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Diamondback moth represents one of the major Brassicaceae plagues and the main current control method relies on the agrotoxins use. The search for alternative phytosanitary control methods demonstrates that the vegetal extracts have broadly studied and now represent a relevant option to control insects-plagues in small cultivation areas. Was evaluated the effect of the aqueous extract Tradescantia pallida 10% in oviposition and the feeding preference of Plutella xylostella, in laboratory conditions. That plant does not present herbivory reports, which raises the hypothesis of representing an efficient control alternative. P. xylostella couples introduced in experimentation cages for 10 days, to assess the activity of oviposition, being exposed to the botanic extract in the feeding and the oviposition substrate, with the eggs average number per day and fertility being assessed. To assess feeding, two tests developed: free choice and no choice of food source during 48 hours of evaluation. The results indicate that the aqueous T. pallida extract changes the oviposition activity of P. xylostella, reducing the average number of eggs per day and the fertility. It was also possible to observe the non-preference, regarding feeding, for substrates that were treated with the extract. The results observed in the study can contribute to amplify the small producers decision-making processes and the involved sectors regarding the choice of supplies that respect environmental and human health. El mes de diamonthback es una de las principales plagas de las Brassicaceas y el principal método de control en la actualidad es el uso de pesticidas. La búsqueda de métodos alternativos de control fitosanitario muestra que los extractos de plantas han sido ampliamente estudiados y representan una opción relevante en el control de plagas de insectos en pequeñas áreas de cultivo. El efecto del extracto acuoso de Tradescantia pallida al 10% sobre la actividad de oviposición y la preferencia alimenticia de Plutella xylostella se evaluó en condiciones de laboratorio. Esta planta no tiene reportes de herbivoría, lo que plantea la hipótesis de que representa una alternativa de control eficaz. Se introdujeron parejas de P. xylostella en jaulas experimentales durante 10 días para evaluar la actividad de oviposición y se expusieron al extracto botánico en el alimento y en el sustrato de oviposición, y se evaluó el número promedio de huevos diarios y la fertilidad Para evaluar la alimentación se desarrollaron dos pruebas: con y sin posibilidades de elegir la fuente de alimento en un período de evaluación de 48 horas. Los resultados indican que el extracto acuoso de T. pallida altera la actividad de oviposición de P. xylostella, reduciendo el número promedio de huevos diarios y la fertility. También se pudo observar la no preferencia de alimentación por sustratos tratados con el extracto. Los resultados observados en el estudio pueden contribuir a ampliar la toma de decisiones de los pequeños productores y los sectores involucrados en relación a la elección de insumos respetuosos con el medio ambiente y la salud humana. Diamonthback month é uma das principais pragas das brassicáceas e o principal método de controle atualmente é o uso de agrotóxicos. A procura por métodos alternativos de controle fitossanitário, evidencia que os extratos vegetais, vem sendo amplamente estudado e representa uma opção relevante no controle de insetos-praga em pequenas áreas de cultivo. Foi avaliado o efeito do extrato aquoso de Tradescantia pallida 10% na atividade de oviposição e preferência alimentar de Plutella xylostella, em condições de laboratório. Essa planta não apresenta relatos de herbivoria, o que levanta a hipótese de representar uma alternativa eficaz de controle. Casais de P. xylostella foram introduzidos em gaiolas de experimentação, durante 10 dias, para avaliação da atividade de oviposição e expostos ao extrato botânico na alimentação e no substrato de oviposição, sendo avaliado o número médio de ovos diários e fertilidade. Para avaliar a alimentação foram desenvolvidos dois testes: com e sem chances de escolha de fonte alimentar num período de 48 horas de avaliação. Os resultados indicam que o extrato aquoso de T. pallida altera a atividade de oviposição de P. xylostella, reduzindo o número médio de ovos diários e a fertilidade. Também foi possível observar a não preferência de alimentação por substratos tratados com o extrato. Os resultados observados no estudo podem contribuir para ampliar as tomadas de decisão dos pequenos produtores e os setores envolvidos em relação a escolhas de insumos que respeitem a saúde ambiental e humana.

In different parts of the world, it is verified that green areas provide an improvement in the quality and well-being of the population in the environmental and psychological aspects. In this study, the micronucleus test is performed in Tradescantia pallida (Rose) D.R. Hunt var. purpurea (TRAD-MCN) to detect the mutagenic potential of atmospheric gases in different situations of vehicular flow and urban green areas. Following the protocols for TRAD-MCN, the results obtained confirm the positive correlation between the intensity of vehicle traffic and the frequency of micronuclei. However, in regions with green areas, the results obtained with TRAD-MCN are inferior even with intense vehicular flow. The period of high temperatures and low relative humidity can potentiate the action of stressors on plant species used as a bioindicator. Because of the results found in this study, we can infer that green areas reduce the effects of polluting gases. We emphasize here the importance of preserving or creating parks and reserves in an urban environment to improve air quality and consequently the health of the population.

Made available in DSpace on 2018-11-26T17:54:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-09-01 Foundation for the Support and Development of Education, Science, and Technology (FUNDECT) of the state of Mato Grosso do Sul Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Biomonitoring is one of the tools used to assess the mutagenic potential of the atmosphere. In this study, the mutagenicity of Tradescantia pallida, a species of plant largely present in urban environments, was investigated. The objectives of this study was to estimate the mutagenic potential of vehicular flow through the TRAD-MCN bioassay in cities located at different altitudes in the southwest mesoregion of Mato Grosso do Sul, Brazil, to infer possible abiotic agents that may contribute to the effects of atmospheric pollutants, and finally to map the cities with greater risks to the health of the local population. To achieve these objectives, the Tradescantia-micronucleus test was performed on young buds of T. pallida collected between August 2015 and August 2016 in nine cities of Mato Grosso do Sul. These buds were exposed to traffic flows of various intensities. The data collected consisted of measurements of meteorological parameters and vehicular traffic counts for each city. The variables considered were: mean ambient temperature; micronuclei frequency; vehicular flow; altitude; relative humidity; pluviosity. The application of the Trad-MCN bioassay, with the consideration of environmental variables and altitudes, and the use of the Kernel interpolation technique, allowed us to map the areas with significant pollution risks to the population. The highest frequency of exposure to mutagens occurred in the cities with the highest vehicular traffic intensity. The average ambient temperature failed to show a linear association with the frequency of the micronuclei in the samples analyzed (r = 0.11(ns)). A positive correlation was observed between micronuclei frequency and vehicular flow, (r = 0.67; p