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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

Dendroclimatological investigation of river red gum (Eucalyptus camaldulensis Dehnhardt) /

Argent, Robert Murray. January 1995 (has links)
Thesis (Ph. D.)--University of Melbourne, 1995. / Typescript. Includes bibliographical references (leaves [279]-287). Also available in electronic version via the World Wide.
2

Dendroclimatological investigation of river red gum (Eucalyptus camaldulensis Dehnhardt)

Argent, Robert Murray Unknown Date (has links) (PDF)
This thesis examines the growth ring structure of Eucalyptus camaldulensis Dehnhardt and investigates links between ring features and the climatic conditions under which growth took place. Samples of E. camaldulensis from the Barmah Forest (near the River Murray in northern Victoria) were used in the study. E. camaldulensis growth is linked to periodic flooding, and the Barmah Forest contains sites that are frequently flooded. Wood samples were obtained from sites subject to different average flooding frequencies. Trees used in the study grew out of natural regeneration in the 1920’s and 1930’s and from regeneration trials in the early 1960’s. Initial investigation of E. camaldulensis samples revealed ring-like features that were able to be traced on samples by eye. Microscopic investigation showed that there existed considerable variations in the properties of individual rings at different positions on the samples, and that the boundaries between rings were often indistinct.
3

Eucalypt regeneration on the Lower Murray floodplain, South Australia /

George, Amy Kathryn. January 2004 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2005? / "September 2004" Bibliography: p. 145-159.
4

Eucalypt regeneration on the Lower Murray floodplain, South Australia

George, Amy Kathryn. January 2004 (has links)
Thesis (Ph. D.)--University of Adelaide, 2004. / Title from PDF t.p. (viewed on Sept. 25, 2005). Includes bibliographical references (p. 145-159).
5

Densidade de amostragem de dados para análise da correlação espacial da produtividade do eucalipto em função de atributos do solo /

Corrêa, Adriany Rodrigues January 2018 (has links)
Orientador: Rafael Montanari / Resumo: Um dos fatores limitantes para o uso da agricultura de precisão é o número de amostras necessárias para representar espacialmente a distribuição do nutriente ou insumo aplicado de forma variada. Portanto objetivou-se com a presente pesquisa avaliar com base na análise geoestatística o número ideal de subamostras para compor uma composta que melhor determine as zonas específicas de manejo e ratificar a existência de um atributo (solo e/ou planta) que possa, espacialmente, funcionar como indicador de qualidade, isto é, caracterizar as zonas específicas de manejo, com o intuito de aumentar a produtividade do Eucalyptus camaldulensis com sete anos de idade. O estudo foi desenvolvido em 2015, na Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia de Ilha Solteira – UNESP, em Selvíria (MS, Brasil), latitude 20° 20’ 31” S, longitude 51° 24’ 12” W. Para tanto, foram analisadas as correlações lineares e espaciais entre atributos do eucalipto e de um LATOSSOLO VERMELHO Distrófico, os quais foram: circunferência à altura do peito (CAP), altura da árvore (ALT), o volume médio anual de madeira com a casca (VOL), densidade do solo (DS), resistência do solo à penetração (RP), teor umidade gravimétrica (UG), porosidade total (PT), potencial hidrogeniônico (pH), matéria orgânica (MO) e estoque de carbono (EC). Foi instalada uma malha geoestatística com 120 pontos, sendo constituída de seis transeções paralelas (sentido N-S), espaçadas em 14 m, com 20 pontos amostrais cada, espaç... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: One of the limiting factors for the use of precision agriculture is the number of samples needed to spatially represent the distribution of the nutrient or input applied in a varied way. Therefore, the objective of this research was to evaluate the ideal number of subsamples to compose a composite that better determines the specific areas of management and ratify the existence of an attribute (soil and / or plant) that can, spatially, to function as a quality indicator, that is, to characterize the specific areas of management, in order to increase the productivity of Eucalyptus camaldulensis at seven years of age. The study was conducted in 2015, at the UNESP - São Paulo State University, in Selvíria (MS, Brazil), latitude 20 ° 20 '31 "S, longitude 51 ° 24' 12" W. In order to do so, we analyzed the linear and spatial correlations between eucalyptus attributes and a Distrofic RED LATOSOLO, which were: circumference at breast height (CBH), height of the tree (HT), mean annual volume of wood with bark (VOL), soil bulk density (SB), soil penetration to resistance (PR), gravimetrical moisture contents (GM), total porosity (TP), hydrogenation potential (pH), organic matter (OM) and carbon stock content (CS). A geostatistical mesh was installed with 120 points, consisting of six parallel transects (N-S direction), spaced at 14 m, with 20 sample points each, spaced at 18 m, leaving a 10 m border. With three sample compositions, the sample composition of a single data (CA1), sample c... (Complete abstract click electronic access below) / Doutor
6

