Bacharelado em Ciências Biológicas (UAST)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/2931
Siglas das Coleções:
APP - Artigo Publicado em Periódico
TAE - Trabalho Apresentado em Evento
TCC - Trabalho de Conclusão de Curso
Navegar
3 resultados
Resultados da Pesquisa
Item Atividade inseticida de óleos essenciais de Citrus spp. sobre Sitophilus zeamais em milho armazenado(2023-09-14) Alves, Maria Jéssica Pereira; Oliveira, Carlos Romero Ferreira de; Oliveira, Cláudia Helena Cysneiros Matos de; http://lattes.cnpq.br/1587027736201526; http://lattes.cnpq.br/2515051171734004; http://lattes.cnpq.br/4866960483577818Maize (Zea mays L.) is a cereal of great economic and social value. Its production is a world highlight, but there are significant losses caused by insect attacks. Among the insects that affect stored products, the coleopteran Sitophilus zeamais (Curculionidae) stands out, which causes damaging effects to the grain. In view of the indiscriminate use of synthetic insecticides to control insect pests, alternative methods are being increasingly studied, such as the use of plant compounds, particularly essential oils (EOs). The aim of this study was to assess the toxicity of the EOs of bitter orange (Citrus aurantium), sweet orange (Citrus sinensis), mandarin (Citrus reticulata) and bergamot (Citrus bergamia) on Sitophilus zeamais. The tests were carried out by contact and ingestion in order to estimate the lethal concentrations (LC50 and LC90) of each oil. Once the concentrations had been estimated, the repellency test was carried out with the LC50 on the insect. The four EOs were evaluated in the contact and ingestion test using different concentrations (0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 µL/20g) for a period of 48 hours, using 10 insects, 20g of maize, in 5 repetitions. In the repellency test, the lethal concentrations (LC50) of the four EOs were applied alone, using 10 insects, 20g of maize, in 10 repetitions, confined for 48 hours. In the contact and ingestion test, the percentages of insect mortality were counted and in the repellency test the insects attracted, as well as the number of adults that emerged in each treatment. In the contact and ingestion test, significant differences were observed at the lowest concentrations, with the most toxic EOs being bitter orange (C. aurantium) and bergamot (C. bergamia). The Repellency Index (RI) showed that the four EOs used had a repellent effect at all the concentrations tested. There was no significant difference in the emergence of S. zeamais on the treated maize kernels, indicating that they acted as oviposition inhibitors and/or had an ovicidal/larvicidal effect. Therefore, it was found that the EOs were promising for the management of S. zeamais in stored grain.Item Atividade inseticida dos óleos essenciais de Alecrim, Cravo-da-Índia, Cedroda-Virgínia e Toranja sobre Sitophilus zeamais em milho armazenado.(2023-05-03) Oliveira, Allysson Vinícius de Lima; Oliveira, Carlos Romero Ferreira de; http://lattes.cnpq.br/2515051171734004; http://lattes.cnpq.br/6582895019823815The maize weevil (Sitophilus zeamais Motschulsky) is a major primary pest in maize production and storage, causing significant damage to grains and facilitating infestation by secondary pests. Its reproductive capacity, long life cycle, and ability to survive at great depths among the grain explain its destructive potential. Given the damage caused by S. zeamais, the use of post-harvest technologies to control this pest is necessary and essential oils are a promising alternative because they do not pose a threat to human health or the environment. The aim of this study was to evaluate the toxicity of rosemary (Rosmarinus officinalis), clove (Eugenia caryophyllus), eastern red cedar (Juniperus virginiana), and grapefruit (Citrus paradisi) essential oils against S. zeamais. Contact and ingestion tests were conducted to determine the lethal concentrations (LC50 and LC90) of each essential oil, and evaluate the fumigant effect of C. paradisi and E. caryophyllus essential oils. The contact and ingestion experiments were conducted in Petri dishes containing 20g of maize, in which different concentrations of the evaluated essential oils were applied using an automatic pipettor. The plates were manually shaken to ensure that the oil spread between the grains and then, 10 adults of S. zeamais were confined in each plate for 48 hours. After this period, the percentage of mortality was analyzed, the results were subjected to PROBIT analysis, and lethal concentrations (LC50 and LC90) and the toxicity ratios (TR) were calculated. Each concentration was tested with 5 replicates. To evaluate the fumigant effect of C. paradisi and E. caryophyllus essential oils on S. zeamais, different concentrations of the oils were applied to filter paper strips, which were positioned on the bottom surface of the lid of glass containers with a volume equivalent to one liter.. In each fumigation chamber, 10 adults of S. zeamais were confined, using maize as substrate. An organza clothc barrier was placed to prevent direct contact of the insects with the oils. The experiment was carried out in an entirely randomized design with five repetitions. After 48 hours, mortality was analyzed and the results were submitted to Probit analysis. The results obtained demonstrated the insecticidal effect of C. paradisi, E. caryophyllus, R. officinalis, and J. virginiana essential oils on S. zeamais by contact and ingestion. The estimated lethal concentrations (LC50 and LC90) for the essential oils of C. paradisi (40.30 and 81.56μL/20g maize, respectively), R. officinalis (8.00 and 12.92μL/20g maize, respectively), and J. virginiana (39.42 and 102.20μL/20g maize, respectively), in the contact test corroborate with the literature. However, it was not possible to determine the LCs of E. caryophyllus, since already at the lowest concentration (0.5 μL/20g maize) it caused 100% mortality of insects. As fumigants, however, the essential oils of C. paradisi and E. caryophyllus did not show insecticidal activity, since they did not cause significant mortality even at the highest concentration tested (280μL/L of air). Among the oils evaluated in this study, R. officinalis showed the most promise for the management of S. zeamais, since it presented the lowest lethal concentrations (LC50 and LC90) and the highest toxicity ratio (RT).Item Atividade antibacteriana do óleo essencial de Croton tetradenius Baill frente a espécies de bactérias patogênicas(2019) Silva, Maria Aliny Nathalia Almeida; Silva, Ana Luiza da; http://lattes.cnpq.br/4162831591004569; http://lattes.cnpq.br/1069558787287430Medicinal plants of northeastern Caatinga are widely used in folk medicine by local communities, due to the therapeutic potential they present. Bacterial resistance to multiple drugs has increased in recently due to the indiscriminate use of antibiotics, generating the need for new broad spectrum drugs. Essential oils are known to be complex mixtures of volatile, lipophilic and odorous organic compounds that have numerous constituents due to secondary metabolites. This work aimed to evaluate the antimicrobial activity of Croton tetradenius (Euphorbiaceae) essential oil collected in the municipality of Triunfo-PE, obtained from the leaves by the hydrodistillation process. The evaluation was made by the paper disc diffusion method, in Petri plates, containing the MüellerHinton Agar medium, sown with bacterial suspensions previously adjusted to a 0.5 of the Mac Farland scale of three isolates. Discs containing 10 L and 15 L of the undiluted essential oil were added to the plates and incubated at 36 °C for 24 hours. Paper discs with the antibiotic Amikacin 30 μg/disc were used as positive control. The tests were performed in triplicates and the inhibition halos established in the average of the halos measured for each species of bacteria. The results show that Croton tetradenius essential oil has antimicrobial activity against the tested isolates Staphylococus aureus and Escherichia coli, except for Klebsiella pneumoniae which was resistant to the tested essential oil.