Queens remate despite traumatic mating in stingless bees.

Males can control female reproduction using genital plugs to impede access by rivals. In social bees, ants, and wasps, plugging may involve traumatic mating, with females being harmed. In stingless bees, chances are that plugs may promote ovarian activan, and are thought to ensure single mating-a general tendency among the social Hymenoptera. However, understanding on relationships between mating plugs, traumatic mating, and mating systems in stingless bees remains limited. To address this, we (1) compared mated queens of 7 Neotropical species to understand the patterns of copulatory marks in females and (2) compared pre- and post-mating genitalia of males and females in Melipona fasciculata to depict plug functional morphology. Data revealed an unprecedented consequence of mating in stingless bees: the characteristic marks left by mating plugs on female abdomens and the inferences that can be made from them. To our surprise, in 1 species M. fasciculata we found that queens retain the plug long after mating, and may carry it for the rest of their lives. All the other 6 species retained the plug for only a short period. Remated queens were only found in M. seminigra, whose multiple copulatory marks match previous findings of polyandry in this species. Our study shows that queens can remate, and suggests that male genital morphology may determine in part the time persistence of plugs. We conclude that traumatic mating plugs do not fully prevent remating in stingless bees and that mating systems are not uniform in this group. Nonetheless, exceptional cases of facultative polyandry in social insects-for example, when mating plugs fail-may confirm a general tendency for single mating in close link with efficient mating plugs.

Expression of methyl farnesoate epoxidase (mfe) and juvenile hormone esterase (jhe) genes and their relation to social organization in the stingless bee Melipona interrupta (Hymenoptera: Apidae).

Social organization in highly eusocial bees relies upon two important processes: caste differentiation in female larvae, and age polyethism in adult workers. Juvenile Hormone (JH) is a key regulator of both processes. Here we investigated the expression of two genes involved in JH metabolism - mfe (biosynthesis) and jhe (degradation) - in the context of social organization in the stingless bee Melipona interrupta. We found evidence that the expression of mfe and jhe genes is related to changes in JH levels during late larval development, where caste determination occurs. Also, both mfe and jhe were upregulated when workers engage in intranidal tasks, but only jhe expression was downregulated at the transition from nursing to foraging activities. This relation is different than expected, considering recent reports of lower JH levels in foragers than nurses in the closely related species Melipona scutellaris. Our findings suggest that highly eusocial bees have different mechanisms to regulate JH and, thus, to maintain their level of social organization.

Chromosomal mapping of repetitive DNA in Melipona seminigra merrillae Cockerell, 1919 (Hymenoptera, Apidae, Meliponini).

Melipona Illiger, 1806 is represented by 74 known species of stingless bees, distributed throughout the Neotropical region. Cytogenetically it is the most studied stingless bee genus of the tribe Meliponini. Member species are divided in two groups based on the volume of heterochromatin. This study aim was to analyze the composition and organization of chromatin of the stingless bee subspecies Melipona seminigra merrillae Cockerell, 1919 using classical and molecular cytogenetic techniques, so contributing to a better understanding of the processes of chromosomal changes within the genus. We confirm that M. seminigra merrillae has a chromosome number of 2n = 22 and n = 11, results that differ from those reported for the genus in the absence of B chromosomes. The heterochromatic pattern revealed a karyotype composed of chromosomes with a high heterochromatin content, which makes it difficult to visualize the centromere. Silver nitrate impregnation (Ag-NOR) showed transcriptionally active sites on the second chromosomal pair. Staining of base-specific fluorophores DAPI-CMA3 indicated a homogeneous distribution of intensely DAPI-stained heterochromatin, while CMA3 markings appeared on those terminal portions of the chromosomes corresponding to euchromatin. Similar to Ag-NOR, fluorescence in situ hybridization (FISH) with 18S ribosomal DNA probe revealed distinct signals on the second pair of chromosomes. Microsatellite mapping (GA)15 showed markings distributed in euchromatic regions, while mapping with (CA)15 showed marking patterns in heterochromatic regions, together with a fully marked chromosome pair. Microsatellite hybridization, both in heterochromatic and euchromatic regions, may be related to the activity of transposable elements. These are capable of forming new microsatellites that can be dispersed and amplified in different regions of the genome, demonstrating that repetitive sequences can evolve rapidly, thus resulting in within-genus diversification.

