Dietas artificiais para a criação de larvas e adultos da mosca‑das‑frutas sul‑americana

The objective of this work was to adequate artificial diets for the development of larva and adult stages of South-American fruit fly (Anastrepha fraterculus). For the larval stage, the following diets were tested: D1, original diet, with 10 g agar; D2, modified diet, with 3.6 g agar; and D3, modified diet, with dry sugarcane bagasse. For adults, four diets were tested: A, brewers’ yeast + honey (2:1); B, refined sugar + yeast extract + crude wheat germ (3:1:1); C, soybean extract + brown sugar + crude wheat germ (3:1:1); and D, brewers’ dried yeast + honey (2:1). The evaluated biological parameters were: duration of the egg-pupa period, duration and feasibility of the pupa stage, average mass of pupae, sexual ratio, and duration and feasibility of the egg-adult period. Larval stage development for D1 and D2 was similar, and indicated that the larval rearing can be managed with 1/3 agar quantity used in D1. The dry sugarcane bagasse, used in the artificial diet, negatively affected the larval development. Artificial diets with brewers’ yeast + honey and with refined sugar + yeast extract + crude wheat germ are the most adequate ones for adult rearing.O objetivo deste trabalho foi adequar as dietas artificiais para o desenvolvimento dos estágios de larva e adulto da mosca‑das‑frutas sul‑americana (Anastrepha fraterculus). Para o estágio larval, foram testadas as seguintes dietas: D1, original, com 10 g de ágar; D2, modificada, com 3,6 g de ágar; e, D3, modificada, com bagaço seco de cana‑de‑açúcar. Para os adultos, foram testadas quatro dietas: A, levedura de cerveja + mel (2:1); B, açúcar refinado + extrato de levedura + gérmen de trigo cru (3:1:1); C, extrato de soja + açúcar mascavo + gérmen de trigo cru (3:1:1); e D, levedura seca de cervejaria + mel (2:1). Avaliaram-se os parâmetros biológicos de duração do período ovo‑pupa, duração e viabilidade do estágio de pupa, massa média de pupas, razão sexual e duração e viabilidade do período ovo‑adulto. O desenvolvimento larval em D1 e D2 foi semelhante e indicou que a criação de larvas pode ser realizada com 1/3 da quantidade de ágar da utilizada em D1. A utilização do bagaço seco de cana‑de‑açúcar, na dieta artificial, afetou negativamente o desenvolvimento larval. As dietas artificiais com levedura de cerveja + mel e com açúcar refinado + extrato de levedura + gérmen de trigo cru são as mais adequadas para a criação de adultos

Quality control and characterization of the testicles and ovaries of irradiated Anastrepha obliqua from Brazil

With the aim of making the application of the Sterile Insect Technique (SIT) feasible in the management of the West Indian fruit fly in Brazil, Anastrepha obliqua (Macquart) (Diptera: Tephritidae), a number of quality parameters required by the SIT were investigated in this study. The aim was to verify the influence of a range of doses of gamma radiation (40, 50, 60, 70 and 80 Gy) on the fertility of females and to evaluate several quality control parameters, such as fly emergence, sex ratio, flight ability and survival under stress, as well as the characterization of the morphology (measurement of length and width) of the ovaries and testicles of A. obliqua. Pupae with 24 h before adult emergence were irradiated at CENA/Universidade de São Paulo. The radiosterilization test showed no difference between treatments for the parameters of fly emergence, sex ratio and survival under stress. The radiation at doses above 40 Gy resulted in ovarian atrophy in females and the absence of egg production. In males, the radiation also affected testicular development. Considering the quality parameters assessed, the sterilization results obtained agreed with previous data in the literature for other A. obliqua strains, and the dose of 60 Gy could be considered as the best compromise between insect quality and full sterility for the Brazilian strain of A. obliqua evaluated

Infestation of guava by Anastrepha fraterculus (Diptera: Tephritidae): preferred ripening stages and influence of fruit peel coloration

