Dissertations / Theses on the topic 'Pesticidal activity'

La fertilité, la pollution de l’écosystème sol sont devenues aujourd’hui des préoccupations etdes problèmes écologiques majeurs. L’objectif de cette étude est d’arriver à travers l’activitémicrobienne (hydrolyse de la FDA) et un large panel de 16 enzymes (phosphatases,hétérosidases, polysaccharidases, oligosaccharidases, oxydasses), à appréhender l’impact depolluants et d’amendement. Cinq sols aux caractéristiques physico-chimiques différentes ontété étudiés, et ont été soumis à différents traitements réalisés en microcosmes. Ces traitementsont porté sur l’ajout de zinc, cadmium, d’un herbicide, d’un insecticide, d’un fongicide, d’unnématicide et de fumier.L’expression des activités enzymatiques dépend fortement du type de sol. Ainsi lafraction limoneuse du sol jouerait un rôle crucial dans l’expression des enzymes telluriques. Parailleurs les résultats obtenus ont montré que des sols très proches d’un point de vu physicochimiquene le sont pas forcément au niveau enzymatique et microbien.L’ajout du fumier dans nos différents sols a entraîné quelque soit le type de sol defortes modifications positives des activités microbiennes et enzymatiques. L’effet stimulateurdu fumier sur l’activité microbienne et enzymatique dépend non seulement des paramètres dusol mais surtout de son activité initiale. Entre autre, l’impact positif du fumier est moinsmarqué dans les sols ayant des activités enzymatique ou des quantités de matière organiquefaibles. La tendance semble s’inversée concernant l’activité microbienne.L’impact des métaux lourds sur l’activité microbienne et les enzymes testées esttributaire des paramètres (argile, M.O), et de la nature des métaux lourds. Le cadmium s’avèreplus néfaste que le zinc. Si la majorité des activités enzymatiques sont diminuées par laprésence de métaux lourds d’autres en revanche ne sont pas impactées.La présence de pesticides dans nos sols révèle une grande disparité de résultat. Selon letype de sol, le type d’enzyme, une inhibition, un effet neutre ou bien une stimulation del’activité microbienne ou enzymatique par les pesticides ont été observés.Cette étude a permis de montrer que les enzymes sont très réactives aux différentesperturbations anthropiques quelque soit le type de sol considéré. Cependant cette réactivité setraduit par une très grande diversité des réponses. Cette diversité de réponse résulte d’ungrand nombre de paramètres liés aussi bien aux caractéristiques physico-chimiques quebiologiques du sol. Il n’a donc pas été possible de définir une enzyme ou groupe d’enzymesusceptible d’être utilisée comme indicateur pour l’ensemble des sols ou des traitements
Fertility and pollution of the soil ecosystem have become today’s concern and major ecologicalproblems. The objective ofthis study is to estimate through microbial activity (hydrolysis ofFDA) and a wide range of 16 enzymes (phosphatases, heterosidases, polysacchridases,oligosaccharidases, oxydase), the impact of pollutants and amendment in soil. The five soilsstudied are different regarding their physical and chemical characteristics. This soils are areexposed to different treatments in microcosms. These treatments consist to pollute our soilswith heavy metals (zinc, cadmium), pesticides (herbicide, insecticide, fungicide, nematicide)or to add manure.Our results showed that the expression of enzymatic activities depends on soil type.Thus, the silt fraction of soil plays a crucial role in this expression of soil enzymes. The soilswith physico-chemical characters are very similars, have not necessarily the same enzymaticprofile and expression or microbial activity.The presence of manure on our differents soils greatly increased the enzymatic andmicrobial activities. The stimulatory effect of manure depends on soil parameters but also theinitial enzymatic and microbial soil activities. The results showed that the positive impact ofmanure is less pronouncing in soils where the initial enzyme activity and organic matterquantity are low.The impact of heavy metals on microbial activity and enzymes tested depends on soilparameters (clay, organic matter, pH, ...) and nature of heavy metal. Cadmium is more toxicand longer decreases enzymatic and microbial activities than zinc. The presence of heavymetals in soils has reduced most of enzymes activity. Other enzymes are also unchanged orincreased by the pollutants.Soil pollution by pesticides show a large disparity and diversity of results. Dependingon soil type or the enzyme tested, the diffrents results showed an increase, neutral effect ordecrease by pesticides of enzymes and microbial activities.Watever the type of soil considered, this study has shown that soil enzymes are verysensitive and responsive to human disturbance. The reactivity of telluric enzymes is manifestedby a very large diversity of responses. Diversity responses of soil enzymes is depended tophysico-chemical characters and also soil biological parameters. In this study, it is verydifficult to define one or group of enzymes as a bioindicator for all soil disturbances

Objetivo: O principal objetivo desta pesquisa foi comparar os efeitos dos cultivos orgânico e convencional sobre as características físico-químicas, o teor de compostos antioxidantes, a atividade antioxidante e os resíduos de pesticidas de tomates cultivar Carmem. Considerando-se que o preparo doméstico de alimentos exerce efeitos expressivos sobre o nível de nutrientes em relação ao alimento in natura, particularmente no que tange ao teor de compostos antioxidantes e, conseqüentemente, na atividade antioxidante destes compostos, verificou-se também a influência de diversas formas de preparo doméstico para o consumo de tomates. Métodos: Os tomates foram submetidos aos seguintes tratamentos: inteiro, sem pele, sem semente, molho e purê de tomate. As amostras foram avaliadas físico-quimicamente quanto à atividade de água, sólidos solúveis totais, umidade, pH, cor, teor de ácido ascórbico, de fenólicos totais e de licopeno. As amostras foram liofilizadas e, posteriormente, submetidas ao processo de extração seqüencial para frutos, dando origem aos extratos etéreo, etanólico e aquoso. Aos extratos foram aplicados o teste do 1,1-difenil-2-picrilhidrazil (DPPH) e o sistema beta-caroteno/ácido linoléico para avaliação da atividade antioxidante in vitro. As amostras foram ainda submetidas à análise multirresíduos de pesticidas. Para análise estatística dos resultados utilizou-se análise univariada e o teste de Tukey, adotando-se um nível de significância de 5%. Resultados: O tomate orgânico inteiro e o molho apresentaram teores médios de ácido ascórbico maiores que seus similares convencionais. O tomate orgânico apresentou teor médio de fenólicos maior que o tomate convencional, para todos os produtos e preparações. Não foi possível identificar diferença entre orgânicos e convencionais quanto ao teor de licopeno, para todas as preparações e produtos avaliados. Para o extrato etéreo pelo método DPPH, verificou-se que apenas para o tomate sem semente, o orgânico apresentou atividade antioxidante maior que o convencional. Para o extrato alcoólico pelo método DPPH, apenas para o tomate sem semente não foram observadas diferenças entre orgânico e convencional. Para as demais preparações e produtos, o tomate orgânico apresentou percentual maior de atividade antioxidante que o convencional. No caso do extrato aquoso, apenas o tomate inteiro e o molho orgânico e convencional não apresentaram diferenças, para os demais modos de preparo (sem pele, sem semente e purê) o tomate orgânico apresentou percentual médio de atividade antioxidante maior que o tomate convencional. Para o extrato etéreo pelo sistema beta-caroteno/ácido linoléico, quando se comparou cultivo orgânico e convencional, observou-se que a atividade antioxidante do molho convencional foi maior que do molho orgânico. No entanto, para os tomates sem pele e sem semente, o orgânico apresentou valores médios significativamente maiores que aqueles obtidos para o tomate convencional. Para o extrato alcoólico pelo sistema beta-caroteno/ácido linoléico, não foram encontradas diferenças quando se compararam as preparações e os produtos provenientes do cultivo orgânico e convencional. No caso do extrato aquoso, o tomate orgânico apresentou maior média de atividade antioxidante para todos os modos de preparo, exceto para o molho. A forma de cultivo foi um fator determinante em relação à presença de resíduos de pesticidas (permetrina, tebuconazol e ditiocarbamatos), uma vez que o tomate orgânico preparado de diversas formas não apresentou tais resíduos. Conclusões: Devido ao limitado tamanho da amostra, nenhuma generalização pode ser estabelecida em relação ao tipo de cultivo e o valor nutricional dos tomates. No entanto, a partir dos resultados dos lotes de tomate avaliados, para a maioria dos parâmetros adotados, pode-se observar superioridade para o tomate orgânico em relação ao convencional.
Objective: The main objective of this survey was to compare the cultivation effect (organic and conventional) over the physical-chemical characteristics, the content of antioxidant compounds and the antioxidant activity of tomatoes Carmen cultivar. Considering that home preparation of the food may be a significant effect over the level of nutrients in relation to a fresh food, particularly in the content of antioxidants and, consequently, in the antioxidant activity of these compounds, the influence of many ways of home prepare of tomatoes was verified. Methods: Tomatoes underwent the following treatments: whole fresh tomatoes, fresh tomatoes without the peel, fresh tomatoes without seeds, tomato sauce and tomato puree. Samples were physical-chemically analyzed for water activity, total soluble solids, water content, pH, color, ascorbic acid, total phenolics and lycopene. Samples were freeze-dried, and then underwent the sequential extraction process for fruits, resulting in ether, alcohol and water extracts. These extracts were tested by DPPH test and the beta-carotene/linoleic acid system in order to evaluate the in vitro antioxidant activity. Samples were also submitted to pesticide multi residue analysis. For the statistical analyses, ANOVA and the Tukey test were used considering a significance level of 5%. Results: The whole organic tomato and the organic sauce presented higher acid ascorbic content than their conventional counterparts. The organic tomato exhibited higher phenolics content than the conventional for all products and preparations. It was not possible to detect differences between organic and conventional in relation to the lycopene content form all preparations and products. For the ether extracts by the DPPH method, it was verified that only the organic tomato without seeds showed higher antioxidant activity than the conventional one. For the alcohol extract by the DPPH method, only the tomato without seeds not reveal differences between organic and conventional. The remaining organic preparations and products were better than the conventional. In the case of the water extract, only the whole tomato and the sauce did not show differences between the organic and the conventional, whereas the other preparations of the organic tomato exhibited higher antioxidant activity than those of the conventional tomato. For the ether extract in the beta-carotene/linoleic acid system it was verified that the conventional sauce was better than the organic one. However, the organic tomatoes without peel and seeds exhibited higher antioxidant activity than the conventional ones. For the alcohol extract in the beta-carotene/linoleic acid system no difference was detected between the organic and conventional tomato preparations and products. In the case of the water extract, the organic tomato afforded higher antioxidant activity for all types of preparations, except for the sauce. The method of cultivation was a determinant factor in relation to the presence of pesticides residues, since the organic tomato prepared in different forms did not contain these residues (permethrin, tebuconazol and dithiocarbamate). Conclusions: Due the limited size of the sample, no general statement could be made in relation to the method of cultivation and the nutritive value of tomatoes. However, for most of the parameter studied, the organically grown tomatoes ranked higher than the conventional tomatoes.

Epidemiological evidence suggests that many human cancers may be attributed to environmental factors. Since the number of chemicals introduced into the environment is increasing at an alarming rate, measures must be taken to reduce human exposure. There is thus a growing need for the development of relevant and sensitive procedures for monitoring human exposure to environmental carcinogens and mutagens. The objective of this thesis was to evaluate the feasibility of using urine analysis to monitor individual exposure to pesticides. Pesticides are widely used chemicals in agriculture, and some are known to possess genotoxic properties. In this study, urine samples were collected from 21 orchardists (all non-smokers) in the Okanagan Valley when they were engaged in the application of pesticides during the fruit growing seasons in 1984 and 1985. As controls, urine was collected from these same individuals during the pre-spraying as well as the post-spraying seasons. In addition, 18 individuals from an agricultural research station in the Okanagan region (including 16 non-sprayers and 2 sprayers) were recruited to provide urine samples during the same time periods as the orchardists. As controls outside the fruit growing region, individuals from Vancouver and Grand Forks, B.C. were recruited to provide one urine specimen for this study. The urine samples were concentrated by reversed-phase high pressure liquid chromatography and then tested for their ability to induce chromosome aberrations (i.e., clastogenic activity) in cultured Chinese hamster ovary (CHO) cells. Furthermore, an attempt was made to examine the exfoliated urothelial cells for the presence of micronuclei as a potential in vivo indicator of damage by genotoxic constituents in the urine. Urine samples obtained from the orchardists 16 to 24 hours after pesticide application in 1984 resulted in levels of clastogenic activity undistinguishable from normal control limits. The failure to demonstrate increased clastogenic activity in the urine may have been due to (1) exposure to pesticides below the detection limits of the procedure, (2) the lack of genotoxicity in the agents sprayed, and (3) rapid pesticide metabolism and excretion in the urine. In the follow-up study of 1985, all urine voids were collected on the evening of the day of pesticide spraying (i.e., within 8 hours of exposure). Using this sampling protocol, the assay results showed that (1) urine samples collected from the orchardists and the agricultural research station workers during the non-spraying periods revealed no significant difference in clastogenic activity compared to the reference control group from Vancouver and Grand Forks, and (2) clastogenic activity of urine samples collected during the spraying period in 1985 was significantly elevated for the orchardist group (P<0.001; Tukey's non-parametric multiple comparisons test) but not for the agricultural research station personnel. The high urinary clastogenic activity found for the orchardists was attributed to heavy exposure to pesticides during the mixing, formulation and application process and the lack of compliance by the sprayers to wear full protective gear in hot weather. Cigarette smoking was another factor affecting urine clastogenicity together with pesticide exposure. Cigarette smokers from Grand Forks and the Okanagan agricultural research station demonstrated significantly higher urinary clastogenic activity than non-smokers (P<0.001; Mann-Whitney U test) . No dose-response relationship between the number of cigarettes smoked and urinary clastogenic activity was evident for the group of smokers assayed. All of the above effects were obtained without metabolic activation in vitro, suggesting that the clastogenic agents in the urine were direct-acting. In a large proportion of the urine samples tested, low but significant (relative to solvent controls) levels of clastogenic activity were observed in the urine of unexposed non-smokers, indicating the role of other factors in the appearance of urine clastogenicity. Urinary pH and creatinine did not differ among the study groups. No data were obtained from the analysis of micronuclei in exfoliated urothelial cells. The scarcity of cells among the subjects made it difficult to determine the frequency of micronucleated urothelial cells. On the basis of the present research, the monitoring of urine samples for genotoxicity appears to be a useful tool for assessing human exposure to environmental carcinogens and mutagens. Urine analysis is not only valuable in qualitatively demonstrating exposure to genetically hazardous agents, but is also a promising procedure for assessing the efficacy of preventive measures which are implemented to reduce further exposure.
Medicine, Faculty of
Pathology and Laboratory Medicine, Department of
Graduate