Nutritional composition and bioactive compounds of Melipona seminigra pot-pollen from Amazonas, Brazil.

BACKGROUND: Pot-pollen is a fermented product stored by stingless bees in cerumen pots and traditionally used as food or medicine by natives in tropical regions. Knowledge of pot-pollen composition from the Amazon region is important to strengthen the breeding of native bees and consequently contribute to sustainable development in this region. The aim of the present study was to determine the chemical composition of Melipona seminigra pot-pollen from Amazonas, Brazil. RESULTS: We report the identification of 21 phenolic compounds using ultra-performance liquid chromatography- electrospray ionization-quadrupole time-of-flight-mass spectrometry. Overall, the predominant constituents of pot-pollen were protein (333.8-470.7 g kg-1 ) and dietary fibers (247.6-353.3 g kg-1 ). The predominant fatty acids were polyunsaturated (44.95-59.57% of total fatty acid content) and the samples contained all essential amino acids. Total carotenoid content ranged from 3.2 to 48.0 µg g-1 , total flavonoid content (as catechin equivalents) from 1.9 to 4.5 mg g-1 , total reducing capacity (as gallic acid equivalents) from 7.0 to 15.0 mg g-1 , ferric-reducing antioxidant power from 2.8 to 8.9 µmol g-1 and oxygen radical absorbance capacity (as Trolox equivalents) from 224.9 to 1117.0 µmol g-1 . CONCLUSIONS: This study reports for the first time a comprehensive chemical characterization of M. seminigra pot-pollen. The samples presented antioxidant activity, high values of nutrients and bioactive compounds such as polyphenols, carotenoids, insoluble dietary fibers, polyunsaturated fatty acids, and essential amino acids, comparable to other health foods. © 2021 Society of Chemical Industry.

Transposable DNA Elements in Amazonian Fish: From Genome Enlargement to Genetic Adaptation to Stressful Environments.

Transposable elements have driven genome evolution and plasticity in many ways across a range of organisms. Different types of biotic and abiotic stresses can stimulate the expression or transposition of these mobile elements. Here, we cytogenetically analyzed natural fish populations of the same species living under different environmental conditions to test the influence and organization of transposable elements in their genome. Differential behavior was observed for the markers Rex 1, Rex 3, and Rex 6 in the chromosomes of individuals of the same species but coming from different environments (polluted and unpolluted). An increase in the number of Rex transposable elements in the chromosomes and their influence on the genome of populations living in a polluted environment indicates that they must be under constant adaptive evolution.

Effects of environmental pollution on the rDNAomics of Amazonian fish.

Pollution is a growing environmental problem throughout the world, and the impact of human activities on biodiversity and the genetic variability of natural populations is increasingly preoccupying, given that adaptive processes depend on this variability, in particular that found in the repetitive DNA. In the present study, the mitochondrial DNA (COI) and the distribution of repetitive DNA sequences (18S and 5S rDNA) in the fish genome were analysed in fish populations inhabiting both polluted and unpolluted waters in the northern Amazon basin. The results indicate highly complex ribosomal sequences in the fish genome from the polluted environment because these sequences are involved primarily in the maintenance of genome integrity, mediated by a systematic increase in the number of copies of the ribosomal DNA in response to changes in environmental conditions.

Impact of environmental temperatures on mortality, sex and caste ratios in Melipona interrupta Latreille (Hymenoptera, Apidae).

