No description available.

A field study was designed to determine if foliar boron (B) sprays could increase fruit set and yield of 'Parent Washington' navel oranges (Citrus sinensis). Treatments consisted of two application timings (prebloom and postbloom) and five application rates 0, 250, 500, 750 and 1000 ppm B as Solubor. Leaf B levels had a significant response to both application timing and rate. There were no significant difference in fruit quality or yield.

Revised / 3 pp.

No description available.

The incidence, influencing factors and mechanisms of resistance to insecticides from a range of chemical groups were examined in UK and European populations of the glasshouse whitefly, Trialeurodes vaporariorum (Westwood). Toxicological assessments of populations from a range of plant production glasshouses and comparisons with the responses of a laboratory susceptible strain disclosed levels of resistance to pyrethroid, organophosphate, insect growth regulator (IGR) and neonicotinoid insecticides. Responses to conventional compounds indicated varying levels of resistance, potentially reflecting disparate usage between collection sites. All strains examined possessed resistance to the IGR, buprofezin; some populations were virtually immune to this commonly used control agent. Selection experiments demonstrated reciprocal crossresistance between buprofezin and a further IGR, teflubenzuron, both of which are frequently incorporated into integrated pest management (IPM) programmes for this species. Results for the leading neonicotinoid, imidacloprid, revealed resistance in both UK and European strains, representing the first documented cases of neonicotinoid resistance in this species worldwide, and the first in any insect species within the UK. The lethal effects of vapour emitted by applications of buprofezin and the anti-feedant effects of imidacloprid were demonstrated in T. vaporariorum for the first time. The potential consequences of these factors for both the control and selection of resistance were highlighted. Mechanistic studies using electrophoresis and kinetic spectrophotometer readings showed that neither non-specific esterases nor modified acetylcholinesterases were involved with resistance to either pyrethroid or specific organophosphate insecticides.

Background: The whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is among the 100 worst invasive species in the world. As one of the most important crop pests and virus vectors, B. tabaci causes substantial crop losses and poses a serious threat to global food security. Results: We report the 615-Mb high-quality genome sequence of B. tabaci Middle East-Asia Minor 1 (MEAM1), the first genome sequence in the Aleyrodidae family, which contains 15,664 protein-coding genes. The B. tabaci genome is highly divergent from other sequenced hemipteran genomes, sharing no detectable synteny. A number of known detoxification gene families, including cytochrome P450s and UDP-glucuronosyltransferases, are significantly expanded in B. tabaci. Other expanded gene families, including cathepsins, large clusters of tandemly duplicated B. tabaci-specific genes, and phosphatidylethanolamine-binding proteins (PEBPs), were found to be associated with virus acquisition and transmission and/or insecticide resistance, likely contributing to the global invasiveness and efficient virus transmission capacity of B. tabaci. The presence of 142 horizontally transferred genes from bacteria or fungi in the B. tabaci genome, including genes encoding hopanoid/sterol synthesis and xenobiotic detoxification enzymes that are not present in other insects, offers novel insights into the unique biological adaptations of this insect such as polyphagy and insecticide resistance. Interestingly, two adjacent bacterial pantothenate biosynthesis genes, panB and panC, have been co-transferred into B. tabaci and fused into a single gene that has acquired introns during its evolution. Conclusions: The B. tabaci genome contains numerous genetic novelties, including expansions in gene families associated with insecticide resistance, detoxification and virus transmission, as well as numerous horizontally transferred genes from bacteria and fungi. We believe these novelties likely have shaped B. tabaci as a highly invasive polyphagous crop pest and efficient vector of plant viruses. The genome serves as a reference for resolving the B. tabaci cryptic species complex, understanding fundamental biological novelties, and providing valuable genetic information to assist the development of novel strategies for controlling whiteflies and the viruses they transmit.

