Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2017-04-03T12:25:22Z No. of bitstreams: 1 texto completo.pdf: 2716794 bytes, checksum: 6cbc55ddf42c47a8b94e0bca6edfe45c (MD5) / Made available in DSpace on 2017-04-03T12:25:22Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2716794 bytes, checksum: 6cbc55ddf42c47a8b94e0bca6edfe45c (MD5) Previous issue date: 2004-01-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O manejo de mosca minadora, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae), é uma medida importante como forma de evitar a mudança de status desta praga na cultura do tomateiro. Este trabalho objetivou determinar a unidade amostral que melhor representa a variabilidade de minas com larvas na planta e propor planos de amostragem convencionais e seqüenciais de contagem e de presença-ausência para L. trifolii no tomateiro. A unidade amostral ideal foi determinada com o registro do tempo gasto para a contagem de minas com larvas nas unidades amostrais compostas por uma, duas e três folhas consecutivas ao longo do dossel da planta. Foram calculadas as variâncias relativas das unidades amostrais e realizadas análises de correlação e de regressão linear simples entre o as densidades absolutas (no de minas/terço do dossel e n de minas/planta) e densidades relativas (no de minas/unidade amostral e no de minas/terço do dossel). A unidade amostral com uma folha inserida entre os terços mediano e basal do dossel do tomateiro foi a que melhor representou a variabilidade e o número total de minas de L. trifolii na planta de tomate. Os números de minas de L. trifolii/folha e de folhas infestadas com densidades acima de zero, uma, duas e três minas/folha foram utilizados para se determinar os planos de amostragem. Os dados amostrais foram ajustados ao modelo de distribuição binomial negativo e obtido parâmetro de dispersão comum (Kcomum ). As proporções de unidades amostrais infestadas com densidades acima de zero, uma, duas e três minas/folha foram determinadas com o modelo de probabilidade de distribuição binomial negativa. Os planos de amostragem foram obtidos com o valor de Kcomum igual a 0,835, nível de controle igual a 3,0 minas/folha e os valores das proporções de unidades amostrais infestadas. Os planos convencionais de contagem e de presença-ausência foram determinados aos níveis de erro de 5, 10, 15, 20 e 25%. Os planos de amostragem seqüencial de contagem e de presença-ausência foram determinados através do teste da razão de probabilidade seqüencial de Wald. Foram requeridas 24 e 96 amostras/talhão para a amostragem convencional ao nível de erro de 25% pela contagem do número de minas e avaliação da presença- ausência, respectivamente. Os planos de amostragem seqüencial, através da contagem de minas e da avaliação de presença-ausência foram consistentes, precisos e requereram o máximo de 15 e 27 amostras para tomada de decisão correta, respectivamente. O plano seqüencial de contagem proporcionou uma economia de 37,5% no tempo de amostragem em relação ao plano convencional. Verificaram- se economias de 93, 84, 75 e 66% no tempo de amostragem com os planos seqüenciais de presença-ausência em relação aos planos convencionais com densidades de infestação acima de zero, uma, duas e três minas/folha, respectivamente. Em lavouras com baixas infestações, recomenda-se os planos seqüenciais de presença-ausência com densidades de infestação da amostra acima de zero mina/folha. / The management of leaf miner, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae), is an important tool to avoid the change of status of this insect in the tomato crop. This work aimed to determine the sample unit that best represents the variability of mines with larvae in the plant and to propose conventional and sequential sampling plans with counting and binomial evaluation for L. trifolii in tomatoes. The ideal sample unit was determined considering the time spent for counting mines with larvae in the sample units composed by one, two and three consecutive leaves inserted in the canopy. The relative variance of the sample units were calculated and subjected to