Temperature is a major driver of biological phenomena, from metabolism to ecological interactions and rates of evolutionary diversification. However, species vary greatly in their thermal tolerance, as well as the temperature under which they perform best. This study aimed to investigate the effect of experimental manipulation of environmental temperatures on the individual mortality and phenotypic composition of colonies of Melipona interrupta. To fulfill these objectives, 30 colonies in equivalent developmental conditions were artificially subjected to different temperatures. Temperatures were monitored by thermo-hygrometers, and immature mortality and sex and caste ratios were observed in brood combs during 14 months. A strong effect of external temperature on immatures was detected on deviations from 28 to 30 °C (the natural average temperature inside the colony), causing an increase in mortality. Likewise, a significant effect of temperature on sex ratio was detected, with male:female ratio decreasing at temperatures below and above 28-30 °C. Lastly, there was no clear evidence for an effect of temperature on caste ratio, although queens appeared to become relatively more frequent at warmer temperatures. The results of this study allow us to conclude that anthropogenic changes, whose effect can be extrapolated to the similar natural changes, that modify the environmental temperatures to which M. interrupta colonies are exposed are likely to compromise their survival, mainly through individual mortality.

Molecular characterization of the gene profile of Bacillus thuringiensis Berliner isolated from Brazilian ecosystems and showing pathogenic activity against mosquito larvae of medical importance.

The occurrence of Aedes aegypti, Culex quinquefasciatus, and mosquitoes of the genus Anopheles potentiate the spread of several diseases, such as dengue, Zika, chikungunya, urban yellow fever, filariasis, and malaria, a situation currently existing in Brazil and in Latin America. Control of the disease vectors is the most effective tool for containing the transmission of the pathogens causing these diseases, and the bacterium Bacillus thuringiensis var. israelensis has been widely used and has shown efficacy over many years. However, new B. thuringiensis (Bt) strains with different gene combinations should be sought for use as an alternative to Bti and to prevent the resistant insects selected. Aiming to identify diversity in the Bt in different Brazilian ecosystems and to assess the pathogenicity of this bacterium to larvae of Ae. aegypti, C. quinquefasciatus, and Anopheles darlingi, Bt strains were obtained from the Amazon, Caatinga (semi-arid region), and Cerrado (Brazilian savanna) biomes and tested in pathogenicity bioassays in third-instar larvae of Ae. aegypti under controlled conditions in the laboratory. The isolates with larvicidal activity to larvae of Ae. aegypti were used in bioassays with the larvae of C. quinquefasciatus and An. darlingi and characterized according to the presence of 14 cry genes (cry1, cry2, cry4, cry10, cry11, cry24, cry32, cry44Aa, cry1Ab, cry4Aa, cry4Ba, cry10Aa, cry11Aa, and cry11Ba), six cyt genes (cyt1, cyt2, cyt1Aa, cyt1Ab, cyt2Aa and cyt2Ba), and the chi gene. Four hundred strains of Bt were isolated: 244 from insects, 85 from Amazon soil, and 71 from the Caatinga biome. These strains, in addition to the 153 strains isolated from Cerrado soil and obtained from the Entomopathogenic Bacillus Bank of Maranhão, were tested in bioassays with Ae. aegypti larvae. A total of 37 (6.7%) strains showed larvicidal activity, with positive amplification of the cry, cyt, and chi genes. The most frequently amplified genes were cry4Aa and cry4Ba, both occurring in 59.4% in these strains, followed by cyt1Aa and cyt2Aa, with 56.7% and 48% occurrence, respectively. Twelve (2.2%) strains that presented 100% mortality within 24h were used in bioassays to estimate the median lethal concentration (LC50) for Ae. aegypti larvae. Two strains (BtMA-690 and BtMA-1114) showed toxicity equal to that of the Bti standard strain, and the same LC50 value (0.003mg/L) was recorded for the three bacteria after 48h of exposure. Detection of the presence of the Bt strains that showed pathogenicity for mosquito larvae in the three biomes studied was possible. Therefore, these strains are promising for the control of insect vectors, particularly the BtMA-1114 strain, which presents a gene profile different from that of Bti but with the same toxic effect.

