Dissertations / Theses on the topic 'Australian insect'
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1
Peeters, Paula J. (Paula Jane) 1969. "Relationships between leaf traits and herbivorous insect assemblages in a temperate Australian forest." Monash University, Dept. of Biological Sciences, 2001. http://arrow.monash.edu.au/hdl/1959.1/8792.
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Chitra, Eric, and n/a. "Bionomics of Culicoides molestus (Diptera: Ceratopogonidae): a pest biting midge in Gold Coast canal estates." Griffith University. School of Environmental and Applied Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20041119.101151.
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Culicoides molestus (Skuse) is the major species of biting midge that plagues human comfort in the estuarine Gold Coast region of southeast Queensland. Local authorities have initiated a search for an effective, non-chemical means of control, that would minimize human-midge interaction. The effectiveness of a program to control an organism, such as a biting midge, is dependent upon knowledge of the biology of the particular organism of interest. This project revolved examines the lifecycle of C. molestus in detail. It addresses questions regarding the location, seasonal distribution, and dispersal of its juvenile stages in the sand of infested beaches, and their response to chemical treatment, the monthly and annual cycles of the adult midge, and the possibilities of achieving laboratory oviposition, as a first step to laboratory colonisation. The distribution of eggs, larvae and pupae of C. molestus was found to be mostly concentrated around, but below, mean tide level. They also occurred well below the mean tide level. Eggs and larvae have been recovered from as deep as 10 cm in the sand. A seasonal study of the juveniles of this species indicated that they were more strongly influenced by tides than seasons. After a routine pest-control larviciding treatment, a beach recolonisation study revealed that beaches become suitable for oviposition approximately two months after treatment. Large larvae invaded the sprayed areas within days of treatment, which suggests the existence of a refuge outside of the reach of the insecticide. Larvae found in clean (egg- and larva-free), isolated sand containers, placed on the study beach, indicated that larvae could swim in or on the water as a way of moving around the beach. Extended bite-rate studies highlighted the existence of four peaks in adult midge biting activity during the course of a year, around the mid seasons. The strongest peaks of activity were found to be in autumn and spring, but the data suggest that the species undergoes four generations in a year. Through a series of trial-and-error experiments, oviposition under laboratory conditions was achieved. Although the time from blood-feeding to egg maturation is not yet well determined, it occurs within an eight day mean survival period. Blood quality appears critical for adult blood-fed midge survival. Midges fed on the blood of a volunteer who was frequently exposed to midge bites do not live long enough to mature its eggs. The partial ovarial development of one unfed adult female, reared in the laboratory, indicates that C. molestus is facultatively anautogenous.
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Wells, Alice. "The systematics and biogeography of Australian hydroptilidae (Trichoptera) /." Title page, contents and abstract only, 1986. http://web4.library.adelaide.edu.au/theses/09PH/09phw453.pdf.
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Sutcliffe, Karen. "The conservation status of aquatic insects in South-Western Australia /." Access via Murdoch University Digital Theses Project, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040430.153605.
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Sutcliffe, Karen Elizabeth. "The conservation status of aquatic insects in south-western Australia." Thesis, Sutcliffe, Karen Elizabeth (2003) The conservation status of aquatic insects in south-western Australia. PhD thesis, Murdoch University, 2003. https://researchrepository.murdoch.edu.au/id/eprint/327/.
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Freshwater ecosystems in south-western Australia have been extensively altered over the last two centuries as a result of human activities. The effect this has had on aquatic fauna, particularly invertebrates, is largely unknown because of inadequate knowledge of the pre-existing fauna. Future changes in the composition of aquatic fauna will also go undetected unless current distributions of existing species are well documented.
This thesis addresses the problem by investigating the current distributions and conservation status of aquatic insects in south-western Australia from three orders: Odonata, Plecoptera and Trichoptera. Extensive distributional data was collected by identifying larval specimens from a large number of samples collected throughout the south-west as part of an Australia-wide macroinvertebrate bioassessment project. In addition, a database created from a species-level biological study of the wheatbelt region of Western Australia was utilised, and previously published records of occurrence for species within the south-west were compiled. These results were then used to assess the conservation status of each species using the IUCN red list criteria.
Environmental parameters measured at time of sampling were also examined using logistic regression to determine which factors are important in influencing the distributions of aquatic insects in south-western Australia. The conservation value of sites based on Odonata, Plecoptera and Trichoptera compositions was also determined and the degree of protection provided for sites of high conservation value investigated. The high rainfall forested region of the south-west was found to be important for a large number of species, including the majority of those found to be rare and/or restricted.
Overall, 37% of species were found to be threatened, with the Trichoptera containing both the greatest number and highest proportion of threatened species. Logistic regression results generally agreed with the distributions obtained for each species, with rainfall and other parameters indicative of streams in the headwaters of forested catchments being positively associated with species found to be restricted to the high rainfall region. Two parameters known to be affected by human disturbance in the south-west, conductivity and nutrient concentrations, were found to be important in determining the occurrence of many species and this could have important consequences for aquatic insect conservation. Widespread species occurring within the low rainfall region of the south-west did not show as many significant relationships to measured environmental parameters, possibly due to their greater ecological tolerances and adaptations which allow them to persist in a low rainfall environment. The implications of results are discussed, and recommendations for the conservation and management of aquatic insects in south-western Australia are given.
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Sutcliffe, Karen Elizabeth. "The conservation status of aquatic insects in south-western Australia." Murdoch University, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040430.153605.
Full textAbstract:
Freshwater ecosystems in south-western Australia have been extensively altered over the last two centuries as a result of human activities. The effect this has had on aquatic fauna, particularly invertebrates, is largely unknown because of inadequate knowledge of the pre-existing fauna. Future changes in the composition of aquatic fauna will also go undetected unless current distributions of existing species are well documented.
This thesis addresses the problem by investigating the current distributions and conservation status of aquatic insects in south-western Australia from three orders: Odonata, Plecoptera and Trichoptera. Extensive distributional data was collected by identifying larval specimens from a large number of samples collected throughout the south-west as part of an Australia-wide macroinvertebrate bioassessment project. In addition, a database created from a species-level biological study of the wheatbelt region of Western Australia was utilised, and previously published records of occurrence for species within the south-west were compiled. These results were then used to assess the conservation status of each species using the IUCN red list criteria.