Densidade de amostragem de dados para análise da correlação espacial da produtividade do eucalipto em função de atributos do solo / Density for analysis of space correlation of eucalyptus productivity in the function of soil attributes

Corrêa, Adriany Rodrigues 02 March 2018 (has links)
Submitted by ADRIANY RODRIGUES CORRÊA (adriany@agronoma.eng.br) on 2018-04-27T21:15:18Z No. of bitstreams: 1 Adriany Rodrigues Corrêa.pdf: 2537499 bytes, checksum: 5f019ab13b90f73e544050f3efa14a28 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-05-02T13:59:01Z (GMT) No. of bitstreams: 1 correa_ar_dr_ilha.pdf: 2537499 bytes, checksum: 5f019ab13b90f73e544050f3efa14a28 (MD5) / Made available in DSpace on 2018-05-02T13:59:01Z (GMT). No. of bitstreams: 1 correa_ar_dr_ilha.pdf: 2537499 bytes, checksum: 5f019ab13b90f73e544050f3efa14a28 (MD5) Previous issue date: 2018-03-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Um dos fatores limitantes para o uso da agricultura de precisão é o número de amostras necessárias para representar espacialmente a distribuição do nutriente ou insumo aplicado de forma variada. Portanto objetivou-se com a presente pesquisa avaliar com base na análise geoestatística o número ideal de subamostras para compor uma composta que melhor determine as zonas específicas de manejo e ratificar a existência de um atributo (solo e/ou planta) que possa, espacialmente, funcionar como indicador de qualidade, isto é, caracterizar as zonas específicas de manejo, com o intuito de aumentar a produtividade do Eucalyptus camaldulensis com sete anos de idade. O estudo foi desenvolvido em 2015, na Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia de Ilha Solteira – UNESP, em Selvíria (MS, Brasil), latitude 20° 20’ 31” S, longitude 51° 24’ 12” W. Para tanto, foram analisadas as correlações lineares e espaciais entre atributos do eucalipto e de um LATOSSOLO VERMELHO Distrófico, os quais foram: circunferência à altura do peito (CAP), altura da árvore (ALT), o volume médio anual de madeira com a casca (VOL), densidade do solo (DS), resistência do solo à penetração (RP), teor umidade gravimétrica (UG), porosidade total (PT), potencial hidrogeniônico (pH), matéria orgânica (MO) e estoque de carbono (EC). Foi instalada uma malha geoestatística com 120 pontos, sendo constituída de seis transeções paralelas (sentido N-S), espaçadas em 14 m, com 20 pontos amostrais cada, espaçados em 18 m, deixando uma bordadura de 10 m. Com três composições amostrais, sendo a composição amostral de um único dado (CA1), composição amostral com média de cinco dados (CA5) e composição amostral com média de dez dados (CA10). O volume da madeira pôde ser estimado por meio da cokrigagem com a resistência a penetração do solo, ratificando assim a RP como um atributo potencial para atuar como indicador de qualidade visando o aumento da produtividade da madeira. Do ponto de vista espacial a Composição Amostral com Média de Dez Dados (CA10): apresentou-se como a mais satisfatória, sendo a única capaz de caracterizar a variabilidade dos atributos do Eucalyptus camaldulensis, possibilitando criar mapas relacionando-se com o solo, podendo determinar as zonas específicas de manejo. / One of the limiting factors for the use of precision agriculture is the number of samples needed to spatially represent the distribution of the nutrient or input applied in a varied way. Therefore, the objective of this research was to evaluate the ideal number of subsamples to compose a composite that better determines the specific areas of management and ratify the existence of an attribute (soil and / or plant) that can, spatially, to function as a quality indicator, that is, to characterize the specific areas of management, in order to increase the productivity of Eucalyptus camaldulensis at seven years of age. The study was conducted in 2015, at the UNESP - São Paulo State University, in Selvíria (MS, Brazil), latitude 20 ° 20 '31 "S, longitude 51 ° 24' 12" W. In order to do so, we analyzed the linear and spatial correlations between eucalyptus attributes and a Distrofic RED LATOSOLO, which were: circumference at breast height (CBH), height of the tree (HT), mean annual volume of wood with bark (VOL), soil bulk density (SB), soil penetration to resistance (PR), gravimetrical moisture contents (GM), total porosity (TP), hydrogenation potential (pH), organic matter (OM) and carbon stock content (CS). A geostatistical mesh was installed with 120 points, consisting of six parallel transects (N-S direction), spaced at 14 m, with 20 sample points each, spaced at 18 m, leaving a 10 m border. With three sample compositions, the sample composition of a single data (CA1), sample composition with a mean of five data (CA5) and sample composition with a mean of ten data (CA10). The volume of the wood could be estimated by means of cokriging with resistance to soil penetration, thus confirming the PR as a potential attribute to act as a quality indicator aiming at increasing wood productivity. From the spatial point of view, the Composition Sampling with Average of ten data (CA10): presented the most satisfactory, being the only one able to characterize the variability of the attributes of Eucalyptus camaldulensis, making it possible to create maps relating to the soil, specific management areas.
7