Physicochemical characteristics of pollen collected by Amazonian stingless bees / Características físico-químicas do pólen coletado por abelhas amazônicas sem ferrão

ABSTRACT: The purpose of this study was to determine the physicochemical characteristics of pollen collected by the Amazonian stingless bees Melipona seminigra and Melipona interrupta, in order to verify whether their characteristics meet the physicochemical requirements established by the Brazilian Technical Regulation for Identity and Quality of Bee Pollen. Physicochemical analyses were performed through official analytical methods. Results of pollen analyses collected by M. seminigra and M. interrupta were respectively as follows: moisture: 53.39 and 37.12%; protein: 37.63 and 24.00%; lipids: 10.81 and 6.47%; ash: 4.03 and 2.74%; crude fiber: 9.30 and 13.65%; carbohydrates: 25.66 and 44.27%; energy: 350.47 and 331.33kcal%; pH: 3.70 and 3.34; total solids: 46.60 and 62.87%, and water activity: 0.91 and 0.85. The percentages of moisture and pH in pollen collected by both studied bees are not in agreement with the Technical Regulation for bee pollen. Since some characteristics, which are inherent to the Melipona pollen, were not in conform to the current Regulation, we recommend that further studies should be conducted to better characterize it, and correct the Regulation, if necessary.

RESUMO: O objetivo deste estudo foi determinar as características físico-químicas do pólen coletado pelas abelhas amazônicas sem ferrão, Melipona seminigra e Melipona interrupta, para verificar se suas características atendem aos requisitos físico-químicos estabelecidos no Regulamento Técnico Brasileiro de Identidade e Qualidade de Pólen Apícola. As análises físico-químicas foram realizadas através de métodos analíticos oficiais. Os resultados das análises do pólen coletado por M. seminigra e M. interrupta foram, respectivamente: umidade: 53,39 e 37,12%; proteínas: 37,63 e 24,00%; lipídeos: 10,81 e 6,47%; cinzas: 4,03 e 2,74%; fibra bruta: 9,30 e 13,65%; carboidratos: 25,66 e 44,27%; energia: 350,47 e 331,33kcal%; pH: 3,70 e 3,34; sólidos totais: 46,60 e 62,87%; e atividade de água: 0,91 e 0,85. O percentual de umidade e o pH do pólen coletado por ambas as abelhas estudadas está em desacordo com o Regulamento Técnico para pólen apícola. Recomendamos que sejam realizados mais estudos para melhor caracterizar este produto e atualizar o Regulamento vigente, se necessário, pois algumas características que não atendem ao Regulamento são inerentes ao pólen de Melipona.

Molecular characterization of the gene feminizer in the stingless bee Melipona interrupta (Hymenoptera: Apidae) reveals association to sex and caste development.

In highly eusocial insects, development of reproductive traits are regulated not only by sex determination pathway, but it also depends on caste fate. The molecular basis of both mechanisms in stingless bees and possible interaction with each other is still obscure. Here, we investigate sex determination in Melipona interrupta, focusing on characterization and expression analysis of the feminizer gene (Mi-fem), and its association to a major component of caste determination, the juvenile hormone (JH). We present evidence that Mi-fem mRNA is sex-specifically spliced in which only the female splice variant encodes the full length protein, following the same principle known for other bee species. We quantified Mi-fem expression among developmental stages, sexes and castes. Mi-fem expression varies considerably throughout development, with higher expression levels in embryos. Also, fem levels in pupae and newly emerged adults were significantly higher in queens than workers and males. Finally, we ectopically applied JH in cocoon spinning larvae, which correspond to the time window where queen/worker phenotypes diverge. We observed a significantly increase in Mi-fem expression compared to control groups. Since up to 100% of females turn into queens when treated with JH (while control groups are composed mainly of workers), we propose that fem might act to regulate queens' development. Our findings provide support for the conserved regulatory function of fem in Melipona bees and demonstrate a significant correlation between key elements of sex and caste determination pathways, opening the avenue to further investigate the molecular basis of these complex traits.

Bees for development: Brazilian survey reveals how to optimize stingless beekeeping.