Environmental parameters measured at time of sampling were also examined using logistic regression to determine which factors are important in influencing the distributions of aquatic insects in south-western Australia. The conservation value of sites based on Odonata, Plecoptera and Trichoptera compositions was also determined and the degree of protection provided for sites of high conservation value investigated.The high rainfall forested region of the south-west was found to be important for a large number of species, including the majority of those found to be rare and/or restricted.
Overall, 37% of species were found to be threatened, with the Trichoptera containing both the greatest number and highest proportion of threatened species. Logistic regression results generally agreed with the distributions obtained for each species, with rainfall and other parameters indicative of streams in the headwaters of forested catchments being positively associated with species found to be restricted to the high rainfall region. Two parameters known to be affected by human disturbance in the south-west, conductivity and nutrient concentrations, were found to be important in determining the occurrence of many species and this could have important consequences for aquatic insect conservation. Widespread species occurring within the low rainfall region of the south-west did not show as many significant relationships to measured environmental parameters, possibly due to their greater ecological tolerances and adaptations which allow them to persist in a low rainfall environment. The implications of results are discussed, and recommendations for the conservation and management of aquatic insects in south-western Australia are given.
7
Wang, Haikou Physical Environmental & Mathematical Sciences Australian Defence Force Academy UNSW. "Evaluation of insect monitoring radar technology for monitoring locust migrations in inland Eastern Australia." Awarded by:University of New South Wales - Australian Defence Force Academy, 2008. http://handle.unsw.edu.au/1959.4/38923.
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To evaluate the utility of insect monitoring radar (IMR) technology for long-term monitoring of insect migration, a mini-network of two IMR units in Bourke, NSW, and Thargomindah, Qld, and a base-station server in Canberra, ACT, was set up in eastern Australia. The IMR operated automatically every night under the control of a personal computer that also conducted data acquisition and processing. Digitisation of radar signals, their analysis (delimitation of echoes from background noise and adjoining echoes, followed by extraction of estimates for each target's speed, displacement direction, body alignment, radar cross-section, and wingbeat frequency and modulation pattern), and generation of observation summaries were implemented as a fully automated procedure. Wingbeat frequency was found to be retrievable from the IMR's rotary-beam signals, and this allowed each individual target to be characterised by its wingbeat as well as its size and shape. By drawing on ancillary information from the Australian Plague Locust Commission's database of field survey and light trap records, the echo characters indicative of Australian plague locust, Chortoicetes terminifera (Walker), were identified. Using these, about 140 nights with detectable plague locust migrations were identified for the Bourke IMR site during 1998 - 2001 and 31 nights for Thargomindah during 1999 - 2000. Analysis of these nights confirmed that C. terminifera migrates in association with disturbed weather, especially tropical troughs, in eastern Australia. Trajectory simulation based on IMR-derived displacement directions and flight speeds allowed the identification of population movements likely to reach favourable habitats and thus to develop rapidly and possibly cause a plague. The outbreak during 1999 - 2001 most likely originated from the southeastern agricultural belt after migrations and multiplications over several generations. The IMR observations demonstrated that C. terminifera migrates over long distances with the wind at night and indicated that it may have an orientation behaviour that prevents it from being taken too far into the arid inland, a trait that could be highly adaptive in this environment. The two IMRs were operational for more than 85% of scheduled time during the study period and provided a wealth of information of potential value for locust management and migration research
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Kasper, Marta L. "The population ecology of an invasive social insect, Vespula germanica (Hymenoptera : vespidae) in South Australia /." Title page, table of contents and abstract only, 2004. http://web4.library.adelaide.edu.au/theses/09PH/09phk1928.pdf.
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Petersen, Christopher, and Jonathon Georgy. "The effect of suitcase concealment on the insect colonisation: A pilot study in Western Australia." Thesis, Petersen, Christopher and Georgy, Jonathon (2017) The effect of suitcase concealment on the insect colonisation: A pilot study in Western Australia. Masters by Coursework thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/37834/.
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Knowing and understanding the stages involved in the decomposition process of a cadaver is crucial in the ability to accurately estimate the post-mortem interval (PMI) or time since death (TSD). A large amount of information about the PMI can be provided by the state of decomposition as well as the fauna colonizing the body. This is the case if decomposition is treated as a semi-continuous variable and used in conjunction with accumulated degree days (ADD) and by the successional waves of the insects and other arthropods consuming the body. PMI is a pivotal information in forensic investigations as it can be used in homicide cases by personnel of law enforcement for crime scene reconstruction and for the exclusion of potential perpetrators as well as to support witness testimony. Establishing the range of natural events and environmental conditions that were likely to have affected the remains with the passing of seasons can also be aided by knowing the PMI, permitting a more thorough taphonomic analysis.
However, the use of a method to conceal a body (such as burials, wrapping, suitcases) may affect changes within a body and the associated entomological activity that are different to bodies that are exposed to the environment. Therefore, it is necessary to understand the unique taphonomic processes that occur when a body is concealed. While numerous types of concealment have been researched and investigated in the past, minimal research has been specifically related to concealment within a suitcase. This literature review aims to address the effects of different concealment methods, with main focus on suitcase concealment, on the decomposition rate and entomological activity of a cadaver.
KEYWORDS: forensic science, forensic entomology, taphonomy, decomposition, accumulated degree days, post-mortem interval, concealment
10
Lambert, Adam Matthew. "Native and exotic Phragmites australis in Rhode Island : distribution and differential resistance to insect herbivores /." View online ; access limited to URI, 2005. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3186908.
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Rochester, W. A. "The migration systems of Helicoverpa punctigera (Wallengren) and Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in Australia /." [St. Lucia, Qld. : s.n.], 1999. http://adt.library.uq.edu.au/public/adt-QU2001.0019/index.html.
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Butler, G. D. Jr, and T. J. Henneberry. "Microplitis sp. From Australia (Hymenoptera: Braconidae): Development in the Beet Armyworm and Adult Longevity in Relation to Temperature." College of Agriculture, University of Arizona (Tucson, AZ), 1991. http://hdl.handle.net/10150/208377.