This thesis describes research investigating the side-effects of pesticides on soil microbial biomass and microbial activity, with particular reference to two recently developed pesticides, a fungicide, epoxiconazole, and a herbicide, quinmerac. In a dose-responsee xperiment,a pplication of thesep esticidest o a sandy loam soil, at up to 10 and 20 times field rate, had no significant effect on soil microbial biomass C or ninhydrin-reactive N, over 84 days incubation. There was also no effect on soil respiration, except for the higher rate quinmerac-treated soil, which evolved 13% lessC02-Cthan the control. The rate of mineralisation of epoxiconazole and quinmerac, and their long-term effect on soil respiration, were measured in three contrasting soils: a sandy loam, a silty clay loam, and a clay soil, using 14C -labelled active ingredients. The kinetics of the pesticides' mineralisation were quite different, epoxiconazole being hyperbolic, while quinmerac was sigmoidal. The maximum amount of mineralisation of both pesticides occurred in the silty clay loam soil, which had the lowest microbial biomass content. The mineralisation of the pesticides was increased by the addition of ryegrass, with the greatest effect in the silty clay loam soil, probably because of the large ryegrass C: biomass C ratio. The mineralisation of epoxiconazole was affected by the ryegrass amendment much more than quinmerac. Further additions of the pesticides had no significant effect on soil respiration or pesticide mineralisation. The mineralisation of epoxiconazole and quimnerac was further investigated in the silty clay loam soil, using samples with different crop management histories, and the effects of ryegrass and glucose amendment. Pesticide mineralisation was shown to be related to the amount of soil microbial biomass, indicating that the difference in mineralisation rate between the three soil types above was not due to differences in their crop management, but innate differences in soil chemistry and microbiology. Ryegrass addition stimulated the mineralisation of epoxiconazole more than quinmerac, while the reverse was true for glucose, indicating that the pesticides were being degraded by two distinct fractions of the microbial biomass. The effects of long-term cumulative field application of the pesticides benomyl, chlorfenvinphos, aldicarb, triadimefon and glyphosate, on soil microbial biomass and mineralisation of soil organic matter were investigated. The addition of aldicarb consistently increased the microbial biomass, due to its beneficial effect on crop growth, but this effect was not reflected in the rate of organic matter mineralisation. However, in general, the continued application of these pesticides for up to 19 years, at slightly higher than the recommended rates, had very little effect on the soil microbial population. The effects of epoxiconazole and triadimefon on soil ergosterol content and microbial biomass C were compared in a sandy loam soil. Both pesticides temporarily reduced soil ergosterol by about 30%, while biomass C remained largely unaffected. However, when straw was added to the soils, the inhibition of ergosterol was still evident, as was an inhibitory effect on biomass C. The measurement of soil ergosterol was more sensitive to the pesticide effects than biomass C, and could be a useful test in determining changes in fungal populations.

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A produção orgânica é um sistema que permite alcançar bons níveis de produtividade, evitando ao mesmo tempo os riscos de contaminação química do agricultor, dos consumidores e do meio ambiente. Pelo fato da planta de jambu ser bastante utilizada como medicamento alternativo e por indústrias de cosméticos, vem aumentando o interesse devido às suas características físico-químicas. No entanto, as pesquisas sobre essa cultura ainda são muito incipientes. Existem poucos trabalhos e uma insuficiente diversidade de análises físico-químicas que possam caracterizar e diferenciar os tipos de cultivo em relação ao jambu. Assim, o objetivo do presente estudo foi analisar o óleo essencial e os compostos antioxidantes em diferentes partes de jambu (folha e inflorescência) cultivado sob adubação orgânica e mineral, além de caracterizar os minerais no solo e nas plantas, nos diferentes tipos de cultivo. O experimento foi conduzido na Fazenda Experimental São Manuel (São Manuel-SP), pertencente à Faculdade de Ciências Agronômicas - UNESP, campus de Botucatu) e na mesma época. O delineamento estatístico foi em blocos casualizados em esquema fatorial (2 x 6), duas fontes de adubação (orgânica e mineral) e seis doses de esterco de curral e uréia, com quatro repetições para todas as análises efetuadas, exceto para as características de potencial antioxidante e espilantol, que foram utilizadas três repetições. Os experimentos realizados apresentaram como tratamentos seis doses de adubação mineral (0, 30, 60, 90, 120, 150 g m-2 de uréia), aplicadas parceladas em duas vezes e seis doses de adubação orgânica (0, 2, 4, 6, 8 e 10 kg m-de esterco de curral), aplicadas no plantio. As características avaliadas foram teores de nutrientes na parte aérea, altura de plantas, massa fresca e seca, composição química do óleo essencial, teor de acido ascórbico; potencial...
The organic production it is a system that will achieve good levels of productivity, while avoiding the risk of chemical contamination of farmers, consumers and the environment. Because the plant jambu be widely used as alternative medicine and cosmetic industries, has been increasing interest due to their physical and chemical characteristics. However, the researches on this crop are still very incipient. There is little work and an insufficient variety of physical and chemical analysis that can characterize and differentiate the types of cultivation on the jambu.The purpose of this study was to analyze the essential oil and the antioxidant compounds in different parts of jambu (leaf and inflorescence) grown under organic and mineral fertilizer, and characterize the minerals in soil and plants in different types of cultivation. The experiment was conducted led in (Experimental Farm São Manuel (São Manuel-SP), belonging to the Faculty of Agricultural Sciences - UNESP, campus of Botucatu) and at the same time. The statistical design was factorial (2 x 6), two sources of fertilizer (organic and mineral) and six doses of the kraal manure and urea, with four replications for all analysis performed, except for the characteristics of potential antioxidant and spilantol, which were used three repetitions. The experiments presented treatments as six doses of conventional fertilization (0, 30, 60, 90, 120, 150 g m-2, urea), applied in two split doses of fertilizer and six non-conventional (0, 2, 4, 6, 8 and 10 kg m-2 of the kraal manure), applied at planting. The characteristics were nutrient content in shoot, plant height, fresh and dry weight, chemical composition of essential oil, ascorbic acid content, antioxidant potential, and presence of pesticides. The results show that the compounds were present in this study were trans-caryophyllene, germacrene D, L-dodecene and espatulenol and... (Complete abstract click electronic access below)

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The highest standard of human activity is associated to agricultural and industrial activities. Thus, aquatic sediments are the most used environmental files to evaluate anthropogenic contamination from atmosphere, soil and water, due to its adsorption capacity. Inadequate and uncontrolled use of pesticides has happened in order to increase agricultural yield, although it brings forth pollution problems and serious consequences for public health. Therefore, further surveillance has been required concerning pesticides’ use and sale as well as the environment monitoring. Thus, this study aimed at evaluating Pelotas River regarding its sediment quality and taking into account compounds such as orangiochloride and organophosphorous to determine the ecological risk, spatial and temporal distributions. For this purpose, sediment samples were collected in 8 points (6 into Pelotas River and 2 into Tributaries), whose collections were carried out quarterly. This trial covered the four hydrological seasons of the year, totaling four collections that were registered with Peterson dredger. The methodology used to determine the studied pesticides was QuEChERS. The p'p'-DDT is worth mentioning from the organochlorines, since it was found in all samples. This represents that it was observed in 53.23% of the contaminated samples, with 0.158 ppb as maximum value. While Isodrin has shown the highest organochlorine concentration - 0.502 ppb. The points PEL 05 and TRI 02 showed the highest representativeness of contamination by organochlorines, caused by the slope degree of the area and by agricultural portion of each part. Methyl parathion recorded the highest representativity, with 48.4% of the total contaminated samples for organophosphates, with 2.42 ppb as maximum concentrations, while Disulfoton showed the highest concentration of this class - 2.62 ppb. The organochlorines have not shown any ecological risk. But, for organophosphates, the maximum concentration of Disulfoton pesticide has indicated a risk coefficient with significant potential for adverse effects on organisms. In the spatial and temporal distributions for organochlorines, there was some predominance of those compounds at PEL 05, PEL 04 and TRI 02 points, whereas for orgnaphosphates, points such as PEL 00, PEL 02, PEL 04 and PEL 05 were predominant. In temporal distribution, for organochlorines, eight from the ten compounds were distributed in summer, seven of them during autumn and springtime. In organophosphates, the four quantified pesticides were recorded only during autumn month. However, in springtime, three of them were representative, but in summer and winter, only two of these compounds were observed. Consequently, since Pelotas River is a Class I river, it is evident that concentrations of both classes of the studied pesticides cannot be neglected. Organophosphates are much toxic, much volatile, more used as well as the most representative ones in concentrations and they also present an ecological risk. Besides, there is an evident need to monitor these compounds in soil, sediment, water and biota, so that there is sustainability concering its use and application, aiming at improving the environmental quality and preservation of this natural resource, in this case named as Pelotas River.
O ápice da atividade humana está vinculado às atividades agrícolas e industriais, e os sedimentos aquáticos são os arquivos ambientais mais usados para a avaliação da contaminação antropogênica, oriunda da atmosfera, do solo e da água, devido a sua capacidade de adsorção. A utilização inadequada e desenfreada de agrotóxicos ocorre a fim de se aumentar a produtividade agrícola, todavia, gera problemas de poluição e consequências graves à saúde pública. Logo, são necessárias maiores fiscalizações no uso e venda desses compostos e monitoramento no ambiente. Portanto, objetivou-se avaliar a qualidade do sedimento do rio Pelotas levando em consideração a contaminação por compostos oragnoclorados, organofosforados, para determinar o risco ecológico e a distribuição espacial e temporal. Com essa finalidade, foram coletadas amostras de sedimentos em oito pontos (6 no rio Pelotas e dois em Tributários) com coletas realizadas trimestralmente. O experimento abrangeu as quatro estações hidrológicas do ano, com um total de quatro coletas efetuadas com a draga Peterson. A metodologia utilizada para determinação dos pesticidas foi a do QuEChERS. Dos organoclorados, merece destaque o p’p’-DDT, encontrado em todas as coletas, o qual representa 53,23% das amostras contaminadas, com valor máximo de 0,158 ppb. Enquanto o Isodrin apresenta a maior concentração dos organoclorados - 0,502 ppb. Os pontos PEL 05 e TRI 02 apresentam maior representatividade de contaminação por organoclorados, acarretados pelo grau de declividade do terreno e pela porção agrícola de cada área. Dos organofosforados, o Methyl parathion obteve maior representatividade com 48,4% do total das amostras contaminadas, com concentrações máximas de 2,42 ppb, enquanto o Disulfoton apresentou a maior concentração dessa classe - 2,62 ppb. Os organoclorados não apresentaram risco ecológico, mas, para os organofosforados, a concentração máxima do pesticida Disulfoton indica coeficiente de risco com potencial significativo de efeitos adversos aos organismos. Na distribuição espacial e temporal para os organoclorados, houve predominância dos compostos nos pontos PEL 05, PEL 04 e TRI 02 e, para os orgnafosforados, os pontos PEL 00, PEL 02, PEL 04 e PEL 05 foram considerados predominantes. Na distribuição temporal, para os organoclorados, dos dez compostos, oito se distribuíram no verão, sete no outono e primavera. Nos organofosforados, os quatro pesticidas quantificados foram encontrados apenas no mês de outono. Todavia, no mês da primavera, três deles foram representativos, mas, no verão e no inverno, apenas dois desses compostos foram encontrados. Dessa maneira, fica evidente, sendo o rio Pelotas de Classe I, que as concentrações de ambas as classes dos pesticidas estudados não podem ser negligenciadas, haja vista os organofosforados serem os mais tóxicos, mais voláteis, os mais usados, também os mais representativos em concentrações além de apresentarem risco ecológico. Ademais, evidencia-se a necessidade de monitoramento desses compostos no solo, sedimento, água e biota, a fim de que haja sustentabilidade no uso e aplicação, visando ao melhoramento da qualidade ambiental e à preservação desse recurso natural, que é o rio Pelotas.