Bioacumulación de elementos traza en especies estabilizadoras (Acacia saligna (Labill) H. Wendl y Eucalyptus camaldulensis (Dehnh) en tranques de relaves

Medina Quintanilla, Tomás January 2010 (has links)
Memoria para optar al Título Profesional de Ingeniero Forestal / Un estudio comparativo de concentraciones de algunos elementos traza fue llevado a cabo para dos especies forestales estabilizadoras, Acacia saligna y Eucalyptus camaldulensis, ubicadas sobre un complejo de tranques de relaves. Los tejidos vegetales y los sustratos fueron muestreados tanto en sitios cubiertos por los relaves como sitios aledaños (grupo control) de manera de evaluar las concentraciones y distribución de elementos traza en los tejidos de las plantas (hojas, ramas, frutos, tallos y raíces). Los sustratos de relave fueron muestreados a dos profundidades, determinándose, en cada uno de ellos, las fracciones biodisponibles y totales de los elementos Cu, Mn, Fe y Zn. En términos generales, se presentaron diferencias significativas entre los sitios muestreados, acumulándose una mayor cantidad de elementos traza en los individuos ubicados en el grupo relave tanto para tejidos vegetales como para los sustratos. En el caso de Acacia saligna el elemento que presentó la mayor acumulación fue el Fe, principalmente ubicado en las raíces con un comportamiento similar tanto en el grupo control como en el relave. Las concentraciones de Cu fueron más altas en las raíces de los individuos ubicados en el grupo relave. El Zn presentó mayores concentraciones en el grupo relave pero se distribuyó homogéneamente entre los tejidos. En general, el comportamiento de los elementos trazas en Eucalyptus camaldulensis fue similar al presentado en Acacia saligna salvo las concentraciones de Mo las cuales fueron menores.
8

Ecology of the Fergusonina fly and Fergusobia nematode gall association in South Australia.