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The effects of temperature on development and longevity of a Microplitis sp. from Australia on the beet armyworm, Spodoptera erigua (Hübner) was studied in the laboratory. Time of development ranged from 25 days at 15°C to 6.2 days at 27.5 °C. The parasite developed twice as fast as its beet armyworm host. Average longevities of male and female parasites were not significantly different.
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Plumier, Benjamin Mark. "3D ecosystem modeling of aeration and fumigation in Australian grain silos to improve efficacy against insects." Diss., Kansas State University, 2018. http://hdl.handle.net/2097/38833.
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Doctor of PhilosophyDepartment of Grain Science and Industry
X. Susan Sun
With continued population growth, more food production will be required with lower resource inputs. A significant drain on resources is post-harvest loss due to insects, which results in loss of product, quality and market access, and increased grain spoilage. Aeration and fumigation are key tools to control insect growth in stored grains and grain foods. The implementation of aeration strategies in Australia is made difficult by the warm subtropical climate, meanwhile the success of fumigation is being threatened by the spread of insect resistance to the fumigant phosphine. This dissertation project seeks to improve the understanding of aeration and fumigation by modifying the Maier-Lawrence (M-L) 3D ecosystem model by adding insect growth equations and quantifying fumigant loss from sealed bulk grain silos. The improved model was used to examine aeration under Australian conditions, validate its capability to accurately describe fumigant concentrations during silo fumigation, determine the extent to which fumigations are influenced by operational variables and environmental conditions, and validate its capability to describe fumigant concentrations post-fumigation in order to investigate the time needed to clear a grain storage silo of fumigant in order to assure worker safety. Six aeration strategies were evaluated under Australian conditions. Of these strategies, two were found to be effective in lowering temperatures, i.e., fans were turned on when ambient temperature was less than 20oC, and less than internal grain temperature. The strategy based on temperature differential was the most effective because it cooled the interior of the grain mass with the least amount of energy (using the fewest fan run hours, and reaching 15oC an average of 11 days after than the fastest strategy). Using a 0oC temperature differential was the most effective strategy in terms of reducing insect growth. The expanded (M-L-P) model was then validated based on experimental fumigant concentrations. The model was effective in reproducing average fumigant concentrations and fumigant trends vertically through the grain mass, but was not able to reproduce lateral fumigant variations. Verifications of the model with two different periods of phosphine release (i.e., 24h and 30h) were tested. Based on a 24h phosphine release period the predicted Ct-product differed from the experimental value by 0.9%. A 30h release period predicted a Ct-product that differed by 4.3% from the experimental value but it was more accurate during the times of highest concentration. Increases in leakage reduced fumigant concentrations, but the size of the effect decreased as leakage grew. Increasing temperature and wind speed in the model led to decreased phosphine concentrations, with temperature changes having a more significant impact overall than wind speed changes for the conditions investigated. Decreasing silo surface area to volume ratio dampened the impact of changing weather conditions on phosphine concentrations. A fumigant venting experiment was conducted in a silo at Lake Grace, Australia, to investigate full scale desorption. Two equations estimating fumigant desorption were tested, with an average of 65.5% and -86.3% error. The length of venting periods was simulated to quantify hours needed to mitigate hazardous conditions. For the scenarios investigated 10 to 24 h of venting were needed to reduce residual fumigant concentration below 0.3 ppm depending on simulation assumptions.
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Reels, Graham Thomas. "Management strategies for the reed Phragmites australis (CAV.) Steud. at Mai Po Marshes Nature Reserve, Hong Kong, with observations on the associated insect Fauna /." Hong Kong : University of Hong Kong, 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20665799.
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Keshlaf, Marwan M. "An assessment of honeybee foraging activity and pollination efficacy in Australian Bt cotton." View thesis, 2008. http://handle.uws.edu.au:8081/1959.7/38265.
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Thesis (Ph.D.)--University of Western Sydney, 2008.A thesis submitted to the University of Western Sydney, College of Health and Science, Centre for Plant and Food Science, in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliography.
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Wan, Jing. "Prediction of the potential geographic distributions and risk assessment of four trade impacting invasive insect pests in Australia and China." Thesis, Wan, Jing (2020) Prediction of the potential geographic distributions and risk assessment of four trade impacting invasive insect pests in Australia and China. PhD thesis, Murdoch University, 2020. https://researchrepository.murdoch.edu.au/id/eprint/61455/.
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This thesis explores biological invasion through the potential pest distribution and risk analysis of tomato potato psyllid (TPP), Bactericera cockerelli; fall armyworm (FAW), Spodoptera frugiperda; Bactrocera bryoniae; and Bactrocera neohumeralis. Through better understanding of the pest distribution and risk analysis agricultural management policies can be implemented, and containment and eradication actions taken.
The TPP is a psyllid native to North America that has recently invaded Australia. The potential for economic losses accompanying invasions of TPP and its associated bacterial plant pathogen Candidatus Liberibacter solanacearum (CLso), has caused much concern. Here, we employed ecological niche models to predict environments suitable for TPP/CLso on a global scale and then evaluated the extent to which global potato cultivation is at risk. A total of 86 MaxEnt models were built using various combinations of settings and climatic predictors, and the best model based on model evaluation metrics was selected. Climatically suitable habitats were identified in Eurasia, Africa, South America, and Australasia. Intersecting the predicted suitability map with land use data showed that 79.06% of the global potato production, 96.14% of the potato production acreage in South America and Eurasia, and all the Australian potato production are at risk. The information generated in this study increases knowledge of the ecology of TPP/CLso and can be used by government agencies to make decisions about preventing the spread of TPP and CLso across the globe.
Fall armyworm (FAW), S. frugiperda is native to the Americas and it has rapidly invaded 47 African countries and 18 Asian countries since the first detection of invasion into Nigeria and Ghana in 2016. It is regarded as a ‘super pest’ based on its host range (at least 353 host plants), its inherent ability to survive in a wide range of habitats, its strong migration ability, high fecundity, rapid development of resistance to insecticides/viruses and its gluttonous characteristics. In order to better understand the seasonal geographic distributions of S. frugiperda, we employed ecological niche models of MaxEnt to predict potential year-round breeding and seasonal distribution for S. frugiperda on a global scale and in Australia. A total of 74 MaxEnt models were built using various combinations of regularization multiplier, feature class and climatic variables, and the best model based on model evaluation metrics was selected, with an evaluation of dominant climatic factors that control its distribution. The results suggest that the temperature factor was the most important variable affecting the seasonal distribution of S. frugiperda. No matter where in the world, the year-round breeding distribution model predicted smaller portions of fall armyworm's ranges than the seasonal model. S. frugiperda had a high remaining invasion potential in Australia, posing a significant threat to its biosecurity, food security and agricultural productivity.
Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive fruit flies and considered major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific. Ecological niche modelling MaxEnt was employed to predict the potential geographic distribution of B. bryoniae and B. neohumeralis across the world and particularly in China with the occurrence data of these two species. B. bryoniae and B. neohumeralis exhibit similar potential geographic distribution ranges across the world and in China, and included southern Asia, the central and the southeast coast of Africa, southern North America, northern and central South America, and Australia. While within China, most of the southern Yangtze River area was found suitable for these two species. Notably, southern China was considered to have the highest risk of B. bryoniae and B. neohumeralis invasions. Our study identifies the regions at high risk for potential establishment of B. bryoniae and B. neohumeralis in the world and particularly in China and informs government officials to develop policies for inspection and biosecurity/quarantine measures to prevent and control their invasion.
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Vezvaei, Ali. "Pollination studies in almond." Title page, contents and summary only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09phv597.pdf.
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Reels, Graham Thomas. "Management strategies for the reed Phragmites australis (CAV.) Steud. at Mai Po Marshes Nature Reserve, Hong Kong, with observations on theassociated insect Fauna." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31211835.
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Muthuthantri, Weerawickramage Sakuntala Nayanatara. "Population phenology of the tropical fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), in Queensland, Australia." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/16671/1/Weerawickramage_Muthuthantri_Thesis.pdf.
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Bactrocera tryoni, the Queensland fruit fly, is established along the entire Australian east coast. It is a major pest of horticulture and arguably the worst horticultural insect pest in Australia. Adult flies lay eggs into fruit and resultant larvae feed on the flesh of the fruit. The population biology of B. tryoni has been well studied in temperate regions, where it has been established that climatic factors, particularly temperature and rainfall, limit population growth. In contrast, in subtropical and tropical regions, the population dynamics of the fly have been little studied. This thesis investigates the fly's phenology and abundance changes across subtropical and tropical Queensland and asks what factors govern the population cycles of B. tryoni in this state. Winter breeding and abundance of the fly, a component of the seasonal cycle which in south-east Queensland is fundamentally different from that observed in temperate Australia, is also investigated.
A historical, extensive multi-year and multi-site trapping data set with from across Queensland was analysed to look at the effects of temperature, rainfall and relative humidity on B. tryoni trap catch. Trap data was further compared with the predicted phenology data generated by a DYMEX® based B. tryoni population phenology model. The phenology model used was based on a previously published model, but was also modified to more explicitly look at the effects of host plant availability and the presence or absence of non-reproductive over-wintering flies. Over-wintering field cage studies and a winter-spring field trapping study, both carried out in Brisbane, supplied additional data on B. tryoni's population abundance and capacity to breed during winter in the subtropics.
Results show significant variation of monthly fly abundance for nine sites across Queensland. Abundance changed across sites in non-predictable ways. Annual population phenology within a site was, for some sites, highly consistent from year to year, but inconsistent for other sites. All sites in the subtropics showed some form of population depression during the cooler months, but breeding was continuous, albeit reduced at nearly all sites. Some tropical sites, where the climate is regarded as highly favourable for B. tryoni, still showed dramatic peaks and troughs in annual population abundance. There were relatively few significant correlations observed between weather factors and fly populations for any site. Output from the DYMEX population model suggested that fruit availability is a major driver of population dynamics in the tropical north of the state, while weather is more important in the subtropical south. The population dynamics of B. tryoni at sites along the central Queensland coast, where it is assumed that a mix of both weather and host fruit availability drive local populations, were poorly captured by the population model. Field cage results showed that B. tryoni successfully bred during winter in Brisbane, with pupal emergence starting in mid-winter (1st week of August), peaking in early spring (2nd week of September). Trap catch at orchards in Brisbane increased with increasing temperature and fruit availability, but diminished with decreasing temperature and fruit availability.
The results suggest that B. tryoni has an optimal climate for population growth in the tropics, but fruit availability for offspring production limits population growth. In the subtropics however, both climate and fruit availability determine the population size. Winter temperatures are marginal for B. tryoni population growth in the subtropics.
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Muthuthantri, Weerawickramage Sakuntala Nayanatara. "Population phenology of the tropical fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), in Queensland, Australia." Queensland University of Technology, 2008. http://eprints.qut.edu.au/16671/.
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Bactrocera tryoni, the Queensland fruit fly, is established along the entire Australian east coast. It is a major pest of horticulture and arguably the worst horticultural insect pest in Australia. Adult flies lay eggs into fruit and resultant larvae feed on the flesh of the fruit. The population biology of B. tryoni has been well studied in temperate regions, where it has been established that climatic factors, particularly temperature and rainfall, limit population growth. In contrast, in subtropical and tropical regions, the population dynamics of the fly have been little studied. This thesis investigates the fly's phenology and abundance changes across subtropical and tropical Queensland and asks what factors govern the population cycles of B. tryoni in this state. Winter breeding and abundance of the fly, a component of the seasonal cycle which in south-east Queensland is fundamentally different from that observed in temperate Australia, is also investigated. A historical, extensive multi-year and multi-site trapping data set with from across Queensland was analysed to look at the effects of temperature, rainfall and relative humidity on B. tryoni trap catch. Trap data was further compared with the predicted phenology data generated by a DYMEX® based B. tryoni population phenology model. The phenology model used was based on a previously published model, but was also modified to more explicitly look at the effects of host plant availability and the presence or absence of non-reproductive over-wintering flies. Over-wintering field cage studies and a winter-spring field trapping study, both carried out in Brisbane, supplied additional data on B. tryoni's population abundance and capacity to breed during winter in the subtropics. Results show significant variation of monthly fly abundance for nine sites across Queensland. Abundance changed across sites in non-predictable ways. Annual population phenology within a site was, for some sites, highly consistent from year to year, but inconsistent for other sites. All sites in the subtropics showed some form of population depression during the cooler months, but breeding was continuous, albeit reduced at nearly all sites. Some tropical sites, where the climate is regarded as highly favourable for B. tryoni, still showed dramatic peaks and troughs in annual population abundance. There were relatively few significant correlations observed between weather factors and fly populations for any site. Output from the DYMEX population model suggested that fruit availability is a major driver of population dynamics in the tropical north of the state, while weather is more important in the subtropical south. The population dynamics of B. tryoni at sites along the central Queensland coast, where it is assumed that a mix of both weather and host fruit availability drive local populations, were poorly captured by the population model. Field cage results showed that B. tryoni successfully bred during winter in Brisbane, with pupal emergence starting in mid-winter (1st week of August), peaking in early spring (2nd week of September). Trap catch at orchards in Brisbane increased with increasing temperature and fruit availability, but diminished with decreasing temperature and fruit availability. The results suggest that B. tryoni has an optimal climate for population growth in the tropics, but fruit availability for offspring production limits population growth. In the subtropics however, both climate and fruit availability determine the population size. Winter temperatures are marginal for B. tryoni population growth in the subtropics.
