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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.
61

The ecology of stem boring wainscot moths in Phragmites australis reedbeds

Clements, Deborah A. V. January 2000 (has links)
No description available.
62

Factors in population regulation by insect parasitoids

Lynch, Liam David January 1998 (has links)
No description available.
63

The effect of the haemolymph protein apolipophorin-III on the antimicrobial responses of the insect Galleria mellonella to the bacterium, Bacillus subtilis /

Zakarian, Robert J. January 2002 (has links)
Apolipophorin-III (apoLp-III) is known to influence the haemocyte-mediated induction of antimicrobial peptides in Galleria mellonella and yeast phagocytosis, bind to Gram-negative and Gram positive bacteria and limit the activation of the haemocytes and the prophenoloxidase system by bacterial surface antigens. The effects of apoLp-III on haemocyte adhesion to glass slides and to bacteria were herein examined. ApoLp-III bound to haemocytes limiting the adhesion of both granular cells and plasmatocytes to glass and the contact of the plasmatocytes with Bacillus subtilis. The percentage of granular cells with bacteria was increased by the protein. However, the total number of bacteria adhering to haemocytes in vitro declined in the presence of apoLp-III. Bacterial removal from the haemolymph in vivo by the haemocytes was slowed by the protein. / The adhesion of both the granular cells and plasmatocytes to slides was decreased by inhibiting protein tyrosine kinase and increased by inhibiting protein kinase A (PKA) and protein kinase C (PKC) activity. The latter was confirmed with haemocytes inhibited by the general PKC inhibitor H-7 using phorbol-3-myfstate (PMA) which, by activating PKC, diminished the adhesion of both haemocyte types. Limiting the formation of PKC activation by diacylglycerides which is produced by phosholipase C (PLC), using PLC inhibitor also increased haemocyte attachment. Although binding of B. subtilis to haemocytes decreased PKC activity, the effect of apoLp-III on PKC was inconclusive.
64

The Migration Systems of Helicoverpa punctigera (Wallengren) and Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in Australia