Resumo: A produção orgânica é um sistema que permite alcançar bons níveis de produtividade, evitando ao mesmo tempo os riscos de contaminação química do agricultor, dos consumidores e do meio ambiente. Pelo fato da planta de jambu ser bastante utilizada como medicamento alternativo e por indústrias de cosméticos, vem aumentando o interesse devido às suas características físico-químicas. No entanto, as pesquisas sobre essa cultura ainda são muito incipientes. Existem poucos trabalhos e uma insuficiente diversidade de análises físico-químicas que possam caracterizar e diferenciar os tipos de cultivo em relação ao jambu. Assim, o objetivo do presente estudo foi analisar o óleo essencial e os compostos antioxidantes em diferentes partes de jambu (folha e inflorescência) cultivado sob adubação orgânica e mineral, além de caracterizar os minerais no solo e nas plantas, nos diferentes tipos de cultivo. O experimento foi conduzido na Fazenda Experimental São Manuel (São Manuel-SP), pertencente à Faculdade de Ciências Agronômicas - UNESP, campus de Botucatu) e na mesma época. O delineamento estatístico foi em blocos casualizados em esquema fatorial (2 x 6), duas fontes de adubação (orgânica e mineral) e seis doses de esterco de curral e uréia, com quatro repetições para todas as análises efetuadas, exceto para as características de potencial antioxidante e espilantol, que foram utilizadas três repetições. Os experimentos realizados apresentaram como tratamentos seis doses de adubação mineral (0, 30, 60, 90, 120, 150 g m-2 de uréia), aplicadas parceladas em duas vezes e seis doses de adubação orgânica (0, 2, 4, 6, 8 e 10 kg m-de esterco de curral), aplicadas no plantio. As características avaliadas foram teores de nutrientes na parte aérea, altura de plantas, massa fresca e seca, composição química do óleo essencial, teor de acido ascórbico; potencial... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The organic production it is a system that will achieve good levels of productivity, while avoiding the risk of chemical contamination of farmers, consumers and the environment. Because the plant jambu be widely used as alternative medicine and cosmetic industries, has been increasing interest due to their physical and chemical characteristics. However, the researches on this crop are still very incipient. There is little work and an insufficient variety of physical and chemical analysis that can characterize and differentiate the types of cultivation on the jambu.The purpose of this study was to analyze the essential oil and the antioxidant compounds in different parts of jambu (leaf and inflorescence) grown under organic and mineral fertilizer, and characterize the minerals in soil and plants in different types of cultivation. The experiment was conducted led in (Experimental Farm São Manuel (São Manuel-SP), belonging to the Faculty of Agricultural Sciences - UNESP, campus of Botucatu) and at the same time. The statistical design was factorial (2 x 6), two sources of fertilizer (organic and mineral) and six doses of the kraal manure and urea, with four replications for all analysis performed, except for the characteristics of potential antioxidant and spilantol, which were used three repetitions. The experiments presented treatments as six doses of conventional fertilization (0, 30, 60, 90, 120, 150 g m-2, urea), applied in two split doses of fertilizer and six non-conventional (0, 2, 4, 6, 8 and 10 kg m-2 of the kraal manure), applied at planting. The characteristics were nutrient content in shoot, plant height, fresh and dry weight, chemical composition of essential oil, ascorbic acid content, antioxidant potential, and presence of pesticides. The results show that the compounds were present in this study were trans-caryophyllene, germacrene D, L-dodecene and espatulenol and... (Complete abstract click electronic access below)
Orientador: Giuseppina Pace Pereira Lima
Coorientador: Rumy Goto
Banca: Márcia Ortiz Mayo Marques
Banca: Atila Francisco Mogor
Mestre

Pesticides have been used to control various types of pests, including plants and insects, for thousands of years, however the impact of exposure to these toxic chemicals, with respect to environmental and health consequences, is not fully understood. Two pesticides of interest, molinate and dieldrin, have been shown to cause neurotoxicity in humans, but their mechanisms of toxicity are still unknown. In order to better understand how exposure to these chemicals can cause toxicity, the structure-activity relationship (SAR) was defined to determine how specific changes to the structure of each pesticide affects the toxicity profiles of each of these compounds. Results of this study demonstrated that oxidation of molinate to molinate sulfoxide, and then further to molinate sulfone, a more potent inhibitor of aldehyde dehydrogenase. The sulfone metabolite is capable of covalently modifying the active-site cysteine residue of aldehyde dehydrogenase, accounting for the observed enzyme inhibition. These results indicate that the compound responsible for the toxicity from molinate exposure is not the parent compound, but rather one of the sulfoxidation metabolites. When the SAR of dieldrin was investigated with respect to a Parkinson's disease model, it was determined that the compounds that were previously found to be the least potent insecticides were the most toxic with respect to dopaminergic cells. Each of the compounds tested was observed to disrupt dopamine metabolism in accordance with their toxicity profiles in dopaminergic cells. In combination, these results implicate important structural features responsible for the toxicity with respect to Parkinson's disease. This information is critical for the development of new pesticides, and will be important to increase the selective toxicity for insects while minimizing adverse/off-target effects. This can lead to the development of safer, more effective pesticides that will be essential for future environmental and human health.

The aim of the thesis entitled “Synthesis and biological activity evaluation of natural products and their analogues” is to synthesize some natural products and their analogues in order to study SAR and evaluate their biological activity as fungicides or herbicides. The thesis reports the first enantioselective synthesis of crassinervic acid in 12 steps and 11.8% overall yield. Crassinervic acid, recently isolated from leaves of Piper crassinervium by Kato and co-workers, shows high antifungal activity mainly against Cladosporium cladosporioides and Cladosporium sphaerospermum (minimum amount required for the inhibition of fungal growth on TLC: 0.5 microg). Crucial steps for our synthetic strategy included an enantioselective Sharpless epoxidation of easily available geraniol, followed by a regioselective reduction of the corresponding epoxyalcohol, and a condensation of the monoterpene fragment with lithiated 4-hydroxymethylphenol. The successful coupling of the two moieties required an accurate choice of the protecting groups. On the basis of the developed strategy, the absolute configuration of the compound was assigned as (S). A short and efficient synthesis of racemic Crassinervic acid was also carried on and applied to the preparation of analogues. All the synthesized compounds were successively tested for antifungal activity and SAR studies were developed. Synthetic efforts towards Ascaulitoxin were also carried on. Ascaulitoxin, a new unusual phytotoxic bis-aminoacid N-glucoside, was isolated from the culture filtrate of Ascochyta caulina (P. Karst.) v.d. Aa and v. kest, the causal agent of leaf and stem necrosis of Chenopodium album (also known as lambsquarter or fat hen, a common world-wide weed of many arable crops such as sugar beet and maize), a promising microherbicide for the biological control of this common noxious weed. The proposed route is concise and modular, making it convenient for large scale preparation. Finally, an approach towards the synthesis of Harzianic acid was developed. This compound is a new antimicrobial antibiotic from a Trichoderma harzianum strain which was isolated for the first time in 1994 by Sawa et al.. Very recently Vinale et al., reported its isolation, absolute configuration and antifungal as well as plant growth promoting activity. Harzianic acid showed antifungal activity against Pythium irregulare, Sclerotinia sclerotiorum, and Rhizoctonia solani. The synthesis is now at a final stage.

L'auteur a essaye tout au long de ce travail, de realiser une analogie structurale avec des acides amines en synthetisant divers acides aminoboroniques, diversifiant les substituants portes par l'atome d'azote et en modifiant la distance azote-bore, en vue d'une etude structure-activite phytosanitaire. Apres un bref apercu sur l'activite biologique que presentent les acides boroniques et plus specialement les acides aminoboroniques, il rapporte dans un premier chapitre les differents essais d'obtention d'acides -aminoboroniques. Le deuxieme chapitre est centre sur la synthese d'acides -aminoboroniques par reaction d'hydroboration. Une etude prealable de l'hydroboration d'amines allyliques avec divers substituants de l'atome d'azote est effectuee. L'acces aux acides b-aminoboroniques par reaction d'hydroboration fait l'objet du troisieme chapitre. Des intermediaires de structures enamines ont donc ete synthetises par voie photochimique

En Afrique Sub-Saharienne, les problématiques de contamination de la ressource en eau par les pesticides et les résidus pharmaceutiques commencent à être mises en évidence. La problématique de la thèse porte sur la caractérisation de l’impact des activités humaines sur la qualité de la ressource en eau, par l’étude de la contamination par les pesticides et les résidus pharmaceutiques. Le site d’étude choisi est le bassin versant de la Méfou, qui draine la capitale du Cameroun, Yaoundé. Dans un premier temps, le site est caractérisé par ses spécificités environnementales (relief, occupation des sols) et sociodémographiques afin d’identifier les pressions anthropiques. Les pratiques d’agriculture urbaine, et en particulier le maraîchage intensif dans les bas-fonds entraîneraient l’utilisation massive de pesticides. L’absence d’assainissement efficace et les multiples latrines, drains et fosses septiques constitunt autant de sources diffuses de contamination par les résidus de médicaments. En prenant le cas des pesticides, une méthode cartographique a permis de confirmer l’hypothèse selon laquelle les parcelles agricoles pourraient être identifiées comme des sources de pollution diffuses de pesticides via le ruissellement. La méthode multicritère SIRIS-Pesticides de l’INERIS (Institut National de l’Environnement Industriel et des Risques) appliquée sur deux scénarios de pratiques agricoles indique un potentiel transfert des pesticides ciblés vers les eaux de surface. Afin de conforter ces hypothèses, deux diagnostics de pollution ont été réalisés entre 2015 et 2018 en saisons pluvieuses, couplant des méthodes d’échantillonnages ponctuels et passifs. Une liste de 32 pesticides et de 24 résidus pharmaceutiques a été recherchée dans les eaux de surface et les eaux souterraines du bassin de la Méfou. Les résultats généraux indiquent (i) de fortes concentrations en herbicides et en anti-inflammatoires non stéroïdiens ainsi que la détection et la quantification d’une large gamme de composés recherchés, (ii) une contamination bien plus marquée en milieu urbain qu’en milieu péri-urbain, (iii) un risque environnemental à ces concentrations pour deux herbicides (diuron et atrazine) et (iv) la contamination de certains points d’eau souterraine (forages, puits, sources) par les résidus pharmaceutiques. Une enquête sociologique réalisée autour des points d’eau de prélèvement a permis d’identifier les enjeux liés à l’utilisation de cette ressource en eau. La contamination des eaux souterraines pourrait entraîner une exposition potentielle des populations aux résidus pharmaceutiques présents dans leur eau de boisson. Les résultats principaux constituent donc une base d’information sur les pressions anthropiques, les niveaux de contamination et les enjeux liés à l’eau à Yaoundé. Ils soulèvent des questionnements sur (i) les transferts des pesticides et des résidus médicamenteux dans l’hydrosystème de la Méfou, et (ii) à propos de l’exposition et des risques sanitaires potentiels posés par leur occurrence et leurs niveaux de contamination dans la ressource en eau
Demographic growth and urbanization create pressure on water resources. Among urban contaminants, pesticides and pharmaceuticals can be discharged into the aquatic environment through agricultural activities and untreated waste waters. Their presence is also reported in global water bodies. Measured contamination levels can have ecotoxicological effects on aquatic organisms as well as on human populations. In Sub-Saharan Africa, these problems are beginning to be highlighted. Local agricultural practices and consumption of pharmaceuticals lead to specific concerns.The aim of this thesis is to identify and characterize the impacts of human activity on the quality of the water resource in urban Sub-Saharan Africa, by analyzing pesticide and pharmaceutical contamination. The study area was the Méfou watershed that drains the political capital of Cameroon, Yaoundé (Center Region).First, the study area was characterized by its environmental (reliefs, land use) and socio-demographic specificities to identify anthropogenic pressures. Urban agricultural practices and in particular the intensive market gardening in the humid lowlands involves the use of massive amounts of pesticides. The absence of a sewage system and the numerous pit-latrines, drains and septic tanks are the sources of diffuse pharmaceutical contamination.Using the example of pesticides, a contaminated runoff mapping method based on susceptibility maps (from the IRIP method) confirmed that some treated plots located in situations that favor runoff were sources of diffuse pesticide contamination. Several areas in the study basin can accumulate this polluted runoff. Next, the multi-criteria SIRIS-Pesticides method from INERIS was applied based on two agricultural scenarios constructed with data sources from the literature. Results pointed to the potential transfer of pesticides from crops to both surface and groundwater.To reinforce these hypotheses, two water quality surveys were conducted in the rainy season between 2015 and 2018, combining grab and passive sampling. Thirty-two pesticides and twenty-four pharmaceuticals were searched for in surface and groundwater in the Méfou watershed. The main results indicate that (i) high concentrations of herbicides and analgesics were detected and quantified in the water samples along with a wide range of targeted compounds; (ii) the contamination pattern showed that the urban area is more polluted than the peri-urban area of Yaoundé; (iii) the measured concentrations pose an environmental risk, in particular the herbicides atrazine and diuron; and (iv) some groundwater sampling points used for drinking water were contaminated by the targeted pharmaceuticals.A social survey conducted in March 2018 around the sampling points identified the risks related to water use. The lack of a sewage system and the discharge of untreated waste water into the immediate surroundings facilitate contamination of the sampling sites. As groundwater is used as an alternative to the tap water network in Yaoundé, the population is also exposed to the risk of pharmaceutically contaminated drinking water.The main results provide baseline information about anthropogenic pressures, contamination levels and related issues in Yaoundé. They raise questions about (i) the transfer of contaminants in the Méfou hydrosystem and (ii) population exposure and potential health risks due to their presence and to the levels of contamination of the water resources

