The benefits of low UV dose treatment of horticultural produce – also known as hormetic treatment - have been attested to in numerous studies conducted over the last 15 years. However, commercial growers have not adopted the concept of hormesis. With increasingly stringent controls on the use of fungicides and other chemical agents the time has come to examine how hormetic treatment might be applied in the horticulture sector. The objectives of this work were firstly, to confirm UV-induced hormetic effects applied postharvest for a number of different types of produce, namely, tomatoes, broccoli, strawberries and mangoes. Secondly, to evaluate the use of rollers to ensure full surface treatment of produce, and thirdly to evaluate the possibility of treating produce preharvest. In order to investigate surface UV dose distributions, a polystyrene sphere (Diameter 70 mm) was used to simulate fruits such as tomatoes, apples, peaches etc., that have an approximately spherical form. Biodosimetry based on spores of Bacillus subtilis was employed to experimentally determine UV doses and to compare the results obtained with theoretical predictions. Good agreement was obtained and the modelling approach was extended to other types of produce. This showed the amenability of mechanical rollers to ensure full surface treatment of produce. Postharvest treatment of produce was carried using conventional low intensity UV sources principally emitting at 254 nm and also a commercially available high energy pulsed UV source. Treatment using the conventional UV source was carried out on mechanical rollers within a UV cabinet designed for this work at a fixed distance from the source and at an intensity of 1000 μW/cm2. A 5 minute conventional UV treatment of tomatoes was approximately comparable to fruit given a 3-pulsed treatment using the pulsed source (507 J/pulse of polychromatic light). The colour and texture of both groups of fruit were significantly maintained as compared with controls. The treated tomatoes also showed a significant increase in the ascorbic acid levels during storage. Similarly, a 15 minute conventional UV treatment of broccoli heads was comparable to heads given a 10-pulsed treatment using the pulsed source. Where both treatments gave rise to a statistically significant retention of green colour of treated broccoli. In addition, mangoes given a 10 minute conventional UV treatment were comparable to fruit given a 20-pulsed treatment using the pulsed source with both treatments leading to maintenance of texture as compared to control fruit. This confirmed the UV-hormetic effects. The effects of conventional and pulsed treatments are compared and discussed. Preharvest treatment of tomatoes and strawberries was carried out in commercial glasshouses. Doses of either 3 or 8 kJ/m2 were delivered to the fruits using a treatment device designed for the work, which delivered a combined intensity of 2000 μW/cm2 from two low pressure UV sources. The treated tomatoes showed a delay in development of colour as measured on the vine and after picking. Picked tomatoes were inoculated with P. digitatum and C. gloeosporioides and the results obtained showed a significant inhibition of the development of the fungi in the treated fruit during the storage period. These results suggest that the beneficial response shown by the preharvest treatment is not a localised one but a systematically induced resistance observable throughout the treated plant. This was shown by monitoring tomato fruits on treated plants which themselves where not directly exposed to the UV light. The two doses elicited different responses in the treated strawberries, with the 8 kJ/m2 dose causing the fruit to redden significantly faster than the 3 kJ/m2 treated fruits and controls. This could have significant nutritional benefit as the red colour of strawberries has been correlated with anthocyanin levels. On the other hand, treatment at the lower UV dose led to a lag in colour development. The amenability of the equipment utilised for commercial application is discussed.

