Made available in DSpace on 2016-08-12T19:18:24Z (GMT). No. of bitstreams: 1 ALAN MARTINS DE OLIVEIRA.pdf: 1485830 bytes, checksum: 11c6b8c6119b924bac2704d8a0abf2f0 (MD5) Previous issue date: 2008-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work aims to analyze technical and environmental aspects of the production of melon in the Homogeneous Zone in Mossoró emphasizing the fitosanitary control of the whitefly and Leaf Miner Fly. It is divided in two parts. In the Chapter I, an experiment was installed in Baraúna-RN, using delineation in blocks at random, in pieces subdivided in the time 6 x 5. There were six treatments in the piece: 1-physical control (blanket) chemist; 2-physical control (manta) + natural (oil of neem); 3-physical control (manta) + chemist + natural + peat (oil of neem); 4-physical control (manta) + chemist + peat + biological (trichoderma); 5-chemical control; 6-testifies. There were five times of evaluation in the sub piece of pest infestation: 20°, 28°, 36°, 44° and 52° DAT Days After the transplanting. Quantitative characteristics were analyzed: counting of nymphs and adults of whitefly and, larvae and adults of Leaf Miner Fly; qualitative characteristics in the fruits: mass, soluble solids, pulp firmness and pH. The use of alternative methods: biological, physical, natural control and peat have positive effects when used in the associate form. So, it is possible to reduce the use of pesticides in the melon. In the Chapter II, it was used like methodological proceedings the exploratory and descriptive search. There were valued data of questionnaires devoted to the owners or managers of the producing enterprises of melon, through probabilistic sample. It was checked that the short cycle of the culture, the model based on the monoculture, the agricultural mechanization, the elevated consumption of energy and the use of pesticides and chemical fertilizers associated to the marketing demands of qualitative and quantitative characteristics of the results, are affecting the sustainability of the culture of melon. In the final considerations, we realize that the technologies and the developed methods of production, aiming to pay attention to the growing demand of the result, especially of the rich countries, are untenable in the environmental optics; besides proposing larger searches aiming the sustainability: economical growth with ecological care and social equity / Este trabalho objetiva analisar aspectos técnicos e ambientais da produção de melão na Zona Homogênea Mossoroense, com ênfase ao controle fitossanitário das mosca-branca e mosca-minadora. Está dividido em duas partes. No Capítulo I, instalou-se um experimento em Baraúna-RN, usando delineamento em blocos ao acaso, em parcelas subdivididas no tempo 6 x 5. Na parcela constaram seis tratamentos: 1- controle físico (manta) + químico; 2- controle físico (manta) + natural (óleo de nim); 3- controle físico (manta) + químico + turfa + natural (óleo de nim); 4- controle físico (manta) + químico + turfa + biológico (trichoderma); 5- controle químico; 6- testemunha. Na subparcela constaram cinco tempos de avaliação de infestação de pragas: 20º, 28°, 36°, 44° e 52° DAT Dias Após o Transplantio. Analisaram-se características quantitativas: contagem de ninfas e adultos de mosca-branca e, larvas e adultos de mosca-minadora; características qualitativas nos frutos: massa, sólidos solúveis, firmeza de polpa e pH. O uso de métodos alternativos: controle biológico, físico, natural e turfa têm eficiência quando usados de forma associada. Assim, é possível reduzir o uso de agrotóxicos no melão. No Capítulo II, utilizou-se como procedimentos metodológicos a pesquisa exploratória e descritiva. Avaliou-se dados de questionários aplicados aos proprietários ou gestores das empresas produtoras de melão, por meio de amostragem probabilística. Verificou-se que o ciclo curto da cultura, o modelo baseado na monocultura, a mecanização agrícola, o elevado consumo de energia e o uso de agrotóxicos e fertilizantes químicos, associados às exigências mercadológicas de características quali-quantitativas dos frutos, estão afetando a sustentabilidade da atividade meloeira. Nas considerações finais, destaca-se que as tecnologias e os métodos de produção desenvolvidos, visando atender à crescente demanda do fruto, notadamente dos países ricos, são insustentáveis na ótica ambiental; além de propor pesquisas mais abrangentes quanto aos princípios norteadores da sustentabilidade: crescimento econômico com prudência ecológica e eqüidade social