Résumé : Cette thèse porte sur le rôle de deux expositions environnementales encore peu étudiées et pouvant influer sur l’incidence des hémopathies malignes (HME) de l’enfant : les rayons ultraviolets (UV) et les pesticides liés aux activités agricoles.Les leucémies (LA) et lymphomes de l’enfant sont les deux types principaux de HME et représentent respectivement environ 470 et 200 nouveaux cas par an en France. Leur prise en charge thérapeutique et leur survie ont fait d’immenses progrès, cependant la connaissance de leurs facteurs de risque est encore très partielle.Les études sur les effets des UV dans les cancers de l’enfant sont peu développées. Plusieurs méta-analyses récentes concluent à une augmentation du risque de LA chez l’enfant lors d’une exposition professionnelle ou domestique de la mère aux pesticides pendant la grossesse. L’exposition aux pesticides d’origine agricole a été moins étudiée, et les résultats sont hétérogènes.La première partie, écologique, de ce travail s’intéresse à l’exposition résidentielle aux UV. Une étude a été réalisée à partir des observations du Registre National des Hémopathies malignes de l’Enfant (RNHE) faites sur une longue période, entre 1990-2009 et sur l’ensemble de la France métropolitaine (9 082 cas de LA et 3 563 cas de lymphomes). Les données de l’exposition aux UV résidentiels étaient issues de la base EUROSUN. Une moyenne quotidienne d’exposition aux UV résidentiels sur l’ensemble de la période 1988-2007 à l’échelle communale a été considérée. Une augmentation significative de l’incidence des leucémies aiguës lymphoblastiques à précurseurs B (LAL-Pré B) chez les moins de 5 ans a été observée avec l’exposition aux UV résidentiels au moment du diagnostic. L’association n’était pas modifiée après une stratification par périodes ; par tranches d’unités urbaines ; par grandes régions, et par un indice de défaveur français. Une deuxième étude, individuelle, sur les UV ne trouvait pas de modification de l’association en prenant en compte le rôle de facteurs individuels soupçonnés d’être associés aux LAL et en regardant l’exposition à la naissance. Les données individuelles de ces facteurs provenaient de deux études cas-témoins en population générale, l’enquête ESCALE (2003-2004) et l’enquête ESTELLE (2010-2011).La dernière partie de la thèse se penche sur l’exposition résidentielle aux pesticides liés aux activités agricoles. Cette étude s’appuie sur les données du RNHE, recueillant 10 994 cas de LA et 4 301 cas de lymphomes sur la période 1990-2013. L’intensité de l’activité agricole dans le canton de résidence au moment du diagnostic a été choisie comme proxy de l’exposition aux pesticides. Cette intensité a été à partir des données cantonales du Recensement général Agricole de 2000. Dans cette première approche aucune association n’a été mise en évidence entre les HME et la part de Surface Agricole Utile (SAU) totale. Les analyses par grands types de cultures montrent, dans cette première approche, une association positive et significative entre l’intensité de cultures en oléagineux et l’incidence des LAL Pré-B et des lymphomes de Burkitt. Des analyses de sensibilité montraient des résultats hétérogènes par période d’étude
Abstract: This thesis deals with the role of two environmental exposures not much studied and that could have an impact on the incidence of childhood hematological malignancies (CHM): ultraviolet radiation (UV) and agricultural pesticides.The two major diagnostic groups are acute leukemia (AL) and lymphomas and represent respectively around 470 and 200 new cases per year in France. Despite the progress made in improving therapeutic caring and survival, the etiology of these cancers remains largely unknown.There are very few studies on the association between UV and these cancers. Meta-analyses found a coherent association between childhood AL and parental professional or domestic pesticides exposure during pregnancy. However the association with residential exposure to agricultural pesticides has been less studied and results are heterogeneous.The first, ecological, part of the thesis addressed the associations between residential UV exposure at diagnosis and the incidence of types and subtypes of CHM in France. The 9,082 cases of acute leukemia (AL) and 3,563 cases of lymphoma diagnosed before the age of 15 years from 1990 to 2009 were provided by the French National Registry of Childhood Hematological Malignancies. UV data from 1988 to 2007 were extracted from the EUROSUN database. The annual daily average UV exposure of the children estimated at the municipalities of residence was considered. There was a significant increase in precursor B-cell acute lymphoblastic leukemia (PBC-ALL) in children aged less than 5 years with residential exposure to UV. The results remained stable in analyses stratifying by deprivation index or degree of urbanization of the municipalities.A second, individual, study found no change in the association between UV and PBC-ALL after taking into account the influence of suspected individual risk factors for ALL, and evaluated this association at birth. Individual data were collected by interviews in the ESCALE (2003-2004) and ESTELLE (2010-2011) nationwide case-control studies.The last part of this work focused on the residential exposure to agricultural pesticides. The 10,994 cases of AL and the 4,301 cases of lymphomas diagnosed among children less than 15 years old were obtained from the French National Registry of Childhood Hematological Malignancies over the period 1990-2013. Intensity of agricultural activities by Canton was used as a proxy of residential agricultural pesticides exposure. This proxy was estimated from the 2000 French agricultural census data. At this first step of the analysis, no associations were found between total agricultural area and incidence of CHM. Analyses by types of crops showed, at this first step, a significant association between oilseeds and PBC-ALL and Burkitt lymphoma. Sensitivity analyses evidenced heterogeneous results by time period

L'objet de ce travail a ete d'explorer l'interet des approches multivariees non lineaires en chimiometrie et plus particulierement de la cartographie non lineaire en agrochimie afin de fournir de nouveaux outils statistiques efficaces et facilement accessibles pour analyser les donnees physico-chimiques et biologiques. Apres avoir examine les methodes multivariees lineaires classiques et les principes generaux de l'analyse graphique, nous avons etudie les fondements des methodes multivariees non lineaires, les possibilites de leurs exploitations graphiques et leurs utilisations en agrochimie. Ainsi, les reseaux neuronaux ont ete utilises pour modeliser la demi-vie des pesticides. La comparaison avec l'analyse factorielle discriminante a montre la superiorite de l'approche non lineaire. Nous avons entrepris une etude theorique approfondie de la cartographie non lineaire. Elle a permis de souligner ses avantages et inconvenients en chimiometrie mais egalement de definir les axes de recherche a developper afin d'optimiser son utilisation en agrochimie. Differents parametres statistiques ont ete developpes afin d'estimer les contributions de chaque point a l'erreur totale de la carte et a l'information contenue dans celle-ci. L'analyse graphique des cartes non lineaires a permis de resoudre les problemes d'exploitation des resultats inherents au processus iteratif de la methode et d'interpreter ces cartes en termes de relations de type structure-activite et structure-propriete. Plusieurs exemples d'application ont ete traites afin de montrer les potentialites de cette methode en agrochimie et de souligner son aspect complementaire vis-a-vis des analyses multivariees lineaires classiques

Thesis (MSc)--Stellenbosch University, 2002.
ENGLISH ABSTRACT: Food demands for the ever-increasing human population is increasing the pressure on the agricultural sector to produce more food. In order to satisfy these demands, farmers are turning to chemical biocides for the control of pest species to produce greater crop yields. All pesticides must be toxic or poisonous to the target species they intend to control. Unfortunately, most pesticides are toxic or poisonous to non-target organisms as well, with detrimental effects on their health. Organic farming was developed to enhance the overall health of the farm's natural soilmicrobe- plant-animal biodiversity. No synthetic fertilisers and/or pesticides are used when farming organically. Life in the soil consists of intricate food webs and interactions between the soil dwelling invertebrates. The soil-organisms are divided into three main groups, viz., Micro-organisms (e.g. protozoa, bacteria and fungi) mesofauna (nematodes, Collembola and Acari) and macro-fauna (e.g. millipedes, isopods, insects, molluscs and earthworms). The invertebrates are very susceptible to chemical contamination by chemical biocides in natural and agro-ecosystems. The soil invertebrate communities are responsible for the decomposition of organic material in soil, thereby remineralising the soil. The decomposition processes start with comminution of the large pieces of organic material by meso- and macro-fauna and ends with the micro-fauna and microbial organisms that complete these processes by returning the nutrients in an inorganic form to the soil. The aim of this study was to investigate whether, and to what extent the soil organisms are influenced by different management practices viz., organic management practices versus conventional management practices. A vineyard on the farm Plaisir de Merle, in Simondium, Western Cape was used for the present study. One half of a one hectare vineyard was managed organically and the other half conventionally. Within each vineyard block six different treatments were performed. Three of the treatments were strictly organic and the other three were strictly conventional. Four replicates of each management treatment were performed. The bait-lamina technique was used to assess the feeding activity of the soil organisms exposed to the different management treatments. In addition to the bait-lamina trials in the vineyard itself, bait-lamina tests were performed in microcosm studies with soil from the organically and conventionally managed vineyard blocks under controlled conditions. In order to assess the impact of the various pesticides that are used in the vineyards in the conventional way, on the soil fauna, standard acute toxicity tests and behavioural tests were performed on Eisenia fetida, the compost worm. The bait-lamina tests in the vineyard revealed that the moisture content of the soil plays an important role in the biological activity of soil fauna. The different management treatments did affect the biological activity of the soil fauna, but seasonal changes also proved to be one of the important factors governing biological processes in the soil. The acute toxicity tests showed that the active ingredients (mancozeb, penconazole and trifloxystrobin) of three of the pesticides that were tested in this study, had negatively affected E. fetida at their recommended application concentrations. The remaining two pesticides' active ingredients (glyphosate and N-acetyl salicylic acid) did not affect the earthworms negatively at the recommended application concentrations. The preference behavioural trials showed that E. fetida could detect and avoid contaminated substrates at the LCso-concentrations of the different pesticides. All the earthworms were influenced positively in the preference behaviour experiments. Because of certain limitations of the bait-lamina technique, it was difficult to formulate conclusions on what happens in the soil. A possible explanation for the differences in feeding activity of soil fauna could be attributed to the migration of the soil fauna to more habitable soil horizons during the dry summer conditions, when most of the pesticides are applied. The ecological relevance of the acute toxicity tests conducted need to be investigated further. It is clear that the acute toxicity tests provided important information that should be considered, but care should be taken and the necessary safety factors be determined and considered when doing risk assessment studies. The results of the preference behaviour studies showed that for certain pesticides E. fetida can be a sensitive bioindicator of acute and/or sub-acute lethal toxicity testing but this might not necessarily be the case for other pesticides. The goal of doing laboratory studies is to gain as much information to make reliable extrapolations to field situations from laboratory data. Laboratory-to-field extrapolations are very complicated because of the physico-chemical composition of soil, the unpredictable way pesticides behave within soil and the reaction of soil organisms to the soil and to the chemical biocides that are used. Further studies need to be done in order to fully understand to what extent the soil fauna were affected by the different management practices applied to the vineyard at Plaisir de Merle.
AFRIKAANSE OPSOMMING: Voedsel aanvraag vir die toenemende menslike bevolking plaas groot druk op die landbou sektor om meer kos te produseer. Om aan die voedsel eise te voldoen, gebruik boere al meer chemiese biosiede om pesspesies te bestry. Alle pestisiede moet toksies of giftig wees vir die teiken organisme waarvoor dit bestem is. Ongelukkig is die meeste pestisiede ook toksies of giftig vir nie-teiken organismes, wat tot nadelige effekte op hul gesonheid kan lei. Organiese boerdery is ontwikkel om die algehele gesondheid van die plaas se natuurlike grond-mikrobe-plant-dier biodiversiteit te bevorder. Geen sintetiese bemestingstowwe en/of pestisiede mag gebruik word wanneer daar organies geboer word nie. Die lewe in die grond bestaan uit ingewikkelde voedselwebbe en interaksies tussen die grondlewende invertebrate. Die grond invertebrate word verdeel in drie hoof groepe, nl. mikro-organismes (bv. Protozoa, bakterieë en fungi) meso fauna (Nematoda, Collembole en Acari) en makrofauna (bv. Millipoda, Isopoda, Insecta, Mollusca en erdwurms). Die Invertebrata is die mees vatbaarste vir chemiese kontaminasie deur chemiese biosiedes in natuurlike en landbou ekosisteme. Die grond invertebraat gemeenskappe is verantwoordelik vir die afbreek van alle organiese materiaal in die grond en dus vir remineralisering van die grond. Die afbreekproses begin by die komminusie van groter stukke organiese materiaal deur die meso- en makrofauna en eindig met die mikrofauna en mikrobes wat die prosesse voltooi deur die nutriente terug te plaas in die vorm van anorganiese produkte in die grond. Die doel van hierdie studie was om te ondersoek of, en tot watter mate, grond organismes geraak word deur verskillende grondbestuurspraktyke, nl. Organiese grondbestuurspraktyke teenoor die konvensionele grondbestuurspraktyke. 'n Wingerd op die plaas Plaisir de Merle, in Simondium, Wes-Kaap, was gebruik vir die huidige studie. Een helfte van 'n een hektaar wingerd is organies bestuur en die ander helfte is op die konvensionele manier bestuur. Op elk van die twee wingerd blokke is ses verskillende behandelings toegepas. Drie van die behandelings was streng organies en die ander drie was streng konvensioneel van aard. Vier replikate van elke behandeling is toegepas op elk van die twee wingerdblokke. Die bait-lamina metode is gebruik om die voedingsaktiwiteit van die grond organismes te asses seer. As toevoeging tot die bait-lamina proewe in die wingerd self, is bait-lamina toetse ook in mikro-kosmosse in die laboratorium gedoen met grond afkomstig vanaf die twee wingerdblokke. Om die impak van die verskillende pestisiede op die grondorganismes te ondersoek, is standaard akute toksisteitstoestse en gedragstoetse uitgevoer met die komposerdwurm, Eisenia fetida. Die bait-lamina resultate in die wingerd het getoon dat die voginhoud van die grond die belangrikste rol speel wat die biologiese aktiwiteit van die grondorganismes beïnvloed. Die verskillende behandelings het die biologiese aktiwiteit van die grond fauna geaffekteer, maar seisoenale veranderings is ook uitgesonder as een van die bepalende faktore wat die biologiese prosesse in die grond stuur. Die akute toksisiteitstoetse het getoon dat die aktiewe bestandeie van drie van die pestisiede (mancozeb, penconazole en trifloxystrobin), E. fetida negatief beïnvloed het teen die aanbeveelde konsentrasies wat toegedien is. Die aktiewe bestandeie van die ander twee pestiede (glyphosate en N-asetiel sallisiel suur) het nie die erdwurms nadelig beïnvloed teen die aanbeveelde konsentrasies wat toegedien is nie. Die gedragsproewe het getoon dat E. fetida die LCso-konsentrasies van al die verskillende pestisiede kan waarneem en vermy. Al die erdwurms is positief beïnvloed in die gedragseksperimente met die verskillende pestisiede. Omdat die bait-laminametode sekere beperkings het, was dit moeilik om tot gevolgtrekkings te kom oor wat presies in die grond gebeur. 'n Moontlike verklaring vir die verskillende voedingsaktiwiteite van die grond fauna kan toegereken word aan die migrasie van die grondorganismes na meer leefbare grondhorisonne gedurende die droë somer toestande, wat toevallig met die spuit van die meeste pestisiede ooreenstem. Die ekologiese relevansie van die akute toksisiteitstoetse wat uitgevoer is, moet meer deeglik ondersoek word. Die belangrikheid van die akute toksisteitstoetse is duidelik en het waardevolle informasie gelewer, maar sorg moet geneem word, en die nodige veiligheids faktore moet bepaal word en in ag geneem word, wanneer riskobepalingstudies gedoen word. Die gedragsproewe het getoon dat vir sekere pestisiede E. fetida 'n sensitiewe bioindikator van akute en/of sub-akute letale toksisiteits toetse kan wees, maar nie noodwendig vir ander pestisiede nie. Die doel van laboratoriumstudies is om so veel as moontlik inligting te versamelom vertroubare ekstrapolasie te kan maak na situasies in die veld vanaf laboratorium data. Laboratorium-na-veld ekstrapolasies is dikwels baie gekompliseerd as gevolg van die fisies-chemiese samestelling van die grond, die onvoorspelbare manier waarop chemiese pestisiede met die grond reageer en die reaksie van die grondorganismes op chemiese biosiede in die grond. Verdere studies moet gedoen word om so deeglik maanlik die mate van die impak wat die verskillende bestuurspraktyke op die grond fauna het, te verstaan op Plaisir de Merle.

