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Efeito de herbicidas no desenvolvimento inicial de variedades de cana-de-açúcar e no controle de plantas daninhasSabbag, Renan dos Santos 18 December 2015 (has links)
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Previous issue date: 2015-12-18 / Não recebi financiamento / The chemical method of weed control is the most used in the culture of sugarcane, and studies covering not only the management of plants, but also the effect of these herbicides on crop development, especially in new varieties. Therefore, this study was conducted with the objectives: (1) evaluate the effectiveness of control of ametryne herbicides, clomazone, diuron + hexazinone, metribuzin, saflufenacil, sulfentrazone and tebuthiuron used in isolation and in combination, in controlling Ipomoea nil, Ipomoea triloba and Merremia cissoides, submitted to different periods of drought, with 0, 20, 40 and 60 days without irrigation; (2) evaluate the effect of ametryne herbicides, clomazone, diuron + hexazinone, metribuzin, saflufenacil, sulfentrazone and tebuthiuron in the early development of varieties of sugarcane through pre-sprouted seedlings. The tests were conducted in a greenhouse in the CCA / UFSCar with controlled irrigation sprinkler. 4-liter pots were used, filled with sandy clay loam soil. The experimental design was completely randomized with four repetitions, in both parts of the project. At work on effectiveness of herbicides in weed control, herbicides were applied on the ground and subjected to drought periods of 0, 20, 40 and 60 days before sowing the weed species. After the drought 0, 20 40 and 60 days, the seeds of Ipomoea nil, Ipomoea triloba and Merremia cissoides were sown with minimal soil disturbance and evaluations were made 45 days after sowing (DAS), visually We used a percentage scale. In working with seedlings of sugarcane varieties, herbicides were applied at 3 and 10 days after transplantation of pre-sprouted seedlings and were made visual assessments with 7, 15, 30 and 60 days after treatments (DAT), also using a visual scale ranging from 0 to 100%. In quantitative assessments we evaluated the plant height parameters (m), leaf area (cm2) and shoot dry biomass (g) with 60 DAT. With respect to efficiency in weed control there was a reduction of saflufenacil herbicides control efficiency, clomazone, ametryne and metribuzim when subjected to drought periods. In the case of saflufenacil control efficacy was maintained until 20 days of drought. The varieties of pre-sprouted seedlings (BPMs) were shown to be different in phytotoxicity and biometric parameters in relation to the applied herbicide. The treatment saflufenacil + clomazone is phytotoxic to as sugarcane cuttings, however, depending on the variety, did not affect its dry biomass. The metribuzin, was the most selective herbicide in association with saflufenacil, saflufenacil isolated showed phytotoxicity below 30% in all varieties. / O método químico de controle de plantas daninhas é o mais utilizado na cultura da cana-de-açúcar, sendo necessários estudos que englobem não só o manejo das plantas, mas também o efeito destes herbicidas sobre o desenvolvimento da cultura, principalmente nas novas variedades. Portanto, este trabalho foi desenvolvido com os objetivos: (1) avaliar a eficácia de controle dos herbicidas ametrina, clomazone, diuron+hexazinone, metribuzim, saflufenacil, sulfentrazone e tebuthiuron utilizados de maneira isolada e em associação, no controle de Ipomoea nil, Ipomoea triloba e Merremia cissoides, submetidos a diferentes períodos de seca, sendo 0, 20, 40 e 60 dias sem irrigação; (2) avaliar o efeito dos herbicidas ametrina, clomazone, diuron+hexazinone, metribuzim, saflufenacil, sulfentrazone e tebuthiuron no desenvolvimento inicial de variedades de cana-de-açúcar por meio de mudas prébrotada. Os ensaios foram conduzidos em casa de vegetação no CCA/UFSCar com irrigação por aspersão controlada. Foram utilizados vasos de 4 litros, preenchidos com Latossolo Vermelho distrófico. O delineamento experimental foi inteiramente casualizado, com 4 repetições, nas duas partes do projeto. No trabalho sobre eficácia dos herbicidas no controle de plantas daninhas, os herbicidas foram aplicados sobre o solo e submetidos a períodos de seca de 0, 20, 40 e 60 dias, antes da semeadura das espécies daninhas. Após os períodos de seca 0, 20 40 e 60 dias, as sementes de Ipomoea nil, Ipomoea triloba e Merremia cissoides foram semeadas com o mínimo revolvimento do solo e as avaliações foram feitas aos 45 dias após a semeadura (DAS), de forma visual utilizou-se uma escala percentual. No trabalho com mudas de variedades de cana, os herbicidas foram aplicados aos 3 e 10 dias após o transplante das mudas pré-brotadas e foram feitas avaliações visuais com 7, 15, 30 e 60 dias após a aplicação dos tratamentos (DAT), também se utilizando uma escala visual com notas entre 0 e 100%. Nas avaliações quantitativas avaliou-se os parâmetros altura de planta (m), área foliar (cm2) e biomassa seca de parte aérea (g) com 60 DAT. Com relação a eficácia no controle de plantas daninhas observou-se uma redução da eficiência de controle dos herbicidas saflufenacil, clomazone, ametrina e metribuzim, quando submetidos à períodos de seca. No caso de saflufenacil a eficácia de controle se manteve até os 20 dias de período de seca. As variedades de mudas pré-brotadas (MPBs) mostraram ser diferentes quanto à fitotoxicidade e parâmetros biométricos em relação ao herbicida aplicado. O tratamento de saflufenacil + clomazone foi o mais fitotoxico às mudas de cana-de-açúcar, contudo, dependendo da variedade, não afetou sua biomassa seca. O metribuzim, foi o herbicida mais seletivo, em associação com o saflufenacil, o saflufenacil isolado mostrou fitotoxicidade abaixo de 30% em todas as variedades.