Head, Elise January 2008 (has links)
Attempts were made to grow Fergusobia nematodes in a dual aseptic culture with Eucalyptus camaldulensis. Callus tissue was grown from E. camaldulensis stem pieces in aseptic conditions. Calli were prone to deterioration after 14 days unless transferred to fresh growth medium. Lower levels of solutes (25% Murashige and Skoog salts, 25% plant vitamins and 0.5% sucrose) were more successful than published concentrations. Fergusobia J2 nematodes were surface sterilised with either Hibitane or washed with water to prepare them for inoculation of callus (Hay, 1994). Fergusobia subsequently recovered from plates of callus were all dead, which raised questions of how the nematodes are suited to Murashige and Skoog salt solutions. The survival of Fergusobia in aqueous solutions was then observed. It has been assumed that Fergusobia live about 2 days after dissection. Amphimictic nematodes from E. camaldulensis axial bud galls were used for a survival study. Nematodes lived for as long as 12 days in fresh tap water and 11 days in 1% M.S. solution. They were more active in tap water than in 1% M.S. solution. Nematodes in a dish together with dissected gall material died within 2 days. Nematodes in a separate dish with fresh tap water and clean gall fibres were observed to gather around the fibres. Observations of Fergusobia could be made within fresh solutions providing deteriorating gall tissues were removed from the dish. Gall production was attempted on E. camaldulensis grown in the glasshouse. These tree saplings were pruned to encourage new growth and periodically treated for infestations of scale insects leading to growth of sooty mould. Two forms of cage construction were used: (1) 1 m ³ screened cages and (2) acetate sleeves as used by Goolsby et al., 2000. Within the 1 m ³ cages containing flies, the growing points on saplings were blackened, possibly due to over-exploitation by ovipositing flies. One growing point caged in an acetate sleeve showed oviposition scars but did not produce a mature gall. Production of galls in the glasshouse was hindered by a lack in coincidence of flies emerging from mature galls and the flush of new growth following pruning. The production of galls within the glasshouse was not achieved. The phenology of E. camaldulensis, a host for the Fergusonina/Fergusobia mutualism, and gall ecology were observed in a two-year, non-destructive, field study in the Urrbrae Wetlands, Adelaide, South Australia. Tree growth and gall development was observed in the lower regions (0 – 2 m) of young trees. Three bud forms, terminal leaf bud, axial leaf bud and flower bud galls were monitored on the trees. The densities of galls were highly seasonal. Greatest density of growing points, axial leaf bud and flower bud galls occurred mostly during mid-winter to spring, whereas that of terminal leaf bud galls occurred during mid-spring to summer. Galling of flower buds did not appear to influence flowering and more flower buds and flowers occurred in the second year of the study as the trees matured. Trees mostly had medium (30-70%) levels of leaf damage, but there were seasonal trends in damage levels. Low scores for leaf damage were associated with increases in flower bud and flower production. Leaf damage, including sooty mould, appeared to increase during the cooler winter months. There were no significant seasonal relationships between levels of leaf damage and either growing point density or the occurrence of galls. When trees were compared with each other, those with lower leaf damage were more likely to have more growing points. The appearance of the canopy and the likelihood of a tree to have galls varied greatly between the trees. One tree was particularly susceptible to leaf attack, rarely had new leaves and produced no mature galls during the study. The colouring of leaves varied between trees, which indicates possible genetic variations causing some trees to be more likely hosts for Fergusonina/Fergusobia. Both new