L?utilisation de produits phytosanitaires est à l?origine d?un problème majeur à l?interface de l?agriculture et de la préservation des ressources en eau. Dans ce contexte, les effets de différents métaux (Cu, Zn), métalloïdes (As) et pesticides (Azimsulfuron, Oxadiazon, Prétilachlore, Fipronil et Alphacyperméthrine) ont été étudiés en terme de biodisponibilité voire de toxicité sur des algues d?eaux douces (Pseudokirchneriella subcapitata et Chlorella sp.) sensibles aux pollutions diffuses d?origine agricole, en prenant en compte l?influence des ligands naturels et l?impact d?une multipollution. L?étude de la relation potentielle entre spéciation, biodisponibilité et toxicité a été menée, sur trois sites d?étude associés à une pollution d'origine agricole. Des échantillons d'eaux, collectés dans des canaux de drainage et des rizières (pollution organique), de drainage prélevés sur des parcelles soumises ou non à des épandages de lisiers de porcs (Cu, Zn) et de ruissellement issus de parcelles viticoles (multipollution) ont été caractérisés et analysés. Les résultats de toxicité ont été confrontés avec ceux mesurés sur des solutions standards en conditions contrôlées et les résultats analytiques ; dosage de résidus de pesticides et des métaux et métalloïdes traces. L?analyse d?échantillons non toxiques menée conjointement, après additions de Cu, par biotests et DPASV a permis d?approfondir les relations entre la toxicité et les espèces électrochimiquement labiles détectées. Elle a souligné la présence de complexes labiles du cuivre (CuL), responsables de la toxicité. Les études de laboratoire et de terrain illustrent de la complexité de l'évaluation de l'exposition dans des contextes de multipollution, chaque molécule nécessitant une évaluation spécifique de son comportement et de ses effets dans un milieu donné. Par ailleurs, les divers produits phytosanitaires présents sont susceptibles d'interagir entre-eux (toxicité de mélanges complexes) et avec les ligands naturels (complexation).

El biochar, el carbón especial obtenido a través del proceso de pirólisis de la biomasa, se ha propuesto como un medio de captura de carbono a través del suelo. También se ha considerado útil para mejorar algunas de las propiedades pertinentes del suelo y para reducir los efectos adversos de los contaminantes. Pero el uso de biochar debe garantizar, además de su conservación, que no genere efectos adversos en los organismos vivos, en las funciones ecosistémicas del suelo, o sobre los sistemas naturales adyacentes. Esta tesis pretende contribuir al conocimiento en este sentido, mediante el estudio de: -La capacidad del biochar para proteger la materia orgánica más lábil del suelo; -Los efectos adversos causados por el biochar una vez incorporado en el suelo, en función del tipo de proceso de pirólisis y las dosis aplicadas; y -La modulación de los efectos secundarios tóxicos de algunos pesticidas cuando se incorporan a los suelos que han recibido un aporte de biochar Para alcanzar estos objetivos, se utilizaron tres tipos de biochar producidos a partir de la misma biomasa (astillas de madera de pino) como enmienda del suelo: biochar producido por pirólisis lenta (PL), el obtenido por pirólisis rápida (PR) y el obtenido a través de la gasificación de la biomasa (PG). La adición de biochar genera cambios en la estructura y la biología del suelo, sea por la modificación positiva o negativa de su equilibrio físico y biológico. Considerando que la comunidad microbiana juega un importante papel regulador en el suelo, condicionando las reacciones bióticas más importantes, la biomasa microbiana y su actividad respiratoria se utilizaron como indicadores de los efectos producidos por la adición de biochar. Se han usado modelos de adsorción que se han utilizado para evaluar la capacidad del biochar para adsorber y proteger la materia orgánica más lábil del suelo. Se disenó un experimento factorial completo para comprobar los efectos de tres factores individuales (biochar, nutrientes y adición de glucosa) y su relación con la mineralización de la materia orgánica del suelo. Los resultados de este trabajo indicaron que cada tipo de biocarbón estableció diferentes interacciones con el suelo. El ensayo ecotoxicológico sugirió que el biochar de pirólisis rápida (PR) es el menos recomendado si se utiliza en dosis superiores a la ED50 calculada. No se obtuvo evidencia de interacciones de protección de materia orgánica lábil, como la glucosa, por nuestros resultados. Aunque la glucosa fue absorbida con eficacia en el suelo tratado con biochar, la absorción no actuó como un mecanismo de protección a largo plazo contra la mineralización. El biochar producido por la pirólisis lenta o por gasificación, PL y PG, resultaron los más recomendables desde el punto de vista de la respuesta de la biomasa microbiana. Sobre la base de estos resultados, PL fue el biochar elegido para evaluar si la aplicación de tres plaguicidas podía tener efectos adversos detectables sobre la actividad microbiana del suelo, y para evaluar si la adición de biochar modifica la toxicidad o los efectos adversos de estas sustancias químicas en el suelo. La modulación de los efectos producidos por estas sustancias químicas ha quedado demostrada. Estos resultados remarcan cómo diferentes biochars ejercen diferentes interacciones con el suelo, en función de sus características físico-químicas intrínsecas. En esta tesis se hace hincapié en la importancia de futuros trabajos centrados en la formulación de directrices para la aplicación de biochar en el suelo.
Biochar, the particular charcoal obtained through the process of pyrolysis of biomass, has been proposed as a mean of carbon sequestration through soil. It has been also considered useful to improve some relevant properties of the soil fertility and to reduce adverse effects of pollutants. But the use of biochar must ensure, in addition to its conservation, that it does not generate adverse effects on living organisms, on the soil ecosistemic functions, or on the adjacent natural systems. This thesis attempts to contribute to knowledge in this regard, by studying: - The biochar's ability to protect the most labile soil organic matter; - The hypothetic adverse effects caused by biochar once incorporated into the soil, depending on the type of pyrolysis process and doses applied ; and - The modulation of the toxic side effects of some pesticides when incorporated into soils that have received a provision of biochar. To achieve these goals three types of biochars produced from the same starting biomass (pine wood chips) were used to amend soil: biochar produced by slow pyrolysis (PL), biochar obtained from fast pyrolysis (PR) and biochar obtained through the gasification of biomass (PG). The addition of biochar results in changes of the structure and biology of the soil, then in positive or negative modification of its physical and biological balance. Considering that microbial community plays a major regulatory role in the soil, conditioning the most important biotic reactions, microbial biomass and soil respiration were used as indicators of the effects produced by the addition of biochar into the soil. Sorption models were used to assess the ability of biochar to adsorb and protect the most labile soil organic matter. A fully factorial experiment was designed to check the effects of three single factors (biochar, nutrients and glucose addition) and their relationship with the whole SOM mineralization. The results of this work demonstrated that each kind of biochar established different interactions with the soil.

Les pesticides utilisés pour protéger les plantes des insectes nuisibles constituent une menace pour les organismes non cibles tels que les vers de terre. En raison de leur activité de bioturbation de sol, les vers de terre sont en contact direct avec les particules et les micro-organismes du sol, ainsi qu'avec les polluants, notamment les pesticides. L‘objectif de ce travail est d‘étudier (1) l‘effet d‘un organophosphoré (OP) «éthyl-parathion» sur la sensibilité de deux espèces de vers de terre endogés, Aporrectodea caliginosa et Allolobophora chlorotica; et (2) le rôle du microbiote intestinal, en synergie avec les voies de détoxification du ver de terre, dans la tolérance ou la détoxification des pesticides. Dans la première partie, les réponses biochimiques et comportementales ont montré que A. caliginosa est plus sensible à l'exposition à «l‘éthyl-parathion» que A. Chlorotica. Les résultats portent sur l‘analyse de biomarqueurs physiologiques (poids), biochimiques (AChE, CbEs, GST) et comportementaux (production de turricules et activité de creusement). Nous avons montré que la sensibilité de A. caliginosa semble liée à la sensibilité intrinsèque de l‘AChE à «l‘éthyl-parathion». De plus, le rôle des carboxylestérases, capables de piéger les insecticides OP, ainsi que le rôle de détoxification des GST notamment, ne semblaient pas être des mécanismes efficaces impliqués dans la tolérance de A. chlorotica. Dans la deuxième partie, nous avons caractérisé, en présence ou non d‘insecticide, le microbiote dans le sol ingéré, les turricules et les intestins des 2 vers de terre. Nos résultats ont montré des différences dans la composition microbienne de ces compartiments. A cet égard, nous avons suggéré que chacune de ces espèces hébergent un microbiote spécifique de l‘espèce dans leur intestin. Nos résultats ont notamment montré que l‘intestin du ver de terre agit comme un «filtre biologique» pour les communautés microbiennes ingérées lors du passage dans l‘intestin. A ce niveau, nous avons identifié, au niveau bactérien, quatre genres dominants dans l'intestin de A. caliginosa et deux genres dominants dans l'intestin de A. chlorotica. Nous avons notamment identifié une souche de Rhodococcus, très abondante dans l'intestin de A. chlorotica. Des études ont montré que des souches de Rhodococcus peuvent dégrader certains groupes de pesticides. Nous suggérons que la présence de cette souche pourrait contribuer à la tolérance de A. chlorotica. Enfin, nous avons montré que l‘effet de l‘éthyl-parathion sur les activités enzymatiques du sol dépend principalement de la texture du sol et non pas de la présence et/ou de l‘espèce de ver de terre.Selon nos conclusions, il est extrêmement important d'inclure plus d'une espèce pour évaluer la toxicité des insecticides organophosphorés, en raison des différences interspécifiques pouvant se produire au sein d'une même catégorie écologique. De plus, l'identification et l'analyse fonctionnelle des micro-organismes présents au niveau de l‘intestin et susceptibles d'intervenir dans la détoxication des pesticides permettraient d‘améliorer nos connaissances sur le devenir du pesticide dans l'organisme et pourraient constituer un outil important dans les programmes de bioremédiation
Pesticides used to protect plants from pests, threat grievously non-target organisms such as earthworms. Due to their feeding and burrowing activities, earthworms are in direct contact with soil particles and microorganisms, as well as pollutants including pesticides. This work investigated (1) the effect of an organophosphate “ethyl-parathion” on the sensitivity of two endogeic earthworms’ species, Aporrectodea caliginosa and Allolobophora chlorotica; and (2) the role of the gut-microbiota, in synergy with the earthworm’s detoxification pathways, in pesticide tolerance or detoxification. In the first part, biochemical and behavioral responses showed that A. caliginosa is more sensitive to “ethyl-parathion” exposure than A. chlorotica. The endpoints measured ranged from physiological (weight), biochemical (AChE, CbEs, GST) to behavioral biomarkers (cast production and burrowing activity). Our findings showed that the sensitivity of A. caliginosa could be mainly due to the intrinsic sensitivity of its AChE to “ethyl-parathion”. The role of the carboxylesterases, acting as bioscavenger of OP, and the role of the detoxifying enzymes GST did not appear to be efficient mechanisms involved in A. chlorotica tolerance. In the second part, we aimed to characterize the microbiome within the ingested soil, the cast and the gut tissue of A. caliginosa and A. chlorotica in control or polluted soils. Our results showed differences in the microbial composition between these compartments. In this line, we suggested that these two earthworms’ species harbor a species-specific microbiome in their gut. In particular, our findings showed that the earthworm’s gut acts as a “biological filter” for ingested microbial communities during the gut passage. At the level of the gut, we identified four dominated genus within the gut of A. caliginosa versus two dominated genus in the gut of A. chlorotica. Notably, we identified a Rhodococcus strain, which is highly abundant in the gut of A. chlorotica. Previous studies reported Rhodococcus strains for their ability to degrade some group of pesticides. We suggest that the presence of this strain could contribute to the tolerance of A. chlorotica. Finally, we showed that the effect of ethyl-parathion on soil enzyme activities mainly depend on soil texture rather than the presence and/or the species of earthworms. According to our findings, it is of considerable importance to include more than one species to assess toxicity from organophosphorus insecticides, due to the interspecific differences that can occur within the same ecological category. Moreover, the identification and the functional analysis of the microorganisms found in the earthworm’s gut and able to intervene in pesticide detoxification could enhance our knowledge about the fate of the pesticide inside the organism, and could be an important tool for bioremediation program