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Anticancer activity of ceratotheca trilobaNaicker, Leeann January 2016 (has links)
Submitted in complete fulfillment for the Degree of Doctorate of Philosophy in Biotechnology, Durban University of Technology, Durban, South Africa, 2016. / Plants have provided a source of medicine from the beginning of human history and are the core of modern medicine. Moreover, plant based drug discovery has led to the development of various anticancer drugs (such as vincristine, vinblastine, etoposide, paclitaxel, camptothecin, topotecan and irinotecan). The use of botanical, phytochemical, biological and molecular techniques have facilitated the discovery of anthraquinones from Ceratotheca triloba that can inhibit the human topoisomerase II enzyme (target for anticancer drugs) and kill cancer cells. However, the C. triloba plant has not been extensively studied for its anticancer activity. Therefore, the aim of this study was to further investigate the anticancer activity of C. triloba and determine the classes of compounds that contributed towards its activity.
In this study the leaf and root extracts were prepared by using hexane, DCM, hexane: DCM (1:1), methanol and/or water. These extracts were examined for their growth inhibitory potential on three cancer cell lines (A375 [melanoma], MDA-MB-231[breast] and WHCO1 [esophageal]) by using the MTT assay. Then, different mobile phases were prepared for optimizing the separation of the compounds of the active extract by TLC. Column chromatography was performed with the active extract by using five mobile phases (hexane : DCM [60 : 40, 40 : 60], DCM, DCM : ethyl acetate [90 : 10, 70 : 30, 60 : 40, 50 : 50, 50 : 60, 30: 60, 20 : 80], ethyl acetate and ethyl acetate: methanol [80 : 20, 70 : 30, 50 : 50]). The fractions collected from the column were examined for their growth inhibitory potential on two melanoma cell lines (A375 and UACC-62). The IC50 and TGI (total growth inhibition) values of the active fractions were determined. Also, the apoptosis inducing effects of the active fractions and standards (camptothecin and doxorubicin) were determined by using flow cytometer based assays (FITC annexin assay, PE active caspase 3 assay and BD MitoScreen assay). Subsequently, the chemical structures of the compounds that contributed towards the activity of these fractions were obtained by EI-LC-MS analysis.
The results demonstrated that the hexane root extract exhibited the best percentage of growth inhibition (%GI) on all three cancer cell lines. The separation of the compounds of the hexane root extract was optimized on TLC plates by using different ratios of hexane and DCM. Column chromatography allowed for fractionation of this extract. Purified compounds were not obtained due to co-elution. Further research would have to be conducted to obtain purified compounds. This may involve the use of mini-column chromatography and PTLC. Overall a total of ten combined fractions were collected from the column. Four of these fractions (F2, F4, F5 and F8) displayed a high %GI on the A375 and UACC-62 cell lines. Moreover, fraction F4 was the most active fraction as it had the lowest IC50 (0.70 µg.ml-1 [A375] and 0.39 µg.ml-1 [UACC-62]) and TGI (12.50 µg.ml-1[A375] and 25 µg.ml-1 [UACC-62]) values in comparison to the other fractions.
All four fractions induced depolarization of the mitochondria membrane potential (ΔΨ), caspase 3 activation, early apoptosis (phospholipid phosphatidylserine exposure) and/or late apoptosis in the melanoma cells. The results also revealed that fraction F4 (25 µg.ml-1) induced depolarization of the ΔΨ in a higher percentage of A375 (78.11%) and UACC-62 (87.4%) cells than the other fractions and standards. This fraction also induced caspase 3 activation in a high percentage of A375 (90.56%) and UACC-62 (96.78%) cells. Therefore fraction F4 was also the most active fraction in terms of apoptosis activity. Based on our results and literature findings we can deduce that the active fractions induced the intrinsic or extrinsic (type II) apoptosis pathway in the melanoma cells.