A sinalização retrógrada mitocondrial é uma via de comunicação entre a mitocôndria e o núcleo que regula a expressão de uma série de genes nucleares que codificam proteínas mitocondriais, em resposta a disfunções mitocondriais. Em Saccharomyces cerevisiae, a via depende de Rtg1p e Rtg3p, que juntos formam o fator de transcrição que regula a expressão gênica, e de Rtg2p, um ativador da via. Aqui, nós mostramos novos estudos direcionados à investigação do impacto da sinalização retrógrada RTG-dependente na fisiologia mitocondrial. Verificamos que mutantes incapazes de realizar sinalização retrógrada RTG-dependente apresentam consumo de oxigênio mais elevado e menor produção de peróxido de hidrogênio em fase estacionária quando comparados a células selvagens. Interessantemente, mutantes RTG são menos capazes de decompor peróxido de hidrogênio assim como manter-se viáveis quando desafiados com peróxido. Nossos resultados indicam que a sinalização por RTG está envolvida na indução hormética de defesas antioxidantes e de resistência a estresse, função ainda não descrita para este sistema. / Mitochondrial retrograde signaling is a communication pathway between the mitochondrion and the nucleus which regulates the expression of a subset of nuclear genes that codify mitochondrial proteins, mediating cell response to mitochondrial dysfunction. In Saccharomyces cerevisiae, the pathway depends on Rtg1p and Rtg3p, which together form the transcription factor that regulates gene expression, and Rtg2p, an activator of the pathway. Here, we provide novel studies aimed at assessing the functional impact of the lack of RTG-dependent signaling on mitochondrial activity. We show that mutants defective in RTG-dependent retrograde signaling present higher oxygen consumption and reduced hydrogen peroxide release in the stationary phase when compared to wild type cells. Interestingly, RTG mutants are less able to decompose hydrogen peroxide as well as maintain viability when challenged with hydrogen peroxide. Overall, our results indicate that RTG signaling is involved in the hormetic induction of antioxidant defenses and stress resistance, a function of this system not yet described.

O melanoma é uma neoplasia maligna derivada de melanócitos, o qual tem uma letalidade elevada devido a sua característica altamente invasiva e agressiva. O caule da E. tirucalli produz um látex de coloração branca usado na medicina popular para o tratamento de neoplasias, que possui diversos constituintes ativos, incluindo o eufol, euforbol e isoeuforal. O objetivo do trabalho foi estudar os efeitos antineoplásicos in vitro e in vivo do látex da Euphorbia tirucalli em alguns modelos experimentais in vitro e in vivo. Células de melanoma B16/F10 foram tratadas com as seguintes diluições seriadas do látex a partir de uma concentração inicial de 0,1037ug/uL: 1/2, 1/4, 1/8, 1/16, 1/32, 1/64, 1/128, 1/256, 1/512, 1/1024, 1/2048, 1/5096, 1/11192. A viabilidade celular foi avaliada por MTT às 24, 48 e 72 horas. No experimento primeiro in vivo, células de melanoma foram inoculadas no tecido subcutâneo dorsal lombar de camundongos BALB/c e 10 dias após tratados, ou não, com 0,467ug/25g em volume de 200uL de látex de E. tirucalli por gavagem durante 14 dias. No segundo experimento, camundongos C57BL/6 foram inoculados com células de melanoma B16/F10 na veia da cauda para colonização pulmonar. No experimento in vitro, observou-se uma diminuição da viabilidade celular nas diluições de 1/1024 e 1/11192 no tempo de 24h e ás 48h houve uma diminuição da viabilidade celular nas diluições de 1/128, 1/256, 1/2048 e 1/11192. No experimento in vivo, observou-se que o látex da E. tirucalli foi capaz de reduzir o volume dos tumores subcutâneos em 53,5%, enquanto que o grupo não tratado o volume aumentou em 818,1%. No experimento de inoculação na veia da cauda com melanoma B16/F10 a administração de látex da E. tirucalli foi capaz de reduzir a fração de área pulmonar ocupada pelas colônias para 10,5% enquanto que no grupo não tratado, a fração de área pulmonar com colônias de melanoma aumentou para 35%. Não foram observadas alterações histopatológicas em nenhum dos grupos experimentais em outros órgãos. Os efeitos de redução de tumor, redução das colônias pulmonares e da viabilidade celular podem ser devidos à ação dos constituintes do látex que já demonstraram ter atividade antiproliferativa e citotóxica em outros experimentos, como o eufol e o euforbol. Embora