vegetative growth and terminal leaf bud galls were concentrated on the northern and eastern quadrants. Axial leaf bud and flower bud galls occurred more on the western or southern quadrants where they were possibly more protected from sun exposure on the northern or eastern quadrants. Axial galls on the northern side of one tree became reddened while those in the southern and western quadrants remained green. Reddening of axial galls may increase their likelihood of parasitism and predation by birds. Each of the three gall forms occurred within certain positions in the canopy. The tree host resource is partitioned effectively, with the three gall forms occurring on three different host structures. Additionally, the two vegetative forms terminal leaf bud and axial leaf bud galls occur on different shoot regions and in different seasons. The numbers of the galls is probably also affected by biotic and climatic influences. Parasitism, plant canopy shading, nutrient levels and host genetics are possible influences. Assuming an interval of 4 weeks between oviposition and first observation within the current study, terminal leaf bud galls had an average longevity of 11 weeks and axial leaf bud galls an average longevity of 14 weeks. Flower bud galls had longevities of 14 to 27 weeks from oviposition to senescence, assuming an interval of 6 weeks between oviposition and first observation within the current study. Flowers and flower buds occur irregularly within the eucalypts so it would be advantageous for flies and nematodes developing within flower bud galls to have extended or variable longevities to allow fly emergences to coincide with new flower buds. Not all of the galls recorded matured to produce adult flies. Nearly half of the terminal leaf bud galls initiated were aborted, recorded as absent, parasitised or eaten (45% of initiated galls). Of the three gall forms, they were the most prone to obvious parasitism and as many as 12 hymenopteran species have been reared from terminal leaf bud galls on E. camaldulensis (Taylor et al., 1996). These galls obviously provide a resource for many species within multiple trophic levels. Fourteen percent of axial leaf bud galls were absent or eaten and birds were seen breaking off and feeding on the galls. More than half (55%) of the initiated flower bud galls disappeared during the period of observation, possibly due to the foraging of birds. Destructive sampling and rearing out of parasitoids from both axial leaf bud and flower bud gall forms is needed to establish what species exist within them. Terminal leaf bud galls ranged from 7.5 to 30.1 mm in diameter and 10.0 to 43.6 mm in length. Flower bud gall size varied, with the largest being 15.0 mm by 22.3 mm. Axial leaf bud galls, ranged from 2.6 to 13.0 mm in diameter and length ranged from 2.3 to 10.5 mm. The larger axial leaf bud galls were nodular and appeared to have multiple locules. Destructive sampling and rearing out of flies is needed to establish the relationship between size and numbers of flies emerging. Terminal leaf bud galls increased in size, including many locules and exit holes per gall. Axial leaf bud galls were much smaller than the terminal leaf bud galls and 99% had only one to three exit holes. The rounded shape and presence of few locules within the axial leaf bud galls indicate that this form is limited to a shape and size producing few flies. The observation of greater size of terminal leaf bud galls suggests that these galls may have multiple foundresses. Twelve of the 13 flower bud galls with exit holes had either one or two holes. In flower bud galls on E. camaldulensis. the operculum remains sealed and the characteristic Fergusonina “window” appears at the side of the flower bud before fly emergence through a single hole. Destructive sampling is also necessary to determine parasitism of each of the gall forms. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1331016 / Thesis (M.Sc.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008
9

