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Environmental relevant concentrations of glyphosate-based herbicide as 50 µg l , 300 µg l and 1800 µg l can affect sperm quality of yellowtail tetra fish Astyanax lacustris. Viability of sperm cells was impaired at 300 µg l , a concentration that is within legal limits in U.S.A. waterbodies, while motility was impaired at 50 µg l , which is the more stringent limit set in Brazilian law. Therefore, environment protection agencies must review regulations of glyphosate-based herbicides on water bodies.

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The tomato plant has a specific relationship with native pollinators because the form of its flowers is adapted to buzz pollination carried out by some pollen-gatherer bees that vibrate their indirect flight muscles to obtain that floral resource. The absence and the low density of these bees in tomato fields can lead to pollination deficits for crop. The aim of this study is to demonstrate that open tomato flowers, probably visited by native pollinator, have greater pollen load on their stigma than unvisited flowers. Another objective is to show that this great pollen load increases fruit production. We selected crops of the Italian tomato cultivar in areas of the State of Goiás, Brazil. Thirty seven plants of three crops each had one inflorescence bagged in the field. Bagged and non-bagged flowers had their stigmas collected and the amount of pollen on their surfaces was quantified. For the comparison of fruit production, we monitored bagged and not-bagged inflorescences and after 40 days, their fruits were counted, weighed, measured and had their seeds counted. The amount of pollen grains on the stigma of flowers available to pollinators was higher than that on the stigma of bagged flowers. On average, fruit production was larger in not-bagged inflorescences than in bagged inflorescences. In addition, not-bagged flowers produced heavier fruits than did bagged flowers. There was a significant difference in the number of seeds between treatments, with significantly more seeds in the non-bagged fruit. Our results show that native bees buzz-pollinate tomato flowers, increasing the pollen load on their stigma and consequently fruit production and quality.

Glyphosate-based herbicides are widely used in agricultural systems. Although the target organism are particularly plant organisms, there are numerous studies showing adverse effects in aquatic animals, such as inhibition of acetyl cholinesterase, effects on kidney, liver, and gill and stressors effects. This study analyzed the effects of commercial formulation of glyphosate on feeding behavior in Pacu (Piaractus mesopotamicus). Fish were exposed to three glyphosate concentrations (0.2, 0.6, and 1.8 ppm) for 15 days. At concentrations of 0.2 and 0.6 ppm, food intake decreased on day 13 and then returned to normal on day 15. At the highest glyphosate-based herbicide concentration, 1.8 ppm, food consumption decreased dramatically and did not recover on day 15. This study showed that glyphosate-based herbicide at sub-lethal concentrations can affect feed intake in pacu and consequently inhibits its growth.

ResumoA leguminosa Leucaena leucocephala (Lam.) R. de Wit., conhecida como leucena, é originária da América Central, considerada pioneira, com populações de altas densidades, o que dificulta o desenvolvimento das espécies nativas. O presente estudo objetivou contribuir com informações sobre a biologia reprodutiva da L. leucocephala, referentes ao seu êxito reprodutivo. O estudo foi realizado em Trindade, Goiás, de julho a novembro de 2012. Foram selecionadas quatro áreas de estudo no município apresentando populações da leucena constituídas por, no mínimo, seis indivíduos em plena floração. Foram realizadas observações dos visitantes florais e testes de primeira, segunda e terceira visitas, além de polinização cruzada entre plantas, autopolinização e controle. Foram registrados 342 visitantes, distribuídos em 12 espécies de insetos com predominância de Apis mellifera (Linnaeus, 1758) e Trigona spinipes (Fabricius, 1793) nas áreas. A flor apresentou senescência ao fim do dia, mas houve decréscimo na abundância de insetos nos indivíduos de leucena após as 10 horas da manhã. Na avaliação do número de visitas de polinizadores e sua influência na produção de frutos, verificou-se que o número de visitas do principal polinizador (A. mellifera) não influenciou a produção de frutos, evidenciando a eficiência da abelha desde a primeira visita na flor. Leucaena leucocephala reúne vários atributos típicos de uma espécie invasora, como a ação eficiente de polinizadores generalistas (A. mellifera), propiciando produção considerável de frutos e sementes, contribuindo para o potencial dispersor da planta e sucesso reprodutivo nas áreas.Palavras-chave: polinização, Apis mellifera, sucesso reprodutivo. AbstractThe species Leucaena leucocephala (Lam.) R. de Wit., known as leucaena, is originally from Central America. It has been considered a pioneer with high densities of individuals in its populations that could prevent the development of native species. The present study aims to understand the reproductive biology of L. leucocephala, synthetizing information about its reproductive success. The study was conducted in Trindade, central Brazil, from July to November 2012. All areas contained specimens in bloom. We selected four study areas containing populations of leucaena with at least six individuals with flowering. Observations were made of floral visitors and we did tests of first, second and third visit, and cross-pollination between plants, self-pollination and control group (without human intervention). There was a predominance of Apis mellifera and Trigona spinips as flower visitors in these areas. The flowers undergo senescence at the end of the day, however, there is a decrease in flower visiting by insects after 10 am. We found 342 visitors belonging to 12 insect species. After assessing the number of visits of pollinators and their influence on fruit production, we found that the number of visits of the main pollinator (A. mellifera) does not influence the production of fruits, showing the efficiency of this bee in its...

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Agricultural use and management systems in tropical soils of the Brazilian Cerrado may directly influence its chemical properties, in the conventional cultivation systems with pastures or grains, as well as in areas with a crop-livestock-forest integration system. Thus, the objective was to evaluate the chemical attributes of the soil under different use and management systems. The research was carried out at Boa Vereda Farm, in the state of Goiás, Brazil. The experimental design was completely randomized with a 5 x 3 factorial arrangement divided into five production systems: (1) among the rows of Eucalyptus (CLFI), (2) within the rows of Eucalyptus (CLFI), (3) in conventional agricultural monoculture, (4) pasture, and (5) -natural Cerrado (control treatment). Samples were collected in three soil depths (0-0.5; 0.5-0.1 and 0.1-0.2 m), with four replicates each. Among the chemical properties of the soil studied, the organic matter, calcium, magnesium and potassium contents, base saturation, and cation exchange capacity, are higher in the soil with natural Cerrado. The area of agricultural monoculture showed the highest levels of phosphorus and copper, but has the lower levels of organic matter in the soil. The chemical properties of the soil were similar in the CLFI system, regardless of the evaluation point (within or among rows). The chemical properties of the soil evaluated were similar between the pasture cultivated in CLFI and the conventional system. Therefore, the land use and management system do not directly influence the chemical properties of the soils evaluated.