correlation and linear regression analyses among the absolute densities (number of mines/ canopy section and number of mines/plant) and relative densities (number of mines/ sample unit and number of mines/ canopy section). The leaf inserted between the medium and basal section of the canopy was the sample unit that best represented the variability and the total number of mines of L. trifolii in the tomato plant. The number of mines of L. trifolii/leaf and the number of leaves infested with densities above zero, one, two and three mines/leaf were used to determine the sampling plans. The sample data were adjusted to binomial negative frequency model and the parameter of common dispersion (K common) was obtained. The proportion of sample units infested with densities above zero, one, two and three mines/leaf were determined using the binomial negative distribution model. The sampling plans were obtained with the Kcommon value of 0,835, economic injury level equal to 3.0 mines/leaf and the proportion values of the sample units infested. The conventional plans of counting and of presence- absence were developed at the error levels of 5, 10, 15, 20 and 25%. The sequential sampling plans of counting and of presence-absence were developed through the Wald Sequential Probability Ratio Test. Twenty four and 96 samples/crop were required for the conventional sampling at the level of error of 25% through the counting of the number of mines and through the evaluation of the presence-absence, respectively. The sequential sampling plans based in the counting of mines and the presence-absence evaluation were consistent, precise and required the maximum of 15 and 27 samples for making correct decisions, respectively. The sequential sample plan by counting provided an economy of 37.5% in the sampling time in relation to the conventional sampling plan. Economies in the sampling time of the 93, 84.75 and 66% were verified with the sequential sampling plan for presence-absence compared with the conventional sampling plans with densities infestations above zero, one, two and three mines/leaf, respectively. In crops with low infestations, the sequential sampling plan based in the presence-absence with densities of sample infestation above zero mines/leaf should be preferred. / Não foi localizado o cpf do autor.

Submitted by (edna.saturno@ufrpe.br) on 2016-11-28T13:24:21Z No. of bitstreams: 1 Marcos Aurelio Araujo Lima.pdf: 265280 bytes, checksum: ad282a74478ab0633f0cbad41f436c79 (MD5) / Made available in DSpace on 2016-11-28T13:24:21Z (GMT). No. of bitstreams: 1 Marcos Aurelio Araujo Lima.pdf: 265280 bytes, checksum: ad282a74478ab0633f0cbad41f436c79 (MD5) Previous issue date: 2008-11-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the last years the leafminer Liriomyza trifolii (Burgess) has become a serious pest on melon crops. To develop a pest management program it is important to know some biological aspects of this insect species. Thus, the objective of this work was to study the biology of L. trifolii, to determine its thermal requirements and its fertility life table reared in melon under different temperatures. The temperatures studied were 20, 22, 25, 28, 30 e 33ºC. Egg hatching occurred within 2.8 (30ºC) to 6.6 (20ºC) days. Larval period ranged from 2.4 to 5.9 days, at 33 and 20ºC, respectively. A variation of 7.8 (33ºC) to 19.7 (20ºC) and 13.1 (33ºC) to 32.2 (20ºC),respectively, was observed for pupal stage and from egg to adult emergence. Larvae viability was always higher than 79%, while pupae viability was always lower than 83%, reaching 35% at 20ºC. The lower threshold temperature for eggs, larvae, pupae and egg-adult periods was 12.46,13.04, 13.20 and 12.95ºC, respectively. Thermal requirement (K) for egg, larva, pupa and from egg laying to adult emergence was 47.98, 41.54, 120.19 and 211.86 degree-days. Based on thermal requirements determined for L. trifolii and average temperatures for Mossoró, Apodi and Jaguaruana were estimated that it’s able to complete up to 23 generations per year in these areas. The mean duration of one generation (T) was 23.68 and 18.15 