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Tarlinton, Boyd. "Phylosymbiosis and the microbiome of the native Australian stingless bee Tetragonula carbonaria." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/212693/1/Boyd_Tarlinton_Thesis.pdf.
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Tetragonula carbonaria (Smith 1854) is a native Australian stingless bee, hosting a diverse range of bacterial symbionts. T. carbonaria is used as a model to explore how relationships between host insects and the microbiome occur and can be detected within a single species, shedding light on how host-microbiome associations arise and are maintained across the corbiculate bees. Host-microbiome relationships are considered through the lens of phylosymbiosis. Methods for detecting phylosymbiosis are explored; different bioinformatics and statistical techniques are compared, with implications for future studies. Bayesian modelling is used to predict possible routes of acquisition of bee symbionts.
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Toussaint, Emmanuel FA. "Insects as a model to puzzle out mechanisms of lineage diversification in the Indomalayan / Australasian archipelago." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-177872.
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Dean, Timothy J. Physical Environmental & Mathematical Sciences Australian Defence Force Academy UNSW. "Development and evaluation of automated radar systems for monitoring and characterising echoes from insect targets." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Physical, Environmental and Mathematical Sciences, 2007. http://handle.unsw.edu.au/1959.4/38667.
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This thesis describes the construction of a mobile Insect Monitoring Radars (IMR) and investigations of: the reliability of IMRs for observing insect migration in inland Australia; possible biases in IMR migration estimates; the relation between an insect???s size and its radar properties; radar discrimination between insect species; the effect of weather on the migrations of Australian plague locusts and of moths; the scale of these migrations; and here IMRs are best located. The principles of entomological radar design, and the main features of insect migration in inland Australia, are reviewed. The main procedures used in the study are: calculation of radar performance and of insect radar cross sections (RCSs); reanalysis of a laboratory RCS dataset; statistical analysis of a fouryear dataset of IMR and weather observations; and a field campaign using both two existing fixed IMRs and the new mobile unit. Statistical techniques used include correlation, multiple regression, discriminant analysis, and principal components analysis. The original results of this work include design details of the mobile IMR, extension of radar performance calculations to IMRs and evaluation of flight speed biases, a holistic approach to IMR design, the relation of insect RCS magnitudes and polarization patterns to morphological variables, an estimate of the accuracy of the retrieved parameters, evaluations of three approaches (oneparameter, theory-based, and a novel two-stage method) to target identification, and verification of inferred target identities using results from nearby light traps. Possible sites for future IMRs are identified. The major conclusions are that: a mobile IMR can be built with a performance equal to that of a fixed IMR but at half the cost; significant biases in the signal processing results arise from insect speed; locusts and moths can be distinguished if all RCS parameters are used; IMRs can be designed to match particular requirements; weather has a significant effect on insect migration, the best single predictor of insect numbers being temperature; moonlight has no effect; the spatial correlation of migration properties falls to 50% at a separation of 300 km; and migrating insects can be carried by the wind for 500 km in a single night
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Maroni, Paige. "Sexual conflict and secondary sexual traits in West Australian Riffle Bugs (Insecta: Hemiptera: Veliidae). An overview of the relationship between morphology and behaviour." Thesis, Maroni, Paige (2017) Sexual conflict and secondary sexual traits in West Australian Riffle Bugs (Insecta: Hemiptera: Veliidae). An overview of the relationship between morphology and behaviour. Honours thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/40076/.
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How and why an animal chooses its mate is characteristic of morphological and behavioural adaptations developed to maximize reproductive success. This thesis compares patterns of sexual dimorphism (through micro-CT analyses) in three Veliidae species (Microvelia oceanica, Nesidovelia peramoena and N. herberti) and aims to explain these in the context of sexual conflict. Sexually antagonistic morphological and behavioural traits were also of interest and were documented through examinations of male-female reproductive interactions of N. peramoena via video recordings and micro-CT scan outputs of interlocked pairs, frozen in copula. Interlocked pairs were captured through a new technique for snap freezing surface dwelling insects, which was developed within this thesis. In all three species, females were found to be generally larger than males and macropters larger overall than apters, as is often the case with insects. All specimens examined were documented to express some form of a secondary sexual trait which are likely to be coevolving in an evolutionary arms race. In females, these resistance traits variously included connexival convergence, genital concealment and setal tufts. Females of N. peramoena showed strong pre-mating resistance behaviours evidenced by either fleeing or vigorously struggling during 96% of all observed intersexual interactions. In both Nesidovelia species, males expressed persistence traits such as a ventral abdominal process on segment 8 and ventral abdominal segment 7 medial concavity. Through this study, these traits are now known to act as a pregenital clamp grasping to the females on the underside of her proctiger during the pre-mating struggle, as well as during copulation. Interestingly, while macropterous males retain their secondary sexual traits, macropterous females were found to lack their putative resistance traits, suggesting either an energetic or mechanical trade-off in development. This study is one of the first to provide evidence that sexual conflict is the likely driving force behind the behaviours and sexual dimorphism in the Veliidae. The array of different secondary sexual traits makes those in the Gerridae (the current model group for sexual conflict and sexually antagonistic character studies) seem tame in comparison. Within these riffle bug species, unique coevolved male-female grasping and anti-grasping structures provide strong evidence for sexual antagonism in veliid mating that have not previously been documented in any surface dwelling insects.