As dificuldades técnicas atuais para o manejo e controle de pragas que atacam as lavouras em nosso país, vêm incentivando a busca por métodos de controle alternativos e/ou complementares aos convencionais, destacando-se o potencial dos inseticidas botânicos. O Neem é uma planta nativa da Índia pertencente à família Meliaceae, conhecida popularmente como Nim ou Neem e tem sido usada por séculos no Oriente como: planta medicinal no tratamento de inflamações, infecções virais, hipertensão e febre, planta sombreadora, repelente, material para construção, combustível, lubrificante, adubo e mais recentemente como praguicida natural. Mesmo alavancada pela produção orgânica de alimentos, o uso de bioinseticidas ainda carece de mais pesquisas acerca de cada formulação principalmente sua ação sobre os organismos, sendo assim esta pesquisa visou avaliar os efeitos do extrato aquoso das folhas de Neem (Azadiractha indica) em ratos Wistar machos em idade reprodutiva, objetivando avaliar quais possíveis danos induzidos a exposição por oito dias ao extrato da planta pode resultar e também avaliar sua capacidade contraceptiva trazendo respostas importantes afim de se conhecer esta importante alternativa ao uso de agrotóxicos sintéticos. Para este estudo foram utilizados 20 ratos Wistar que foram divididos em 4 grupos compostos por 5 animais cada, sendo: G1 - 10.000ppm, G2 - 7.500ppm, G3 - 5.000 ppm e G4 - controle com água destilada. O volume administrado foi padronizado em 1 ml para cada animal e a administração deu-se por gavagem, por oito dias. Para se estudar as reações ocasionadas pelo tratamento realizamos nos animais após a administração das diferentes doses do composto o reconhecimento de sinais clínicos de toxicidade, a investigação das alterações fisiológicas, análise da qualidade do sêmen e avaliação macro e microscópicas dos órgãos alvo fígado, rins e testículos. Nossos resultados apontam que o extrato aquoso de Neem administrado por oito dias, via oral, nas doses empregadas apresentou baixa toxicidade, uma vez que não foi revelada nenhuma alteração nos quesitos avaliados, contudo apresentou resultados que levam a considerar sua capacidade contraceptiva, por terem alterando de forma negativa a motilidade e viabilidade espermática nas maiores doses administradas. / The current technical difficulties for the management and control of pests that attack the crops in our country have been encouraging the search for alternative and / or complementary control methods to conventional ones, highlighting the potential of the botanical insecticides. Neem is a plant native to India belonging to the family Meliaceae, popularly known as Nim or Neem and has been used for centuries in the East as: medicinal plant (in the treatment of inflammation, viral infections, hypertension and fever), shading plant, repellent, building material, fuel, lubricant, fertilizer and more recently as natural pesticide. Even though the use of bio-insecticides is still underpinned by organic food production, there is still a need for more research on each formulation, especially its action on organisms. This research aimed to evaluate the effects of the aqueous extract of Neem leaves (Azadiractha indica) on Wistar rats males of reproductive age, aiming to evaluate which possible induced damages the exposure for eight days to the extract of the plant can result and also to evaluate its contraceptive capacity bringing important answers in order to know this important alternative to the use of synthetic agrochemicals. For this study 20 Wistar rats were divided into 4 groups composed of 5 animals each, being: G1 - 10.000ppm, G2 - 7,500ppm, G3 - 5,000 ppm and G4 - control with distilled water. The volume administered was standardized in 1 ml for each animal and administration was given by gavage for eight days. In order to study the reactions caused by the treatment, the clinical signs of toxicity were confirmed in the animals after administration of the different doses of the compound, investigation of physiological changes after administration of the extract, analysis of the semen quality and macro and microscopic evaluation of the organs target liver, kidneys and testicles. After analysis of the results obtained it can be considered that the aqueous extract of Neem administered for eight days, orally, in the doses used presented low toxicity, since no changes were revealed in the evaluated items, however presented results that lead to consider its contraceptive capacity, because it has negatively altered motility and sperm viability at the highest doses administered.