Stingless bees are an important asset to assure plant biodiversity in many natural ecosystems, and fulfill the growing agricultural demand for pollination. However, across developing countries stingless beekeeping remains an essentially informal activity, technical knowledge is scarce, and management practices lack standardization. Here we profited from the large diversity of stingless beekeepers found in Brazil to assess the impact of particular management practices on productivity and economic revenues from the commercialization of stingless bee products. Our study represents the first large-scale effort aiming at optimizing stingless beekeeping for honey/colony production based on quantitative data. Survey data from 251 beekeepers scattered across 20 Brazilian States revealed the influence of specific management practices and other confounding factors over productivity and income indicators. Specifically, our results highlight the importance of teaching beekeepers how to inspect and feed their colonies, how to multiply them and keep track of genetic lineages, how to harvest and preserve the honey, how to use vinegar traps to control infestation by parasitic flies, and how to add value by labeling honey containers. Furthermore, beekeeping experience and the network of known beekeepers were found to be key factors influencing productivity and income. Our work provides clear guidelines to optimize stingless beekeeping and help transform the activity into a powerful tool for sustainable development.

Antimicrobial activity of honeys from two stingless honeybee species and Apis mellifera (Hymenoptera: Apidae) against pathogenic microorganisms / Atividade antimicrobiana de méis de duas espécies de abelhas sem ferrão e Apis mellifera (Hymenoptera, Apidae) contra micro-organismos patogênicos

Honeys are described possessing different properties including antimicrobial. Many studies have presented this activity of honeys produced by Apis mellifera bees, however studies including activities of stingless bees honeys are scarce. The aim of this study was to compare the antimicrobial activity of honeys collected in the Amazonas State from Melipona compressipes, Melipona seminigra and Apis mellifera against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Chromobacterium violaceum, and Candida albicans. Minimum inhibitory concentrations were determined using the agar dilution method with Müller-Hinton agar (for bacteria) or Saboraud agar (for yeast). Staphylococcus aureus and E. faecalis were inhibited by all honeys at concentrations below 12%, while E. coli and C. violaceum were inhibited by stingless bee honeys at concentrations between 10 and 20%. A. mellifera honey inhibited E. coli at a concentration of 7% and Candida violaceum at 0.7%. C. albicans were inhibited only with honey concentrations between 30 and 40%. All examined honey had antimicrobial activity against the tested pathogens, thus serving as potential antimicrobial agents for several therapeutic approaches.

Méis são descritos possuindo diferentes propriedades, incluindo a antimicrobiana. Muitos estudos têm apresentado essa atividade de méis produzidos por abelhas Apis mellifera, no entanto estudos incluindo atividades de méis de abelhas sem ferrão são escassos. O objetivo deste estudo foi comparar a atividade antimicrobiana de méis de Melipona compressipes, Melipona seminigra e A. mellifera, coletados no Estado do Amazonas, contra Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Chromobacterium violaceum, e Candida albicans. As concentrações inibitórias mínimas foram determinadas usando o método de diluição em ágar, com ágar Muller-Hinton (para bactérias) ou ágar Sabouraud (para a levedura). S. aureus e E. faecalis foram inibidos por todos os méis em concentrações inferiores a 12%, enquanto E. coli e C. violaceum foram inibidos por méis de abelhas sem ferrão em altas concentrações entre 10 e 20%. A. mellifera inibiu E. coli na concentração de 7% e C. violaceum em baixa concentração (0,7%). C. albicans foi inibida apenas em concentrações entre 30 e 40% dos méis. Assim, todas as variedades de mel testadas apresentaram atividade antimicrobiana sobre os patógenos testados, servindo assim como agente antimicrobiano potencial para diversas abordagens terapêuticas.

Five egg-laying queens in a single colony of brazilian stingless bees (Melipona scutellaris Latreille / Presença de cinco rainhas fisogástricas em colônia de abelha sem ferrão (Melipona scutellaris Latreille)

Polygyny, characterized by the presence of several egg-laying queens, is considered as a temporary colony status. In stingless bees it is rarely observed. This paper reports the first case of natural polygyny in Melipona scutellaris colony, with five egg-laying queens.