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Michalakis, Ioannis. "Evolution des systèmes plantes hôtes - insectes parasites : approche théorique et expérimentale." Montpellier 2, 1992. http://www.theses.fr/1992MON20008.
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Des modeles theoriques montrent l'importance des flux geniques par la fixation de mutants rares a un locus sous-dominant, et pour l'evolution de genes codant pour la selection d'habitat. Ces resultats sont utilises pour expliquer la formation de races geographiques (allopatiques) et l'absence des races d'hotes (sympatiques) chez larinus cynarae, insecte parasite des chardons du genre onopordum et cynara. Les potentialites des larinus pour la lutte biologique contre onopordum en australie sont discutees
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Yan, Jwo-Yee. "Studies on the behaviour of males of California red scale Aonidiella aurantii (Maskell)." Title page, contents and summary only, 1985. http://web4.library.adelaide.edu.au/theses/09A/09ay21.pdf.
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Baker, Jeanine. "Factors affecting the establishment of a classical biological control agent, the horehound plume moth (Wheeleria spilodactylus) in South Australia." Title page, summary and contents only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phb1677.pdf.
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Includes bibliographical references (leaves 168-198) The horehound plume moth (Wheeleria spilodactylus Curits), an agent introduced to control the invasive weed horehound (Murrubium vulgare L.), was used as a model system to investigate factors believed to influence the successful establishment of an introduced natural enemy. Retrospectively tests the use of generic population viability analysis and decision making tools for determining optimal release strategies for the horehound plume moth in South Australia and to compare outcomes with the emprical data collected during the course of this project
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Guthrie, Ruth J. "Patterns of invertebrate distribution and abundance on Cordyline australis in human-modified landscapes." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/1235.
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Fragmentation of forest habitat by urban and rural development has had profound effects on the distribution and abundance of many native species; however, little is known about the ecological processes driving patterns in community structure (species richness and composition) of host-specialised herbivores in modified habitats. I examined patterns in community structure of 9 specialist and 19 generalist invertebrate herbivores of cabbage trees (Cordyline australis Laxmanniaceae) across a highly-modified landscape. I found that, although species richness of specialists was highest in forest sites, the majority of host-specialised species were not restricted to forest habitats and were as widespread as many generalists. In terms of site occupancy, only two specialist and four generalist species were rare. I show that patterns of species occupancy and abundance reflect differing susceptibility to habitat modification, with landscape-level variation an important predictor of abundance for nearly all species. When species occurrences and life history traits were considered I did not find strong evidence for the importance of dispersal ability, which suggests that habitat variability had a stronger organising effect on the community. In a replicated common garden experiment, I found distinct regional patterns in the community structure of the specialist invertebrates occurring on different phylogenetic groups of C. australis. In contrast, community structure of generalist herbivores did not differ significantly among host genotypes. I speculate these patterns are due to historical changes in the distribution of cabbage trees in the Southern phylogenetic region that caused specialised herbivores to become locally adapted on populations of low genetic diversity following expansion after the last glacial maximum. However, this consistent selection pressure did not occur in the Northern region where C. australis habitat has been more consistently available over the past tens of thousands of years, reflected in higher host genetic diversity. This study has advanced our understanding of the patterns in community structure of an indigenous, host-specialised fauna in a highly modified and fragmented urban and rural landscapes.
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Hill, Stuart John. "Pollination of almond (Prunus dulcis (Mill.) D.A. Webb)." Title page, contents and summary only, 1987. http://web4.library.adelaide.edu.au/theses/09A/09ah648.pdf.
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Alfaro, Lemus Ana Lilia. "Factors influencing the control of citrophilous mealybug Pseudococcus calceolarie (Maskell) by Coccophagus gurneyi Compere in the Riverland of South Australia." Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09IM/09iml562.pdf.
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Includes bibliographical references (leaves 102-114) The highly successful biological control of the citrophilous mealybug Pseudococcus calceolarie (Maskell) (CM) by the parasitic wasp Coccophagus gurneyi Compere in several countries led to the release of this parasitoid in the Riverland of South Australia as part of an integrated pest management program. However CM has not been successfully controlled in this region. The results of this study may help to explain the lack of effective biological control of CM in Riverland citrus.
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Toussaint, Emmanuel F. A. [Verfasser], and Gerhard [Akademischer Betreuer] Haszprunar. "Insects as a model to puzzle out mechanisms of lineage diversification in the Indomalayan / Australasian archipelago [[Elektronische Ressource]] / Emmanuel F. A. Toussaint. Betreuer: Gerhard Haszprunar." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://d-nb.info/1069743305/34.
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Toussaint, Emmanuel F. A. Verfasser], and Gerhard [Akademischer Betreuer] [Haszprunar. "Insects as a model to puzzle out mechanisms of lineage diversification in the Indomalayan / Australasian archipelago [[Elektronische Ressource]] / Emmanuel F. A. Toussaint. Betreuer: Gerhard Haszprunar." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-177872.
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Davila, Yvonne Caroline. "Pollination ecology of Trachymene incisa (Apiaceae): Understanding generalised plant-pollinator systems." University of Sydney, 2006. http://hdl.handle.net/2123/1896.