Os insetos são o grupo de organismos multicelulares mais abundantes e diversos, habitando os mais variados ambientes. Muitas de suas adaptações a condições adversas podem estar relacionadas à sua associação a bactérias. O conhecimento da diversidade dessa associação pode elucidar a importância desses microrganismos nas respostas de insetos a fatores bióticos e abióticos. Bactérias também são o principal alvo de exploração para o desenvolvimento de produtos de interesse biotecnológico. Dada à sua diversidade e interações com o ambiente, insetos representam um novo nicho para a exploração de microrganismos com potencial biotecnológico. A longa história de associação dos insetos com bactérias e os dados recentes da participação da microbiota a eles associada na degradação de moléculas orgânicas, naturais e/ou sintéticas, indicam o potencial desses microrganismos de interferir na resposta do inseto a inseticidas. Adicionalmente, simbiontes bacterianos associados aos insetos também podem ser uma fonte promissora de compostos bioativos. A descoberta de novos compostos naturais vem decaindo, surgindo a necessidade de exploração de novos nichos de microrganismos e o uso de novas tecnologias para superar o número reduzido de novas moléculas identificadas. Assim, este trabalho buscou explorar simbiontes de insetos para o estudo da sua participação na metabolização de xenobióticos pelo hospedeiro e a identificação de novos compostos inseticidas, tendo como objetivos investigar i) os mecanismos envolvidos na degradação de inseticidas e sua contribuição na capacidade de sobrevivência do hospedeiro, e ii) a diversidade biológica na busca de novas moléculas inseticidas. Bactérias com potencial de degradação de xenobióticos isoladas da microbiota intestinal de insetos resistentes a inseticidas foram utilizadas para a colonização do trato intestinal de Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) suscetível à inseticidas e investigação da sua participação na sobrevivência do hospedeiro quando exposto a inseticidas, assim como a existência de custo adaptativo da associação a bactérias com capacidade de metabolização de inseticidas. O isolado IIL-Cl29 Leclercia adecarboxylata foi capaz de contribuir para a sobrevivência de lagartas expostas a chlorpyrifos ethyl, passando a exigir uma CL50 cerca de 2 vezes superior àquela de lagartas apossimbiontes. Estudo de biologia comparada entre a linhagem apossimbionte e aquela associadas ao isolado IIL-Cl29 demonstrou a existência de custo adaptativo para essa associação, quando na ausência da pressão de seleção do inseticida. A investigação dos mecanismos envolvidos na metabolização de inseticidas por bactérias simbiontes de S. frugiperda resistente ao organofosforado chlorpirifos ethyl, aos piretroides lambda-cyhalothrin e deltamethrin, a espinosina spinosad e a benzoilureia lufenuron revelou, por meio de análises químicas, que essas bactérias são capazes de metabolizar e bioacumular inseticidas interferindo ativamente na atividade de xenobióticos no hospedeiro. O isolado IIL-Luf14 Microbacterium arborescens foi selecionado para a realização de estudos mais aprofundados para a identificação de produtos de degradação e comprovação do mecanismo de bioacumulação de lufenuron. O potencial de simbiontes de insetos para o isolamento de bioinseticidas foi avaliado em estudos da diversidade de bactérias cultiváveis associadas a Acromyrmex coronatus (Fabricius, 1804) (Hymenoptera: Formicidae). Foram identificados 46 isolados pertencentes a Actinobacteria, Firmicutes e Proteobacteria associados a essa formiga e estudos da atividade inseticida in vivo e in vitro de extratos orgânicos de metabólitos mostraram grande variação nos resultados de atividade. Ensaios in vivo com lagartas de 1º instar de S. frugiperda mostraram-se mais adequados, e o isolado Asp77 Streptomyces drozdowiczii foi selecionado para a identificação de moléculas ativas com efeito inseticida. Dois compostos bioativos com atividade inseticida foram identificados e a atividade inseticida atribuída para duas classes químicas diferentes: um composto pirrolobenzodiazepino e um alcaloide. Nossos resultados comprovam a hipótese de que simbiontes participam