La diminution de la pollution des eaux par les pesticides constitue l'enjeux environnemental majeur de la Martinique au début du 20ème siècle. Dans ce cadre est proposée l'analyse de l'organisation spatiale des activités agricoles à l'origine de la variabilité spatiale de la charge polluante. L'appréhension de plusieurs niveaux d'organisation spatiale, selon trois points de vue sur l’espace, apporte une connaissance de la complexité du système rural. Cette approche conceptuelle se concrétise par l’utilisation de trois outils : les Systèmes d’Informations Géographiques (SIG), la modélisation graphique (chorèmes) et les Systèmes multi - agents (SMA), au moyen desquels sont exploitées les données issues d’enquêtes auprès des exploitants. Cette démarche est appliquée sur un territoire rural de 1200 hectares situés sur la rive gauche de la Capot, caractérisée par l'exclusivité des activités agricoles et la présence de 46 exploitations. Plusieurs points sont -soulignés : la construction historique- de l'espace martiniquais ; la répartition de logiques de gestion de l'espace ; la distribution des orientations culturales et des systèmes de cultures calqués en partie sur celle de types de fonctionnement spatial d’exploitations. Les conséquences environnementales sont évaluées à travers un indicateur de contribution des parcelles à la pression polluante : systèmes de culture et orientation culturales constituent les principaux critères de différenciation spatiale. Des simulations multi - agents confirment par ailleurs I hypothèse du rôle majeur de l'aménagement foncier dans la mise en œuvre de pratiques minimisant les épandages de pesticides
This study shows how the spatial organization of agricultural activities is at the origin of polluting loads distribution. In order to understand the complexity of the rural system in which the various activities take place, an approach was necessary which would consider several levels of space organization, according to three points of view on space: As a result, three tools have been used at once : geographic information systems (GIS), graphic modeling (chorèmes) and-multi-agents systems (MAS) used to analyse data resulting from farmer's interviews. These tools are applied to a rural territory of 1200 hectares located on the Pelée mountain, characterized by the exclusiveness of agricultural activities-and the presence of 46 exploitations. Several conclusions can be drawn from this study: historical construction of space at several levels of organization; distribution of logics of space management according to units of constraints; distribution of farming orientations and crop systems depending on distribution of- logics of space management. The environmental consequences have been evaluated by identifying plant health practices, formalized by an indicator of contribution of the plots to the polluting pressure: crops systems and farming orientation appears to be the principal criteria of space differentiation. Multi agents simulations helped to identify the ownership question as being at the basis for setting practices while minimizing spreadings of pesticides. At last, the study shows the need to take into account the various sides of rural development and the new functions of agriculture in order to solve environmental problems

This doctorate was funded by the Regione Emilia Romagna, within a Spinner PhD project coordinated by the University of Parma, and involving the universities of Bologna, Ferrara and Modena. The aim of the project was: - Production of polymorphs, solvates, hydrates and co-crystals of active pharmaceutical ingredients (APIs) and agrochemicals with green chemistry methods; - Optimization of molecular and crystalline forms of APIs and pesticides in relation to activity, bioavailability and patentability. In the last decades, a growing interest in the solid-state properties of drugs in addition to their solution chemistry has blossomed. The achievement of the desired and/or the more stable polymorph during the production process can be a challenge for the industry. The study of crystalline forms could be a valuable step to produce new polymorphs and/or co-crystals with better physical-chemical properties such as solubility, permeability, thermal stability, habit, bulk density, compressibility, friability, hygroscopicity and dissolution rate in order to have potential industrial applications. Selected APIs (active pharmaceutical ingredients) were studied and their relationship between crystal structure and properties investigated, both in the solid state and in solution. Polymorph screening and synthesis of solvates and molecular/ionic co-crystals were performed according to green chemistry principles. Part of this project was developed in collaboration with chemical/pharmaceutical companies such as BASF (Germany) and UCB (Belgium). We focused on on the optimization of conditions and parameters of crystallization processes (additives, concentration, temperature), and on the synthesis and characterization of ionic co-crystals. Moreover, during a four-months research period in the laboratories of Professor Nair Rodriguez-Hormedo (University of Michigan), the stability in aqueous solution at the equilibrium of ionic co-crystals (ICCs) of the API piracetam was investigated, to understand the relationship between their solid-state and solution properties, in view of future design of new crystalline drugs with predefined solid and solution properties.

This doctorate was funded by the Regione Emilia Romagna, within a Spinner PhD project coordinated by the University of Parma, and involving the universities of Bologna, Ferrara and Modena. The aim of the project was: - Production of polymorphs, solvates, hydrates and co-crystals of active pharmaceutical ingredients (APIs) and agrochemicals with green chemistry methods; - Optimization of molecular and crystalline forms of APIs and pesticides in relation to activity, bioavailability and patentability. In the last decades, a growing interest in the solid-state properties of drugs in addition to their solution chemistry has blossomed. The achievement of the desired and/or the more stable polymorph during the production process can be a challenge for the industry. The study of crystalline forms could be a valuable step to produce new polymorphs and/or co-crystals with better physical-chemical properties such as solubility, permeability, thermal stability, habit, bulk density, compressibility, friability, hygroscopicity and dissolution rate in order to have potential industrial applications. Selected APIs (active pharmaceutical ingredients) were studied and their relationship between crystal structure and properties investigated, both in the solid state and in solution. Polymorph screening and synthesis of solvates and molecular/ionic co-crystals were performed according to green chemistry principles. Part of this project was developed in collaboration with chemical/pharmaceutical companies such as BASF (Germany) and UCB (Belgium). We focused on on the optimization of conditions and parameters of crystallization processes (additives, concentration, temperature), and on the synthesis and characterization of ionic co-crystals. Moreover, during a four-months research period in the laboratories of Professor Nair Rodriguez-Hormedo (University of Michigan), the stability in aqueous solution at the equilibrium of ionic co-crystals (ICCs) of the API piracetam was investigated, to understand the relationship between their solid-state and solution properties, in view of future design of new crystalline drugs with predefined solid and solution properties.

L’utilisation de microorganismes ou de substances naturelles d’origine microbienne est une des solutions alternatives actuellement envisagées pour remplacer partiellement ou totalement les pesticides conventionnels. Dans ce contexte, l’objectif de ce travail de thèse a été d’évaluer le potentiel de biocontrôle des souches de P. syringae. Une étude des lipopeptides produits par les souches du complexe P. syringae a d’abord été réalisée car ces molécules sont connues pour leurs activités antimicrobiennes puis l’activité antifongique des bactéries a été analysée. Pour y parvenir, une collection de 709 souches, représentative de la diversité phylogénétique du complexe P. syringae, a été explorée. Grâce à une stratégie faisant intervenir des approches complémentaires de spectrométrie de masse et de bioinformatique, il a été possible de révéler une forte diversité structurale de lipopeptides : 61 lipopeptides dont 38 nouveaux, répartis dans les 5 familles décrites chez P. syringae (syringafactine, syringomycine, corpeptine, syringopeptines 22 et 25) ont été identifiés. Ces lipopeptides sont produits par 81,1% des souches de la collection étudiée, réparties dans 8 des 13 phylogroupes référencés au sein du complexe P. syringae. Concernant leurs activités, 22,3% des souches ont montré une activité antifongique in vitro. Les lipopeptides, produits par 97,3% des souches antifongiques et retrouvés dans des surnageants de culture bruts et semi-purifiés, sont certainement responsables de ces activités. Enfin, deux souches ont montré, in planta, un potentiel intéressant de biocontrôle de la septoriose du blé, causée par le champignon phytopathogène Zymoseptoria tritici. Leurs surnageants de culture bruts et ultrafiltrés, ont montré des niveaux de protection du blé allant jusqu’à 62% par rapport au témoin d’infection
The use of microorganisms or natural substances of microbial origin is one of the identified alternatives to partially or totally replace conventional pesticides. In this context, the aim of this thesis was to evaluate the biocontrol potential of strains belonging to the P. syringae complex. First, the lipopeptides produced by strains of this bacterial complex have been studied because these molecules are known for their antimicrobial activities. Then, the antifungal activity of these bacteria was analysed. To reach this goal, a collection of 709 strains, representative of the phylogenetic diversity of the P. syringae complex, was explored. Through a strategy involving complementary approaches of mass spectrometry and bioinformatics, it has been possible to reveal a huge lipopeptide structural diversity: in total, 61 lipopeptides, including 38 new, distributed into the 5 families described in the P. syringae complex (syringafactin, syringomycin, corpeptin, syringopeptins 22 and 25) have been identified. Lipopeptides producing strains, which represent 81.1% of the collection studied, belong to 8 of the 13 phylogroups referenced in the P. syringae complex. Concerning their activities, 22.3% of the strains have shown an antifungal activity in vitro. Lipopeptides, which are produced by 97,3% of the antifungal strains and are also found in crude and ultra-filtered cell free supernatants, are certainly responsible for these activities. Finally, two strains have shown, in planta, an interesting potential for the biocontrol of Septoria tritici blotch of wheat caused by the fungus Zymoseptoria tritici. Their crude and ultra-filtered cell free supernatants have shown different wheat protection levels up to 62% compared to the infection control

L'objectif de cette these est de faire evoluer le concept de produits phytosanitaires. La demarche entreprise s'articule en deux volets, l'un constitue des trois premiers chapitres et l'autre des deux derniers. Le premier chapitre expose les resultats d'une recherche bibliographique et technique portant sur la protection des parties lignocellulosiques des plantes ligneuses. Le deuxieme chapitre decrit la mise au point, le developpement et l'etude des caracteristiques mecaniques de formulations destinees a la protection antifongique de plaies d'arbre, la couverture des zones de greffe ou encore le piegeage d'insectes se deplacant sur l'ecorce. Les specialites sont soit des pansements acryliques soit des pates a proprietes hydrophobes. Dans le troisieme chapitre, une methode d'extraction et de dosage par ccm/densitometrie des matieres actives formulees dans les pansements de plaies d'arbre est proposee. Celle-ci permet de controler l'evolution du taux des matieres actives au cours du temps, aussi bien dans le produit liquide que dans le film forme apres application. Le deuxieme volet traite de la formulation de produits couvrant les memes domaines que dans le volet precedent mais pour lesquels nous avons cherche a reduire au maximum les problemes de toxicite et de pollution. Nous avons tout d'abord (quatrieme chapitre) selectionne, extrait, fractionne, teste et analyse des extraits vegetaux presentant une activite antifongique ou fourmifuge puis nous avons elabore des emulsions colloidales a partir de composants naturels, alimentaires ou de faible toxicite et pouvant etre employees comme matrice pour les extraits vegetaux (cinquieme chapitre). Des essais de relargage en milieu aqueux et les premiers tests antifongiques in vitro ont ete realises a partir de ces formulations. Ce type de produit peut servir de modele a une nouvelle generation de formulations phytosanitaires, mais aussi pharmaceutiques ou cosmetiques dans lesquelles les matieres actives de synthese seraient substituees ou completees par des extraits d'origine naturelle