Poliginia, caracterizada pela presença de mais de uma rainha poedeira, é considerada como uma condição temporária em colônias. Em abelhas sem ferrão isso é raramente observado. Este artigo registra o primeiro caso de poliginia natural em colônia de Melipona scutellaris, com cinco rainhas poedeiras.

Analysis of the intercaste transcriptional profile of Melipona scutellaris Latreille, 1811 (Hymenoptera, Apidae, Meliponini) by mRNA differential display.

In colonies of Melipona scutellaris Latreille, 1811 workers can be found with four ganglion nerve cells, a morphological characteristic of the queen. It is hypothesized that these workers, called intercastes, or phenocopies, are phenotypically-like workers, but genotypically identical to queens due to this specific trait. Workers with the same number of ganglion as queens seem to be intercastes between queens and workers. Our objective was to analyze the mRNA pro files of workers, queens, and intercastes of M. scutellaris through DDRT-PCR. Three hundred (300) pupae with white eyes were collected and externally identified according to the number of abdominal nerve ganglions: workers (5 ganglions), queens (4 ganglions) and intercastes (4 ganglions). The analysis identified differentially expressed transcripts that were present only in workers, but absent in intercastes and queens, confirming the hypothesis, by demonstrating the environmental effect on the queen genotype that generated phenotype-like workers.

Analysis of the intercaste transcriptional profile of Melipona scutellaris Latreille, 1811 (Hymenoptera, Apidae, Meliponini) by mRNA differential display

In colonies of Melipona scutellaris Latreille, 1811 workers can be found with four ganglion nerve cells, a morphological characteristic of the queen. It is hypothesized that these workers, called intercastes, or phenocopies, are phenotypically-like workers, but genotypically identical to queens due to this specific trait. Workers with the same number of ganglion as queens seem to be intercastes between queens and workers. Our objective was to analyze the mRNA pro files of workers, queens, and intercastes of M. scutellaris through DDRT-PCR. Three hundred (300) pupae with white eyes were collected and externally identified according to the number of abdominal nerve ganglions: workers (5 ganglions), queens (4 ganglions) and intercastes (4 ganglions). The analysis identified differentially expressed transcripts that were present only in workers, but absent in intercastes and queens, confirming the hypothesis, by demonstrating the environmental effect on the queen genotype that generated phenotype-like workers.

Atividades de vôo de operárias de Melipona seminigra (Hymenoptera: Apidae) em um sistema agroflorestal da Amazônica / Flight activities in Melipona seminigra workers (Hymenoptera: Apidae) in Amazonia

Atividades externas de vôo estão associadas a coleta de néctar, pólen, resina e barro e transporte de lixo para fora da colônia. Informações sobre esse trabalho das abelhas sem ferrão são importantes para atender a programas de manejo de polinizadores, reflorestamento e restauração ambiental e ainda a manutenção das populações silvestres destes insetos. Duas colônias de Melipona seminigra foram instaladas em um sistema agroflorestal constituído por variados tipos de espécies vegetais frutíferas e madeireiras para observações diárias de suas cargas transportadas. Um total de 17434 indivíduos foi observado sendo que 9355 (54%) transportavam pólen, 4195 (24%) resina, 2754 (16%) barro e 1130 (6%) néctar/água. O pólen foi o principal recurso coletado em ambas as colônias de junho a agosto de 2005 com pico de coleta matutino seguido por resina, barro e néctar/água, enquanto que no inicio da tarde a quantidade de cargas transportadas, em ordem decrescente, foi barro > resina > néctar/água > pólen. As temperaturas internas das colônias tiveram menor variação do que as temperaturas externas mostrando que abelhas M. seminigra também regulam a temperatura interna. Com a intensa atividade de forrageamento concluiu-se que o sistema agroflorestal pode ser uma interessante alternativa para a criação de abelhas sem ferrão.