days, respectively, at thetemperatures of 25 and 28ºC. The net reproductive rate (Ro) was higher at 25ºC, corresponding to an increase of 86.20 times at each generation. The intrinsic rate of population increase (rm) was 0.18 (25ºC) and 0.15 (28ºC) and the finite ratio of population increase ( ) was 1.21(25ºC) and 1.17 (28ºC). The best performance of L. trifolii was at 25ºC. / Nos últimos anos as áreas cultivadas com meloeiro têm apresentado diminuição em sua produtividade devido à ocorrência da mosca-minadora, Liriomyza trifolii (Burgess). Para que se possa realizar um manejo adequado é necessário que se conheçam alguns aspectos biológicos desse inseto. Esta pesquisa teve como objetivos estudar a biologia, determinar as exigências térmicas e tabela de vida de fertilidade de L. trifolii com base nos dados obtidos do desenvolvimento deste inseto nas temperaturas de 20, 22, 25, 28, 30 e 33ºC. A duração do período embrionário variou de 2,8 (30ºC) a 6,6 (20ºC) dias. A duração da fase de larva foi de 2,4 a 5,9 dias, nas temperaturas de 33 e 20ºC, respectivamente. Ocorreu uma variação de 7,8 (33ºC) a 19,7 (20ºC) e 13,1 (33ºC) a 32,2 (20ºC), respectivamente, para a fase de pupa e tempo total de desenvolvimento. A viabilidade da fase de larva foi sempre superior a 79%. A viabilidade pupal foi sempre inferior a 83% e chegando a 38,1% na temperatura de 20ºC. Para as fases de ovo, larva, pupa e ovo-adulto os valores das temperaturas base foram de 12,46, 13,04, 13,20 e 12,95ºC. A constante térmica (K) para as fases de ovo, larva, pupa e tempo total de desenvolvimento foram de 47,98; 41,54; 120,19 e 211,86 graus-dia. Baseados nas exigências térmicas determinadas para L. trifolii e nas normais térmicas para Mossoró, Apodi e Jaguaruana estimou-se que a mesma pode completar mais 23 gerações/ano em ambas as localidades. A duração média da geração (T) foi igual a 23,68 e 18,15 dias, respectivamente, nas temperaturas de 25 e 28ºC. A taxa líquida de reprodução (Ro) foi maior na temperatura de 25ºC, correspondendo a um aumento de 86,20 vezes a cada geração. A taxa líquida de crescimento populacional (rm) foi de 0,18 (25ºC) e 0,15 (28ºC) e a razão finita de aumento ( ) 1,21 (25ºC) e 1,17 (28ºC). Diante de todos os parâmetros biológicos estudados, a melhor temperatura para o desenvolvimento de L. trifolii foi 25ºC.

Atualmente, a mosca-minadora Liriomyza sativae (Diptera: Agromyzidae) é uma das principais pragas da cultura do meloeiro no Brasil. É comumente relatado que as moscas-minadoras se tornam pragas devido a um desequilíbrio biológico provocado pelo uso incorreto de inseticidas além do seu grande potencial biótico. Portanto, é fundamental que sejam desenvolvidas estratégias de manejo que atuem em equilíbrio com o ambiente. Assim, a resistência de plantas a insetos assume papel fundamental nesse contexto. Diante desses fatos, a presente pesquisa objetivou avaliar a resistência de genótipos de meloeiro à mosca-minadora. A criação do inseto foi mantida em plantas de feijão-caupi. Foram realizados ensaios preliminares com diferentes números de casais e diferentes tempos de exposição das plantas aos insetos visando determinar a combinação mais adequada para estudos de resistência. Os resultados indicaram que são necessários quatro casais/planta e um tempo mínimo de infestação de 24 horas. Foram testados inicialmente 44 genótipos divididos em cinco grupos, comparados sempre a uma testemunha suscetível (Vereda). Cada grupo foi mantido numa gaiola onde ocorreu a infestação pelos adultos. Após cinco dias, foi avaliado o número de minas por planta, com base no que foi calculado o Índice de Resistência. A partir desse índice, foram selecionados, os oito genótipos mais promissores (os acessos A5, A15, A22, A29, A42 e A44 e as cultivares Mc Laren e Guaporé) para avaliação dos possíveis tipos de resistência envolvidos. No teste de antixenose para oviposição, constatouse que, no teste de livre escolha, todos os genótipos foram menos preferidos para oviposição que a testemunha, enquanto no teste de confinamento os menos preferidos foram os genótipos A5, A22, A29, A42, A44 e Guaporé. Os genótipos A22, A29, A42, A44 e Mc Laren prolongaram a duração do período embrionário do inseto, enquanto a cultivar Guaporé provocou sobrevivência larval nula e Mc Laren prolongou a fase larval e, juntamente com o acesso A44, reduziu a sobrevivência dessa fase. Por outro lado, o acesso A15 foi o que proporcionou a maior duração da fase de pupa, sendo o tamanho pupal reduzido pelos acessos A29, A42 e A44. A maior duração da fase imatura do inseto ocorreu nos genótipos A29 e Mc Laren. Os diferentes genótipos de meloeiro não influenciaram a longevidade, a razão sexual, os períodos de pré-oviposição e de oviposição e a fecundidade total dos adultos de L. sativae. Com base na avaliação do efeito dos genótipos sobre a biologia do inseto, constatou-se que Mc Laren, Guaporé, A22, A29, A42 e A44 apresentam resistência do tipo antibiose e/ou antixenose para alimentação. No ensaio de tolerância, concluiu-se que a quantidade de clorofila nas folhas foi um parâmetro adequado para caracterizar o efeito do ataque de L. sativae sobre o meloeiro; por outro lado, os pesos de matéria fresca e seca e o comprimento do ramo principal não foram parâmetros adequados para avaliação da tolerância. Considerando todos os parâmetros estudados nesse ensaio, os genótipos A44 e Guaporé se comportaram como tolerantes. / Nowadays, the vegetable leafminer Liriomyza sativae (Blanchard) (Diptera: Agromyzidae) is one of the major melon pests in Brazil. The outbreak of this pest has been frequently reported to be due to biological control disruptions caused by the incorrect use of insecticides and to its high biotic potential. Therefore, it is important that management strategies acting in balance with the environment are developed. Studies on host plant resistance to insects play a fundamental role in this context. In this research project, we intended to evaluate the resistance of melon genotypes to the vegetable leafminer. The insect population was reared under laboratory conditions on bean plants. Preliminary assays were carried out with different numbers of couples and different infestation times aiming to find the most adequate combination to be used in plant resistance studies. The best results were obtained with four couples per plant and 24 hours of infestation. Initially, 44 melon genotypes were screened in five groups of nine genotypes compared to a susceptible control genotype (Vereda). Each group was placed in one cage for infestation with adult leafminer flies. After four days, the mean number of mines per plant was evaluated. Based on this data, the Resistance Index was estimated and eight genotypes were selected (accessions A5, A15, A22, A29, A42 and A44 and cultivars Mc Laren and Guapore). In the oviposition preference study, all genotypes were less preferred than the control in the multiple-choice test while in the no-choice test genotypes A5, A22, A29, A42, A44 and Guaporé was less preferred. Egg duration was longer in genotypes A22, A29, A42, A44 and Mc Laren than in control. In Guapore no larvae survived while in A44 and Mc Laren larval survival was smaller than in control, moreover in Mc Laren larval duration was longer than in control. Accession A15 provided the longest pupal duration, while accessions A29, A42 and A44 presented the smallest pupal sizes. In genotypes A29 and Mc Laren the egg-adult period was longer than the control. The different genotypes did not affect longevity, sex ratio, preoviposition and oviposition periods and fecundity of females. Based on the evaluation of host plant effect on the vegetable leafminers biology it was established that the genotypes A22, A29, A42, A44, Mc Laren and Guapore present resistance by antibiosis and/or antixenosis for feeding. In the tolerance test, it was concluded that chlorophyll content was an adequate parameter for discriminating the genotypes in relation to attack by L. sativae; on the other hand, main branch length and fresh and dry weight were not adequate parameters for tolerance study. Based on all parameters evaluated, genotypes A44 and Guapore seems to be tolerant.

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