o látex seja uma substância tóxica, ela pode ter tido, nas maiores diluições utilizadas, um efeito positivo para o tratamento do tipo hormesis / Melanoma is a malignant neoplasm derived from melanocytes, which has a high lethality due to its highly invasive and aggressive trait. The E. tirucalli stem produces a white latex used in folk medicine for the treatment of cancer, this product has several active constituents, including euphol, euphorbol and isoeuphoral. The objective of this work was to study the antineoplastic effects of Euphorbia tirucalli latex in experimental models in vitro and in vivo. B16/F10 melanoma cells were treated with the following serial dilutions of the latex from an initial concentration of 0.1037ug/?l: 1/2, 1/4, 1/8, 1/16, 1/32, 1/64, 1/128, 1/256, 1/512, 1/1024, 1/2048, 1/5096, 1/11192. Cell viability was assessed by MTT at 24, 48 and 72 hours. In the first in vivo experiment, melanoma cells were inoculated into the lumbar dorsal subcutaneous tissue of BALB/c mice and 10 days later they were treated or not treated with 0.467ug/25g of body weight in of 200?L of E. tirucalli latex by gavage for 14 days. In the second experiment, C57BL/ 6 mice were inoculated with B16/F10 melanoma cells into the tail vein for lung colonization. In the in vitro experiment, a decrease in cell viability at 1/1024 and 1/11192 dilutions was observed at 24h, and at 48h there was a decrease in cell viability at the dilutions of 1/128, 1/256, 1/2048 and 1/11192. In the in vivo experiment it was observed that the latex of E. tirucalli could reduce the volume of the subcutaneous tumors in 53.5% while in the untreated group the volume increased 818.1%. In the experiment of inoculation into the tail vein with B16/F10 melanoma cells, E. tirucalli latex administration was able to reduce the fraction of lung area occupied by the colonies to 10.5% whereas in the untreated group, the fraction of lung area with colonies was 35%. No histopathological changes were observed in any of the experimental groups in other organs. The effects of tumor reduction, reduction of lung colonies and cell viability may be due to the action of latex constituents that have already demonstrated antiproliferative and cytotoxic activity in other experiments, such as euphol and euphorbol. Although latex is a toxic substance, it may have developed, at the low dilutions used, a positive effect for the treatment of the hormesis type

Understanding how organisms function is central to Biology. Assessing how animals respond to fluctuations in their environment and determining inter-individual variation in phenotypic plasticity is paramount to identifying the physiology of traits, the selective pressures which have shaped them, and how we can manipulate them to benefit human life. The over-arching goal of my thesis is to understand the effects of sex, diet and pathogen exposure on the physiology of the fruit fly to assess the versatility of their individual traits in response to these natural factors. Chapter 2 investigates how the sexes utilise nutrition towards their lifespan and reproduction, providing evidence that the reproduction of males and females requires different dietary components while lifespan does not. Chapter 3 reveals that the sexes also differ in how they utilise nutrients for pathogen resistance identifying that females are highly protein-limited and more susceptible to infection than males. Chapter 4 provides the first comprehensive study of how organisms alter their dietary intake in response to infection, finding that flies behaviourally ingest less and consume higher protein:carbohydrate ratio diets when exposed to live fungal spores. Chapter 5 explores the phenomenon of trait-enhnacing external stresses, a response often termed hormesis. This study reveals that the beneficial physiological response from inactive fungal spore exposure, a potential form of hormesis, incurs immune costs. The implications of my results to the field of physiology are discussed in Chapter 6 where I also highlight the limitations of my work and potential consequences for life history research. Overall it is determined that studies investigating the natural physiological response of organisms or potentially beneficial treatments for our own species, must consider sex-specific effects, physiological consequences in a variety of traits, and how organisms may utilise variation within their environment to alter their phenotypic condition.