Eucalypt regeneration on the Lower Murray floodplain, South Australia.

George, Amy Kathryn January 2004 (has links)
Vegetation along the River Murray floodplains has been shown to be in a severe state of decline. This decline is amplified by the impositions of river regulation. In South Australia, where vegetation losses have been great, regeneration is limited and may result in not only individual tree losses but also widespread population decline. This study aimed to examine the relationship between river flows and the regeneration process in populations of Eucalyptus camaldulensis and Eucalyptus largiflorens. The current structure of the populations was examined to determine if a viable number of varying age-classed trees were present. Tree surveys conducted at Banrock Station determined that while densities were low for both species, E. camaldulensis had a more sustainable population structure than E. largiflorens. Growth stages for both species illustrated highly clumped distribution, which is believed to correspond with river flooding magnitudes and frequencies. To address the potential link between tree distribution and flooding within the River Murray, a hydrological analysis was conducted for Banrock Station using river flows at the South Australian border from 1900 to 2003. The amount of time growth stages for each species were inundated was found to be greatly reduced under regulated flows compared to natural flows. This has resulted in shifted localized regeneration patterns corresponding with E. camaldulensis' greater demand for inundation than E. largiflorens. Moderate magnitude flows have been most impacted by regulation, and consequently these are the very flows needed for floodplain tree population maintenance. Flowering and seed fall for E. camaldulensis and E. largiflorens were monitored at Banrock Station for 22 months to identify losses in reproductive potential resulting from tree decline. While seed viability was not affected by vigour, trees with visually reduced vigour were found to produce less fruit and had reduced seed fall, as well as a reduced rate of fruit development. Dendrochronological techniques were applied to floodplain trees. Age and size relationships could be established, implying that such techniques can be applied in South Australia to high quality sites. Growth responses within cohorts were similar and easily matched between individuals illustrating cyclic, but not necessarily seasonal correlations. This work verified the preferential selection of younger trees for dendroecological studies, and identified a relationship between on moderate flows and measurable girth expansion in both floodplain tree species. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2004.
10

Ecology of the Fergusonina fly and Fergusobia nematode gall association in South Australia.