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Doctor of Philosophy (PhD)A renewed focus on generalised pollinator systems has inspired a conceptual framework which highlights that spatial and temporal interactions among plants and their assemblage of pollinators can vary across the individual, population, regional and species levels. Pollination is clearly a dynamic interaction, varying in the number and interdependence of participants and the strength of the outcome of the interaction. Therefore, the role of variation in pollination is fundamental for understanding ecological dynamics of plant populations and is a major factor in the evolution and maintenance of generalised and specialised pollination systems. My study centred on these basic concepts by addressing the following questions: (1) How variable are pollinators in a generalised pollination system? To what degree do insect visitation rates and assemblage composition vary spatially among populations and temporally among flowering seasons? (2) How does variation in pollinators affect plant reproductive success? I chose to do this using a model system, Trachymene incisa subsp. incisa (Apiaceae), which is a widespread Australian herbaceous species with simple white flowers grouped into umbels that attract a high diversity of insect visitors. The Apiaceae are considered to be highly generalist in terms of pollination, due to their simple and uniform floral display and easily accessible floral rewards. Three populations of T. incisa located between 70 km and 210 km apart were studied over 2-3 years. The few studies investigating spatial and temporal variation simultaneously over geographic and yearly/seasonal scales indicate that there is a trend for more spatial than temporal variation in pollinators of generalist-pollinated plants. My study showed both spatial and temporal variation in assemblage composition among all populations and variation in insect visitation rates, in the form of a significant population by year interaction. However, removing ants from the analyses to restrict the assemblage to flying insects and the most likely pollinators, resulted in a significant difference in overall visitation rate between years but no difference in assemblage composition between the Myall Lakes and Tomago populations. These results indicate more temporal than spatial variation in the flying insect visitor assemblage of T. incisa. Foraging behaviour provides another source of variation in plant-pollinator interactions. Trachymene incisa exhibits umbels that function as either male or female at any one time and offer different floral rewards in each phase. For successful pollination, pollinators must visit both male and female umbels during a foraging trip. Insects showed both preferences and non-preferences for umbel phases in natural patches where the gender ratio was male biased. In contrast, insects showed no bias in visitation during a foraging trip or in time spent foraging on male and female umbels in experimental arrays where the gender ratio was equal. Pollinator assemblages consisting of a mixture of different pollinator types coupled with temporal variation in the assemblages of populations among years maintains generalisation at the population/local level. In addition, spatial variation in assemblages among populations maintains generalisation at the species level. Fire alters pollination in T. incisa by shifting the flowering season and reducing the abundance of flying insects. Therefore, fire plays an important role in maintaining spatial and temporal variation in this fire-prone system. Although insect pollinators are important in determining the mating opportunities of 90% of flowering plant species worldwide, few studies have looked at the effects of variation in pollinator assemblages on plant reproductive success and mating. In T. incisa, high insect visitation rates do not guarantee high plant reproductive success, indicating that the quality of visit is more important than the rate of visitation. This is shown by comparing the Agnes Banks and Myall Lakes populations in 2003: Agnes Banks received the highest visitation rate from an assemblage dominated by ants but produced the lowest reproductive output, and Myall Lakes received the lowest visitation rate by an assemblage dominated by a native bee and produced the highest seedling emergence. Interestingly, populations with different assemblage composition can produce similar percentage seed set per umbel. However, similar percentage seed set did not result in similar percentage seedling emergence. Differences among years in reproductive output (total seed production) were due to differences in umbel production (reproductive effort) and proportion of umbels with seeds, and not seed set per umbel. Trachymene incisa is self-compatible and suffers weak to intermediate levels of inbreeding depression through early stages of the life cycle when seeds are self-pollinated and biparentally inbred. Floral phenology, in the form of synchronous protandry, plays an important role in avoiding self-pollination within umbels and reducing the chance of geitonogamous pollination between umbels on the same plant. Although pollinators can increase the rate of inbreeding in T. incisa by foraging on both male and female phase umbels on the same plant or closely related plants, most consecutive insect movements were between plants not located adjacent to each other. This indicates that inbreeding is mostly avoided and that T. incisa is a predominantly outcrossing species, although further genetic analyses are required to confirm this hypothesis. A new conceptual understanding has emerged from the key empirical results in the study of this model generalised pollination system. The large differences among populations and between years indicate that populations are not equally serviced by pollinators and are not equally generalist. Insect visitation rates varied significantly throughout the day, highlighting that sampling of pollinators at one time will result in an inaccurate estimate and usually underestimate the degree of generalisation. The visitor assemblage is not equivalent to the pollinator assemblage, although non-pollinating floral visitors are likely to influence the overall effectiveness of the pollinator assemblage. Given the high degree of variation in both the number of pollinator species and number of pollinator types, I have constructed a model which includes the degree of ecological and functional specialisation of a plant species on pollinators and the variation encountered across different levels of plant organisation. This model describes the ecological or current state of plant species and their pollinators, as well as presenting the patterns of generalisation across a range of populations, which is critical for understanding the evolution and maintenance of the system. In-depth examination of pollination systems is required in order to understand the range of strategies utilised by plants and their pollinators, and I advocate a complete floral visitor assemblage approach to future studies in pollination ecology. In particular, future studies should focus on the role of introduced pollinators in altering generalised plant-pollinator systems and the contribution of non-pollinating floral visitors to pollinator assemblage effectiveness. Comparative studies involving plants with highly conserved floral displays, such as those in the genus Trachymene and in the Apiaceae, will be useful for investigating the dynamics of generalised pollination systems across a range of widespread and restricted species.
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Wallenius, Thomas Christopher. "Chemical ecology and pollination biology of the Australian cycad macrozamia communis." Phd thesis, 2014. http://hdl.handle.net/1885/151516.
Full textAbstract:
Cycad pollination typically involves an obligate interaction, in which a specialised insect herbivore feeds, oviposits and pollinates during a short period of cone pollen-shed and receptivity. Two key traits of cycad reproductive biology, cone thermogenesis and emission of volatile organic compounds, are thought to mediate dispersal and colonisation behaviours of the insect pollinators. However, the variation of these two cone traits and the physiological responses of pollinators to them have received little attention. For my PhD thesis, I investigated cone thermogenesis and volatile emission in the Australian cycad Macrozamia communis, and the behavioural and antennal responses of the weevil pollinator Tranes lyterioides. The cone traits and physiological responses of the pollinators were investigated in the context of the two main hypotheses of cycad pollination, brood-site deception and volatile-mediated push-pull pollination. Initial research focused on the interaction between thermogenesis and emission levels of four main volatiles in pollen-shedding male and receptive female cones. A significant positive correlation between daily thermogenic events and volatile emission levels was found in both male and female cones, and coincided with the timing of weevil pollination behaviours, suggesting a role of the two cone traits in pollination. Behavioural responses of T. lyterioides weevils to varying concentrations of the four main volatiles, other volatiles and cone odour were explored using dichotomous-choice bioassays, with results indicating that high concentrations of volatiles may promote dispersal of the weevils from cones. Antennal responses of T. lyterioides weevils to varying concentrations of the four major volatiles and their blends were investigated by means of electroantennography. The results showed determining that male and female weevils exhibit high olfactory sensitivity to these volatile blends. While similarities in the levels of thermogenesis and volatile odour bouquets existed between male and female cones, consistent with brood-site deception, the role of variation in the levels of specific volatiles and pollinator responses to them requires further investigation before this hypothesis is confirmed. The consistent and strong repellence of weevil pollinators by all four main cone volatiles supports the "push" aspect of the "push-pull' pollination hypothesis. However, weevils were not attracted to lower concentrations of volatiles and thus no "pull" was found to be exerted. Thus, the host location of T. lyterioides could not be distinguished from that of any other phytophagous insects. It was concluded that further study and refinement of existing hypotheses is still required to elucidate the intricate coordination between cone traits and behavioural and sensory adaptations of the pollinators before we fully understand the pollination system of M. communis.