Horticulture is a major foreign exchange earner in Kenya and provides employment to approximately 75% of the population. However, the growth of the horticultural industry is constrained by pests such as the leafminer flies, Liriomyza sativae, L. trifolii and L. huidobrensis (Diptera: Agromyzidae). These pests do not only cause damage to crops, but are also tagged as quarantine pests, resulting in export rejections, loss of export markets and consequently loss of revenue to smallholders. The management of leafminers worldwide has commonly relied on the use of chemical insecticides, but due to associated negative effects thereof, biological control using parasitoids and entomopathogenic fungi has been proposed as major components of integrated pest management (IPM) strategies. The indigenous ectoparasitoid Diglyphus isaea and exotic endoparasitoid Phaedrotoma scabriventris are the two key natural enemies being considered. A number of endophytic fungal isolates have been identified with potential for use as biological control agents of pests. Although there have been previous reports on toxicity of fungal endophytes to leafminers, no attempts have been made to exploit them for control of Liriomyza leafminers. The objectives of this study were to investigate the mechanisms by which fungal endophytes control Liriomyza spp., as well as the interactions between these endophytic fungi and the L. huidobrensis, endoparasitoid Phaedrotoma scabriventris and ectoparasitoid Diglyphus isaea. This study showed that under laboratory conditions, while used separately, parasitism rates of L. huidobrensis by D. isaea and P. scabriventris were 63.6 ± 7.7% and 30.4 ± 10.9% respectively and increased to 77.0 ± 5.3% when used simultaneously. In addition, both parasitoids induced leafminer mortality through larval-feeding and stinging. In order to identify and characterize endophytic fungi that could possibly be used for control of these pests, fungi were isolated from the aboveground parts of maize, sorghum, Napier grass, Coleopteran larvae and Busseola fusca pupae. Identified fungi were evaluated endophytically in two host plants species (Phaseolus vulgaris and Vicia faba) through seed inoculation. The fungal isolates that succeeded in colonizing the host plants were all pathogenic to L. huidobrensis, causing 100% mortality within 13.2 ± 0.7-15.0 ± 0.6 days. They were also able to reduce the longevity of the progeny, the number of pupae and adult emergence and survival. In addition, results also showed that endophytically-inoculated and L. huidobrensis-infested V. faba plants had no adverse effects on parasitism rates and life history parameters of P. scabriventris and D. isaea. Bio-prospecting for fungal endophytes in P. vulgaris and V. faba seeds, followed by morphological and molecular identification revealed the presence of various species of fungal entomopathogens, including Beauveria bassiana, Epacris microphylla, Phanerochaete chrysosporium and Metarhizium anisopliae. / PhD (Environmental Sciences), North-West University, Potchefstroom Campus, 2013

Horticulture is a major foreign exchange earner in Kenya and provides employment to approximately 75% of the population. However, the growth of the horticultural industry is constrained by pests such as the leafminer flies, Liriomyza sativae, L. trifolii and L. huidobrensis (Diptera: Agromyzidae). These pests do not only cause damage to crops, but are also tagged as quarantine pests, resulting in export rejections, loss of export markets and consequently loss of revenue to smallholders. The management of leafminers worldwide has commonly relied on the use of chemical insecticides, but due to associated negative effects thereof, biological control using parasitoids and entomopathogenic fungi has been proposed as major components of integrated pest management (IPM) strategies. The indigenous ectoparasitoid Diglyphus isaea and exotic endoparasitoid Phaedrotoma scabriventris are the two key natural enemies being considered. A number of endophytic fungal isolates have been identified with potential for use as biological control agents of pests. Although there have been previous reports on toxicity of fungal endophytes to leafminers, no attempts have been made to exploit them for control of Liriomyza leafminers. The objectives of this study were to investigate the mechanisms by which fungal endophytes control Liriomyza spp., as well as the interactions between these endophytic fungi and the L. huidobrensis, endoparasitoid Phaedrotoma scabriventris and ectoparasitoid Diglyphus isaea. This study showed that under laboratory conditions, while used separately, parasitism rates of L. huidobrensis by D. isaea and P. scabriventris were 63.6 ± 7.7% and 30.4 ± 10.9% respectively and increased to 77.0 ± 5.3% when used simultaneously. In addition, both parasitoids induced leafminer mortality through larval-feeding and stinging. In order to identify and characterize endophytic fungi that could possibly be used for control of these pests, fungi were isolated from the aboveground parts of maize, sorghum, Napier grass, Coleopteran larvae and Busseola fusca pupae. Identified fungi were evaluated endophytically in two host plants species (Phaseolus vulgaris and Vicia faba) through seed inoculation. The fungal isolates that succeeded in colonizing the host plants were all pathogenic to L. huidobrensis, causing 100% mortality within 13.2 ± 0.7-15.0 ± 0.6 days. They were also able to reduce the longevity of the progeny, the number of pupae and adult emergence and survival. In addition, results also showed that endophytically-inoculated and L. huidobrensis-infested V. faba plants had no adverse effects on parasitism rates and life history parameters of P. scabriventris and D. isaea. Bio-prospecting for fungal endophytes in P. vulgaris and V. faba seeds, followed by morphological and molecular identification revealed the presence of various species of fungal entomopathogens, including Beauveria bassiana, Epacris microphylla, Phanerochaete chrysosporium and Metarhizium anisopliae. / PhD (Environmental Sciences), North-West University, Potchefstroom Campus, 2013