Many organisms can acclimate to new environments through phenotypic plasticity, a complex trait that can be heritable, be subject to selection, and evolve. However, the rate and genetic basis of plasticity evolution remain largely unknown. Experimentally evolved populations of the nematode Caenorhabditis remanei were created by selecting for stress resistance under different environmental conditions. This resource was used to address key questions about how phenotypic plasticity evolves and what the genetic basis of plasticity is. Here, I highlight ways in which a fuller understanding of the environmental context influences our interpretation of the evolution of phenotypic plasticity. In a population selected to withstand heat stress, an apparent case of genetic assimilation did not show correlated changes in global gene regulation. However, further investigation revealed that the induced plasticity was not fixed across environments, but rather the threshold for the response was shifted over evolutionary time. Similarly, the past environment experienced by populations can play a role in directing the multivariate response to selection. Correlated responses to selection between traits and across environments were examined. The pattern of covariation in the evolutionary response among traits differed depending on the environment in which selection occurred, indicating that there exists variation in pleiotropy across the stress response network that is highly sensitive to the external environment. To understand how the patterns of pleiotropy are altered by environment and evolution, there is a pressing need to determine the structure of the molecular networks underlying plastic phenotypes. Using RNA-sequencing, the structure of the gene regulatory network is examined for a subset of evolved populations from one environment. Key modules within this network were identified that are strong candidates for the evolution of phenotypic plasticity in this system. Together, the data presented in this dissertation provide a comprehensive view of the myriad ways in which the environment shapes the genetic architecture of stress response phenotypes and directs the evolution of phenotypic plasticity. Additionally, the structure of transcriptional network provides valuable insight into the genetic basis of adaptation to environmental change and the evolution of phenotypic plasticity. This dissertation includes both previously published and co-authored material.

The heat shock response (HSR) is the cell's molecular reaction to protein damaging stress and is critical in the management of denatured proteins. Activation of HSF1, the master transcriptional regulator of the HSR, results in the induction of molecular chaperones called heat shock proteins (HSPs). Transcription of hsp genes is promoted by the hyperphosphorylation of HSF1, while the attenuation of the HSR is regulated by a dual mechanism involving negative feedback inhibition from HSPs and acetylation at a critical lysine residue within the DNA binding domain of HSF1, which results in a loss of affinity for DNA. SIRT1 is a NAD+-dependent histone deacetylase that has been reported to deacetylate HSF1, thus promoting stress-induced HSF1 DNA binding ability and increasing HSP expression (Westerheide, Anckar et al. 2009). While an abundance of research is aimed to investigate SIRT1 substrate regulation, the mechanism in which SIRT1 itself is regulated is less understood (Haigis and Sinclair 2010). Positive and negative modulators of SIRT1 include AROS and DBC1, respectively, and have yet to be investigated in relation to SIRT1-dependent regulation of the HSR. In addition, metabolic stress such as caloric restriction has been shown to modulate SIRT1 activity in yeast (Rahat, Maoz et al. 2011), but the effect of caloric restriction on the HSR is unknown. Using cell-based assays, we have investigated how the HSR may be controlled by factors influencing SIRT1 activity. We found that heat shock results in an increase in the cellular NAD+/NADH ratio and an increase in recruitment of SIRT1 to the hsp70 promoter. Furthermore, we found that the SIRT1 modulators, AROS and DBC1, impact hsp70 transcription, HSF1 acetylation status, and HSF1 recruitment to the hsp70 promoter. The nematode Caenorhabditis elegans is a useful model organism for testing the relationship between the HSR and metabolism, as these animals can easily be calorically-restricted via bacterial limitation and possess the mammalian SIRT1 homolog, Sir2.1. Using C. elegans, we demonstrate that caloric restriction and heat shock have a synergistic effect on the HSR in a sir2.1-dependent manner. We show that caloric restriction increases the ability of heat shock to promote thermotolerance and fitness in wild-type animals and to preserve movement in a polyglutamine toxicity neurodegenerative disease model and that this effect is dependent on sir2.1. These studies provide insight into SIRT1-dependent regulation of the HSR and the impact of metabolism on this response. We highlight the SIRT1 modulators AROS and DBC1 as two new targets available for therapeutic regulation of the HSR and add caloric restriction as another HSR activator that can synergize with heat shock.