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Hoare, Robert James Bruce. "Systematics of Australian Nepticulid moths (Lepidoptera: Nepticulidae)." Phd thesis, 1998. http://hdl.handle.net/1885/145281.
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Purcell, Michaela. "Phylogeny and host relationships of the Australian gall-inducing fly Fergusonina Malloch (Diptera: Fergusoninidae)." Phd thesis, 2017. http://hdl.handle.net/1885/143779.
Full textAbstract:
Fergusoninidae is a monogeneric family of mainly Australian
flies. In a unique obligate mutualism with a nematode, these
flies induce galls on plants in the family Myrtaceae, and have
been recorded on seven genera of host plants, most commonly on
the eucalypts. Most host plants are associated with multiple
species of Fergusonina, usually galling different sites on the
plant. Despite the abundance and diversity of Fergusoninidae and
its tight association with Australia’s most iconic flora, the
host specificity and coevolutionary relationships of Fergusonina
with its plant hosts have not previously been examined in depth.
I used a phylogenetic approach based on mitochondrial COI to
examine the evolutionary relationships between Fergusonina
species and their plant hosts, initially performing a Bayesian
analysis of 41 putative species on flies from Eucalyptus plant
hosts. This analysis revealed well-supported lineages of flies
characterised by larval morphology and gall type, usually from
the same plant host subgenus. The deeper phylogenetic
relationships between groups of species remained unclear, so I
performed a further analysis of an expanded dataset including
flies from four host genera, using separate and concatenated COI
and nuclear CAD sequences.
Having disparate evolutionary time scales, Fergusonina and their
hosts cannot have codiverged early in the history of Myrtaceae,
but current fly-plant host specificity suggested that there may
be cospeciation at finer taxonomic levels. A fine-scale analysis
of
vi
flies collected from a clade of ten Eucalyptus species explored
the plant-fly coevolutionary relationships in three clades of
flies from different sites of the host plant: flower buds, leaf
blades and vegetative shoot buds. The degree of host specificity
displayed by the three fly groups varied markedly, with flower
bud gallers exhibiting the most cophylogenetic history, and leaf
blade gallers the least. These results suggest that host
switching occurred often in the history of Fergusonina and
Myrtaceae.
I compared molecular, morphological and ecological criteria for
determining species limits, including a number of molecular
species delimitation models. Delimiting species using a 2%
pairwise distance was most consistent with other data such as
larval and adult morphology, host and gall site. However,
molecular methods were not adequate to clarify some ambiguous
species limits, highlighting the need to integrate multiple
criteria when identifying species in this group.
Over the course of the study, I discovered around 95 unrecorded
host plant/gall site associations, indicating that the potential
number of species in this family is very large. The definable
morphological and ecological differences among the lineages of
Fergusonina, supported by molecular evidence, argue for a
revision of the genus along these lines. The type species for
Fergusonina, collected in Sydney in 1924, is in poor condition
and is not identifiable; there are no records of its host, gall
type or larval morphology, and I could not extract and DNA from
it. A neotype will need to replace the existing holotype, or the
type species assigned to a probable group. After a comparison of
morphological characters I concluded that the type species is
likely to belong to a group associated with the host genus
Corymbia.
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Reid, Christoper Athol McEwan. "Systematics of the Australian Cryptocephalinae (Coleoptera: Chrysomelidae)." Phd thesis, 1990. http://hdl.handle.net/1885/12539.
Full textAbstract:
The morphology of the larvae, pupae and adults of Camptosomata (Cryptocephalinae and sister-group Lamprosomatinae) is reviewed, with special reference to the Australian fauna. Terminology for the larval structures is redefined and a special study is made of the adult female oviposition structures. The morphological data base is studied with the phylogenetic analysis program PAUP and the variation of characters and taxa examined further with the program MACCLADE. The morphological data and the phylogenetic analyses based on these data are applied to the redefinition of the Camptosomata and constituent taxa using a cladistic methodology. The Camptosomata are redefmed and their possible sister-groups discussed. The Camptosomata are shown to be a monophyletic group and to exclude both Megascelidini (a tribe ofEumolpinae) and Synetinae. The Camptosomata comprise two subfamilies, Lamprosomatinae and Cryptocephalinae. Four tribes of Cryptocephalinae are recognised and redefined. One of these, the Cryptocephalini, with a high proportion of Australian taxa, is divided into five subtribes of 1, 3, 3, 5 and 11 genera. The following nomenclatural changes are proposed (ignoring changes of rank):
Platycolaspina subtribe nov., Coenobiina subtribe nov., Ditropidina subtribe nov. and synonymy of Monachina (a homonym) and Cryptocephalina. New genera or
subgenera proposed are : Semelvillea (in Platycolaspina), Ditropidella (in Ditropidina)and M elatia (in Cryptocephalina), and the subgenera Aorocarpon and Cadnwides in Cadmus Erichson (Cryptocephalina). The following generic synonymy is proposed
(senior synonym first) : Leasia Jacoby(= Agetinella Jacoby); Aprionota Maulik (=
Cephalocryptus Gressitt, Pycnophthalma Maulik); Ditropidus Erichson (= Bucharis
Baly, Elaphodes Suffrian, Euditropidus Lea, Pleonwrphus Chapuis, Polyachus
Chapuis, Prasonotus Suffrian, