Thesis (Ph. D.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 99-110).

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Mainz, Universiẗat, Diss., 2000.

Thesis (Ph. D.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 99-110). / Also available by subscription via World Wide Web / xii, 110 leaves, bound ill. 29 cm

20 pp.

Background: Symbioses throughout the animal kingdom are known to extend physiological and ecological capabilities to hosts. Insect-microbe associations are extremely common and are often related to novel niche exploitation, fitness advantages, and even speciation events. These phenomena include expansions in host diet, detoxification of insecticides and toxins, and increased defense against pathogens. However, dissecting the contributions of individual groups of symbionts at the molecular level is often underexplored due to methodological and analytical limitations. Termites are one of the best studied systems for physiological collaborations between host and symbiota; however, most work in lower termites (those with bacterial and protist symbionts) focuses on the eukaryotic members of this symbiotic consortium. Here we present a metatranscriptomic analysis which provides novel insights into bacterial contributions to the holobiont of the eastern subterranean termite, Reticulitermes flavipes, in the presence and absence of a fungal pathogen. Results: Using a customized ribodepletion strategy, a metatranscriptome assembly was obtained representing the host termite as well as bacterial and protist symbiota. Sequence data provide new insights into biosynthesis, catabolism, and transport of major organic molecules and ions by the gut consortium, and corroborate previous findings suggesting that bacteria play direct roles in nitrogen fixation, amino acid biosynthesis, and lignocellulose digestion. With regard to fungal pathogen challenge, a total of 563 differentially expressed candidate host and symbiont contigs were identified (162 up-and 401 downregulated; a/FDR = 0.05) including an upregulated bacterial amidohydrolase. Conclusions: This study presents the most complete bacterial metatranscriptome from a lower termite and provides a framework on which to build a more complete model of termite-symbiont interactions including, but not limited to, digestion and pathogen defense.

Resumo: O cupim exótico Coptotermes gestroi (Wasmann, 1896) é a principal praga responsável por danos econômicos nas áreas urbanas da região sudeste do Brasil. No presente estudo foram realizados testes laboratoriais e de campo para avaliar a eficiência dos ingredientes ativos sulfluramida, hidrametilnona, ácido bórico, fipronil, piriproxifen e ciromazina para uso em iscas de controle desse cupim. Inicialmente, foram realizados experimentos em placas de Petri com o objetivo de selecionar as melhores concentrações de baixa toxicidade e que não fossem repelentes ou inibissem a alimentação dos cupins. As concentrações selecionadas foram usadas em uma segunda etapa de testes, nos quais foram utilizados um número maior de cupins. Os experimentos laboratoriais permitiram a seleção das seguintes concentrações para testes em campo: 0,01 ppm de sulfluramida; 200 ppm de hidrametilnona; entre 12.500 e 15.000 ppm de ciromazina; entre 1.000 e 12.500 ppm de piriproxifen; entre 3.000 e 2.000 ppm de ácido bórico. Somente, o ingrediente ativo fipronil não se mostrou adequado para uso em isca, devido à alta mortalidade obtida em todos os experimentos. Previamente aos testes de campo, foram estimados os territórios e as populações forrageiras das colônias de C. gestroi das áreas escolhidas. Os resultados de campo obtidos para C. gestroi nas áreas I (P.S.), II (L.U.) e III (S.O.R.) mostraram que não ocorreu nenhuma repelência ou inibição do consumo do papelão impregnado com os princípios ativos sulfluramida à 0,1 ppm, hidrametilnona à 400 ppm e ciromazina à 15.000 ppm. Contudo, o número de iscas e as concentrações utilizadas destes produtos não foram suficientes para eliminar nenhuma das colônias estudadas. Os resultados também sugerem que, em colônias naturais, as diferentes fontes alimentares exploradas pelos cupins subterrâneos e a competição... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The subterranean termite Coptotermes gestroi (Wasmann, 1896) is a pest of major economic importance in the urban environments of southeastern Brazil. In this study, we performed laboratory and field experiments to evaluate the efficacy of sulfluramid, hydramethylnon, boric acid, fipronil, pyriproxyfen and cyromazine as active ingredients in bait. In the first experiment, we tested different concentrations of these active ingredients in Petri dishes, searching for the best slow-acting and non-repellent concentrations for this termite. Concentrations selected from the initial experiment were used in a second laboratory experiment using a large number of individuals. From the results of this second experiment we selected the following concentrations to be fieldtested: 0.01 ppm of sulfluramid; 200 ppm of hydramethylnon; between 12,500 and 15,000 ppm of cyromazine; between 1,000 and 12,500 ppm of pyriproxyfen; between 3,000 and 2,000 ppm of boric acid. The data displayed a fast mortality of termites exposed to fipronil, even in small concentrations, therefore demonstrating that it is not a suitable chemical to be used in baits against C. gestroi. For field experiments, we estimated population and territory size from three colonies of C. gestroi present at the experimental site. Field results showed no repellence for site I (P.S.), II (L.U.) and III (S.O.R.) using sulfluramid 0.1 ppm, hydramethylnon 400 ppm, and cyromazine 15,000 ppm. However, the number of baited used at the selected concentrations were not sufficient to totally eliminate the colonies. This result suggests that, in natural colonies of subterranean termites, different food resources and competition, in this case with the native species Heterotermes tenuis, could influence the success of the control programs. / Orientador: Ana Maria Costa Leonardo / Coorientador: Odair Correa Bueno / Banca: Maria Santina de Castro Morini / Banca: José Eduardo Marcondes de Almeida / Banca: Ana Eugenia de C. Campos Farinha / Banca: Alexandre de Sene Pinto / Doutor