Six classes of compounds were identified from the four active fractions. These were: benzothiophenones, benzopyranones, naphthoquinones, anthraquinones, androstanes and quinazolines.
In conclusion, this is the first study that evaluated the growth inhibition potential of the leaf and root extracts of C. triloba on a panel of cancer cells. This research indicated that the hexane root extract displayed the best levels of cell growth inhibition. The active constituents of this extract were isolated into four fractions which elicited apoptosis inducing effects that promoted the extrinsic (type II) or intrinsic apoptosis pathway in the melanoma cells. Furthermore, fraction F4 contained the most active compounds from C. triloba as it had the lowest IC50 and TGI values (in comparison to the other fractions) and induced depolarization of the ΔΨ in the highest percentage of melanoma cells. It was confirmed that six classes of compounds were accountable for the anticancer activity of these fractions. Thus, the C. triloba plant is a rich source of anticancer compounds. / D
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Glyphosate, suas combinações com outros herbicidas e formulações no controle de plantas daninhas importantes na cultura da soja /Ferreira Neto, Mario Eduardo. January 2011 (has links)
Orientador: Robinson Antonio Pitelli / Banca: Ricardo Victória Filho / Banca: Silvano Bianco / Resumo: A adoção da tecnologia Roundup-Ready® de controle de plantas daninhas na cultura da soja foi bastante rápida e extensa expondo-a a uma grande diversidade de situações de composição especifica de comunidades infestantes, características edáficas e climáticas e de práticas agrícolas. Em alguns anos, passaram a serem identificadas plantas daninhas com maiores dificuldades de controle pelo glyphosate e que passaram a ser selecionadas e suas importâncias aumentadas nos agroecossistemas. Com o objetivo de estudar o controle de plantas daninhas em soja geneticamente modificada para tolerância ao glyphosate dois ensaios foram conduzidos um a campo e outro em condições de casa de vegetação. O ensaio de campo foi conduzido no Pontal do Paranapanema e foram avaliados os controles de plantas daninhas e seletividade à cultura da soja do glyphosate aplicado isolado e em combinação com diclosulam, cloransulam-methyl, flumioxazin e s-metolachlor. Foram dois grupos de tratamentos: um com aplicação única e outro com aplicação seqüencial de glyphosate. No campo, o experimento obedeceu ao delineamento em blocos ao acaso. Os resultados mostraram que aplicações seqüenciais proporcionaram melhor controle de Commelina benghalensis, mas não incrementaram o de Ipomoea triloba. Os melhores níveis de produtividade foram obtidos nas parcelas tratadas com a combinação de flumioxazin ou s-metolachlor com glyphosate, com ou sem aplicação seqüencial. Um segundo grupo de ensaios foi conduzido em vasos com o objetivo de avaliar a atividade biológica de diferentes doses e formulações do glyphosate em Macroptilium lathyroides, Euphorbia heterophylla e Senna obtusifolia em estádio de desenvolvimento em que regularmente há dificuldade de controle nas condições de campo. Todos os ensaios obedeceram ao delineamento... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The adoption of the Roundup-Ready® technology for weed control in soybeans was very quick and extensive. With the geographic expansion, the Roundup-Ready® soybeans met a big diversity of situations of weed composition, spil and climate features, and agronomic practices. After some years, certain weeds were identified as more tolerant to glyphosate and were selected in Roundup-Ready® soybean growing areas. So, two assays were carried out aiming to evaluate the weed control in Roundup-Ready® soybean. The first experiment was conducted under field conditions and the use of glyphosate alone or mixed with diclosulam, cloransulammethyl, flumioxazin, and s-metolachlor were evaluated under two situations: single spraying or followed of a complementary spraying of glyphosate, 14 days after the first one. The complementary application of glyphosate increased the Commelina benghalensis control, but did not change Ipomoea triloba control. The better productivity levels were achieved using the treatments with flumioxazin or s-metolachlor + glyphosate, with or without the complementary applicatrin. The second group of assays was carried under pot conditions out aiming to evaluate the biological activity of different doses and formulations of glyphosate in the control of Macroptilium lathyroides, Euphorbia heterophylla and Senna obtusifolia at growth stage in which some control difficulties were reported, under field conditions. A greenhouse essay was carried out under for each weed in the completely randomized experimental design with four replications. The treatments were arranged in a 3 x 4 factorial design considering three commercial formulations (Roundup Original®, Roundup-Ready® e Roundup Ultra®) and four doses (2,32; 1,68; 1,15 e 0,57 kg.ha-1) of glyphosate. Additionally, a control plot without chemical control was considered. The results showed that the three weeds had differential... (Complete abstract click electronic access below) / Mestre
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