Rochester, Wayne Allan Unknown Date (has links)
The contemporary view of insect migration is one of a behaviourally distinct form of movement that is an adaptation to temporary habitats. Migratory insects are characterised by a syndrome of behavioural and physiological traits that promote migration. The migration syndromes of particular species are variations on the general syndrome, and depend on both selective pressures from the environment and the evolutionary response that is supported by the genetics of the syndrome traits. The pattern and role of migration in a particular population are determined by the interaction between the environment and the species’ migration syndrome. Complete understanding of migration in a population therefore requires a combined consideration of the population’s environment, migration syndrome and genetics. A recently developed conceptual model of a generalised insect migration system facilitates such a holistic treatment of insect migration. The model is built around four components: the migration arena (the environment); the population trajectory (the changing population demography); the migration syndrome (the traits that implement migration and determine the fitness of migrants); and the genetic complex underlying the migration syndrome. Specific variants of the model can be derived for particular species and locations. The migratory moth species Helicoverpa punctigera (Wallengren) and Helicov-erpa armigera (H¨ ubner) are widely distributed in Australia, and occur in both crop-ping and non-cropping areas. The habitats occupied by the species are often tem-porary and geographically separated. Moths colonise new habitats by long-distance migration. Both species are abundant in the periphery of the continent during summer. In winter, H. punctigera is almost exclusively confined to the far inland, whereas H. armigera mostly remains near the coast. This thesis describes the development and application of conceptual models of the migration systems of H. punctigera and H. armigera in Australia. The model for H. punctigera was used to formulate and test hypotheses on the species’ population trajectory. That for H. armigera was used to determine the effects of differences between the migration syndromes of the two species on the trajectory. The models incorporated data from empirical models and simulation models developed for selected parts of the migration systems. Bioclimatic models estimated the portion of the continent that is climatically favourable for colonisation by each species in each season. A second type of bioclimatic model estimated the effect of year-to-year variation in habitat quality on the distribution of H. punctigera breeding in the inland. Finally, a simulation model of moth migration estimated the frequency with which wind patterns support various migration pathways. For H. punctigera the portion of the continent predicted to be climatically favourable for breeding tended to cycle between the inland and the periphery, al-though, contrary to observations, central Queensland was predicted to be favourable year-round. In the far inland the winter breeding period was predicted to be sub-stantially shorter in Western Australia than in south-western Queensland. For H. armigera the potential distribution tended to expand and contract around a core area in central Queensland. The probability of H. punctigera breeding at a given site in the far inland during winter was positively correlated with the increase in vegetation greenness at the site between April and July. It was also related to soil and climate variables. Although breeding was predicted to occur more often in some areas than in others, the esti-mated distribution of breeding varied greatly from year to year, and breeding was predicted at any given site in only a minority of years. Validation analyses indicated that the migration model was sufficiently accu-rate for use in characterising the migration system. However, the limited vertical structure present in the available weather data (e.g. representing low-level jets) will prevent the model from confidently forecasting particular migration events. Complete annual cycles of the population trajectory of H. punctigera could be constructed within the limits of the migration arena and the known migration syn-drome. In eastern Australia the cycle included return migration from the eastern cropping areas to the far inland during autumn, as has previously been proposed in the literature. In Western Australia two trajectories were possible—one including spring diapause and a late summer generation in the south-west, and one including a summer generation in the far south-west. Additional trajectories were possible when pupae in spring diapause were assumed to emerge later than has been observed, or when summer quiescence was assumed to be more frequent than would be expected from our currently limited knowledge of its induction. These assumptions enabled H. punctigera to persist throughout the year in the far inland of eastern Australia, but not in that of the west. The conceptual models enabled certain hypotheses on the population trajectories to be tested with existing field and biological data. For other hypotheses they identified data that would enable testing. For a decision on which, if any, of the above H. punctigera trajectories operate in nature, we need more information on the frequency and duration of spring diapause and summer quiescence, plus additional data on breeding activity in parts of Western Australia.
65

Ecological niche responses of small mammals to gypsy moth disturbance /

Tomblin, David Christian. January 1994 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 154-164). Also available via the Internet.
66

Effect of the axenic nematode Steinernema carpocapsae on the immune responses of two Lepidopteran larvae Galleria mellonella (F. Pyralidae) and Malacosoma disstria (F. Lasiocampidae)

Walter, Ndonkeu Tita. January 1900 (has links)
Thesis (Ph.D.). / Written for the Dept. of Natural Resource Sciences. Title from title page of PDF (viewed 2009/06/11). Includes bibliographical references.
67

Some biochemical aspects of growth and development of the greater wax moth, Galleria mellonella (L.).

Silhacek, Donald LeRoy, January 1967 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
68

Potential lethal and sublethal effects of gypsy moth biological treatments on non-target Lepidopterans in two Appalachian forests

Rastall, Kenneth Edward. January 1999 (has links)
Thesis (Ph. D.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains x, 149 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 138-142).
69

Effects of nitrogen and water on growth, photosynthesis, and leaf properties of deciduous tree species with consequences for gypsy moth herbivory

Myers, Teri S. January 2000 (has links)
Thesis (Ph. D.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains ix, 118 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.
70

The larval parasites of the Oriental peach moth (L̲a̲s̲p̲e̲y̲r̲e̲s̲i̲a̲ m̲o̲l̲e̲s̲t̲a̲ Busck) with special reference to the biology of M̲a̲c̲r̲o̲c̲e̲n̲t̲r̲u̲s̲ a̲n̲c̲y̲l̲i̲v̲o̲r̲a̲ Rohwer,

Stearns, Louis Agassiz, January 1928 (has links)
Thesis (Ph. D.)--Ohio state University, 1928. / Autobiography. Bulletin 460 of the New Jersey agricultural experiment station (23 cm) with 2 prelim. leaves (t.-p. and preface) and 1 leaf containing autobiography added. Bibliography: p. 24.

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