Submitted by Mariana Moreira Melero null (marianamelero@gmail.com) on 2016-05-02T15:13:06Z No. of bitstreams: 1 Mestrado_Mariana.pdf: 1132056 bytes, checksum: 67c296d4c37e6e143ec6bc3787d4d140 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-04T15:01:47Z (GMT) No. of bitstreams: 1 melero_mm_me_ilha.pdf: 1132056 bytes, checksum: 67c296d4c37e6e143ec6bc3787d4d140 (MD5) / Made available in DSpace on 2016-05-04T15:01:47Z (GMT). No. of bitstreams: 1 melero_mm_me_ilha.pdf: 1132056 bytes, checksum: 67c296d4c37e6e143ec6bc3787d4d140 (MD5) Previous issue date: 2016-03-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O Brasil encontra-se entre os maiores produtores mundiais de algodão. O objetivo deste trabalho foi verificar os efeitos da aplicação de subdoses dos herbicidas glyphosate, 2,4-D e paraquat em algodoeiro em condições de campo. Nos três anos agrícolas estudados (2010/2011, 2011/2012 e 2013/2014), foram instalados três ensaios, em cada ano, na Fazenda de Ensino, Pesquisa e Extensão, da Faculdade de Engenharia – Unesp, Campus de Ilha Solteira. O delineamento experimental empregado foi o de blocos ao acaso, com 6 tratamentos e 4 repetições, totalizando 24 parcelas para cada um dos ensaios. No primeiro ensaio, os tratamentos foram constituídos pela aplicação das subdoses do herbicida glyphosate, sendo: 0,0 (testemunha); 26,0; 52,0; 78,0; 104,0; e 130,0 g e.a. ha- 1; no segundo ensaio, os tratamentos foram constituídos pela aplicação das subdoses do herbicida 2,4-D, sendo: 0,0 (testemunha); 0,68; 1,36; 2,04; 2,72; e 3,40 g e.a. ha-1; E no terceiro ensaio, os tratamentos foram constituídos pela aplicação das subdoses do herbicida paraquat, sendo: 0,0 (testemunha); 4,8; 9,6; 14,4; 19,6; e 24,0 g i.a. ha-1. Para todos os ensaios, os produtos foram aplicados quando a cultura se encontrava no estádio B4. Observa-se que a produtividade de algodão em caroço aumentou até a subdose de 52 g e.a. glyphosate ha-1 no ano de 2010/11, não sendo observado tal efeito no ano 2011/12 e para o ano 2013/2014, houve um aumento de produção, porém não houve diferença estatística. No segundo ensaio, não houve diminuição na produtividade de algodão em caroço nos três anos de pesquisa e, no terceiro ensaio, a produtividade não sofreu interferência da aplicação, nos dois primeiros anos, para o terceiro ano, o paraquat apresentou resultados estatisticamente significativos, sendo a dosagem 24 g i. a. ha-1 a que apresentou maior incremento na produção em relação à testemunha. / The Brazil is among the largest producers of cotton. The objective of this study was to evaluate the effects of doses of application of glyphosate herbicide, 2,4-D and paraquat in cotton under field conditions. For all three crop years (2010/2011, 2011/2012 and 2013/2014), three essays have been installed and the experimental design was the randomized blocks, with 6 treatments and 4 repetitions, totaling 24 plots for each the tests. In the first experiment, the treatments were a combination of doses of glyphosate, as follows: 0.0 (control); 26.0; 52.0; 78.0; 104.0; and 130.0 g a.e. ha-1; in the second trial, the treatments consisted of the application of 2,4-D herbicide doses, as follows: 0.0 (control); 0.68; 1.36; 2.04; 2.72; and 3.40 g a.e. ha-1; And in the third test, the treatments were a combination of doses of the herbicide paraquat, as follows: 0.0 (control); 4.8; 9.6; 14.4; 19.6; and 24.0 g a.i. ha-1. The cotton productivity in core sub-dose increased to 52 g a.e glyphosate ha-1 in the year 2010/11, not being observed this effect in the year 2011/12 and for the year 2013/2014, an increase of production, but there was no statistical difference. In the second trial , there was no decrease in cotton productivity in seed in the three years of research and, the third test, productivity did not suffer application of interference in the first two years of study, for the third year, paraquat showed statistically significant results, the dosage being 24 g a.i.. ha-1 presented the highest increase in production compared to the control. / CAPES: 157840-1