da metabolização de xenobióticos em insetos, ao mesmo tempo que possuem potencial para exploração de novos compostos inseticidas. / The insects are the most diverse and abundant group of multicellular organisms, inhabiting a range of environments. Many of their adaptations to restricting conditions are related to their association with bacteria. The knowledge of the diversity of insect associations with bacteria can elucidate their role in insect response to biotic and abiotic factors. Bacteria are also the main target of exploitation for the development of biotechnological products. Insect´s diversity and interactions with the environment turn insects a new niche for the exploration of microorganisms with biotechnological potential. The long history of association of insects with bacteria and the participation of insect-associated bacteria in the degradation of natural and/or synthetic organic molecules indicate the potential of these microorganisms to interfere with insect response to insecticides. Additionally, bacterial symbionts associated with insects may also be a promising source of bioactive compounds. The discovery of new natural compounds has been declining, requiring the exploration of new niches of microorganisms and the use of new technologies to overcome the reduced number of molecules discovered. This work aimed to investigate the role of insect-associated bacteria in the metabolism of xenobiotics in the host and their potential to synthesize insecticidal compounds. Our objectives were to demonstrate i) the mechanisms involved in insecticide degradation by selected microbial symbionts, and to determine their contribution to host survival when exposed to insecticides, and ii) the biological and metabolic diversity of the microbiota associated with a leaf cutting ant. Bacteria that are able to degrade xenobiotics isolated from the gut microbiota of insecticide-resistant insects were used for the colonization of the gut of a susceptible strain of Spodoptera frugiperda (JE Smith, 1797) (Lepidoptera: Noctuidae). Comparisons of larval survival after insecticide exposure and the existence of adaptive costs of the association were done by using a aposymbiotic and infected susceptible lines. Suceptible larvae infected with IIL-Cl29 Leclercia adecarboxylata require twice the dose of chlorpyrifos ethyl to kill 50% of the larave (LC50) when compared to the aposymbiotic larvae. But the association with IIL-Cl29 was shown costly to S. frugiperda, particularly affecting female fecundity. However, no fitness costs were detected to infected larvae in the presence of the selection pressure (insecticide). GC-MS and LC-MS-MS analyses of the bacteria isolated from resistant larvae of S. frugiperda to organophosphate (chlorpirifos ethyl), pyrethroid (lambda-cyhalothrin and deltamethrin), spinosyn (spinosad) and benzoylurea (lufenuron) revealed they are able to hydrolyze, metabolyze and bioaccumulate insecticides, showing they can actively interfere with the efficacy of insecticides against the host. These processes were better characterized for the isolate IIL-Luf14 Microbacterium arborescens. The species and metabolic diversity of culturable bacteria associated with Acromyrmex coronatus (Fabricius, 1804) (Hymenoptera: Formicidae) were investigated to demonstrated their potential to produce bioinsecticides. A total of 46 isolates belonging to Actinobacteria, Firmicutes and Proteobacteria were identified. In vivo and in vitro assays to detect insecticide activity in organic extracts of fermentates indicated a great number of active extracts. In vivo assays with 1st instars of S. frugiperda were more adequate in detecting toxic molecules to insects, and the isolate Asp77 Streptomyces drozdowiczii was selected for the identification of active molecules with insecticidal effect. Two bioactive compounds with insecticidal activity were identified and the insecticidal activity attributed to two different chemical classes: pyrrolobenzodiazepine and alkaloid. Our results support the hypothesis that symbionts participate in the metabolization of xenobiotics in insects, at the same time that they have potential for exploration of new insecticides.