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Exposure assessment is an important phase to investigate toxicological risk and it is also relevant for planning surveillance action on farmer s health. This research has the objective of comparing sampling and census methods in order to evaluate chemical exposure. The studies were done in Petrolina PE in São Francisco River Valley in three different work conditions: on weeds, grape and on acerola crops using backpack spraying on August and November, 2010. It is an exploratory and descriptive study. It is also an experimental and quali-quantitative research. The instruments used to measure dermal exposure were: sampling method in which patches are fixed on farmer s outfit and census method in which farmers wear overalls for easy absorption. A questionnaire was applied in order to check the user profile and their functional situation at companies. To data analysis, it was used descriptive statistical parameters and test t - Student to compare sampling averages. The methods evaluated just one operation in activity simulation: hand spraying use. Experiments allowed result comparison among operators, body area, treatment types and farmer safety condition. The main results of activity simulation report that different operational performances happened among users. The biggest amounts were found on weed spraying: inferior limps at 225,4 mg/day (sampling) and 134,1 mg/day (sampling) and chest at 137,2 mg/day (sampling) and 13,5 mg/day (census); grape crops at 271,7 mg/day (sampling) and 136,5 mg/day (census) and chest at 400,3 mg/day (sampling) and 34,2 mg/day (census); acerola crops at 339,8 mg/day (sampling) and 158,7 mg/day (census) and chest at 126,5 (sampling) and 13,32 mg/day (census). The greatest skin exposure happened on grape crops at an average of 1057 mg/day (sampling) and 307,7 mg/day (census) in 7 hours per day. In order to classify safety working conditions, contamination risks were measured by simulated dermal exposure (EDS) and chronicle contamination by safety margin (MS). They were considered safe (MS > 1) treatment on weeds and grape crops in both methods. On acerola treatment, working conditions were classified as unsafe (MS < 1) for Folisuper 600 insecticide at exposure control need of 51, 7% sampling method and safe working condition (MS > 1) using census method. Before the results, we can conclude that there were high discrepancies among exposure assessment in all treatments, as sampling method presented overestimated values superior to 200% and census method showing more reliable and precise results presenting higher efficiency.
A avaliação da exposição é uma etapa importante para a investigação do risco toxicológico e indispensável para o planejamento de ações de vigilância à saúde do trabalhador rural. O presente estudo tem por objetivo comparar os métodos amostral e censitário de atividade para avaliação da exposição a agrotóxicos. Os estudos foram realizados no município de Petrolina PE no Submédio do Vale do rio São Francisco, em três condições de trabalho: em plantas daninhas, cultura da uva e da acerola com uso do pulverizador costal manual, no período de agosto e novembro de 2010. Trata-se de uma pesquisa tipo exploratório e descritivo, de caráter experimental e de abordagem quali-quantitativa. Os instrumentos utilizados para mensurar a exposição dérmica foram: o método amostral, que consiste no uso de coletores absorventes fixados na vestimenta do trabalhador e o método censitário, onde o trabalhador utiliza uma vestimenta de corpo inteiro e fácil absorção. Aplicou-se o questionário para verificar o perfil dos aplicadores e sua situação funcional nas empresas estudadas. Para análise dos dados fez-se uso dos parâmetros estatísticos descritivos e do teste t - Student para comparar as médias das amostras emparelhadas. Os dois métodos avaliaram apenas uma operação na simulação da atividade: as atividades de aplicação manual. Os experimentos permitiram comparar os resultados entre operadores, áreas do corpo, tipos tratamentos e condições de segurança do trabalhador. Os principais resultados da simulação da atividade apontam que: entre os aplicadores ocorreram diferentes performances operacionais em todos os tratamentos. As áreas mais atingidas foram no tratamento de plantas daninhas: os membros inferiores com 225,4 mg/dia (amostral) e 134,1 mg/dia (censitário) e tórax com 137,2 mg/dia (amostral) e 13,5 mg/dia (censitário); uva com 271,7 mg/dia (amostral) e 136,5 mg/dia (censitário) e tórax com 400,3 mg/dia (amostral) e 34,2 mg/dia (censitário); acerola com 339,8 mg/dia (amostral) e 158,7 mg/dia (censitário) e tórax com 126,5 (amostral) e 13,32 mg/dia (censitário). As maiores exposições dérmicas ocorreram no tratamento da cultura da uva que em média foi de 1057 mg/dia (método amostral) e 307,7 mg/dia (método censitário) para uma jornada de trabalhos de 7 horas/dia. Para classificar a segurança das condições de trabalho foram calculados os riscos de intoxicações agudas pela exposição dérmica simulada (EDS) e intoxicação crônica pelo cálculo da margem de segurança (MS). Foram classificadas como seguros (MS > 1) os tratamentos em plantas daninhas e cultura da uva em ambos os métodos. No tratamento da acerola as condições de trabalho foram classificadas como insegura (MS < 1) para o inseticida Folisuper 600 BR com necessidade de controle de exposição de 51,7% com o método amostral e condições de trabalho segura (MS > 1) com o método censitário. Diante dos resultados, concluiu-se que houve elevada discrepância entre as avaliações da exposição em todos os tratamentos, com o método amostral apresentando valores superestimados, com diferenças superiores a 200% e que o método censitário apresentou resultados mais confiáveis e precisos com maior eficiência.

The potato tuber moth, Phthorimaea operculella (Zeller), is a major pest of potato crops worldwide causing significant damage to both field and stored tubers. The current control method in South Africa involves chemical insecticides, however, there is growing concern on the health and environmental risks of their use. The development of novel biopesticide based control methods may offer a potential solution for the future of insecticides. In this study a baculovirus was successfully isolated from a laboratory population of P. operculella. Transmission electron micrographs revealed granulovirus-like particles. DNA was extracted from recovered occlusion bodies and used for the PCR amplification of the lef-8, lef-9, granulin and egt genes. Sequence data was obtained and submitted to BLAST identifying the virus as a South African isolate of Phthorimaea operculella granulovirus (PhopGV-SA). Phylogenetic analysis of the lef-8, lef-9 and granulin amino acid sequences grouped the South African isolate with PhopGV-1346. Comparison of egt sequence data identified PhopGV-SA as a type II egt gene. A phylogenetic analysis of egt amino acid sequences grouped all type II genes, including PhopGV-SA, into a separate clade from types I, III, IV and V. These findings suggest that type II may represent the prototype structure for this gene with the evolution of types I, III and IV a result of large internal deletion events and subsequent divergence. PhopGV-SA was also shown to be genetically more similar to South American isolates (i.e. PhopGV-CHI or PhopGV-INDO) than it is to other African isolates, suggesting that the South African isolate originated from South America. Restriction endonuclease profiles of PhopGV-SA were similar to those of PhopGV-1346 and PhopGV-JLZ9f for the enzymes BamHI, HindIII, NruI and NdeI. A preliminary full genome sequence for PhopGV-SA was determined and compared to PhopGV-136 with some gene variation observed (i.e. odv-e66 and vp91/p95). The biological activity of PhopGV-SA against P. operculella neonate larvae was evaluated with an estimated LC₅₀ of 1.87×10⁸ OBs.ml⁻¹ being determined. This study therefore reports the characterisation of a novel South African PhopGV isolate which could potentially be developed into a biopesticide for the control of P. operculella.

Les mitochondries prises comme révélateurs de l'activité de pesticides ont été extraites de trois types de tissus (cotyledons, feuilles et racines). Les trois types de pesticides utilisés (herbicides 2,4-D et pyrifenops, fongicides aacl ou sels d'alkylammonium) agissent comme découplants-inhibiteurs sur les mitochondries. Les composés du groupe AACL sont les plus puissants et les différences d'action entre mitochondries de tissus chlorophyllien et racinaire semblent provenir de la présence d'une voie de transport d'électrons résistante au cyanure dans les tissus photosynthétiques

A major criticism of the environmental behavior literature is the nearly exclusive focus on the role of attitudes and individual-level characteristics. Despite this concentration on individual-level causes, variation in environmental behavior remains. As individual behavior becomes an increasingly significant source of pollution, a better understanding of the influences individual behavior is critical to addressing environmental degradation. This research re-directs the focus on individual-level influences on environmental behaviors by building models examining the varying dimensions of environmental behaviors as influenced by community characteristics. This is accomplished by testing a series of hypotheses under the auspices of two theoretical frameworks: the neoclassical economic theory and a social contextual model of environmental actions. Using individual-level data from the 1993 and 2000 General Social Survey and MSA data from the U.S. Census and the Environmental Protection Agency, I estimate two-level hierarchical models for three environmentally sensitive behaviors (environmentally sensitive food consumption, environmentally sensitive automobile use, and environmental activism). Multi-level analyses yield models revealing significant associations between MSA measures and individual environmental behaviors. Objective environmental conditions, region of MSA and MSA education level are significantly associated with environmentally sensitive food consumption behaviors, environmentally sensitive automobile use, and environmental activism behaviors, though their influence assumes diverse forms. Among the community measures, MSA education level is the primary social process that produces change in all environmental behaviors. In each of the models, MSA education level exhibits effects on all three behavioral measures and significant cross-level effects on automobile use behaviors. Living in a well educated MSA, particularly in the West or Northeast suggests higher environmental participation. Region of MSA is also a characteristic that must be considered when evaluating environmental behaviors, particularly for those living in the West and Northeast. Theoretical conclusions suggest that individual environmental behavior decision making is not simply a market exchange, but social forces are at work in the individual decision-making process.

L’impact de l’utilisation des agropesticides sur la fonction de reproduction mâle est évalué chez des agriculteurs de Djutitsa (Ouest Cameroun). Le pesticide le plus utilisé par ces agriculteurs est testé in vivo sur la fonction de reproduction du rat mâle, ex vivo et/ou in vitro sur la stéroïdogenèse Leydigienne afin d’évaluer son implication dans les déséquilibres observés chez les agriculteurs. Ensuite, l’effet protecteur des extraits de Carpolobia alba et Basella alba contre les effets délétères dudit pesticide est évalué in vivo chez des rats mâles, ainsi que leur influence sur la production de la protéine de transport des stéroïdes (SHBG) par les cellules HepG2. Les résultats montrent que les agriculteurs utilisent 25 agropesticides et présentent des symptômes liés à une protection inadéquate. De plus, ils présentent une diminution de la testostérone avec une élévation de l’androstènedione sériques comparé au groupe témoin non exposé (P < 0,05) et ces déséquilibres androgéniques sont accompagnés de difficultés de reproduction. Le manèbe est l’agropesticide le plus utilisé et perturbe chez le rat mâle la stéroïdogenèse Leydigienne (à travers l’inhibition de la CYP11A1) et la fertilité. Cette fertilité est améliorée/rétablie lorsque le pesticide est concomitamment administré avec l’un des extraits, suggérant ainsi l’effet protecteur desdits extraits qui est imputable à leur activité androgénique également démontré chez les rats. Toutefois, ces extraits et le manèbe n’affectent pas la production de la SHBG in vitro. Ces résultats soulignent l’altération de la fonction de reproduction mâle par les agropesticides et l’effet bénéfique des plantes médicinales
The effect of agropesticides use on male reproductive function was evaluated in male farmers in Djutitsa (West Cameroon). The most frequently used agropesticide by farmers was selected and tested in vivo on the reproductive function of male rats, ex vivo and/or in vitro on Leydig cells steroidogenesis, in order to evaluate its implication in disorders observed in farmers. The ability of 2 Cameroonian medicinal plants (Carpolobia alba and Basella alba) to prevent pesticide-induced toxicity was also investigated in vivo in male rats. Furthermore, both extracts and selected pesticide were tested on the release of a steroid transporter protein (SHBG) by HepG2 cells. The results showed that farmers used 25 agropesticides and presented symptoms related to inadequate protection. Moreover, they had lower serum testosterone and higher androstenedione levels compared to a control group with no history of agropesticide exposure (P < 0.05), and these androgenic imbalances were accompanied by difficulties of reproduction. Maneb was the most common ingredient, and its administration to male rats resulted in decrease/alteration of Leydig cells steroidogenesis (through inhibition of CYP11A1) as well as fertility. The latter fertility was improved/restored when maneb was coadministrated to rats with any of the plant extracts, suggesting their protective effect that may be attributed to their proven androgenic activity. However maneb and the plant extracts did not affect SHBG release by HepG2 cells. These results highlight agropesticides deleterious effect on male reproductive function, which may be prevented by the investigated plant extracts

La mesure de la cinetique de fluorescence de la chlorophylle, est un bon moyen d'evaluer la reponse provoquee, dans les feuilles entieres, par des inhibiteurs de la reaction de hill. En determinant, apres un contact racinaire, dans les differentes parties de jeunes plants d'orge vulgaire (racines, tiges et fractions de la feuille principale), les concentrations des produits testes et de leurs residus de degradation, l'absorption, le transfert, la metabolisation et l'efficacite inhibitrice sont etudies. Le facteur de concentration racinaire, rcf, et le facteur de concentration dans le fux de transpiration, tscf, sont directement correles a la lipophilicite (log p) du neburon et du diuron. Il existe un log p optimal pour le transfert vers les parties aeriennes. La concentration necessaire pour provoquer une reponse donnee, est beaucoup plus elevee dans la feuille que celle determinee, in vitro, sur des chloroplastes isoles. Cela est vrai pour les deux produits qui ont la meme efficacite bien que leur cinetique de transfert soit differente

Cette thèse porte sur la régulation des innovations en Europe. Elle examine en particulier l'impact économique des procédures d'Autorisation de Mise sur le Marché (AMM) sur les comportements des acteurs économiques à savoir les firmes innovantes. Il s'agit d'un travail appliqué au secteur de la santé des plantes dans lequel l'AMM joue un rôle central. En effet, dans ce secteur, la mise sur le marché des pesticides est subordonnée à une autorisation officielle. Les procédures d'autorisation de mise sur le marché (AMM) des nouveaux produits consistent à vérifier qu'ils n'ont pas d'effets toxiques inacceptables sur la santé et l'environnement et à définir des conditions d'utilisation dans lesquelles ces produits sont réputés efficaces. En Europe, ces procédures sont instruites par des autorités européennes ou nationales. Dans le cas des pesticides, les matières actives sont autorisées à l'échelle européenne, les spécialités commerciales le sont à l'échelle nationale, par reconnaissance mutuelle au sein d'une zone géographique. Au cours des dernières décennies, les exigences dans le domaine des risques sanitaires ont conduit à un renforcement des contraintes imposées pour la mise en marché des produits phytosanitaires. Ces exigences renforcées ont conduit à une réduction du nombre de molécules autorisées en rapport au nombre de molécules potentiellement efficaces. Par exemple, le nombre de molécules pesticides autorisées a été réduit de moitié (de 800 à 400) au cours des dix dernières années. C'est pourquoi, l'objet principal de cette recherche est d'étudier les effets des procédures d'AMM sur le comportement des firmes agrochimiques. Cette recherche s'articule autour de trois chapitres. Le premier chapitre est théorique. Il analyse les interactions stratégiques entre les agences de régulation des pesticides dans un contexte d'autorisation de mise sur le marché par reconnaissance mutuelle. Le chapitre 2 est à la fois théorique et empirique et porte sur les délais de mise sur le marché des substances actives phytosanitaires. Dans le chapitre 3, nous examinons, à l'aide d'un modèle théorique, l'impact de la régulation des pesticides sur les incitations des firmes agrochimiques à investir en R&D
This thesis focuses on the regulation of innovations in Europe. In particular, it analyses the economic impact of the market approval procedures on the behavior of economic actors such as innovative firms. This is an applied work in the health sector of plants in which the market approval procedures play a central role. Indeed, in this area, the introduction on the market of pesticides is subject to an official approval. The market approval procedures for new products are to ensure that they do not have unacceptable toxic effects on human health and the environment and to define the conditions of use in which these products were efficient. In Europe, these procedures are investigated by European or national authorities. In the case of pesticides, the active substances are approved at EU level and the pesticides formulation at the national level through mutual recognition within a geographic area. In recent decades, the requirements in the field of health risks have led to a strengthening of the constraints imposed on the approval of pesticides. These stringent requirements have led to a reduction in the number of approved molecules relative to the number of molecules potentially efficient. For example, the number of approved actives substances was reduced by half (800 to 400) over the last ten years. Therefore, the main purpose of this research is to study the effects of market approval procedures on the behavior of agrochemical companies. This research is based on three chapters. The first chapter is theoretical. It analyses the strategic interactions between pesticide regulatory agencies in the context of market approval through the mutual recognition system. The chapter 2 is both a theoretical and an empirical work. It examines the examination delays of plant protection active substances. In Chapter 3, we examine, using a theoretical model, the impact of the regulation of pesticides on the incentives of agrochemical companies to invest in R & D

