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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.
21

Field Survey of Native and Non-Native Subterranean Termites in Southeastern United States Forests

Blount, Nathan Allen 15 December 2012 (has links)
Subterranean termites are ecologically and economically important insects that play major roles in organic matter decomposition and nutrient cycling. The Formosan subterranean termite, Coptotermes formosanus Shiraki, is an invasive species known to cause significant damage in urban areas through aggressive consumption of wooden structures and infestations of living trees. Little is known about the presence and impact of C. formosanus in forested ecosystems of the southeastern U.S. as the majority of studies have taken place in urban settings. This study investigates the prevalence of C. formosanus in localized forests, as well as the utilization of living trees by C. formosanus and native subterranean termite species (Reticulitermes spp.). Recently harvested timber stumps were inspected for subterranean termite presence on sites throughout Mississippi and Louisiana. Alate light traps were utilized for further C. formosanus detection. Three sites yielded C. formosanus alate catches, while 7,413 stump inspections produced 406 Reticulitermes spp. infestations.
22

Termite control for homeowners

Baker, Paul B. 03 1900 (has links)
9 pp. / Termites are considered Arizona's number one urban pest. All termites can be placed into 3 broad categories based on their habitat: damp-wood, dry-wood and subterranean. In Arizona, damp-wood and dry wood termites are not major wide spread problems but can be under selected conditions. Subterranean termites on the other hand are considered one of our major urban pests. Detection of the presence of termites in many cases can be difficult to do. A discussion of construction practices is presented to keep termites from invading your home. Control technologies such as a pre and post-treatment using a termiticide, physical barriers and baiting systems are presented.
23

Padrões morfológico-evolutivos em espécies subterrâneas de Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trichomycteridae) / Morphological-evolutionary patterns in subterranean species of Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trichomycteridae)

Rizzato, Pedro Pereira 05 June 2014 (has links)
Um dos principais objetivos da Biologia Subterrânea é identificar e entender as modificações morfológicas apresentadas pelos organismos subterrâneos que podem ser relacionadas a seu modo de vida. No presente trabalho, realizamos essa investigação utilizando como modelo as espécies subterrâneas de Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trihomycteridae). Atualmente são conhecidas sete espécies subterrâneas do gênero, as quais se distribuem em regiões geográficas muito próximas entre si, as áreas cársticas de São Domingos e de Mambaí e Posse, no nordeste do estado de Goiás. Analisamos caracteres externos (tamanho e alonga-mento corporal, nadadeiras pares e pigmentação) e sensoriais (olhos, barbilhões, sistema láte-rosensorial e encéfalo), e identificamos tendências de modificação em todos eles. As espécies subterrâneas de Ituglanis tendem a apresentar: alongamento do corpo e, nas espécies que tran-sitam ou ocupam espaços confinados, redução do tamanho corporal; nadadeiras peitorais mais longas e com mais raios, e as pélvicas reduzidas; pigmentação reduzida, os cromatóforos me-nos abundantes e com formas irregulares; olhos menores, deformados, assimétricos e encober-tos por pele; barbilhões bem desenvolvidos, os maxilares mais longos; sistema láterosensorial de canais fragmentado e reduzido, com grande variabilidade e assimetria; e o encéfalo com lobos vagais e faciais desenvolvidos, lobos ópticos reduzidos e aumento do tamanho do cere-belo, da bexiga natatória e dos canais semicirculares do ouvido interno. Muitas dessas caracte-rísticas já haviam sido observadas em espécies subterrâneas de outros grupos de peixes, suge-rindo que elas de fato estejam relacionadas a esse modo de vida. Nem todas as espécies sub-terrâneas de Ituglanis apresentam todas as características em um mesmo grau, de forma que é possível dividi-las entre as menos troglomórficas, Ituglanis sp. 1 e I. mambai, as intermediá-rias, Ituglanis sp. 2 e I. bambui, e as mais troglomórficas, I. passensis, I. ramiroi e I. epikars-ticus. A grande variabilidade tanto intra- quanto interespecífica sugere que essas característi-cas evoluem em mosaico, corroborando hipóteses anteriores de colonização independente do ambiente subterrâneo por cada uma das espécies. As modificações identificadas podem ser divididas em progressivas e regressivas, e discutimos os mecanismos evolutivos que explicam seu surgimento nas espécies subterrâneas. A evolução de características que conferem vanta- gem evolutiva é explicada por mecanismos de seleção natural direta, enquanto que os caracte-res regressivos que não apresentam vantagem ou desvantagem óbvia se encaixam em cenários de evolução neutra. Algumas das características das espécies subterrâneas são típicas de indi-víduos em estágios iniciais de desenvolvimento, o que sugere que a heterocronia pode ter um papel importante na evolução do troglomorfismo. Além disso, a linhagem a que pertencem as espécies subterrâneas apresenta características consideradas preaptativas para o modo de vida subterrâneo, o que favoreceria o desenvolvimento desse modo de vida repetidas vezes na fa-mília Trichomycteridae e, mais especificamente, no gênero Ituglanis. / One of the main objectives of Subterranean Biology is to identify and understand the morpho-logical modifications exhibited by subterranean organisms which can be related to their hypogean life habit. In the present work, we performed this investigation using as model the subterranean species of Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trihomycteridae). Nowadays, seven subterranean species of the genus are recognized, distributed in close geo-graphic regions, the São Domingos karstic area and the Mambaí and Posse karstic area, both on northeastern Goias state, Brazil. We analyzed external (body size and elongation, paired fins and pigmentation) and sensorial characters (eyes, barbels, laterosensory system and brain), and identified tendencies of modification in all of them. Subterranean species of Ituglanis tend to shown: body elongation, and those species occupying confined spaces, body-size reduction; longer pectoral fins, with increased number of rays, and pelvic fins reduced; reduced pigmentation, the cromatophores less numerous and with irregular forms; smaller, deformed and asymmetric eyes, covered by skin; well developed barbels, the maxillary long-er; the canals of the laterosensory system fragmented and reduced, with variability and asymmetry; and the brain with well developed vagal and facial lobes, reduced optic lobes and increased cerebellum, swim bladder and semicircular canals of the inner ear. Many of these characters were already reported for subterranean fishes of other groups, suggesting a rela-tionship with this life habit. The subterranean species of Ituglanis does not exhibit all the characters on the same degree, in such a way that it is possible to classify them as the less troglomorphic, Ituglanis sp. 1 and I. mambai, the intermediary, Ituglanis sp. 2 and I. mambai, and the most troglomorphic, I. passensis, I. ramiroi and I. epikarsticus. The large inter- and intraspecific variability observed suggests a mosaic of evolution for these characters, corrobo-rating previous hypothesis of independent colonization of the subterranean environment in each species. The modifications identified can be divided in progressive and regressive, and we discuss the evolutionary mechanisms that explain their origin. The evolution of characters that can be evolutively advantageous is explained by mechanisms of direct natural selection, whilst regressive characters that do not provide any obvious advantage os disadvantage fit to scenarios of neutral evolution. Some of the characters observed in the subterranean species are typical of individuals in early stages of development, suggesting that heterocrony can play an important role in the evolution of troglomorphism. Furthermore, the lineage to which the subterranean species belong exhibit some characters considered preadaptative for the subter-ranean life habit, favouring its development repeatedly in the family Trichomycteridae and, more specifically, in the genus Ituglanis.
24