Flight activities can be related to nectar, pollen, resin and clay collection, as well as garbage dumping to outside's hive. Information about this stingless bee work are important to attend pollinators management programs, reforest and environment recuperation with maintenance of these insects population. Four hives of Melipona seminigra were installed in an agro-forestry system with a varied assortment of wood and fruit tree species. In a total of 17434 individuals were observed 9355 (54%) of the transports were done for pollen, 4195 (24%) for resin, 2754 (16%) mud and 1130 (6%) nectar/water. Polen was the main resource collected for both colonies from June to August of 2005 with picks in the mornings, followed by resin, mud and nectar/water. Early afternoon the quantity of charges transported, in decreasing order were mud > resin > nectar/water > pollen. The internal colonies temperatures had less variation if compared to the external temperatures, showing that M. seminigra bees also regulate the internal temperature. Due to the intense flight activity in the agro-forest system is an interesting alternative to keep stingless bees in these environments.

Efeito dos óleos vegetais de andiroba (Carapa sp) e Copaíba (Copaifera sp) sobre forídeo, pragas de colméias, (Diptera: Phoridae) na Amazônia Central / Effect of andiroba (Carapa sp) and copaiba's (Copaifera sp) vegetable oils on phorides, hives's prague (Diptera: Phoridae) in Central Amazonia

O conhecimento de substâncias repelentes para forídeos é um passo importante para a meliponicultura brasileira, pois esses insetos podem causar sérios danos às colméias de abelhas nativas. Os óleos de copaíba e andiroba, naturalmente encontrados na região amazônica, são muito utilizados pelos povos tradicionais da região como repelentes de insetos. Foi observado o efeito de dois óleos vegetais (andiroba e copaíba) sobre a postura de ovos por fêmeas de forídeos em condições de laboratório. A postura das fêmeas foi realizada preferencialmente no substrato pólen e diferiu estatisticamente dos substratos contendo óleo de andiroba ou copaíba, nos quais houve considerável diminuição (até nenhuma postura), e do substrato contendo mel. Esses óleos são uma boa alternativa no controle preventivo e curativo dessa praga em colônias de Meliponineos, devido ao seu efeito repelente, ao baixo custo e disponibilidade na Região Amazônica.

The knowlegment of repellants substances to phoride flies is an important step to the Brazilian stinglessbee beekeeping due to the serious damage to the native bee hives they can do. The copaiba and andiroba oils, found commonly in the Amazon region, are very employed by the traditional people as insects' repellants. We observed the effect of these oils over the phoride's laying in laboratory conditions. The female phoride's eggs occurred preferentially in the pollen substrate and statistically differed from those containing andiroba and copaiba oils, which was strongly reduced (until none eggs were laid), and from the substrate containing honey. These oils showed to be quite good alternative for this plague's preventive and curative control in stingless bee hives due to its repellant effect, low cost, and availability to get it in the region.

Melitocoria de Zygia racemosa (Ducke) Barneby & Grimes por Melipona seminigra merrillae Cockerell, 1919 y Melipona compressipes manaosensis Schwarz, 1932 (Hymenoptera, Meliponina) en la Amazonía Central, Brasil / Melitocory of Zygia racemosa (Ducke) Barneby & Grimes by Melipona seminigra merrillae Cockerell, 1919 and Melipona compressipes manaosensis Schwarz, 1932 (Hymenoptera, Meliponina) in Central Amazon, Brazil

Durante el periodo de enero a abril de 2005 fueron encontradas semillas de Zygia racemosa, incorporadas al geoprópolis, en el interior de abejas sin aguijón en dos meliponarios experimentales en Manaus - AM. Fue observada intensa actividad de las obreras de M. seminigra merrillae y M. compressipes manaosensis llegando del campo con semillas fijas en las corbículas adheridas con resina y/o saliendo de las colonias con las semillas atrapadas en las mandíbulas. Ochenta semillas fueron recogidas en el interior de las colonias (mezcladas al geoprópolis en los basureros y fisuras) y también en el exterior, cerca de la entrada de las colonias, como resultado de la caída de esas semillas de las corbículas durante el vuelo de las obreras. Las semillas fueron plantadas en semilleros para la producción de esquejes y posterior identificación de la especie vegetal. Paralelamente se realizó el rastreo en campo en un radio de aproximadamente 3Km para la confirmación de la dispersión de las semillas, observaciones de comportamiento de las abejas forrajeando y recolección de semillas. Un total de 170 plántulas de Z. racemosa fueron encontradas en los alrededores del meliponario del GPA-INPA y 160 en el meliponario Vale Verde. Esos resultados indican que tanto M. compressipes manaosensis como M. seminigra merrillae recolectan y dispersan las semillas de Z. racemosa.