Le travail presente dans ce memoire concerne une etude du devenir d'un herbicide du mais, l'atrazine en condition de plein-champ: bilan et modes de dissipation. Des experimentations de laboratoire mettant en jeu des methodes diverses (suivi de l'atrazine #1#4c, couches minces et colonnes de terre, lysimetre non remanie) permettent d'etayer les resultats obtenus sur la parcelle experimentale du site observatoire des pollutions diffuses du lycee agricole de la cote saint andre (isere, france) ou a ete suivie pendant 3 ans la composition en herbicide et metabolites du sol sur 1 metre de profondeur et celle de l'eau interstitielle prelevee par bougies filtrantes. La matiere active (1 kg/ha) apportee annuellement fin avril se dissipe selon cinq voies d'importances tres inegales: volatilisation (15%), absorption par la culture (10%), adsorption sur le complexe argilo-humique et metabolisation (40-50%), entrainement vers les eaux profondes (30-40%). Dans la situation etudiee, les deux voies principales sont la metabolisation par la microflore du sol et l'entrainement lors des episodes pluvieux precoces. Apres un an de culture, la teneur en atrazine et derives au sein du premier metre de sol est voisine de 400 g/ha ce qui indique que l'evacuation de la matiere active n'est pas complete. Notre etude de terrain completee par une experimentation de laboratoire, conduit a mettre en evidence la possibilite de pertes precoces importantes de matiere active durant les deux premiers mois de culture. Trois concepts importants relatifs a l'efficacite d'un herbicide de prelevee emergent de notre etude: la concentration critique dans l'eau du sol, la duree critique durant laquelle cette concentration doit etre maintenue pour assurer l'effet herbicide, la profondeur critique qui represente la couche de sol dans laquelle doit jouer l'effet herbicide. Pour l'atrazine en culture de mais, dans nos conditions, ces criteres ont ete mesures: concentration critique: entre 50 et 200 micromoles ; duree critique: deux mois ; profondeur critique: 10 cm. Avec 1 kg/ha d'atrazine sous forme de suspension concentree, les trois criteres d'efficacite sont remplis malgre d'importantes pertes par drainage lors des episodes pluvieux precoces. Des modifications de formulation ayant pour consequence un relargage progressif devrait permettre l'economie d'une part importante de matiere active. La derniere partie de ce travail concerne une approche de mise en place de solutions alternatives de traitements herbicides en culture de mais

Dissertação de Mestrado em Biodiversidade e Biotecnologia Vegetal apresentada à Faculdade de Ciências e Tecnologia
Pesticidas designam-se como substância químicas, ou um agente biológicos intencionalmente libertados no meio ambiente, que sejam capaz de reduzir, prevenir ou controlar populações de pragas prejudiciais, como animais, ervas daninhas, fungos, bactérias ou vírus. Estas pragas são definidas como organismos potencialmente perigosos ou prejudiciais à nossa alimentação ou saúde, sendo responsáveis por despesas anuais de biliões de dólares devido à produção de produtos químicos sintéticos dispendiosos.A necessidade de novas soluções biologicamente sustentáveis ao uso de pesticidas levou a um recente crescimento no interesse à investigação e produção de biopesticidas à base de plantas e os compostos por elas produzidos. No presente estudo foram realizados e fracionados à base de solventes orgânicos frações vegetais de folhas das espécies Solanum betaceum Cav. e Corema album (L.) D. Don, e a atividade antioomicética dos mesmos foi testada in vitro no crescimento de Phytophthora cinnamomi Rands. O extrato inicial do material foliar foi preparado com etanol e o fracionamento do mesmo foi realizado com n-hexano, clorofórmio, acetato de etilo e butanol, por esta ordem, através de um sistema de separação bifásica. P. cinnamomi demonstra sensibilidade à fração butanólica de S. betaceum e a todas as frações de C. album, particularmente ao extrato inicial etanólico. A fração butanólica de S. betaceum demonstra ser rica em polifenóis, polissacarídeos e ésteres. As várias frações de C. album possuem pectinas, ésteres, triterpenóides e compostos aromáticos como fenóis.
Pesticides are chemical substances, or a biological agents intentionally released into the environment, capable of deterring, preventing or controlling populations of harmful pests such as animals, weeds, fungi, bacteria or viruses. These pests are defined as organisms that can be hazardous to our food and health, and are liable for yearly expenses of billions of dollars through the production of costly synthetic chemicals. The urge for new environmentally friendly solutions to the pesticides has led to a recent increasing interest in the research and production of plant-based biopesticides and the compounds they produce. In the present study, leaves of the species Solanum betaceum Cav. and Corema album (L.) D. Don were used to create crude ethanol extracts which were subsequently fractioned using organic solvents. The species leaf fractions were tested in vitro for their anti-oomycete activity on the growth of Phytophthora cinnamomi Rands. The initial extract of the leaf material was prepared with ethanol and the fractionation was carried out with n-hexane, chloroform, ethyl acetate and butanol, in that order, through a biphasic separation system. P. cinnamomi shows sensitivity to the butanolic fraction of S. betaceum and to all fractions of C. album, particularly to the initial C. album ethanolic extract. The butanolic fraction of S. betaceum proves to be rich in polyphenols, polysaccharides and esters. The various fractions of C. album contain pectins, esters, triterpenoids and aromatic compounds such as phenols.
Universidade de Coimbra - Projeto “RENATURE- Valorização dos Recursos Naturais Endógenos da Região do Centro” (CENTRO-01-0145-FEDER-000007). Fundado pela Comissão de Coordenação da Região Centro (CCDR-C) e subsidiado pelo Fundo Europeu de Desenvolvimento Regional (FEDER). Projeto PTDC/BAA-AGR/32265/2017: “Tamarillo breeding: better plants for better products”. (projeto nº 032265 no âmbito do Aviso de concurso nº 02/SAICT/2017). Projeto Ideas4life Novel Maritime Plant Food Ingredients (C493053224-00089325); Horizon 2020 Framework Programme.

博士
國立臺灣大學
農業化學系
85
Physical and chemical properties of chemical compounds as well as their bioactivities alter due to the changes in their chemical structures. Therefore, the quantitative structure parameters can be used to describe the physical and chemical properties of different compounds and their bioactivities.In the present study, hydrogen bond acidity index (HAI), hydrogen bond basicity index (HBI), molecular weight (MW) and molecular connectivity indices are selected as quantitative structure parameters. The capacity factors (k'') of 19 carbamate pesticides are determined on the reversed-phase column with mobile phases of methanol/water or acetonitrile/water in various ratios. By the use of multiple regression analysis, the ln k'' values are screened against the quantitative structure parameters for all possible two-, three- and four-variable combinations. With different mobile phase systems, the best relationships are obtained to the 4-variable, the multiple correlation coefficients are between 0.898-0.934. The independent variable HBI in all regression equations means that HBI is an effective parameter in retention of carbamate pesticides in reversed-phase high-performance liquid chromatographic(RP-HPLC).The inhibition of acetylcholinesterase by carbamate pesticides can be explained with affinity constant (Ka) and carbamylation constant (kc), in the other word, in explanation of inhibition constant (Ki). The natural logarithm value of these three constants can be described by the quantitative structure parameters. The best relationships are obtained to the 4-variable, the multiple correlation coefficients are between 0.911-0.946. Through the further study, (1／0XN)2 and (R1 3XcV) are effective parameters to explain the inhibition of carbamate pesticides on acetylcholinesterase. The natural logarithm values of median lethal concentration (LC50) of carbamate pesticides to Daphnia pulex can also be described by the quantitative structure parameters, the best relationship is obtained to the 4-variable, the multiple correlation coefficient is 0.888.The above mentioned regression equations are tested by random effect and F-test. The regression coefficients are also tested by t-test. All of the statistic results are significant. The values of these quantitative structure parameters are sure to reveal certain relationship among ln k'', ln Ka, ln Ki, ln kc and ln (LC50).

Spiders are naturally occurring predators of insects in agroecosystems. The use of broad spectrum pesticides in agriculture is likely to disrupted spider communities and have a negative impact on their role as biocontrollers. The overall abundance, the species richness, diversity and guild structure of spiders in tropical mango orchards in central Queensland were investigated in this study. Experiments were performed to assess the potential of spiders as natural predators to pest insects in mango orchards. The effects of pesticides on the spider communities were assessed to establish the extent to which the communities were disrupted and the extent of recovery from this type of disturbance. The short term (acute) and long term (chronic) effects were investigated. The spiders in unsprayed mango orchards were relatively high in abundance, species richness and species diversity. Spiders were present in significant numbers at all sampling times,both day and at night, and during all seasons. The results suggest that spiders do not capture large numbers of prey. However spider exhibit a diversity of capturing techniques so that they capture a variety of insects. The most common guild was the orb-weavers. The spider abundance and diversity four days after spraying with methidathion suggested that recovery of spider after disruption such as the use of pesticides' occurs quickly. Presumably this recovery occurs due to spiders moving into the orchard from surrounding bush land. The long term use of pesticide does appear to disrupt the community and as evidenced by decreases in the abundance, species richness and diversity of spiders. While it is unlikely that pesticide usage will be eliminated in most commercial mango orchards, this study demonstrates that spiders are potentially important biocontrollers and that they are adversely affected by pesticide use. In the longer term, it will be desirable to develop IPM strategies to minimise pesticide use and maximise the role of spiders as biocontrollers. Such strategies will depend on studies such as this one and extensions of it.

This study identified new compounds with pest control activities. The two sources of candidates that were followed here were the main heartwood extract of Alaska Yellow Cedar (AYC) constituents and several semi-synthetic counterparts. Five compounds were isolated and identified for the first time in AYC heartwood in this research: two monoterpenes, two sesquiterpenes, and one lignan. The two monoterpenes were (1S)-2-oxo-3-p-menthenol (41) and (4R)-4-hydroxy-4-isopropyl-cyclohex-1-enecarboxylic acid (63). The two sesquiterpenes were (5S,7R,10R,11R)-eudesm-4(14)-ene-11,12-diol (46) and (4R,5S,7R)-1(10)- eremohpilen-11,12-diol (59). The lignan was (1R,2S,5R,6S)-2,6-bis-(3,5- dimethoxy-4-hydroxyphenyl)-3,7-dioxabicyclo-[3.3.0]octane,(67). Structures for these compounds were confirmed on the basis of spectroscopic techniques such as 1- and 2-D NMR, high resolution MS and IR. The pest control activity studies of 15 compounds isolated or semi-synthesized from AYC heartwood were conducted at the Centers for Disease Control and Prevention (CDC). Two types of studies were conducted--short-term (24h) and residual (over 1-4 weeks) activity for application against three types of pests related to human health - nymphal I. scapularis ticks, adult X cheopis fleas and adult Ae. eagypti mosquitoes. The 24 h studies revealed that nootkatone, valencene-13-aldehyde and valencene-13-ol were the most active among the studied compounds against the three pests. They exhibited highly improved pest control activities compared to valencene. This suggests that oxidation on both positions C-2 and C-13 of the eremophilane ring structure has an important effect on the activity. For compounds where the conformation of the eremophilane bicyclic ring has been altered, the activity seemed to diminish greatly. The above mentioned three compounds can be good candidates as pest control lead compounds. The residual studies revealed that the most active compounds exhibited activity profiles that generally decreased with time. Although the long-term safety of these compounds has yet to be evaluated, the natural origin and the long history of use of these compounds suggest that they can be promising candidates. This study revealed that the three most promising compounds in the 24 h study exhibited reasonably promising behavior, which makes them even stronger as pest control candidates.
Graduation date: 2004

碩士
國立交通大學
環境工程系所
102
This study present the toxicity data of ten organothiophosphorus compounds to Daphnia magna using 48-hours acute toxicity test. Results indicate that Phoxim is the most toxic compound, the reason caused higher toxicity of Phoxim is dependent on its higher charge density due to benzyl cyanide group. Quantitative structure-activity relationships (QSARs) were established between the EC50 values and various molecular descriptors, and a highly predictive two-variable QSAR models were obtained. According to QSAR models, the toxic mechanism was highly related to hydrophobicity of these compounds, and this result indicated that organothiophosphorus compounds caused toxicity to Daphnia magna mainly due to permeate through membrances, changing the components of the cell membrances. Adding reactive parameters slightly improve the r2 values indicated that the reaction rate of the organothiophosphate with AChE, the conversion of organothiophosphate to organophosphate and the molecule polarity are not rate-limiting steps. The preliminary environmental risk assessment was conducted following the European Union RQ model. Results point out that most of these compounds exist potential risks to aquatic environment. Risk quotient derived from acute and estimated chronic toxicity data were different, using acute toxicity data may overestimate the risk quotient value.