Made available in DSpace on 2015-03-26T12:35:59Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1360029 bytes, checksum: 35b5c53d7d26fedd4a7b89866d26c3e0 (MD5) Previous issue date: 2012-05-31 / Fundação de Amparo a Pesquisa do Estado de Minas Gerais / Hormesis is a widely used in toxicology to describe the biphasic dose-response curve, where exposure to chemical or physical stress induces a stimulatory or inhibitory response dose-dependent. This phenomenon is typically described by a nonlinear dose-response where exposure to low levels of stress induces a stimulatory effect while high levels of exposure cause inhibition or toxicity. Two reparameterized logistic-logarithmic models were used to describe deltamethrin dose-response in Sitophilus zeamais, two insecticide-resistant strains and one insecticide-susceptible strain. Moreover, the profile of protein expression was examined in three populations. The biphasic dose-response was observed in three tested strains. It was observed several changes in protein profiling expression. In insecticide-resistant strains prevailed up-regulation protein expression (increase in spot volume) while in the insecticide-susceptible strain was observed down-regulation expression in most spots. This reduction may be due to a more extend refractory period and consequently greater delay in restoring the homeostatic state in the insecticide-susceptible strain. Few spots were identified as the expression of new proteins in the three strains. The Jacarezinho strain showed the largest number of protein spots, were six spots in the Jacarezinho strain, one spot in the Juiz de For a strain and no spot in the Sete Lagoas susceptible strain. This wide variation reflects the difficulty of relating the molecular events with the responses obtained in the dose-response curves. Although the biological responses can be observed with relative difficulty, the myriad of molecular events in response to changes in the environment make it extremely difficult to identify the mechanistic events involved in the stress response. The change in the profile of protein expression between populations reflects the difficulty in understanding the mechanisms involved in the hormesis. The exposure to even moderate doses of stress induces many changes in the profiling protein expression. In a next step the identification of differentially expressed proteins would be of great importance to check whether groups of common proteins among populations are affected. Besides the greater magnitude in population growth, moderate doses of deltamethrin resistant populations have a higher profile changes in protein expression and this behavior seems to be dependent on life history parameters. / Hormese é um termo amplamente utilizado na toxicologia para descrever o comportamento bifásico da curva dose-resposta, onde a exposição ao estresse físico ou químico induz uma resposta estimulatória ou inibitória dose-dependente. O fenômeno é caracteristicamente descrito por um modelo dose-resposta não-linear onde a exposição a baixos níveis de estresse induz um efeito estimulatório enquanto altos níveis de exposição provocam inibição ou toxicidade. Dois modelos logarítmico-logísticos reparameterizados foram utilizados para avaliar bioensaios dose-resposta em Sitophilus zeamais, duas populações resistentes e uma susceptível a inseticidas. Além disso, o perfil de expressão de proteínas foi analisado nas três populações. A curva dose-resposta foi bifásica para as três populações. Foi observado várias alterações no perfil de expressão de proteínas. Nas populações resistentes prevaleceu o aumento de expressão (aumento no volume do spot) enquanto na população susceptível foi observado redução de expressão na maioria