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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Estudos bioecológicos de Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) para o controle de Diaphorina citri Kuwayama, 1907 (Hemiptera: Psyllidae) / Bioecological studies on Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) in the control of Diaphorina citri Kuwayama, 1907 (Hemiptera: Psyllidae)

Mariuxi Lorena Gómez Torres 08 April 2009 (has links)
Desde 2004 foram detectadas, nas áreas citrícolas paulistas, as bactérias responsáveis pela principal doença de citros no mundo, o huanglongbing ou greening. A ampla distribuição no Brasil do psilídeo vetor, Diaphorina citri e a presença do patógeno nas áreas citrícolas é um fator limitante à produção. Tamarixia radiata é o principal agente de controle biológico de D. citri. Assim, os objetivos do presente estudo foram: a) realizar o levantamento populacional de T. radiata nas regiões citrícolas do estado São Paulo; b) caracterizar o policromismo em populações do parasitóide provenientes das principais regiões citrícolas do estado; c) estudar a biologia de T. radiata em condições de laboratório; d) avaliar a capacidade de parasitismo em diferentes temperaturas; e) determinar, mediante liberações em pomares cítricos comerciais, a eficiência de T. radiata para o controle de D. citri; f) determinar a ocorrência e efeitos no parasitismo da associação T. radiata - Wolbachia; g) realizar o zoneamento agroecológico de D. citri e T. radiata com base nas exigências térmicas e higrométricas para o estado de São Paulo. As populações de T. radiata coletadas em Itirapina, Pederneiras, Piracicaba e São Carlos apresentaram variações cromáticas em relação à espécie típica, sendo que as regiões ITS1 e ITS2 do rDNA das populações analisadas apresentaram de 98 a 99% de identidade. Assim, estas variações cromáticas estão relacionadas à plasticidade fenotípica intra-específica, própria de populações que se encontram em processo de adaptação ecológica. Em 24 horas, o maior parasitismo foi obtido nas temperaturas de 25 e 30°C. Este parasitóide desenvolveu-se na faixa térmica de 15 a 35°C, sendo que 25°C foi a temperatura mais adequada por proporcionar maior viabilidade do período ovo-adulto e os maiores valores da taxa liquida de reprodução (Ro) e da razão finita de aumento (). No município de Araras, oito dias após a liberação, a porcentagem de parasitismo de T. radiata se manteve entre 51,57 e 72,75%. Nos municípios de Cordeirópolis e Limeira, após três liberações, a porcentagem de parasitismo variou entre 30 e 60%. As populações coletadas em Cafelândia, Ribeirão Bonito e Piracicaba apresentaram infecção múltipla por Wolbachia. O limite térmico inferior de desenvolvimento (Tb) foi de 7,13°C e a constante térmica de 188,7GD. Mediante um Sistema de Informação Geográfica, foram obtidos mapas de distribuição do desenvolvimento de T. radiata e D. citri. Assim, ao longo do ano podem ocorrer, na região norte, de 10 a 13 ciclos de D. citri e de 31 a 35 ciclos de T. radiata; na região nordeste, o número de ciclos pode variar de 6 a 10 e de 24 a 31 para a praga e para o parasitóide, respectivamente; nas regiões sudoeste e sudeste, o número de gerações pode variar de 3 a 10 e de 19 a 31 para D. citri e T. radiata. Verificando estes aspectos da interação T. radiata e D. citri, os dados obtidos no presente trabalho poderão auxiliar para a implementação de um programa de controle biológico, como parte do manejo de D. citri, em regiões ecologicamente distintas do estado de São Paulo. / Since 2004, have been detected in citrus-growing areas of São Paulo, the bacterias that are responsible for the main disease of citrus worldwide, known as greening or huanglongbing. The widespread distribution in Brazil of the vector psyllid, Diaphorina citri and the presence of the pathogen in citrus-growing areas is a limiting factor for production. Tamarixia radiata is the most important biological control agent against D. citri. Therefore, the objectives of this study were to: a) conduct a population survey of T. radiata in the citrus-growing regions of the State of São Paulo; b) characterize polychromism in populations of the parasitoid from the main growing regions in the State of São Paulo; c) study the biology of T. radiata under laboratory conditions; d) evaluate the parasitism capacity at different temperatures; e) determine, by means of releases in commercial citrus orchards, the effectiveness of T. radiata for the control of D. citri; f) determine the occurrence and effects on parasitism of the T. radiata - Wolbachia association; g) prepare an agroecological zoning of D. citri and T. radiata for the State of São Paulo based on their temperature and humidity requirements. T. radiata populations collected in Itirapina, Pederneiras, Piracicaba, and São Carlos showed chromatic variations in relation to the typical species; the ITS1 and ITS2 rDNA regions of the populations analyzed had between 98 and 99% identity. Consequently, these chromatic variations are related to the intraspecific phenotypic plasticity characteristic of populations that are undergoing a process of ecological adaptation. In a 24-hour period, the highest parasitism of T. radiata was obtained at 25 and 30°C. This parasitoid developed in the temperature range from 15 to 35°C; the most suitable temperature was 25°C, since it gave the highest viability for the egg-adult period, and the highest net reproductive rate (Ro) and finite rate of increase values (). In the municipality of Araras, T. radiata parasitism percentage values eight days after release remained between 51.57 and 72.75%. In the areas selected in the municipalities of Cordeirópolis and Limeira, the parasitism percentage of T. radiata after three releases ranged between 30 and 60%. The populations collected in Cafelândia, Ribeirão Bonito, and Piracicaba showed multiple infections by Wolbachia. The parasitoids lower temperature development threshold (Tb) was 7.13°C, with a thermal constant of 188.7 GDD. Distribution maps for T. radiata and D. citri development in the State of São Paulo were obtained by means of a Geographic Information System (GIS). According to those, from 10 to 13 D. citri cycles and from 31 to 35 T. radiata cycles may occur in the northern region over the course of one year; in the northeastern region, the numbers of cycles may vary from 6 to 10 and from 24 to 31 for the pest and the parasitoid, respectively; in the southwest and southeast regions the numbers of generations may vary from 3 to 10 and from 19 to 31 for D. citri and T. radiata. Based on these aspects of the T. radiata × D. citri interaction, the data obtained in this work can be useful for the implement a biological control program as part of D. citri management in ecologically distinct regions of the State of São Paulo.
132

Distribuição espacial e temporal de percevejos da soja e comportamento de piezodorus guildinii (westwood, 1837) (hemiptera: pentatomidae) na soja (glycine max (l.) merrill) ao longo do dia / Spatial and temporal distribution of soybean stink bug and behavior of piezodorus guildinii (westwood, 1837) (hemiptera: pentatomidae) on soybean (glycine max (l.) merrill) on day time

Roggia, Rejane Cristina Roppa Kuss 27 February 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / From december 2006 to april 2008 was conducted a experiment at Universidade Federal de Santa Maria, Santa Maria, RS, Brasil, with objective to verify spatial and temporal distribution of soybean stink bug, with georeferenced surveying. The samplings was accomplished in area of 6,64 hectares of soybean (Glycine max (L.) Merrill), it was divided in a sample grid of the 105 points, spaced in 25 x 25 m. Colonization of the field occurred on soybean s vegetative period, from its adjacent borders to the fields of early soybean and sunflower, by the adults entry from these crops to the experimental area, because later sowing. From the beginning seed until the pod filling of the soybean, the tendency of stink bug population increase by the borders was kept. In the crop 2007/08, due to the sowing have been carried through at that recommended period, the spatial distribution of stink bugs started simultaneously in several points in the field and it did not present clear influence of the adults entry from other areas. In both the crops the populations increase occurred from beginning pod and beginning seed and to species abundance and its population s peaks varied of a crop for another. During overwintering it verified presence of stink bug in the area, feeding itself in the straw on the soil and living on grains fallen into the harvest, or in alternative host plants as Raphanus sp. With objective to study nymphs and adults of Piezodorus guildinii (Westwood, 1837) (Hemiptera: Pentatomidae) behavior on day time on soybean, was conducted a experiment at Universidade Federal de Santa Maria, from april to may 2007. The experimental design employed was a factorial of order fourth, in randomized complete block design (24x3x3x3) (day time x distribution x location x behavior), with five blocks. The stink bugs were observed hourly, during 24 times. The stink bugs plant distribution (top, middle and botton), their location in plant organs (pod, leaf ou HRPR stem, branch, stick or raceme) and their behavior (resting, locomotion, feeding ativity) was registered. During the first and second instars, the nymphs had presented gregarious habit, and a small percentage in movement around of the posture. The nymphs started the feeding activity on second instar, and the locomotion was just around of the posture and the same organ where they were. From the third instar nymphs became more active, with bigger ditribution on plant and feeding more frequently. Locomotion times were near and precedents to feeding times and precedent the dusk, indicating the search for preferential locations for feeding or shelter. Nimphs and adults P. guildinii located preferentially in pod, them whats are associated to repose and feeding activity behaviors. In the nocturnal period, with air temperature lower than in the diurnal period, P. guildinii s nymphs had remained in stems circled by pods, because of the search by sheltered locations. Percentage P. guildinii in feeding activity increased of 7,37% of second-fourth instar for 16,92% in the fifth instar, and 34,77% adult phase. P. guildinii remained, preferentially, in middle plants stracta along the day time, not presenting a clear behavior of distribution in superior plants stracta in defined chedules. Thus, should not be indicated groups ideal schedule's for insecticides application for your control. / De dezembro de 2006 a abril de 2008 foi conduzido um experimento na Universidade Federal de Santa Maria, Santa Maria, RS, Brasil, com o objetivo de verificar a distribuição espacial e temporal de percevejos da soja, através de levantamento georreferenciado. As amostragens foram realizadas em uma área de 6,64 hectares de soja (Glycine max (L.) Merrill) dividida em uma grade amostral com 105 pontos, espaçados em 25 x 25 m. A colonização da lavoura ocorreu no período vegetativo da soja, a partir das bordas adjacentes a lavouras de soja precoce e girassol, pela entrada de percevejos adultos destes cultivos do entorno para a área georreferenciada, em função da semeadura tardia. Desde o início do enchimento de grãos até o enchimento pleno de grãos, a tendência de aumento populacional de percevejos pelas bordas foi mantida. Na safra 2007/08, devido a semeadura ter sido realizada na época recomendada, a distribuição espacial dos percevejos começou simultaneamente em vários pontos na lavoura e não apresentou clara influência da entrada de adultos de outras áreas. Em ambas as safras o aumento das populações ocorreu a partir da formação de legumes e do início do enchimento de grãos e a abundância de espécies e seus picos populacionais variaram de uma safra para outra. Durante todo o período de entressafra, verificou-se a presença de percevejos na área, abrigados na palhada sobre o solo e alimentando-se de grãos caídos na colheita, ou em plantas hospedeiras alternativas como Raphanus sp. Com o objetivo de estudar o comportamento de ninfas e adultos de Piezodorus guildinii (Westwood, 1837) (Hemiptera: Pentatomidae) ao longo do dia em soja, foi conduzido um experimento na Universidade Federal de Santa Maria, de abril a maio de 2007. O delineamento experimental foi um fatorial de quarta ordem em blocos ao acaso (24x3x3x3) (horários x distribuição x localização x comportamentos), com cinco repetições. Os percevejos foram observados de hora em hora, por 24 horas. Registrou-se a sua distribuição nas plantas (terço superior, médio e inferior), a sua localização nos órgãos (legumes, folhas e HRPR haste, ramo, pecíolo ou racemo) e o seu comportamento (repouso, movimento e atividade alimentar). Durante o primeiro e segundo ínstares, as ninfas apresentaram hábito gregário, e uma pequena percentagem de ninfas em movimento em torno da postura. As ninfas começaram a alimentar-se no segundo ínstar, e tornaram-se mais ativas a partir do terceiro ínstar, movimentando-se não só a pequenas distâncias entre órgãos próximos, mas distribuindo-se pelos terços da planta, e alimentando-se mais regularmente. Os horários de movimento foram próximos e antecedentes aos horários de atividade alimentar, e do anoitecer, indicando a procura por locais para alimentação ou abrigo. Ninfas e adultos de P. guildinii localizaram-se preferencialmente em legumes, os quais estão associados aos comportamentos de repouso e atividade alimentar. No período noturno, com a temperatura do ar mais baixa que no período diurno, ninfas de P. guildinii se localizaram em hastes circundadas por legumes, em função da busca por locais abrigados. A percentagem de P. guildinii em atividade alimentar aumentou de 7,37% do segundo ao quarto ínstar para 16,92% no quinto ínstar, e 34,77% na fase adulta. P. guildinii permaneceu, preferencialmente, no terço médio das plantas ao longo do dia, não apresentando um comportamento claro de distribuição no terço superior das plantas em intervalos de horários definidos. Desta forma, não devem ser indicadas faixas de horário ideais para a aplicação de inseticidas para seu controle.
133

Maternal effects in the large milkweed bug Oncopeltus fasciatus

Newcombe, Devi Isadora Ramayanti January 2013 (has links)
Maternal effects are the non-genetic contributions of mothers (or fathers) towards the phenotype of their offspring. Maternal effects are now well recognised as a facilitator for evolutionary change in offspring phenotypes and life history strategies which can have effects on population dynamics, population divergence and even speciation. Furthermore, maternal effects have been shown to have a heritable genetic basis and that they are genetically variable, which suggests that they contribute to maintaining phenotypic variation. Maternal effects may impede or accelerate responses to selection which has implications for adaptive evolution and making predictions about their evolutionary potential. The importance of their contribution to phenotypic variation and life history evolution has made maternal effects an important consideration in fields such as conservation and population biology, evolutionary ecology and evolutionary genetics. The aim of this thesis is to investigate if maternal effects can influence offspring life history traits and fitness parameters through maternal resources via the egg. Main questions that are asked include: can maternal effects help facilitate transition to a novel host-diet (Chapter 2); does maternal diet influence egg composition and, if so, does this have an effect on offspring life-history parameters (Chapter 3); is there a genetic basis to egg composition and is there potential for egg composition to evolve (Chapter 4); and are defensive compounds from the diet transferred into the eggs, if so, are these uni- or biparentally transferred and does this offer protection against predation (Chapter 5)? To address these questions we used a specialist insect herbivore, the large milkweed bug Oncopeltus fasciatus (Hemiptera: Lygaeidae). In the wild, O. fasciatus feed on plants from the genus Asclepias (Apocynacea). However, O. fasciatus can be reared successfully in laboratories on sunflower seeds Helianthus annus. For our experiments we used two populations of O. fasciatus, one population has been maintained on dry seeds of A. syriaca while the other population has been reared and maintained on sunflower seeds. The results of Chapter 2 were suggestive of a maternal host-diet effect on egg mass and hatching success, but we did not find evidence that maternal host-diet was significant in influencing a transition to a novel host. In Chapter 3 we found that there was variation in the free amino acid profiles of the eggs between our treatments suggesting that amino acid profiles may be influenced by maternal diet. The results of our multivariate selection analysis to examine linear and nonlinear (quadratic) relationships between maternal diet and the free amino acid profiles of the eggs suggest that there may be population-specific responses which can influence specific amino acid profiles in relation to hatchling mass. In Chapter 4 we used only the milkweed-adapted population to determine if there was a genetic basis to amino acid profiles in the eggs. We constructed a genetic variance-covariance (G) matrix to determine the strength and direction of the relationships between amino acids and to assess the potential for amino acid profiles to evolve. While we found genetic variation for amino acids, and that there was evidence for positive moderate to strong genetic correlations between many of them, we also found evidence for constraints for the potential for amino acid profiles to evolve as evidenced by the calculation of gmax (which represents the linear combination of components that has the highest genetic variance and which is the most accessible to evolution). In Chapter 5 we found maternal, but not paternal, transmission of cardenolides into the eggs. However, this did not confer protection of all eggs against predation from larvae of the green lacewing Chrysoperla carnea. Overall, results suggest that for our populations of O. fasciatus, maternal effects are significant in influencing early life history traits such as egg mass and hatchling mass. However, we did not find any significant effects on other offspring life history or fitness parameters that we measured. This may be surprising as positive, and negative, effects of non-genetic contributions of females (and males) to their offspring has been widely reported in many taxa. The patterns and implications of maternal resource allocation and their effects on offspring life history evolution are explored and discussed, as are the limitations of our experimental designs. I hope that this research can be used to stimulate further investigations into maternal effects and the relationships between host-plant, maternal allocation strategies and life history evolution.
134

Seasonal abundance and diversity of sorghum panicle-feeding Hemiptera in South Africa / M. Kruger.

Kruger, Marlene January 2006 (has links)
During the past two decades, panicle-feeding Hemiptera have become pests of sorghum in West and Central Africa, and particularly in Mali, where this is a staple food crop. Of the more than 100 sorghum insect pests reported in Africa, 42 species were found to be panicle-feeding pests. Prior to this study, no research had been done on the paniclefeeding Hemiptera in South Africa. The objectives of the study were to determine the abundance and diversity of panicle-feeding Hemiptera on sorghum. A check list was compiled and the temporal distribution of different Hemiptera species determined during the different panicle stages of development. In addition, the effect of insecticide application on Hemiptera numbers was evaluated and the correlation between grain mould severity and Hemiptera feeding damage was investigated. To determine the abundance and diversity of Hemiptera on sorghum panicles, surveys were conducted between November 2004 and June 2006 at 26 sites in four provinces of South Africa. Two methods of collection were used viz. the plastic bag and D-Vac methods. The total number of the adults and nymphs collected during this study was 23 798. Forty-three different herbivorous Hemiptera species were collected. The most abundant family was the Miridae (41 %), followed by the Lygaeidae (17 %). Eurystylus spp., Calidea dregii, Campylomma sp., Creontiades pallidus, Nysius natalensis and Nezara viridula were the most abundant species and also occurred widely in the sorghum production area. Infestation levels of these species were low compared to that in other parts of Africa and it cannot be concluded that they have pest status in South Africa. There was no clear distinction between the stages during which panicles were infested by different species. The general tendency was that nearly all species were present from the flowering stage onwards and that numbers declined when grain hardened. In general, Campylomma sp. and C. pallidus numbers peaked during the flowering stage and Eurystylus spp. and N. natalensis during the milk stage. Hemiptera feeding damage resulted in an increase in incidence of seeds with discoloured germ, therefore contributing significantly to reduction in grain quality. / Thesis (M. Environmental Science (Plant Protection))--North-West University, Potchefstroom Campus, 2007.
135

Seasonal abundance and diversity of sorghum panicle-feeding Hemiptera in South Africa / M. Kruger.

Kruger, Marlene January 2006 (has links)
During the past two decades, panicle-feeding Hemiptera have become pests of sorghum in West and Central Africa, and particularly in Mali, where this is a staple food crop. Of the more than 100 sorghum insect pests reported in Africa, 42 species were found to be panicle-feeding pests. Prior to this study, no research had been done on the paniclefeeding Hemiptera in South Africa. The objectives of the study were to determine the abundance and diversity of panicle-feeding Hemiptera on sorghum. A check list was compiled and the temporal distribution of different Hemiptera species determined during the different panicle stages of development. In addition, the effect of insecticide application on Hemiptera numbers was evaluated and the correlation between grain mould severity and Hemiptera feeding damage was investigated. To determine the abundance and diversity of Hemiptera on sorghum panicles, surveys were conducted between November 2004 and June 2006 at 26 sites in four provinces of South Africa. Two methods of collection were used viz. the plastic bag and D-Vac methods. The total number of the adults and nymphs collected during this study was 23 798. Forty-three different herbivorous Hemiptera species were collected. The most abundant family was the Miridae (41 %), followed by the Lygaeidae (17 %). Eurystylus spp., Calidea dregii, Campylomma sp., Creontiades pallidus, Nysius natalensis and Nezara viridula were the most abundant species and also occurred widely in the sorghum production area. Infestation levels of these species were low compared to that in other parts of Africa and it cannot be concluded that they have pest status in South Africa. There was no clear distinction between the stages during which panicles were infested by different species. The general tendency was that nearly all species were present from the flowering stage onwards and that numbers declined when grain hardened. In general, Campylomma sp. and C. pallidus numbers peaked during the flowering stage and Eurystylus spp. and N. natalensis during the milk stage. Hemiptera feeding damage resulted in an increase in incidence of seeds with discoloured germ, therefore contributing significantly to reduction in grain quality. / Thesis (M. Environmental Science (Plant Protection))--North-West University, Potchefstroom Campus, 2007.
136

Flutuação populacional e distribuição espacial de Diaphorina citri Kuwayama (Hemiptera: Liviidae) em propriedades citrícolas com manejo intensivo do Huanglongbing /

Santos, Tiago Roberto dos. January 2013 (has links)
Orientador: Francisco Jorge Cividanes / Coorientador: José Carlos Barbosa / Banca: Nilza Maria Martinelli / Banca: Pedro Takao Yamamoto / Resumo: O psilídeo asiático dos citros Diaphorina citri Kuwayama (Hemiptera: Liviidae) e, atualmente, considerado a principal praga da citricultura mundial, podendo causar perdas de até 100% na produção. O inseto causa danos diretos, através da sucção de seiva de brotações, contudo sua maior importância está relacionada aos danos indiretos, devido à transmissão da bactéria "Candidatus Liberibacter", associada ao greening ou Huanglongbing (HLB). 0 objetivo deste estudo foi avaliar a flutuação populacional e distribuição espacial de adultos de D. citri em áreas citrícolas do sul e centro do Estado de São Paulo sob controle químico convencional. As avaliações foram realizadas no período de 01 de julho de 2010 a 31 de dezembro de 2012 em duas áreas comerciais de plantio de citros, com 9.004 e 5.495 hectares, localizadas nos municípios de laras e Boa Esperança do Sul, respectivamente. Para a quantificação dos adultos de D. citri, foram instaladas armadilhas adesivas nas bordaduras dos lotes, sendo realizadas avaliações semanais. Os picos populacionais ocorreram na primavera e verão, período com maior número de brotações. As aplicações de inseticidas não alteraram o padrão de distribuição de D. citri. Os valores dos índices de agregação indicaram que o inseto se comporta de maneira altamente agregada na cultura / Abstract: The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is currently considered the major world pest of citriculture and can cause yield losses of up to 100%. The insect causes direct damage by consuming sap from shoots, although its greater importance is related to indirect damage due to the transmission of the bacterium "Candidatus Liberibacter" which are associated to causes the greening or Huanglongbing (HLB). The aim of the study was to evaluate the population fluctuation and spatial distribution of D. citri adults in citrus farming areas of the south and center regions of São Paulo state under conventional chemical control. The evaluations were performed in the period from july 01, 2010 to December 31, 2012 in two areas of citrus commercial planting, with 9,004 and 5,495 hectares, located in the municipalities of laras and Boa Esperança do Sul, respectively. To quantify D. citri adults, yellow sticky traps were assembled on the borders of the lots, and were weekly evaluated by pest inspectors. The population peaks occurred in spring and summer, periods with higher number of new shoots. The insecticides applications did not alter the distribution pattern of D. citri. The values of aggregation index indicated that the insect has a highly aggregate behavior in citriculture / Mestre
137

Flutuação populacional e distribuição espacial de Diaphorina citri Kuwayama (Hemiptera: Liviidae) em propriedades citrícolas com manejo intensivo do Huanglongbing

Santos, Tiago Roberto dos [UNESP] 09 December 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-12-09Bitstream added on 2014-06-13T19:32:17Z : No. of bitstreams: 1 000748805.pdf: 1127265 bytes, checksum: 787fe9a2f6671b14f42cf03ea4bac0d0 (MD5) / O psilídeo asiático dos citros Diaphorina citri Kuwayama (Hemiptera: Liviidae) e, atualmente, considerado a principal praga da citricultura mundial, podendo causar perdas de até 100% na produção. O inseto causa danos diretos, através da sucção de seiva de brotações, contudo sua maior importância está relacionada aos danos indiretos, devido à transmissão da bactéria Candidatus Liberibacter, associada ao greening ou Huanglongbing (HLB). 0 objetivo deste estudo foi avaliar a flutuação populacional e distribuição espacial de adultos de D. citri em áreas citrícolas do sul e centro do Estado de São Paulo sob controle químico convencional. As avaliações foram realizadas no período de 01 de julho de 2010 a 31 de dezembro de 2012 em duas áreas comerciais de plantio de citros, com 9.004 e 5.495 hectares, localizadas nos municípios de laras e Boa Esperança do Sul, respectivamente. Para a quantificação dos adultos de D. citri, foram instaladas armadilhas adesivas nas bordaduras dos lotes, sendo realizadas avaliações semanais. Os picos populacionais ocorreram na primavera e verão, período com maior número de brotações. As aplicações de inseticidas não alteraram o padrão de distribuição de D. citri. Os valores dos índices de agregação indicaram que o inseto se comporta de maneira altamente agregada na cultura / The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is currently considered the major world pest of citriculture and can cause yield losses of up to 100%. The insect causes direct damage by consuming sap from shoots, although its greater importance is related to indirect damage due to the transmission of the bacterium Candidatus Liberibacter which are associated to causes the greening or Huanglongbing (HLB). The aim of the study was to evaluate the population fluctuation and spatial distribution of D. citri adults in citrus farming areas of the south and center regions of São Paulo state under conventional chemical control. The evaluations were performed in the period from july 01, 2010 to December 31, 2012 in two areas of citrus commercial planting, with 9,004 and 5,495 hectares, located in the municipalities of laras and Boa Esperança do Sul, respectively. To quantify D. citri adults, yellow sticky traps were assembled on the borders of the lots, and were weekly evaluated by pest inspectors. The population peaks occurred in spring and summer, periods with higher number of new shoots. The insecticides applications did not alter the distribution pattern of D. citri. The values of aggregation index indicated that the insect has a highly aggregate behavior in citriculture
138

Ocorrência, distribuição espaço-temporal e flutuação da população de percevejos pentatomídeos em sucessões culturais sob pivô central e áreas adjacentes / Ocurrence, spatial and temporal distribution of stink bugs (pentatomidae) population in crops successions under center pivot and adjacent areas

Aguero, Marcos Arturo Ferreira 31 March 2010 (has links)
The stink bugs are pests of soybean, corn, wheat and other crops. Economically, its management and key knowledge and behavior of their populations are needed to plan effective of action. The objective of this research was to investigate the occurrence, spatial-temporal distribution and population fluctuations of species of stink bugs in the succession of crops. The study was conduced during 12/2007 to 11/2009 on Jóia, RS, Brazil, in a commercial farming area of 162ha with no-tillage system, and center pivot irrigation (92ha) and adjacent areas (70ha). In the first year of study, 2007/08, 41ha pivot was planted with soybean [Glycine max (L.) Merrill] and 51ha, with corn (Zea mays L.), while in the offseason of 2008, with 41ha oat (Avena strigosa Schreb) associated with wild radish (Raphanus sativus L.) in succession to soybean and 51ha with oat in corn stubble. In the second year, the 2008/09 crop was planted soybeans in the entire pivot area (92ha) and adjacent areas (70ha). Already in the 2009 offseason, was season black oat (Avena sativa L.) in succession to soybean and wheat (Triticum aestivum L.) in the areas adjacent. Through the Campeiro CR-6® Software was generated a thematic map of the research and divided into regular grid of 63 cells 2.5 ha and their centers constituted the sampling points. The points were located with GPS. Samplings were made fortnightly in 2m², surveying vegetation, straw, crop residues and soil surface. Was noted the number of bugs nymphs from second instars and adults. The species were confirmed in the laboratory of Integrated Pest Management (LabMIP).To analyze the occurrence of population were used statistical series of geographical and temporal, is drawing up tables of frequency distribution of the population for each culture of the pivot, surrounding areas and places of refuge. The data were statistically analyzed by software BioEstat5®. We applied the binomial probability test between the populations of stink bugs on crops and surrounding areas to verify the differences in � 0.05 level of significance. To analyze spatial and temporal distribution, we used the CR-Campeiro6 ® generating digital maps of population distribution of stink bugs. To analyze the fluctuation, graphics were elaborated through the Excel® Software. Was quantified the populations of Euschistus heros (Fabricius, 1798), Dichelops furcatus (Fabricius, 1775), Piezodorus guildinii (Westwood, 1837), Nezara viridula (Linnaeus, 1758) and Edessa meditabunda (Fabricius, 1794). During the two years of study, E. heros and D. furcatus was the species most frequent in soybeans. D. furcatus is more common in corn, wheat and oats. P. guildinii occurs frequently in soybeans. Populations of N. viridula and E. meditabunda are less frequent. In the offseason, the bugs shelter in the trash, weeds, wheat, oats, turnip and migrate to the edge of forest vegetation and wetland. Populations of stink occur more frequently in soybean at stage R7.1 and R9, corn in summer and winter grasses. The location of the beginning of planting determines the distribution of the population. Areas sown late have high immigrant populations of bugs crop more developed or already picked. The occurrence, spatial-temporal distribution and population dynamics of stink bugs vary each year, influenced by soybeans, corn, wheat, oat, turnip, the crop successions, culture adjacent, alternative host plant, trash, weeds and management operations. / Os percevejos pentatomídeos são pragas de soja, milho, trigo e outras culturas. Economicamente, seu manejo é fundamental e o conhecimento do comportamento de suas populações é necessário para planejar medidas de ação eficientes. O objetivo desta pesquisa foi verificar a ocorrência, distribuição espaço-temporal e flutuação da população de espécies de percevejos, nas sucessões de cultivos e áreas adjacentes. O estudo foi realizado entre 12/2007 e 11/2009 no município de Jóia, RS, Brasil, em uma área agrícola comercial de 162ha com sistema de plantio direto e irrigação via pivô central (92ha) e áreas adjacentes (70ha). No primeiro ano de estudo, safra 2007/08, 41ha do pivô foi cultivado com soja [Glycine max (L.) Merril] e 51ha, com milho (Zea mays L.); já na entressafra de 2008, 41ha com aveia preta (Avena strigosa Schreb) associada com nabo forrageiro (Raphanus sativus L.) em sucessão à cultura de soja e 51ha com aveia preta na palhada do milho. No segundo ano, safra 2008/09, foi cultivada soja na totalidade da área do pivô (92ha) e áreas adjacentes (70ha). Já na entressafra 2009, foi cultivada aveia branca (Avena sativa L.) e preta em sucessão à soja e trigo (Triticum aestivum L.) nas áreas adjacentes do pivô. Através do programa CR-Campeiro 6® foi gerado um mapa temático da área de pesquisa e dividida em grade regular de 63 células de 2,5ha e seus centros constituíram-se nos pontos amostrais. Os pontos foram localizados com sistema de posicionamento global (GPS). Foram realizadas amostragens quinzenalmente em 2m², nas culturas, vegetação, palhada, restos de culturas e superfície do solo. Em planilha de campo anotou-se o número de percevejos adultos e ninfas a partir do segundo ínstar. As espécies foram confirmadas no laboratório de Manejo Integrado de Pragas (LabMIP). Para analisar a ocorrência populacional foram utilizadas séries estatísticas do tipo geográfica-temporal, elaborando-se tabelas de distribuição de frequências da população para cada cultura do pivô, áreas adjacentes e locais de refúgio. Os dados foram submetidos à análise estatística através do programa BioEstat 5®. Aplicou-se o teste binomial de probabilidade entre as populações de percevejos nas culturas e áreas adjacentes para verificar diferenças em nível de 5% de significância. Para analisar distribuição espaço-temporal utilizou-se o programa geoestatístico CR-Campeiro6® gerando mapas digitais de distribuição da população de percevejos. Para analisar a flutuação populacional, foram elaborados gráficos através do programa Excel®. Foram estudadas as populações de Euschistus heros (Fabricius, 1798), Dichelops furcatus (Fabricius, 1775), Piezodorus guildinii (Westwood, 1837), Nezara viridula (Linnaeus, 1758) e Edessa meditabunda (Fabricius, 1794). As espécies de maior ocorrência na safra foram E. heros e D. furcatus, concentrando-se na soja. D. furcatus é mais frequente nas culturas de milho, trigo e aveia. P. guildinii, ocorre com maior frequência na soja. Populações de N. viridula e E. meditabunda são menos freqüentes. Na entressafra, os percevejos abrigam-se na palhada, plantas espontâneas, trigo, aveia, nabo forrageiro e migram para vegetações de borda de mato e banhado. As populações de pentatomídeos ocorrem com maior frequência na cultura de soja nos estádios R7.1 e R9, no milho no verão e em gramíneas no inverno. O local de início do plantio determina a distribuição da população de percevejos. Áreas semeadas tardiamente apresentam elevadas populações de percevejos emigrantes de cultivos mais desenvolvidos ou já colhidos. A ocorrência, distribuição espaço-temporal e flutuação populacional de percevejos variam anualmente, influenciadas pelas sucessões de culturas de soja, milho, trigo, aveia, nabo forrageiro, cultura adjacente, vegetação de refúgio, palhada, plantas daninhas e operações de manejo.
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Can the one true bug be the one true answer? The influence of prairie restoration on Hemiptera composition

Gunter, Stephanie Kay 09 August 2021 (has links)
No description available.
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Distribuição espacial e temporal, inimigos naturais e tabela de vida ecológica de Diaphorina citri Kuwayama (Hemiptera: Psyllidae) em citros em São Paulo / Spatial and seasonal distribution, natural enemies and ecological life table of Diaphorina citri Kuwayama (Hemiptera: Psyllidae) in citrus groves in São Paulo

Paiva, Paulo Eduardo Branco 13 April 2009 (has links)
O \"huanglongbing\" (HLB), ou \"greening\" dos citros, tem sido considerada a pior e mais destrutiva doença que ocorre em cultivares comerciais de citros do mundo. Até hoje, não se conhecem medidas eficientes para o controle da doença. Apesar disso, são recomendadas três medidas que podem reduzir a disseminação da mesma, (1) propagação de material sadio, (2) eliminação de planta sintomática tão logo seja constatada e (3) redução da população do vetor, o psilídeo Diaphorina citri Kuwayama. O HLB foi constatado no Brasil, no estado de São Paulo, em março de 2004. Desde então, foram constatadas duas bactérias associadas a plantas com sintomas, \"Candidatus Liberibacter americanus\" e \"Candidatus Liberibacter asiaticus\", ambas transmitidas por D. citri. A proposta deste trabalho foi estudar: (1) a distribuição temporal deste inseto em pomares comerciais de laranja (Citrus sinensis) nas regiões de Araras, Bauru, Botucatu, Casa Branca, Lins e São Carlos, estado de São Paulo, no período de julho de 2004 a junho de 2007, (2) a distribuição espacial de D. citri em Bauru, Botucatu, Franca, Lins e São Carlos com base na relação variância/média, coeficiente de Taylor e índice de Morisita, (3) inimigos naturais de D. citri e taxas de parasitismo de ninfas do psilídeo por Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) em diferentes pomares, no período de 2005 a 2007 e (4) a tabela de vida ecológica das fases imaturas deste inseto, em Araras e Piracicaba, por quatro gerações. As proporções de ramos de C. sinensis infestados por ninfas e adultos do psilídeo variaram de 0 a 68,3% e se mostraram dependentes da disponibilidade de ramos em crescimento (novos), embora o tamanho da população seja dependente do clima. A maior infestação de ninfas foi observada em São Carlos e as maiores infestações de adultos ocorreram em Bauru, Botucatu, Lins e São Carlos. Por outro lado, as menores proporções de ramos infestados foram observadas em Araras e Casa Branca. D. citri mostrou uma distribuição do tipo agregada, tanto para a fase ninfal quanto para a fase adulta. Não foram observados coccinelídeos predando ovos ou ninfas do psilídeo. A predação de D. citri por crisopídeos foi muito baixa nas condições estudadas. As taxas médias de parasitismo de ninfas, de quarto e quinto ínstares, por T. radiata variaram entre as áreas amostradas e épocas, de 0 a 91,6%, sendo tal parasitismo variável de acordo com a cultivar de citros. Na tabela de vida ecológica, verificou-se que as durações do período de ovo a adulto, em campo, foram semelhantes entre as quatro gerações, de 18,0 a 24,7 dias (temperaturas médias de 21,6 a 26,0°C) e seguiram os modelos de exigências térmicas do inseto obtidos em laboratório. Entretanto, as viabilidades deste mesmo período variaram consideravelmente, de 1,7 a 21,4%, sendo que as maiores mortalidades foram verificadas nas fases de ovo e ninfa pequena (primeiro a terceiro ínstares), as quais são consideradas fatores chaves para o crescimento populacional da praga. / Huanglongbing (HLB), or citrus greening disease, has been considered the worst and most destructive disease that occurs in all citrus varieties in the world. Until today, effective control measures are unknown. However, three main measures have been recommended that may reduce the spread of the disease: (1) propagation of healthy plants; (2) elimination of symptomatic trees as soon as they are observed; and (3) reduction of the insect vector population, the citrus psylla Diaphorina citri Kuwayama. HLB was first found in Brazil in the State of São Paulo in March 2004. Since then, two bacteria were found associated with plants with symptoms, \"Candidatus Liberibacter americanus\" and \"Candidatus Liberibacter asiaticus\", both transmitted by D. citri. This research aimed to study: (1) the seasonal distribution of D. citri in citrus groves (Citrus sinensis) in Araras, Bauru, Botucatu, Casa Branca, Lins and São Carlos, State of São Paulo, from July 2004 through June 2007; (2) the spatial distribution of D. citri in Bauru, Botucatu, Franca, Lins and São Carlos according to the variance/mean ratio, Taylor\'s power law coefficients, and Morisitas index; (3) natural enemies of D. citri and parasitism rates of citrus psylla nymphs by Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) in different groves in three years, 2005, 2006, and 2007; and (4) the ecological life table of the immature stages of this insect, in Araras and Piracicaba, over four generations. The proportions of C. sinensis flushes or branches infested with nymphs and adults of citrus psylla ranged from 0 to 68.3%, and were dependent on the availability of new flushes, although population size depends on the climate. The largest infestation of nymphs was observed in São Carlos and the largest infestations of adults occurred in Bauru, Botucatu, Lins, and São Carlos. On the other hand, the lowest proportions of infested flushes or branches were observed in Araras and Casa Branca. D. citri nymphs and adults showed an aggregate distribution. No coccinellids were observed preying on eggs and nymphs of D. citri. Predation of D. citri by lacewings was very low under the conditions studied. The average parasitism rates of fourth- and fifth-instar nymphs by T. radiata varied among the sampled areas and seasons from 0 to 91.6%, and also varied with citrus variety. In the ecological life table, the mean developmental period from egg to adult in the field was similar between the four generations, 18.0 to 24.7 days (average temperatures of 21.6 to 26.0°C) and values were not different from the thermal requirement models obtained in the laboratory. However, immature survival ranged considerably, from 1.7 to 21.4%, and the highest mortalities were observed in eggs and small nymphs (first to third instars), which are considered the key factors for population growth of the pest.

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