Brazil has the highest biodiversity of native stingless bees in the world. However, Brazilian regulations are based on protocols standardized by the Organization for Economic Cooperation and Development (OECD), which uses Apis mellifera as a model organism. The safety of the use of an exotic species as a substitute for a native species is a problem that concerns members of the academy and the government agencies responsible for studies of this nature in the neotropical regions where there are occurrences of stingless bee species. Regarding the exposure of larvae to pesticides, several indicators suggest that the same rearing method for A. mellifera cannot be applied to stingless bees, mainly because of their different feeding systems. Thus, it is necessary to establish an in vitro rearing method for native social bees. We developed a larval rearing method for the stingless bee species Melipona scutellaris and evaluated parameters such as the defecation rate, pupation, emergence, mortality and morphometry of the newly emerged workers. The control was represented by the morphometry of individuals that emerged from natural combs (in vivo). In addition, we determined the average lethal concentration (LC50) of the insecticide dimethoate, the standard active ingredient used for the validation of toxicity tests. Procedures conducted prior to the in vitro bioassays allowed us to obtain the actual dimensions of the rearing cells for making acrylic plates for use in establishing how much each larva consumes during its development, that is, determining how much larval food should be placed in every artificial cell. Tests performed with M. scutellaris indicated an average of 80.2% emergence of individuals relative to the larvae, 92.61% relative to the pupae and a mean of 7.42% larval mortality. The mean of the intertegular distance, head width and wing asymmetry parameters were not significantly different between individuals from the in vitro and in vivo rearing methods. The LC50 value determined was 27.48 ng dimethoate / μL diet. The method described for M. scutellaris showed development rates above OECD standards, which requires at least 75% emergence, and produced newly emerged workers with similar dimensions to those produced under natural conditions; thus these results enable their use as a rearing protocol for this species (or genus) and, consequently, their use in toxicity tests. The results produced with M. scutellaris are the first steps for a proposed toxicity test protocol for stingless bee larvae that can be standardized and included as a protocol in the OECD.

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Resumo: No presente trabalho, visamos ampliar discussões acerca das diferentes faces da interação Universidade-Escola, com base na apresentação de relatos de experiências sobre o Projeto Primeiros Passos na Ciência e em reflexões teóricas sobre o contexto universitário, motivadas pela prática vivenciada. O projeto em questão foi desenvolvido por alunos de pósgraduação em Ciências Biológicas (Biologia Celular e Molecular) da UNESP, Campus de Rio Claro-SP em parceria com a Escola Estadual Prof. Marciano de Toledo Piza, de ensino médio, da cidade de Rio Claro, estado de São Paulo. Este projeto teve o objetivo de introduzir o aluno do Ensino Médio no cotidiano da pesquisa universitária na área de Biologia Celular e Molecular, com a expectativa de promover a aproximação destes alunos com o desenvolvimento do conhecimento científico e o ambiente universitário. Com a realização desse projeto, a Universidade teve a chance de adentrar no contexto dos alunos de Educação Básica, mais especificamente do Ensino Médio público. Esses novos conhecimentos podem criar a possibilidade de um futuro diferente, com mais conhecimentos científicos e instigando a reflexão a partir da rotina da Universidade e seu contexto. A experiência resultou na divulgação científica, no contato do aluno do Ensino Médio com o método científico e toda a técnica e objetividade que dele derivam, ampliando os laços comunidade-universidade.Abstract: In the present study, we intend to expand the discussion about different approaches of the University-School interaction, based on the presentation of an account of experiences with the First Steps in Science Project and theoretical reflections on the University context motivated by the lived experience. The project in question was developed by graduate students in Biological Sciences (Cell and Molecular Biology) at UNESP, Rio Claro/SP (Brazil), in partnership with Escola Estadual Prof. Marciano de Toledo Piza a public high school in the city of Rio Claro, State of São Paulo. This project had the objective of introducing high school students to the routine of university research in the area of Cell and Molecular Biology, with the expectation of promoting the approximation of these students with the development of scientific knowledge and the university environment. With the realization of this project, the University had the opportunity to better understand the primary education context of the students, specifically within public high schools. This new knowledge can create the possibility of a different future, with more scientific properties and instigating the reflection from the routine of the University and its context. The experience resulted in scientific dissemination, high school students' contact with the scientific method, and all the technique and objectivity derived from it, expanding community-university ties.

Due to the current practice of intensive pesticide use in Brazil on crops with flowers that are attractive to bees, biological information about Brazilian native bees is required in order for public authorities that are responsible for environmental safety to use them for calculations of risk assessments. Thus, the present study aimed to obtain biological data on stingless bees: Melipona scutellaris, Scaptotrigiona postica and Tetragonisca angustula. The food consumed by larvae and by adults and the mass of forager workers were obtained. The results provide essential inputs for the risk assessment of stingless bee exposure to pesticides., combined with information about the concentrations of these substances in crops with flowers that are attractive to bees, may be used in risk calculations.

Water is an important resource for stingless bees, serving for both honey dilution and the composition of larval food inside nests, yet can be an important route of exposure to pesticides. Assuming bees can forage naturally on pesticide-contaminated or noncontaminated areas, we investigated whether water supply influences the choice between neonicotinoid-dosed or nondosed feeders and on mortality of the stingless bee, Melipona scutellaris (Latreille, Hymenoptera, Apidae). At the field concentration, there was no significant mortality; however, the bees were not able to distinguish the feeders. In the cages containing high-concentration feeders, with water supply, the bees preferred nondosed food, and with no water, the mortality increased. Considering that in the field it is common to find extrapolated concentrations, our work suggested that water may allow avoidance of high dosed food and minimize mortality.

Stingless bees are the largest group of eusocial bees in the world. They play an essential role as crop pollinators and have been considered for inclusion in pesticide risk assessments (RAs). Beyond the mutualism involving stingless bee larvae and fungi, the fungivorous mite Proctotydaeus (Neotydeolus) alvearii proved to be interesting for studies of associations with stingless bees. Their presence is related to colony strength and health, showing a permanent-host-association level. Here, we tested whether the coexistence with P. (N.) alvearii affects stingless bee larvae survivorship and development, including when fed pesticide-dosed food. We chose dimethoate, the reference standard for toxicity tests, and thiamethoxam, widely used in neotropical crops and listed to be reassessed in RAs. Bees associated with the mites showed higher larval survivorship rates, even in the dosed ones, and revealed changes in the developmental time and body size. Our study represents the first approach to stingless bee responses to the coexistence of fungivorous mites inside brood cells, leading us to believe that these mites play a beneficial role in stingless bees, including when they are exposed to pesticides.

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