dos spots diferencialmente expressos. Essa redução pode ser devido a um período refratário mais prologando nessa população e consequentemente maior retardo no restabelecimento do estado homeostático. Poucos spots foram identificados como expressão de novas proteínas nas três populações. A população de Jacarezinho foi a que apresentou o maior número de spots com expressão de novas proteínas, foram seis spots para população de jacarezinho, um spot para população de Juiz de Fora e nenhum spot na população susceptível de Sete Lagoas. Essa grande variação reflete a dificuldade de relacionar os eventos moleculares com as respostas obtidas nas curvas dose-resposta. Embora as respostas biológicas possam ser observadas com relativa dificuldade, a miríade de eventos moleculares em resposta as variações do ambiente tornam extremamente difícil identificar os eventos mecanisticos envolvidos com a resposta ao estresse. A variação no perfil de expressão de proteínas entre populações reflete a dificuldade para compreensão dos mecanismos envolvidos com o efeito hormético. A exposição mesmo a doses moderadas de estressse induziu muitas alterações no perfil de expressão de proteínas. Em uma próxima etapa a identificação das proteínas diferencialmente expressas seria de grande importância para verificarmos se grupos de proteínas comuns entre as populações são afetados. Além de apresentar maior magnitude no incremento populacional, em doses moderadas de deltametrina, as populações resistentes apresentam maior alteração no perfil de expressão de proteínas e esse comportamento parece ser dependente dos parâmetros de história de vida.

Orientador: Enes Furlani Junior / Resumo: O Brasil encontra-se entre os maiores produtores mundiais de algodão. O objetivo deste trabalho foi verificar os efeitos da aplicação de subdoses dos herbicidas glyphosate, 2,4-D e paraquat em algodoeiro em condições de campo. Nos três anos agrícolas estudados (2010/2011, 2011/2012 e 2013/2014), foram instalados três ensaios, em cada ano, na Fazenda de Ensino, Pesquisa e Extensão, da Faculdade de Engenharia – Unesp, Campus de Ilha Solteira. O delineamento experimental empregado foi o de blocos ao acaso, com 6 tratamentos e 4 repetições, totalizando 24 parcelas para cada um dos ensaios. No primeiro ensaio, os tratamentos foram constituídos pela aplicação das subdoses do herbicida glyphosate, sendo: 0,0 (testemunha); 26,0; 52,0; 78,0; 104,0; e 130,0 g e.a. ha- 1; no segundo ensaio, os tratamentos foram constituídos pela aplicação das subdoses do herbicida 2,4-D, sendo: 0,0 (testemunha); 0,68; 1,36; 2,04; 2,72; e 3,40 g e.a. ha-1; E no terceiro ensaio, os tratamentos foram constituídos pela aplicação das subdoses do herbicida paraquat, sendo: 0,0 (testemunha); 4,8; 9,6; 14,4; 19,6; e 24,0 g i.a. ha-1. Para todos os ensaios, os produtos foram aplicados quando a cultura se encontrava no estádio B4. Observa-se que a produtividade de algodão em caroço aumentou até a subdose de 52 g e.a. glyphosate ha-1 no ano de 2010/11, não sendo observado tal efeito no ano 2011/12 e para o ano 2013/2014, houve um aumento de produção, porém não houve diferença estatística. No segundo ensaio, não... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Brazil is among the largest producers of cotton. The objective of this study was to evaluate the effects of doses of application of glyphosate herbicide, 2,4-D and paraquat in cotton under field conditions. For all three crop years (2010/2011, 2011/2012 and 2013/2014), three essays have been installed and the experimental design was the randomized blocks, with 6 treatments and 4 repetitions, totaling 24 plots for each the tests. In the first experiment, the treatments were a combination of doses of glyphosate, as follows: 0.0 (control); 26.0; 52.0; 78.0; 104.0; and 130.0 g a.e. ha-1; in the second trial, the treatments consisted of the application of 2,4-D herbicide