fungos isolados foram cultivados em três placas de Petri em meio BDA e seus micélios separados após sete dias de incubação em câmara tipo BOD. Fungos dos gêneros Aspergillus, Beauveria, Cordyceps, Fusarium, Metarhizium, Penicillium e Purpureocillium foram identificados. O "Bait Method" com larvas de T. molitor é eficiente para isolar fungos entomopatogênicos com maior diversidade em solos de área de mata nativa que naqueles com culturas de eucalipto e soja.

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Plant parasitic nematodes reduce the production of agricultural crops. Species diagnosis is essential to predict losses, determine economic damage levels and develop integrated pest management programs. DNA extraction techniques need to be improved for precise and rapid molecular diagnosis of nematodes. The objective of the present study was to evaluate the efficiency of DNA extraction and amplification by PCR, cost and execution time by Chelex, Worm Lysis Buffer Method (WLB), Holterman Lysis Buffer Method (HLB) and FastDNA methods for nematodes of the Meloidogyne genus. The qualitative and quantitative efficiency of DNA extraction varied between methods. The band size of the amplified PCR product with WLB, Chelex and HLB methods was 590 bp. Extraction with the FastDNA is not recommended for DNA extraction from nematodes because it results in a low DNA concentration without bands in PCR amplification, besides presenting high cost. The efficiency of the WLB method to extracting DNA from Meloidogyne javanica was greater, ensuring a higher concentration and purity of the extracted material and guaranteeing lower costs and greater ease of PCR amplification.

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INTRODUCTION: Regenerative therapies using biomaterials require accurate information on interactions between the implanted material and the human body. To improve the process of bone regeneration it is necessary to obtain a better understanding of the influence of the surfaces on the early stages of osseointegration. This work aims to investigate the dynamic interaction between simulated body fluid (SBF) and titanium surfaces (Ti cp) immediately after their first contact. METHODS: Ti cp samples were passed through physicochemical treatments after immersion in acid solution, alkaline solution and solutions containing TiO2 and Ca2+, to obtain three different surfaces. These were characterized by electron microscopy and free energy estimates. The evaluation of the interaction with SBF was performed by measuring the dynamic contact angles after contacting the surfaces. RESULTS: The effects of SBF wettability were more significant on surfaces according to high energy estimates. A comparative analysis of the three types of surfaces showed that fluid spreading was greater in samples with greater polar components, indicating that the surface nature influences interactions in the early stages of osseointegration. CONCLUSION: The results indicate the influence of polar interactions in the dynamic wettability of the SBF. It is possible that these interactions can also influence cellular viability on surfaces. Based on these results, new experiments are being designed to improve the presented methodology as a tool for the evaluation of biomaterials without the need for in vivo experiments.