Chan Kam Che. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 199-219). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstracts --- p.iii / 摘要 --- p.v / Contents --- p.vii / List of figures --- p.xiv / List of tables --- p.xix / Abbreviations --- p.xxii / Chapter Chapter I --- Introduction --- p.1 / Chapter 1.1 --- Persistent organic pollutants --- p.1 / Chapter 1.2 --- DDT and DDE --- p.2 / Chapter 1.2.1 --- Background --- p.2 / Chapter 1.2.2 --- Health effects --- p.4 / Chapter 1.2.3 --- Environmental exposure of DDE --- p.4 / Chapter 1.2.4 --- Level of DDE in human --- p.9 / Chapter 1.2.5 --- Biodegradation of DDE --- p.10 / Chapter 1.3 --- Remediation methods --- p.11 / Chapter 1.3.1 --- Physical/ chemical treatment --- p.11 / Chapter 1.3.2 --- Bioremediation --- p.13 / Chapter 1.4 --- Fungal Bioremediation --- p.14 / Chapter 1.5 --- Ligninolytic enzymes --- p.15 / Chapter 1.5.1 --- Laccase --- p.15 / Chapter 1.5.2 --- Peroxidases --- p.20 / Chapter 1.5.2.1 --- Manganese Peroxidase (MnP) --- p.20 / Chapter 1.5.2.1 --- Lignin Peroxidase (LiP) --- p.24 / Chapter 1.6 --- Cultivation of Pleurotus pulmonarius --- p.27 / Chapter 1.7 --- Enzyme technology on environmental cleanup and its limitation --- p.28 / Chapter 1.8 --- Aims and objectives of this study --- p.29 / Chapter Chapter II --- Materials and Methods --- p.30 / Chapter 2.1 --- Organism and growth conditions --- p.30 / Chapter 2.2 --- Cultivation and the expression of the ligninolytic enzyme-coding genes during solid-state-fermentation of edible mushroom Pleurotus pulmonarius --- p.30 / Chapter 2.3 --- Treatment of DDE by living P. pulmonarius --- p.31 / Chapter 2.3.1 --- Optimization of DDE removal in broth system --- p.31 / Chapter 2.3.1.1 --- Effects of initial DDE concentration on the removal of DDE --- p.32 / Chapter 2.3.1.2 --- Effects of inoculum size on the removal of DDE --- p.33 / Chapter 2.3.1.3 --- Effects of incubation time on the removal of DDE and transcriptional profiles of the ligninolytic enzyme-coding genes --- p.33 / Chapter 2.3.2 --- Optimization of DDE removal in soil system --- p.34 / Chapter 2.3.2.1 --- Effects of initial DDE concentration on the removal of DDE --- p.34 / Chapter 2.3.2.2 --- Effects of inoculum size on the removal of DDE --- p.35 / Chapter 2.3.2.3 --- Effects of incubation time on the removal of DDE --- p.35 / Chapter 2.3.2.4 --- Transcription of the ligninolytic enzyme-coding genes --- p.35 / Chapter 2.4 --- Treatment of DDE by 1st SMC of p. pulmonarius grown on straw-based compost --- p.36 / Chapter 2.4.1 --- Optimization of DDE removal in soil system --- p.36 / Chapter 2.5 --- Treatment of DDE by crude enzyme preparations of P. pulmonarius grown on straw-based compost --- p.36 / Chapter 2.5.1 --- Optimization of DDE removal in broth system --- p.36 / Chapter 2.5.1.1 --- Effects of initial DDE concentration on the removal of DDE --- p.37 / Chapter 2.5.1.2 --- Effects of amounts of crude enzyme preparations on the removal of DDE --- p.37 / Chapter 2.5.1.3 --- Effects of incubation time on the removal of DDE --- p.37 / Chapter 2.5.2 --- Optimization of DDE removal in soil system --- p.37 / Chapter 2.5.2.1 --- Effects of initial DDE concentration on the removal of DDE --- p.38 / Chapter 2.5.2.2 --- Effects of amount of crude enzyme preparations on the removal of DDE --- p.38 / Chapter 2.5.2.3 --- Effects of incubation time on the removal of DDE --- p.38 / Chapter 2.6 --- Soil characterization --- p.39 / Chapter 2.6.1 --- Identification of organic contaminants in soil sample from Gene Garden using Gas Chromatography/Mass Spectrometry (GC/MS) --- p.39 / Chapter 