Head, Elise January 2008 (has links)
Attempts were made to grow Fergusobia nematodes in a dual aseptic culture with Eucalyptus camaldulensis. Callus tissue was grown from E. camaldulensis stem pieces in aseptic conditions. Calli were prone to deterioration after 14 days unless transferred to fresh growth medium. Lower levels of solutes (25% Murashige and Skoog salts, 25% plant vitamins and 0.5% sucrose) were more successful than published concentrations. Fergusobia J2 nematodes were surface sterilised with either Hibitane or washed with water to prepare them for inoculation of callus (Hay, 1994). Fergusobia subsequently recovered from plates of callus were all dead, which raised questions of how the nematodes are suited to Murashige and Skoog salt solutions. The survival of Fergusobia in aqueous solutions was then observed. It has been assumed that Fergusobia live about 2 days after dissection. Amphimictic nematodes from E. camaldulensis axial bud galls were used for a survival study. Nematodes lived for as long as 12 days in fresh tap water and 11 days in 1% M.S. solution. They were more active in tap water than in 1% M.S. solution. Nematodes in a dish together with dissected gall material died within 2 days. Nematodes in a separate dish with fresh tap water and clean gall fibres were observed to gather around the fibres. Observations of Fergusobia could be made within fresh solutions providing deteriorating gall tissues were removed from the dish. Gall production was attempted on E. camaldulensis grown in the glasshouse. These tree saplings were pruned to encourage new growth and periodically treated for infestations of scale insects leading to growth of sooty mould. Two forms of cage construction were used: (1) 1 m ³ screened cages and (2) acetate sleeves as used by Goolsby et al., 2000. Within the 1 m ³ cages containing flies, the growing points on saplings were blackened, possibly due to over-exploitation by ovipositing flies. One growing point caged in an acetate sleeve showed oviposition scars but did not produce a mature gall. Production of galls in the glasshouse was hindered by a lack in coincidence of flies emerging from mature galls and the flush of new growth following pruning. The production of galls within the glasshouse was not achieved. The phenology of E. camaldulensis, a host for the Fergusonina/Fergusobia mutualism, and gall ecology were observed in a two-year, non-destructive, field study in the Urrbrae Wetlands, Adelaide, South Australia. Tree growth and gall development was observed in the lower regions (0 – 2 m) of young trees. Three bud forms, terminal leaf bud, axial leaf bud and flower bud galls were monitored on the trees. The densities of galls were highly seasonal. Greatest density of growing points, axial leaf bud and flower bud galls occurred mostly during mid-winter to spring, whereas that of terminal leaf bud galls occurred during mid-spring to summer. Galling of flower buds did not appear to influence flowering and more flower buds and flowers occurred in the second year of the study as the trees matured. Trees mostly had medium (30-70%) levels of leaf damage, but there were seasonal trends in damage levels. Low scores for leaf damage were associated with increases in flower bud and flower production. Leaf damage, including sooty mould, appeared to increase during the cooler winter months. There were no significant seasonal relationships between levels of leaf damage and either growing point density or the occurrence of galls. When trees were compared with each other, those with lower leaf damage were more likely to have more growing points. The appearance of the canopy and the likelihood of a tree to have galls varied greatly between the trees. One tree was particularly susceptible to leaf attack, rarely had new leaves and produced no mature galls during the study. The colouring of leaves varied between trees, which indicates possible genetic variations causing some trees to be more likely hosts for Fergusonina/Fergusobia. Both new vegetative growth and terminal leaf bud galls were concentrated on the northern and eastern quadrants. Axial leaf bud and flower bud galls occurred more on the western or southern quadrants where they were possibly more protected from sun exposure on the northern or eastern quadrants. Axial galls on the northern side of one tree became reddened while those in the southern and western quadrants remained green. Reddening of axial galls may increase their likelihood of parasitism and predation by birds. Each of the three gall forms occurred within certain positions in the canopy. The tree host resource is partitioned effectively, with the three gall forms occurring on three different host structures. Additionally, the two vegetative forms terminal leaf bud and axial leaf bud galls occur on different shoot regions and in different seasons. The numbers of the galls is probably also affected by biotic and climatic influences. Parasitism, plant canopy shading, nutrient levels and host genetics are possible influences. Assuming an interval of 4 weeks between oviposition and first observation within the current study, terminal leaf bud galls had an average longevity of 11 weeks and axial leaf bud galls an average longevity of 14 weeks. Flower bud galls had longevities of 14 to 27 weeks from oviposition to senescence, assuming an interval of 6 weeks between oviposition and first observation within the current study. Flowers and flower buds occur irregularly within the eucalypts so it would be advantageous for flies and nematodes developing within flower bud galls to have extended or variable longevities to allow fly emergences to coincide with new flower buds. Not all of the galls recorded matured to produce adult flies. Nearly half of the terminal leaf bud galls initiated were aborted, recorded as absent, parasitised or eaten (45% of initiated galls). Of the three gall forms, they were the most prone to obvious parasitism and as many as 12 hymenopteran species have been reared from terminal leaf bud galls on E. camaldulensis (Taylor et al., 1996). These galls obviously provide a resource for many species within multiple trophic levels. Fourteen percent of axial leaf bud galls were absent or eaten and birds were seen breaking off and feeding on the galls. More than half (55%) of the initiated flower bud galls disappeared during the period of observation, possibly due to the foraging of birds. Destructive sampling and rearing out of parasitoids from both axial leaf bud and flower bud gall forms is needed to establish what species exist within them. Terminal leaf bud galls ranged from 7.5 to 30.1 mm in diameter and 10.0 to 43.6 mm in length. Flower bud gall size varied, with the largest being 15.0 mm by 22.3 mm. Axial leaf bud galls, ranged from 2.6 to 13.0 mm in diameter and length ranged from 2.3 to 10.5 mm. The larger axial leaf bud galls were nodular and appeared to have multiple locules. Destructive sampling and rearing out of flies is needed to establish the relationship between size and numbers of flies emerging. Terminal leaf bud galls increased in size, including many locules and exit holes per gall. Axial leaf bud galls were much smaller than the terminal leaf bud galls and 99% had only one to three exit holes. The rounded shape and presence of few locules within the axial leaf bud galls indicate that this form is limited to a shape and size producing few flies. The observation of greater size of terminal leaf bud galls suggests that these galls may have multiple foundresses. Twelve of the 13 flower bud galls with exit holes had either one or two holes. In flower bud galls on E. camaldulensis. the operculum remains sealed and the characteristic Fergusonina “window” appears at the side of the flower bud before fly emergence through a single hole. Destructive sampling is also necessary to determine parasitism of each of the gall forms. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1331016 / Thesis (M.Sc.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008

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