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21157号 / 農博第2283号 / 新制||農||1059(附属図書館) / 学位論文||H30||N5131(農学部図書室) / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 吉村 剛, 教授 髙野 俊幸, 教授 梅澤 俊明 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

The effect of competing food sources on termite consumption of hexaflumuron bait and subsequent mortality was examined. Also, the effect of hexaflumuron on the termite gut fauna was evaluated to determine if hexaflumuron could kill termites via a secondary mode of action. Hexaflumuron consumption in no-choice and choice tests was evaluated at 2d and 5d. Total diet consumption was not different between the treatment groups. Hexaflumuron consumption was reduced by a factor of 3 in the presence of a competing control diet and reduced by a factor of 57 in the presence of an inulin diet. In the choice test, termites preferred inulin over hexaflumuron. Termite mortality after hexaflumuron consumption was quantified at 5d, 15d, 20d, 25d, and 35d in three treatment groups. Mean mortality for termites fed only hexaflumuron diet was significantly higher than termites fed only control diet. Mean mortality for termites given a choice was no different than mortality for termites fed only hexaflumuron or control diet. LT50s for termites fed control diet, hexaflumuron diet, or both diets in the choice test, were 24.4d, 18.7d, and 20.6d, respectively. The choice test LT50 did not differ from the LT50 of either no-choice test. Termites fed only hexaflumuron diet had an earlier LT50 than termites fed only control diet. The effect of hexaflumuron on gut fauna survival was evaluated at 5d and 15d. No significant differences were found in total numbers of protozoa in termites fed either hexaflumuron or control diet. Pyrsonympha was the only protozoa significantly reduced by hexaflumuron consumption. / Master of Science

Subterranean termites encounter numerous kinds of fungi during foraging and feeding activities. Nearly nine decades of research have exposed only a small fraction of the termitefungal interactions that exist in nature. The first portion of research presented here focused on how feeding behaviors of Reticulitermes virginicus (Banks) were affected by the fungus Trichoderma virens (Miller, Giddens & Foster) von Arx. Tests were performed with 'P' (GLT+) and 'Q'(GLT-) strains of T. virens. Both strains were applied to filter paper and wood disks cut from southern yellow pine and Sentricon® monitoring devices. The first bioassay assessed the termites' feeding responses to fungal extracts removed from liquid media on days 2 through 7, and again on day 15. Only the GLT+ extracts from days 6 and 7 inhibited termite feeding significantly from the controls (16% and 54% less area loss, respectively). Response to wood covered by live T. virens mycelia was tested in the second bioassay. No significant differences in termite consumption were seen between fungal strains, but both substantially reduced the area loss due to termite feeding of treated wood by an average of 35%. A vacuum impregnation system was used to inoculate wood disks with fungal homogenate in the third bioassay. The wood treated with either GLT+ or GLT- homogenates did not have significant differences in area loss due to termite feeding. Overall, these results reiterated the plasticity that exists with termitefungal relationships. The second research topic addressed the applicability of labrum-based identification techniques to Reticulitermes Holmgren in Texas. Soldier labral morphology of four species, R. flavipes (Kollar), R. hageni (Banks), R. tibialis Banks, and R. virginicus (Banks), was evaluated as a character to separate species. Length and width measurements of five soldier labra were taken from each of the eight collection sites. These results were then judged against molecular analysis of the mtDNA 16S rRNA gene. Findings showed that labral shape was an unreliable diagnostic characteristic when comparing all species. A combination of length and length-towidth ratio successfully segregated all four Reticulitermes species. Comparison of a morphology-based dendogram to the phylogenetic analysis revealed a shared pattern between phenotypic and genotypic variations.