During the period from January to April 2005 seeds of Zygia racemosa were found incorporated in the nest structures, inside the colonies of stingless bee in two experimental meliponaries in Manaus - Am. It was registered an intense activity of the bee-workers of Melipona seminigra merrillae and M. compressipes manaosensis arriving from the field with seeds set in the corbiculae adhered with resin and/or leaving the colonies with the seeds clipped in their jaws. Eighty seeds were collected inside the colonies (mixed with the batume in the litter and/or cracks), and also outside them, near the entrance of the colony, as a result of the falling of corbiculae during the flight of the bee-workers. These seeds were planted in seedbeds for seedling production and posterior identification of the botanical species. As a way to confirm the scattering of the seeds, searches were done in the field (in an area of approximately 3km of extension), as well as observations of the collection of the seeds made by the bees. A total of 170 seedlings of Z. racemosa were found in the outskirts of the GPA-INPA meliponary and 160 in the Vale Verde meliponary. The results indicate that M. compressipes and M. seminigra collect and scatter the seeds of Z. racemosa.

Substituição natural de rainhas fisogástricas e distância de vôo dos machos em Tiuba (Melipona compressipes fasciculata Smith, 1854) e Uruçu (Melipona scutellaris Latreille, 1811) (Apidae, Meliponini) / Natural substitutions of queens and flight distance of males in tiuba (Melipona compressipes fasciculata Smith, 1854) and uruçu (Melipona scutellaris Latreille, 1811) (Apidae, Meliponini)

Este trabalho relata detalhes da vida reprodutiva de duas espécies de abelhas sem ferrão. Rainhas velhas de Melipona compressipes fasciculata, no Maranhão, morrem e são substituídas com sucesso em todos os meses. Rainhas de Melipona scutellaris, trazidas de Lençóis (BA - nordeste do Brasil) para Uberlândia (MG, centro-sudeste do Brasil) morreram durante todos os meses e não mostraram a existência de trimestre preferencial para as novas rainhas iniciarem postura. Quarenta machos de M. scutellaris, após serem marcados no tórax e libertados em grupos de 10 a 100, 400, 800 e 1000 metros do meliponário, tiveram seus retornos observados. Todos os machos libertados a 100 e 400 metros regressaram ao meliponário, 7 de 10 machos e 2 de 10 machos retornaram de 800 e 1000 metros, respectivamente. Os machos esperam constantemente pela saída de uma rainha virgem, próximos às colônias órfãs, o que indica que a maioria das rainhas é inseminada próximo aos seus ninhos, portanto, a dispersão dos genes depende do vôo dos machos e da distância de enxameagem para ocupação de uma cavidade para o novo ninho.

This work reports on the reproductive life of the stingless bees (Meliponini). Old queens of Melipona compressipes fasciculata in Maranhão State, Brazil die and are successfully substituted by new ones in all months. Queens of Melipona scutellaris from Lençois (BA - northeastern Brazil) brought to Uberlândia (Central South eastern Brazil) died during all months, and there are no months where new queens are more able to begin egg laying. Forty males of M. scutellaris were marked in the thorax and released in groups of 10 at 100, 400, 800 and 1000 meters from the meliponary and their return to it was observed. All males released at 100 to 400 meters returned, 7 out of 10 and 2 out of 10 males returned respectively from 800 and 1000 meters. Males are constantly waiting for a virgin queen next to orphan colonies, the majority of the queens is inseminated in near the hive, therefore, gene dispersion depends more upon the males and of the occupation of a new cavity for nest.