doses, as follows: 0.0 (control); 0.68; 1.36; 2.04; 2.72; and 3.40 g a.e. ha-1; And in the third test, the treatments were a combination of doses of the herbicide paraquat, as follows: 0.0 (control); 4.8; 9.6; 14.4; 19.6; and 24.0 g a.i. ha-1. The cotton productivity in core sub-dose increased to 52 g a.e glyphosate ha-1 in the year 2010/11, not being observed this effect in the year 2011/12 and for the year 2013/2014, an increase of production, but there was no statistical difference. In the second trial , there was no decrease in cotton productivity in seed in the three years of research and, the third test, productivity did not suffer application of interference in the first two years of study, for the third year, paraquat showed statistically significant results, the dosage being 24 g a.i.. ha-1 presente... (Complete abstract click electronic access below) / Mestre

Orientador: Paulo Mazzafera / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-17T19:01:38Z (GMT). No. of bitstreams: 1 DominguesJunior_AdilsonPereira_M.pdf: 2226269 bytes, checksum: 6e8a3f3315cad57c394a7eecc3145113 (MD5) Previous issue date: 2011 / Resumo: O glyphosate é considerado o herbicida mais utilizado em todo mundo. Seu mecanismo de ação baseia-se no bloqueio da rota do chiquimato, interrompendo a síntese dos aminoácidos aromáticos. Observa-se que a sua aplicação de maneira incorreta permite que uma parcela do ingrediente ativo chegue à cultura não-alvo, caracterizando a deriva. O café aparece como a segunda mais importante commodity no mercado internacional, com o Brasil como principal produtor. Neste trabalho, avaliou-se o impacto que o herbicida glyphosate teria na cultura de café, em uma condição de deriva simulada via pulverização foliar e via contaminação de três diferentes tipos de solos: argiloso, arenoso e rico em matéria orgânica. Análises revelaram que, em baixas concentrações, o glyphosate pode reduzir a taxa fotossintética do cafeeiro, mas estimular a síntese de pigmentos foliares. Também foi observado um aumento do conteúdo de compostos fenólicos, configurando-se como um possível caso de hormese. Quando aplicado nas folhas, o herbicida foi transportado para frutos em desenvolvimento. Nos frutos, o herbicida alterou o metabolismo de diversos compostos importantes para a bebida do café, tais como a cafeína e açúcares. Assim, este trabalho apresenta-se como um dos primeiros a investigar as alterações induzidas pelo herbicida glyphosate em plantas de café e a relatar a hormese provocada pelo herbicida sobre seus metabólitos secundários / Abstract: Glyphosate is the most widely used herbicide worldwide. Its mechanism of action is based on the blockage of the shikimate pathway, hindering the biosynthesis of the aromatic amino acids. Its incorrect application allows a portion of the active ingredient to reach the non-target crop, characterizing the drift. Coffee is the second commodity in the international market, and Brazil is the main producer. Here, we studied the impact that the herbicide glyphosate would have on coffee plants, in a condition where drifting was simulated by foliar sprays and contamination of three different soils: clay, sandy and rich in organic matter. Our data revealed that, at low concentrations, glyphosate may reduce photosynthesis, but it can stimulate the biosynthesis of leaf pigments. An increase of phenolic compounds was also observed, suggesting a possible hormesis effect. When applied to the leaves, the herbicide was transported to developing fruits and in the fruits the metabolism of important compounds for the coffee beverage, such as caffeine and sugar, was altered. Thus, this work presents itself as one of the first to investigate the impact of glyphosate herbicide on the coffee tree and report the hormesis caused by the herbicide on secondary metabolites of coffee / Mestrado / Biologia Vegetal / Mestre em Biologia Vegetal