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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.
1

Effects of multiple generations of Metarhizium anisopliae on subterranean termite feeding and mortality

Engler, Kimberly M. 29 August 2005 (has links)
This thesis evaluated the attractancy and mortality of Metarhizium anisopliae on two species of subterranean termites, Reticulitermes flavipes (Kollar) and Coptotermes formosanus Shiraki. There were four specific objectives developed for this research. The first objective was to determine if R. flavipes or C. formosanus were attracted to the mycelium mat matrix of M. anisopliae cultured on rice or corn. The second objective was to determine the tunneling distances of R. flavipes and C. formosanus when exposed to aged strains of M. anisopliae. The third objective was to determine if the fungus caused mortality to populations of R. flavipes or C. formosanus in glass tube bioassays. The fourth objective was to determine if R. flavipes termites are attracted to an ethanol extract of mycelium of M. anisopliae (X-5) or a commercial preferred feeding product (Summon??), and to estimate the percent consumption of the cellulose matrix. The extract and the Summon?? disks were tested in the laboratory using glass plate bioassays, and in the field using commercial termite monitors containing each of the treatments individually. The results with attractancy and mortality varied with age and generation of M. anisopliae mycelia, but all treatments were more attractive and caused more mortality than the controls. When presented with choices, both R. flavipes and C. formosanus did show preference to both the mycelium and the extract forms of M. anisopliae. The 1:1000 dilution of M. anisopliae extract (X-5) was strongly preferred over the other treatments, and all of the dilutions were preferred over the Summon?? and ethanol (40%) treated disks in the laboratory. An analysis of the consumption of test cellulose matrix showed that Summon?? did not attract termites, but it was a phagostimulant. When the undiluted ethanol extract of M. anisopliae was tested in the field, there were more termite visits to the ethanol extract of M. anisopliae (X-5) treated monitors stations, and the fewest termite visits were observed in the monitors containing the untreated fiber pulp disks.
2

Effects of multiple generations of Metarhizium anisopliae on subterranean termite feeding and mortality

Engler, Kimberly M. 29 August 2005 (has links)
This thesis evaluated the attractancy and mortality of Metarhizium anisopliae on two species of subterranean termites, Reticulitermes flavipes (Kollar) and Coptotermes formosanus Shiraki. There were four specific objectives developed for this research. The first objective was to determine if R. flavipes or C. formosanus were attracted to the mycelium mat matrix of M. anisopliae cultured on rice or corn. The second objective was to determine the tunneling distances of R. flavipes and C. formosanus when exposed to aged strains of M. anisopliae. The third objective was to determine if the fungus caused mortality to populations of R. flavipes or C. formosanus in glass tube bioassays. The fourth objective was to determine if R. flavipes termites are attracted to an ethanol extract of mycelium of M. anisopliae (X-5) or a commercial preferred feeding product (Summon??), and to estimate the percent consumption of the cellulose matrix. The extract and the Summon?? disks were tested in the laboratory using glass plate bioassays, and in the field using commercial termite monitors containing each of the treatments individually. The results with attractancy and mortality varied with age and generation of M. anisopliae mycelia, but all treatments were more attractive and caused more mortality than the controls. When presented with choices, both R. flavipes and C. formosanus did show preference to both the mycelium and the extract forms of M. anisopliae. The 1:1000 dilution of M. anisopliae extract (X-5) was strongly preferred over the other treatments, and all of the dilutions were preferred over the Summon?? and ethanol (40%) treated disks in the laboratory. An analysis of the consumption of test cellulose matrix showed that Summon?? did not attract termites, but it was a phagostimulant. When the undiluted ethanol extract of M. anisopliae was tested in the field, there were more termite visits to the ethanol extract of M. anisopliae (X-5) treated monitors stations, and the fewest termite visits were observed in the monitors containing the untreated fiber pulp disks.
3

Parasitism of Subterranean Termites (Isoptera: Rhinotermitidae: Termitidae) by Entomopathogenic Nematodes (Nematoda: Steinernematidae: Heterorhabditidae)

Yu, Hao January 2009 (has links)
The biological control of subterranean termites (Isoptera: Rhinotermitidae; Termitidae) using entomopathogenic nematodes (Nematoda: Steinernematidae; Heterorhabditidae) (EPN) was investigated. The desert subterranean termite Heterotermes aureus Snyder was found to be very susceptible to Steinernema riobrave Cabanillas, Poinar and Raulston. In laboratory bioassays S. riobrave (355, TP, 3-8b and 7-12 strains), S. carpocapsae Weiser (Mexican 33 strain), S. feltiae Filipjev (UK76 strain), and Heterorhabditis bacteriophora Poinar (HP88 strain) were all capable of infecting and killing H. aureus, Reticulitermes flavipes Kollar, R. virginicus Banks, Coptotermes formosanus Shiraki and Gnathamitermes perplexus Banks. In sand assays, S. riobrave caused > 90% H. aureus mortality in 3 days and 100% mortality by day 5 at 22 °C. TP strain of S. riobrave caused 75% R. flavipes mortality and 90.91% C. formosanus mortality in 7 days. EPNs utilizing termites as hosts produced smaller sized offspring, with the exception of S. feltiae. Stunted females of S. feltiae were frequently found in termite cadavers, but no progeny. Small IJs of S. carpocapsae, S. riobrave and H. bacteriophora infect, reproduce and form normal size IJs after subsequent infection in Galleria mellonella L. The progeny of small IJs were as effective as the normal size IJs, with regard to subsequent induced mortality, under the conditions tested. In laboratory two-container choice experiments, H. aureus were repelled by EPN treated areas for up to 10 days at 10,000 IJs per device. The repellency threshold was found to vary among nematodes species. We hypothesis that it is the physical movement of the nematodes that repels the termites. Temperature is a key factor affecting nematode pathogenicity. Temperature tolerance of the nematodes varied between species. After a gradual heat adaptation process, S. riobrave and H. bacteriophora caused significantly higher H. aureus mortality at 32 °C compared with original laboratory cultured strains. Further work may result in the contribution of commercially available strains with enhanced heat tolerance. Preliminary field studies confirmed EPN protection of a structure, however, termites began to reinfest 4 weeks after the application. Additional tests are necessary to provide more evidence before we can conclude nematodes as useful in the field.
4

The effects of boron-treated timbers against coptotermes species in Australia

Ahmed, Berhan Mahmoud Unknown Date (has links) (PDF)
In Australia the protection of building timbers from termites relied for many years upon the application of persistent organochlorines as well as the organophosphate compound (chlorpyrifos) and the synthetic pyrethroid (bifenthrin) as soil chemical barriers (Lenz et al. 1990; Watson, 1990; NHMRC, 1992; AS 3660.1 1995). The persistent organochlorines have been banned since 1987 in the USA and from June 1995 in all Australian states except the Northern Territory. The study evaluated the life-cycle of boron as an alternative wood preservative, its toxicity to foraging populations of subterranean termites (‘termites’) over time were particularly referred to the influence of foraging space and determined a suitable loading of boron in timber for hazard class2 (H2) conditions as defined in Australian standard-1997. Preservative treatment of timber according to Australian Standard 1604 (1997) prevents attack and damage of wood and wood products from biodeteriogens (namely fungi and insects). Above-ground interior timber framings are not normally liable to decay but to damage by wood-destroying insects. The study examined the use of borates as wood preservatives to prevent attack and damage by subterranean termites (‘termites’) of the genus of Coptotermes. In addressing the aims of this study, several different avenues of approach were followed. The chapter sequence in this thesis follows the pattern of measuring the effects of borates on a wide range from 20 termites in laboratory bioassay to thousands of termites in natural colonies.
5

Patogenicidade de Paecilomyces farinosus sobre Coptotermes gestroi e parâmetros biológicos

LOPES, Rosineide da Silva January 2007 (has links)
Made available in DSpace on 2014-06-12T15:06:29Z (GMT). No. of bitstreams: 2 arquivo4621_1.pdf: 3366454 bytes, checksum: 0f8d7fbcd9aea57e993d99f860f0e9f1 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O cupim asiático, Coptotermes gestroi, é considerado praga nas áreas urbanas, causando danos expressivos em casas, edifícios e árvores. Esta pesquisa avaliou a patogenicidade de Paecilomyces farinosus URM4993 e Paelomyces farinosus URM4995 sobre operários de C. gestroi. Os insetos foram pulverizados nas concentrações de 104 a 108 conídios/mL, mantidos em BOD a 25ºC e 80% de umidade relativa e determinada a Concentração Letal (CL50) e Tempo Letal (TL50). Foi avaliada a produção de conídios sobre os insetos mortos e analisados os aspectos biológicos referentes à germinação, esporulação, crescimento radial e microestruturas, antes e após a infecção em C. gestroi. O fungo foi patogênico ao cupim, causando mortalidade em todas as concentrações utilizadas, sendo que P. farinosus URM4993 foi mais virulenta, apresentando mortalidade de 100%, após o 6º dia de inoculação (CL50 de 4,86 x 105 conídios/mL e TL50 de 2,26 dias). A esporulação nos insetos mortos não diferiu entre as linhagens. O percentual de germinação foi maior nas linhagens reisoladas. P. farinosus URM4993 apresentou maior esporulação do que P. farinosus URM4995. O crescimento micelial de P. farinosus URM4995 foi maior do que seu reisolado, a partir do 9º dia de análise. Não foram observadas diferenças morfológicas das linhagens após a passagem pelo hospedeiro. Esses resultados demonstraram a patogenicidade e virulência das linhagens testadas, sendo que P. farinosus URM4993 foi mais eficiente, indicando seu potencial para o biocontrole de C. gestroi
6

Estudo taxonômico e aspectos da biologia de Coptotermes Wasmann, 1896 (Isoptera, Rhinotermitidae) nas Américas. / Study of the taxonomy and biology of Coptotermes Wasmann, 1896 (Isoptera, Rhinotermitidae) in the Americas.

Ferraz, Marisa Vianna 30 November 2000 (has links)
Coptotermes (Isoptera: Rhinotermitidae) é um gênero de grande importância econômica que, no sudeste do Brasil, é responsável pela maioria dos estragos em materiais celulósicos. Nenhum estudo taxonômico havia sido feito anteriormente, para as espécies das Américas e, até o momento, apenas cinco espécies eram conhecidas na região. Este gênero, com distribuição pantropical, apresenta cerca de 80 espécies descritas no mundo e, por ser um grupo grande e bastante diversificado, existe uma carência de trabalhos de revisão taxonômica e a identificação das espécies é, freqüentemente, uma tarefa difícil. No presente trabalho, foi feito o estudo taxonômico do gênero Coptotermes, nas Américas. Além das cinco espécies conhecidas, C. havilandi, C. formosanus, C. testaceus, C. crassus e C. niger, reconheço agora 13 novos táxons, que apresento aqui como espécies novas. Juntamente com as descrições, acrescentei dados de morfometria, desenhos esquemáticos, imagens de microscopia eletrônica de varredura, mapas com a distribuição geográfica e chaves de identificação de todas as espécies, com exceção de C. niger, pois não pude examinar os tipos, nem identificar qualquer amostra, com certeza, como sendo desta espécie. Achei preferível manter tal nome e a descrição traduzida de SNYDER (1922), mas não posso afirmar que se trata de uma boa espécie por falta de dados. Apesar da grande quantidade de material estudado (730 amostras), grandes áreas geográficas, em especial a região norte e nordeste do Brasil e outros países da América do Sul, ainda carecem de material representativo. Com a realização de coletas mais extensivas, acredito que este número possa duplicar. Foi dada ênfase no estudo de Coptotermes havilandi, principal praga de madeiras do sudeste brasileiro. Para esta espécie, foi feito o estudo da biologia das colônias iniciais, observando-se o comportamento pós-revoada, escolha do substrato de nidificação, taxa de sobrevivência das colônias, tempo de pré-postura, período de incubação dos ovos, tempo de duração e taxa de mortalidade entre os instares dos operários, muda e porcentagem da casta de soldados, número e viabilidade de indivíduos por colônia e rejeição das câmaras de criação, pelos reprodutores. Os resultados do estudo da biologia evidenciam a grande plasticidade de C. havilandi, no estabelecimento de novas colônias, em diversos tipos de substratos, até mesmo nos considerados pouco propícios e, também, sem a necessidade de contato com o solo. Também foi feito o estudo da fenologia das revoadas desta espécie, na cidade de São Paulo, destacando a sazonalidade e horário das revoadas, assim como razão sexual dos alados. Sua capacidade de fazer revoadas esporádicas, fora do período de pico (entre agosto e outubro), durante quase todo o ano, além de sua ampla distribuição horária, evidenciam a alta plasticidade de C. havilandi na dispersão dos indivíduos e a grande capacidade reprodutiva da espécie, com a produção de alados durante quase o ano inteiro. Por último, foi feita a descrição do ninho desta espécie, que mostrou um padrão semelhante a outras descrições feitas previamente, para esta e outras espécies do gênero. / Coptotermes (Isoptera: Rhinotermitidae) is a genus economically important, responsible for most of the damage to wood in southeastern Brazil. No taxonomic study on American species is available, and so far only five species have been described in the Americas. Coptotermes has a pantropical distribution, with approximately 80 species described worldwide. Taxonomic reviews for this genus are scarse and the identification of species of this diversified group is often difficult. This work is a taxonomic study of the genus Coptotermes in the Americas. In addition to the five described species, C. havilandi, C. formosanus, C. testaceus, C. crassus and C. niger, I describe thirteen new taxa that are presented as new species. Together with the descriptions of species I include morphometric data, schematic drawings, scanning electron microscopy pictures, maps of the distribution of each species and an identification key for all species except C. niger, for which I could not examine the types neither identify samples with certainty. Therefore, I chose rather to retain the name and description given by SNYDER (1922), although I cannot show that it is actually a good species. Despite the high number of samples analyzed (730) representative data from big geographical areas, especially north and northeastern Brazil and the other countries of South America are still lacking. More extensive collects in these areas potentially can double the number of the known Coptotermes species in the Americas. I focused on the study of C. havilandi, which is the main pest of wood in southeastern Brazil. The biology of incipient colonies has been studied, recording post-swarming behavior, nest choice, survival rate of colonies, duration of pre-oviposition, incubation time for eggs, each instar’s duration, death rate between worker instars, moulting and proportion of soldiers, number and viability of individuals per colony, and rejection from reproductive chambers by the reproductives. The study of the biology shows the high plasticity of C. havilandi to founding colonies in different types of substrates, including some considered as poorly suitable and some lacking contact with the soil. The study of the phenology of swarms in São Paulo city reveals the seasonality and timing of swarms, as well as the sexual ratio of alates. The capacity to produce sporadic dispersal flights (i.e. out of the peak period from August to October) almost year round and during a large part of the day demonstrate the high plasticity of C. havilandi in its dispersal habit and high reproductive capacity. Finally, I describe the nest of C. havilandi, showing a similar pattern to previous descriptions for this and other species of the genus.
7

Estudo taxonômico e aspectos da biologia de Coptotermes Wasmann, 1896 (Isoptera, Rhinotermitidae) nas Américas. / Study of the taxonomy and biology of Coptotermes Wasmann, 1896 (Isoptera, Rhinotermitidae) in the Americas.

Marisa Vianna Ferraz 30 November 2000 (has links)
Coptotermes (Isoptera: Rhinotermitidae) é um gênero de grande importância econômica que, no sudeste do Brasil, é responsável pela maioria dos estragos em materiais celulósicos. Nenhum estudo taxonômico havia sido feito anteriormente, para as espécies das Américas e, até o momento, apenas cinco espécies eram conhecidas na região. Este gênero, com distribuição pantropical, apresenta cerca de 80 espécies descritas no mundo e, por ser um grupo grande e bastante diversificado, existe uma carência de trabalhos de revisão taxonômica e a identificação das espécies é, freqüentemente, uma tarefa difícil. No presente trabalho, foi feito o estudo taxonômico do gênero Coptotermes, nas Américas. Além das cinco espécies conhecidas, C. havilandi, C. formosanus, C. testaceus, C. crassus e C. niger, reconheço agora 13 novos táxons, que apresento aqui como espécies novas. Juntamente com as descrições, acrescentei dados de morfometria, desenhos esquemáticos, imagens de microscopia eletrônica de varredura, mapas com a distribuição geográfica e chaves de identificação de todas as espécies, com exceção de C. niger, pois não pude examinar os tipos, nem identificar qualquer amostra, com certeza, como sendo desta espécie. Achei preferível manter tal nome e a descrição traduzida de SNYDER (1922), mas não posso afirmar que se trata de uma boa espécie por falta de dados. Apesar da grande quantidade de material estudado (730 amostras), grandes áreas geográficas, em especial a região norte e nordeste do Brasil e outros países da América do Sul, ainda carecem de material representativo. Com a realização de coletas mais extensivas, acredito que este número possa duplicar. Foi dada ênfase no estudo de Coptotermes havilandi, principal praga de madeiras do sudeste brasileiro. Para esta espécie, foi feito o estudo da biologia das colônias iniciais, observando-se o comportamento pós-revoada, escolha do substrato de nidificação, taxa de sobrevivência das colônias, tempo de pré-postura, período de incubação dos ovos, tempo de duração e taxa de mortalidade entre os instares dos operários, muda e porcentagem da casta de soldados, número e viabilidade de indivíduos por colônia e rejeição das câmaras de criação, pelos reprodutores. Os resultados do estudo da biologia evidenciam a grande plasticidade de C. havilandi, no estabelecimento de novas colônias, em diversos tipos de substratos, até mesmo nos considerados pouco propícios e, também, sem a necessidade de contato com o solo. Também foi feito o estudo da fenologia das revoadas desta espécie, na cidade de São Paulo, destacando a sazonalidade e horário das revoadas, assim como razão sexual dos alados. Sua capacidade de fazer revoadas esporádicas, fora do período de pico (entre agosto e outubro), durante quase todo o ano, além de sua ampla distribuição horária, evidenciam a alta plasticidade de C. havilandi na dispersão dos indivíduos e a grande capacidade reprodutiva da espécie, com a produção de alados durante quase o ano inteiro. Por último, foi feita a descrição do ninho desta espécie, que mostrou um padrão semelhante a outras descrições feitas previamente, para esta e outras espécies do gênero. / Coptotermes (Isoptera: Rhinotermitidae) is a genus economically important, responsible for most of the damage to wood in southeastern Brazil. No taxonomic study on American species is available, and so far only five species have been described in the Americas. Coptotermes has a pantropical distribution, with approximately 80 species described worldwide. Taxonomic reviews for this genus are scarse and the identification of species of this diversified group is often difficult. This work is a taxonomic study of the genus Coptotermes in the Americas. In addition to the five described species, C. havilandi, C. formosanus, C. testaceus, C. crassus and C. niger, I describe thirteen new taxa that are presented as new species. Together with the descriptions of species I include morphometric data, schematic drawings, scanning electron microscopy pictures, maps of the distribution of each species and an identification key for all species except C. niger, for which I could not examine the types neither identify samples with certainty. Therefore, I chose rather to retain the name and description given by SNYDER (1922), although I cannot show that it is actually a good species. Despite the high number of samples analyzed (730) representative data from big geographical areas, especially north and northeastern Brazil and the other countries of South America are still lacking. More extensive collects in these areas potentially can double the number of the known Coptotermes species in the Americas. I focused on the study of C. havilandi, which is the main pest of wood in southeastern Brazil. The biology of incipient colonies has been studied, recording post-swarming behavior, nest choice, survival rate of colonies, duration of pre-oviposition, incubation time for eggs, each instar’s duration, death rate between worker instars, moulting and proportion of soldiers, number and viability of individuals per colony, and rejection from reproductive chambers by the reproductives. The study of the biology shows the high plasticity of C. havilandi to founding colonies in different types of substrates, including some considered as poorly suitable and some lacking contact with the soil. The study of the phenology of swarms in São Paulo city reveals the seasonality and timing of swarms, as well as the sexual ratio of alates. The capacity to produce sporadic dispersal flights (i.e. out of the peak period from August to October) almost year round and during a large part of the day demonstrate the high plasticity of C. havilandi in its dispersal habit and high reproductive capacity. Finally, I describe the nest of C. havilandi, showing a similar pattern to previous descriptions for this and other species of the genus.
8

Termite baiting system technology: utilization and evaluation for integrated management of Reticulitermes flavipes (Kollar) and Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) subterranean termite populations, with seasonal variation and spatial patterns exhibited in foraging strategies

Glenn, Grady J. 12 April 2006 (has links)
Commercial termite baiting systems were utilized and evaluated under real-world conditions in order to provide a comparison of efficacy in the management of subterranean termites. Three commercial termite baiting systems available for comparison included: FirstLine® (FMC Corp.), Sentricon® (Dow AgroSciences), and Terminate® (United Industries, Inc). The time required for foraging termites to locate and begin feeding on both the Sentricon® and the Terminate® bait stations was approximately one-half the time required to locate and begin feeding on the FirstLine® system, for both R. flavipes and C. formosanus. The time required for C. formosanus to locate and begin feeding on all termite baiting systems was approximately one-half the time required for R. flavipes. There were no significant differences in efficacy between the three baiting treatment systems against R. flavipes, with a mean of 84% efficacy for all systems. The Sentricon® system was able to achieve efficacy (88%) results with few additional residual liquid termiticide treatments. FirstLine® efficacy (80%) and Terminate® efficacy (84%) results required initial and subsequent multiple spot treatments with residual termiticide for comparable results. The Sentricon® baiting system yielded positive results in the management of C. formosanus, if utilized in an aggressive, active management program, involving multiple supplementary in-ground and above-ground bait stations at both points of active infestation and at areas with conditions conducive to infestation. Optimum results were achieved when monitoring of the bait stations occurred twice each month, rather than the standard monthly monitoring regime. The two termite baiting systems with Sulfluramid as the active ingredient required spot treatments with termiticides in order to protect the structures. Grids of bait stations were installed and termite activity and foraging strategies were monitored for a five-year period. Treatment with sulfluramid required 472 active ingredient tubes, over a 37-month period, in order to reduce subterranean termite populations. Observations of seasonal variation and spatial patterns of foraging by native subterranean termites, R. flavipes, in a typical urban/suburban setting provided information with direct application to an effective termite baiting system program.
9

Termite baiting system technology: utilization and evaluation for integrated management of Reticulitermes flavipes (Kollar) and Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) subterranean termite populations, with seasonal variation and spatial patterns exhibited in foraging strategies

Glenn, Grady J. 12 April 2006 (has links)
Commercial termite baiting systems were utilized and evaluated under real-world conditions in order to provide a comparison of efficacy in the management of subterranean termites. Three commercial termite baiting systems available for comparison included: FirstLine® (FMC Corp.), Sentricon® (Dow AgroSciences), and Terminate® (United Industries, Inc). The time required for foraging termites to locate and begin feeding on both the Sentricon® and the Terminate® bait stations was approximately one-half the time required to locate and begin feeding on the FirstLine® system, for both R. flavipes and C. formosanus. The time required for C. formosanus to locate and begin feeding on all termite baiting systems was approximately one-half the time required for R. flavipes. There were no significant differences in efficacy between the three baiting treatment systems against R. flavipes, with a mean of 84% efficacy for all systems. The Sentricon® system was able to achieve efficacy (88%) results with few additional residual liquid termiticide treatments. FirstLine® efficacy (80%) and Terminate® efficacy (84%) results required initial and subsequent multiple spot treatments with residual termiticide for comparable results. The Sentricon® baiting system yielded positive results in the management of C. formosanus, if utilized in an aggressive, active management program, involving multiple supplementary in-ground and above-ground bait stations at both points of active infestation and at areas with conditions conducive to infestation. Optimum results were achieved when monitoring of the bait stations occurred twice each month, rather than the standard monthly monitoring regime. The two termite baiting systems with Sulfluramid as the active ingredient required spot treatments with termiticides in order to protect the structures. Grids of bait stations were installed and termite activity and foraging strategies were monitored for a five-year period. Treatment with sulfluramid required 472 active ingredient tubes, over a 37-month period, in order to reduce subterranean termite populations. Observations of seasonal variation and spatial patterns of foraging by native subterranean termites, R. flavipes, in a typical urban/suburban setting provided information with direct application to an effective termite baiting system program.
10

Patogenicidade de fungos do gênero Isaria (Persoon) sobre Coptotermes gestroi (Wasmann) (Isoptera : Rhinotermitidae) e aspectos imunológicos / Pathogenicity of the fungi genus Isaria (Persoon) on Coptotermes gestroi (Wasmann) (Isoptera : Rhinotermitidae) and immunologic aspects

PASSOS, Eliana Maria dos 02 February 2009 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-11-24T12:55:10Z No. of bitstreams: 1 Eliana Maria dos Passos.pdf: 388635 bytes, checksum: e5d6eb95c9d3a471c040f1951f046959 (MD5) / Made available in DSpace on 2016-11-24T12:55:10Z (GMT). No. of bitstreams: 1 Eliana Maria dos Passos.pdf: 388635 bytes, checksum: e5d6eb95c9d3a471c040f1951f046959 (MD5) Previous issue date: 2009-02-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The termite Coptotermes gestroi (Wasmann) is an urban and agricultural pest that has been established in many areas of the world. The use of entomopathogenic fungi is an option to minimize the economic loss caused by this termite. It is known, however, that physiological disorders caused by a pathogen trigger defence reactions of the insects, such as humoral and cellular responses (hemocytes). Thus, this research had as objectives: 1. to verify the pathogenicity of Isaria farinosa and I. fumosorosea to the termite C. gestroi and 2. to qualify and quantify the hemocytes in workers of this insect challenged by the pathogenic and virulent isolates. All fungi isolates tested, in the concentration of 107 conidia mL-1, were pathogenic and virulent causing more than 60% mortality, with an average survival of 2.0 to 3.9 days. However, the isolate URM-4995 of I. farinosa was one of the most virulent, being selected for the LC50 determination, estimated at 6.7 x 105 conidia mL-1, and to study the cellular immune response.The total average of hemocytes found in the hemolymph of workers termites treated with that isolate, in the concentration of 107 conidia mL-1, was not different from the hemocytes average recorded for the control, within 12, 24, 36 and 48 hours intervals. Regarding the cell types, the analysis in light microscopy revealed that the most frequent cells were plasmatocytes. The differential counts in infected and uninfected insects, did not differ significantly within the timeintervals assessed, there was only a change in function of time for plasmatocytes and prohemocytes. Thus, the results of total and differential counts show that I. farinosa in the concentration 107 conidia mL-1, did not affect quantitatively and qualitatively in the number of hemocytes of C. gestroi and that this pathogen appears as a promising candidate for controllingthis insect. / O cupim Coptotermes gestroi (Wasmann) é uma praga urbana e agrícola que vem se estabelecendo em muitas áreas do mundo. A utilização de fungos entomopatogênicos é uma opção para minimizar os prejuízos econômicos causados por este cupim. Sabe-se, contudo, que distúrbios fisiológicos ocasionados por um patógeno desencadeiam reações de defesa pelos insetos, como respostas humorais e celulares (hemócitos). Desta forma, a presente pesquisa teve como objetivos: 1. verificar a patogenicidade de isolados de Isaria farinosa e Isaria fumosorosea ao cupim C. gestroi e 2. avaliar qualitativamente e quantitativamente os hemócitos em operários deste inseto desafiado por isolado patogênico e virulento. Todos isolados se mostraram patogênicos, na concentração 107 conídios mL-1, ocasionando mortalidades acima de 60% e virulentos, apresentando uma sobrevivência média de 2,0 a 3,9 dias. Porém, o isolado URM-4995 de I. farinosa destacou-se como um dos mais virulentos, sendo selecionado para a determinaçãoda CL50, estimada em 6,7 x 105 conídios mL-1, e estudo da resposta imunológica celular. A média total de hemócitos encontrada na hemolinfa de operários tratados com este isolado, na concentração de 107 conídios mL-1, não foi diferente da média de hemócitos registradas para a testemunha, nos intervalos de 12h, 24h, 36h e 48h. Com relação aos tipos celulares, a análise em microscopia de luz revelou que as células mais frequentes foram plasmatócitos A contagem diferencial nos insetos infectados e não infectados, não diferiu significativamente nos intervalos de tempo avaliado, constatou-se somente uma variação em função do tempo para os plasmatócitos e prohemócitos. Assim, os resultados das contagens total e diferencial apresentados demonstram que I. farinosa, na concentração 107 conídios mL-1, não interferiu quantitativamente e qualitativamente no número de hemócitos de C. gestroi e que tal patógeno apresenta-se como promissor para o controle deste inseto.

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