2.6.2 --- Determination of soil texture --- p.42 / Chapter 2.6.3 --- Fresh soil/air-dried sample moisture --- p.44 / Chapter 2.6.4 --- "Soil pH, electrical conductivity & salinity" --- p.44 / Chapter 2.6.5 --- Total organic carbon contents --- p.44 / Chapter 2.6.6 --- Total nitrogen and total phosphorus --- p.44 / Chapter 2.6.7 --- Available nitrogen --- p.45 / Chapter 2.6.8 --- Available phosphorus --- p.45 / Chapter 2.6.9 --- Potassium value --- p.46 / Chapter 2.7 --- Quantification of residual DDE level --- p.47 / Chapter 2.7.1 --- Preparation of DDE stock solution --- p.47 / Chapter 2.7.2 --- Extraction and quantification of DDE using Gas Chromatography with Electron Capture Detector (GC/μECD) --- p.47 / Chapter 2.7.3 --- Identification of DDE breakdown products by GC/MS --- p.50 / Chapter 2.8 --- Extraction of protein and ligninolytic enzymes --- p.53 / Chapter 2.8.1 --- Protein assay --- p.53 / Chapter 2.8.2 --- Laccase assay --- p.53 / Chapter 2.8.3 --- Manganese peroxidase assay --- p.54 / Chapter 2.8.4 --- Calculation of activity and specific activity of laccase and manganese peroxidase --- p.54 / Chapter 2.9 --- Estimation of fungal biomass --- p.55 / Chapter 2.9.1 --- Preparation of ergosterol standard solution --- p.56 / Chapter 2.9.2 --- Analysis of ergosterol content --- p.56 / Chapter 2.10 --- Expression of the ligninolytic enzyme-coding genes --- p.58 / Chapter 2.10.1 --- Preparation of ribonuclease free reagents and apparatus --- p.58 / Chapter 2.10.2 --- RNA isolation and purification --- p.58 / Chapter 2.10.3 --- cDNA synthesis --- p.59 / Chapter 2.10.4 --- Semi-quantification of ligninolytic enzyme-coding gene expression by RT-PCR --- p.59 / Chapter 2.11 --- Preparation of crude enzyme preparations from P. pulmonarius compost --- p.63 / Chapter 2.12 --- "Assessment criteria: removal efficiency, RE, and removal capacity, RC" --- p.63 / Chapter 2.13 --- Statistical analysis “ --- p.64 / Chapter Chapter III --- Results --- p.65 / Chapter 3.1 --- Soil characterization --- p.65 / Chapter 3.2 --- Cultivation and the expression of the ligninolytic enzyme-coding genes during solid-state-fermentation of edible mushroom Pleurotus pulmonarius --- p.66 / Chapter 3.2.1 --- Mushroom yield --- p.66 / Chapter 3.2.2 --- Protein content --- p.66 / Chapter 3.2.3 --- Specific ligninolytic enzymes activities --- p.66 / Chapter 3.2.4 --- Ergosterol content --- p.69 / Chapter 3.2.5 --- Ligninolytic enzymes productivities --- p.69 / Chapter 3.2.6 --- Expression of the ligninolytic enzyme-coding genes during solid-state-fermentation --- p.72 / Chapter 3.3 --- Treatment of DDE by living P. pulmonaruis --- p.78 / Chapter 3.3.1 --- Optimization of DDE removal in broth system --- p.78 / Chapter 3.3.1.1 --- Effects of initial DDE concentration on the removal of DDE --- p.78 / Chapter 3.3.1.1.1 --- Effects of DDE on biomass development --- p.78 / Chapter 3.3.1.1.2 --- Protein content --- p.78 / Chapter 3.3.1.1.3 --- Specific ligninolytic enzyme activities --- p.78 / Chapter 3.3.1.1.4 --- Ligninolytic enzyme productivities --- p.79 / Chapter 3.3.1.1.5 --- DDE removal and removal capacity --- p.79 / Chapter 3.3.1.2 --- Effects of inoculum sizes on the removal of DDE --- p.84 / Chapter 3.3.1.2.1 --- Effects of DDE on biomass development --- p.84 / Chapter 3.3.1.2.2 --- Protein content --- p.84 / Chapter 3.3.1.2.3 --- Specific ligninolytic enzyme activities --- p.85 / Chapter 3.3.1.2.4 --- Ligninolytic enzyme productivities --- p.85 / Chapter 3.3.1.2.5 --- DDE removal and removal capacity --- p.85 / Chapter 3.3.1.3 --- Effects of incubation time on the removal of 4.0 mM DDE/g biomass --- p.89 / Chapter 3.3.1.3.1 --- Effects of DDE on biomass development --- p.89 / Chapter 3.3.1.3.2 --- Protein content --- p.89 / Chapter 3.3.1.3.