The current study aimed to verify the preferred guava fruit ripening stage for egg laying by Anastrepha fraterculus (Diptera: Tephritidae) and to determine the influence of peel coloration of the fruits of 2 cultivars on infestation. The cultivars used were Paluma and Seculo XXI. The infestation level was evaluated in cages, considering 2 conditions: multiple-choice and nonchoice tests. The infestation levels of A. fraterculus differed between the green and the green-ripe stages in the multiple-choice test. In Paluma fruits with the nonchoice test, the infestation was highest during the ripe stage. There were no differences in infestation levels of A. fraterculus between the green and the green-ripe stages in Seculo XXI. In general, the green-ripe and the ripe stages were preferred for egg laying by A. fraterculus. In Paluma fruits there were significant correlations of infestation levels of A. fraterculus with luminosity (L) and chromaticity (C) in the nonchoice assay. In Seculo XXI fruits there was a significant correlation of infestation levels of A. fraterculus with color angle (h) in the nonchoice assay. No correlation was found between theses parameters in the multiple-choice test

Dietas artificiais para a criação de larvas e adultos da mosca-das-frutas sul-americana.

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Large scale artificial rearing of Anastrepha sp.1 aff. fraterculus (Diptera: Tephritidae) in Brazil

Some species of the genus Anastrepha (Diptera: Tephritidae) are successfully managed by matching the sterile insect technique with parasitoid releases. Such strategies used in integrated pest management can be implemented only where insect mass-rearing programs are feasible. In this study, we show the process of domestication, rearing technology and quality control data obtained from 54 generations of Anastrepha sp.1 aff. fraterculus (Wiedemann, 1830) kept under fully artificial conditions. Eggs were collected by an artificial oviposition panel consisting of one side of the cage made of blue voile fabric externally covered with a thin layer of silicon rubber. They were then air-bubbled in water at 25 ºC for 48 h before seeding. Larvae were reared on the regular laboratory artificial diet with 66 % of agar reduction turning over a semi-liquid diet, which reduced costs and improved insect quality. The adult and larval diets were composed of local ingredients including hydrolyzed yeast. When large-scale production of this fly is contemplated, the critical stage is larval development. This system of artificial rearing for A. fraterculus sp.1 developed in Brazil, allows for the production of a large number of insects of excellent quality using local ingredients and less agar in diet composition than the original medium used for this species. By reducing the interval of egg collection, the system might be optimized in terms of insect yield and, therefore, meet the demands of A. fraterculus sp.1 with regard to integrated pest management purposes

New protein sources in adults diet for mass-rearing of Anastrepha fraterculus (Diptera:Tephritidae)

The aim of this study was to find alternatives to reduce the cost of mass production of the South American fruit fly (A. fraterculus) by looking for locally available products as protein source in the diet of adults to replace the imported product without changing the quality parameters. Two yeast from a Brazilian company were evaluated. The quality parameters showed that the imported hydrolyzed yeast used in the adult diet could be perfectly replaced by the local products tested, with a reduction of over 80% of the cost of the diet. The quality of the produced insects remained the same and there were improvements in some quality parameters such as the volume of eggs produced, number of adults flying and longevity under the stress

The DNA Sensor AIM2 Protects against Streptozotocin-Induced Type 1 Diabetes by Regulating Intestinal Homeostasis via the IL-18 Pathway

Pattern recognition receptors (PRRs), such as Nod2, Nlrp3, Tlr2, Trl4, and Tlr9, are directly involved in type 1 diabetes (T1D) susceptibility. However, the role of the cytosolic DNA sensor, AIM2, in T1D pathogenesis is still unknown. Here, we demonstrate that C57BL/6 mice lacking AIM2 (AIM2−/−) are prone to streptozotocin (STZ)-induced T1D, compared to WT C57BL/6 mice. The AIM2−/− mice phenotype is associated with a greater proinflammatory response in pancreatic tissues, alterations in gut microbiota and bacterial translocation to pancreatic lymph nodes (PLNs). These alterations are related to an increased intestinal permeability mediated by tight-junction disruption. Notably, AIM2−/− mice treated with broad-spectrum antibiotics (ABX) are protected from STZ-induced T1D and display a lower pancreatic proinflammatory response. Mechanistically, the AIM2 inflammasome is activated in vivo, leading to an IL-18 release in the ileum at 15 days after an STZ injection. IL-18 favors RegIIIγ production, thus mitigating gut microbiota alterations and reinforcing the intestinal barrier function. Together, our findings show a regulatory role of AIM2, mediated by IL-18, in shaping gut microbiota and reducing bacterial translocation and proinflammatory response against insulin-producing β cells, which ultimately results in protection against T1D onset in an STZ-induced diabetes model