The influence of defoliation on the growth of subterranean clover (Trifolium subterraneum L) : thesis submitted for the degree of Master of Agricultural Science

Davidson, J. L. (James Logie) January 1956 (has links) (PDF)
Typewritten copy Includes bibliographical references
25

Effects of soil compaction on growth and P uptake by Trifolium subterraneum colonised by VAM fungi / by Habib Nadian Ghomsheh.

Ghomsheh, Habib Nadian January 1997 (has links)
Bibliography: leaves 146-170. / xix, 170 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--Dept. of Soil and Water, Waite Agricultural Research Institute, University of Adelaide, 1994
26

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.
27

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.
28

Toxicity of boron compounds in the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae)

Gentz, Margaret C January 2007 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2007. / Includes bibliographical references (leaves 41-45). / v, 45 leaves, bound 29 cm
29

The effects of temperature on growth and nitrogen fixation in Trifolium subterraneum / by Robin Paul Geoffrey Gates

Gates, Robin Paul Geoffrey January 1984 (has links)
Bibliography: last 24 unnumbered leaves / 161, [32] leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1985
30

Functional morphology and evolution of marsupial moles (Marsupialia: Notoryctemorphia)

Warburton, Natalie Marina January 2003 (has links)
Marsupial moles (genus Notoryctes) are the most highly specialised burrowing marsupials. The specialisations of the appendicular musculo-skeletal system of the marsupial moles are extensive and widespread; the major alterations are concentrated in, but not restricted to, the forelimb. Many of the derived features of the muscular system appear to be adaptations for improving the mechanical advantage of the limbs for burrowing. A number of the specialisations of the muscular system of the marsupial moles are convergent with those previously documented in other fossorial mammals, including golden moles, rodents and armadillos. There are, however, a number of unique specialisations of the musculo-skeletal system of Notoryctes. The functional morphology of the locomotor apparatus of marsupial moles is interpreted on the basis of the descriptions of the anatomy of the skeletal and muscular systems. The burrowing technique of the marsupial moles is a modified form of the parasagittal digging method that is used by other fossorial mammals, such as golden moles, armadillos and some rodents including pocket gophers. Differences in the functional morphology of the hindlimb between marsupial moles and other fossorial mammals are a reflection of the fact that marsupial moles do not construct permanent open burrow systems, but instead constantly dig through loose soil, backfilling as they progress. The functional morphology of the tail is uniquely specialised in the marsupial moles to function as the fifth limb during the pentapedal burrowing locomotion of marsupial moles. The remains of Miocene fossil marsupial mole, while clearly pleisiomorphic with respect to the appendicular skeletal morphology of modern notoryctids, demonstrate a high degree of specialisation for digging. It is hypothesised that the Miocene marsupial mole was already substantially specialised for a fossorial lifestyle, and thus pre-adapted for a subterranean lifestyle developed in correlation with the desertification of the Australian continent. Phylogenetic affinities of marsupial moles within the Marsupialia have long been enigmatic. While specialisation of the musculo-skeletal system have been so widespread as to obscure almost any phylogenetically relevant patterns, there is some evidence to support an association between notoryctids and peramelid bandicoots. Interspecific differences between the two species of marsupial moles, Notoryctes typhlops and N. caurinus, are minor but do support the separation of the two species.

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