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.89 / Chapter 3.3.1.3.4 --- DDE removal and removal capacity --- p.90 / Chapter 3.3.1.3.5 --- Putative degradation derivatives --- p.90 / Chapter 3.3.1.3.6 --- Expression of the ligninolytic enzyme-coding genes during the removal of 4.0 mM DDE/g biomass --- p.94 / Chapter 3.3.1.4 --- Effects of incubation time on the removal of 10.0 mM DDE/g biomass --- p.100 / Chapter 3.3.1.4.1 --- Effects of DDE on biomass development --- p.100 / Chapter 3.3.1.4.2 --- Protein content --- p.100 / Chapter 3.3.1.4.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.100 / Chapter 3.3.1.4.4 --- Expression of the ligninolytic enzyme-coding genes during the removal of 10.0 mM DDE/g biomass --- p.102 / Chapter 3.3.2 --- Optimization of DDE removal in soil system --- p.107 / Chapter 3.3.2.1 --- Effects of initial DDE concentration on the removal of DDE --- p.107 / Chapter 3.3.2.1.1 --- Ergosterol content --- p.107 / Chapter 3.3.2.1.2 --- Protein content --- p.107 / Chapter 3.3.2.1.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.107 / Chapter 3.3.2.1.4 --- DDE removal and removal capacity --- p.108 / Chapter 3.3.2.2 --- Effects of inoculum sizes on the removal of DDE --- p.111 / Chapter 3.3.2.2.1 --- Ergosterol content --- p.111 / Chapter 3.3.2.2.2 --- Protein content --- p.111 / Chapter 3.3.2.2.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.111 / Chapter 3.3.2.2.4 --- DDE removal and removal capacity --- p.112 / Chapter 3.3.2.3 --- Effects of incubation time on the removal of DDE --- p.115 / Chapter 3.3.2.3.1 --- Ergosterol content --- p.115 / Chapter 3.3.2.3.2 --- Protein content --- p.115 / Chapter 3.3.2.3.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.115 / Chapter 3.3.2.3.4 --- DDE removal and removal capacity --- p.116 / Chapter 3.3.2.3.5 --- Putative degradation derivatives --- p.116 / Chapter 3.3.2.4 --- Transcription of the ligninolytic enzyme-coding genes --- p.121 / Chapter 3.4 --- Treatment of DDE by 1st SMC of p. pulmonarius grown on straw-based compost --- p.127 / Chapter 3.4.1 --- Optimization of DDE removal in soil system --- p.127 / Chapter 3.4.1.1 --- Effects of initial DDE concentration on the removal of DDE --- p.127 / Chapter 3.4.1.1.1 --- Ergosterol content --- p.127 / Chapter 3.4.1.1.2 --- Protein content --- p.127 / Chapter 3.4.1.1.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.127 / Chapter 3.4.1.1.4 --- DDE removal and removal capacity --- p.128 / Chapter 3.4.1.2 --- Effects of inoculum sizes on the removal of DDE --- p.132 / Chapter 3.4.1.2.1 --- Ergosterol content --- p.132 / Chapter 3.4.1.2.2 --- Protein content --- p.132 / Chapter 3.4.1.2.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.132 / Chapter 3.4.1.2.4 --- DDE removal and removal capacity --- p.133 / Chapter 3.4.1.3 --- Effects of incubation time on the removal of DDE --- p.136 / Chapter 3.4.1.3.1 --- Ergosterol content --- p.136 / Chapter 3.4.1.3.2 --- Protein content --- p.136 / Chapter 3.4.1.3.3 --- Specific ligninolytic enzyme activities and ligninolytic enzyme productivities --- p.136 / Chapter 3.4.1.3.4 --- DDE removal and removal capacity --- p.137 / Chapter 3.4.1.3.5 --- Putative degradation derivatives --- p.137 / Chapter 3.5 --- Treatment of DDE by crude enzyme preparations of P. pulmonarius grown on straw-based compost --- p.142 / Chapter 3.5.1 --- The crude enzyme preparations of P. pulmonarius grown on straw-based compost --- p.142 / Chapter 3.5.2 --- Optimization of DDE removal in broth system --- p.143 / Chapter 3.5.2.1 --- Effects of initial DDE concentration on the removal of DDE --- p.143 / Chapter 3.5.2.2 --- Effects of amounts of crude enzyme preparations on the removal of DDE --- p.145 / Chapter 3.5.2.3 --- Effects of incubation time on the removal of DDE --- p.147 / Chapter 3.5.2.4 --- Putative degradation derivatives --- p.147 / Chapter 3.5.3 --- Optimization of DDE removal in soil system --- p.151 / Chapter 3.5.3.1 --- Effects of initial DDE concentration on the removal of DDE --- p.151 / Chapter 3.5.3.2 --- Effects of amounts of crude enzyme preparations on the removal of DDE --- p.151 / Chapter 3.5.3.3 --- Effects of incubation time on the removal of DDE --- p.154 / Chapter 3.5.3.4 --- Putative degradation derivatives --- p.154 / Chapter Chapter IV --- Discussions --- p.158 / Chapter 4.1 --- Quantification of the expression of the ligninolytic enzyme-coding genes --- p.158 / Chapter 4.2 --- Artificial cultivation and the expression of the ligninolytic enzyme-coding genes during solid-state-fermentation of edible mushroom Pleurotus pulmonarius --- p.164 / Chapter 4.3 --- Treatment of DDE by living P. pulmonarius --- p.166 / Chapter 4.3.1 --- Optimization of DDE removal in broth system --- p.166 / Chapter 4.3.2 --- Optimization of DDE removal in soil system --- p.169 / Chapter 4.3.3 --- Phylogeny of the ligninolytic enzyme-coding genes --- p.170 / Chapter 4.3.3.1 --- Laccase coding genes --- p.170 / Chapter 4.3.3.2 --- MnP coding genes --- p.175 / Chapter 4.3.4 --- Transcription of the ligninolytic enzyme-coding genes --- p.178 / Chapter 4.4 --- Treatment of DDE by 1st SMC of P. pulmonarius grown on straw-based compost --- p.183 / Chapter 4.4.1 --- Optimization of DDE removal in soil system --- p.183 / Chapter 4.5 --- Treatment of DDE by crude enzyme preparations of P. pulmonarius grown on straw-based compost --- p.184 / Chapter 4.6 --- Cost-effectiveness of the bioremediation method --- p.185 / Chapter 4.7 --- Further investigations --- p.194 / Chapter Chapter V --- Conclusions --- p.197 / References --- p.199

Student Number : 0110574V - MPh research report - School of Public Health - Faculty of Health Sciences / Pesticide poisoning poses a health risk to individuals throughout the world although the reported global and local risk are not consistent in the literature. Mpumalanga Province has areas of epidemic malaria. Spray teams, applying local insecticides to indoor surfaces operate just prior to the rainy season (October to May) to control malaria. The purpose of this cross sectional study was to compare prescribed safe handling and application practices of Mpumalanga malaria spray operators mixing and applying insecticides versus actual practices in the field. All members of the spray operating teams were included in the study. A tick list and questionnaire was utilized to observe field practices and enquire about reasons for non-compliance. Only 28% of all operators complied with prescribed safety practices and differences in compliance between mixing (38%) and application (36%) were marginal. Gloves, face shields and dust masks were not utilized as recommended and contributed to the highest levels of non-compliance. Compliance was found to be dependent on gender, age, years of experience, education level and employment status. The low compliance rate necessitates further investigation of the malaria programme occupational safety management system. All stakeholders need to be aware of the consequences of pesticide poisoning and collaborate in efforts to work towards prevention rather than cure.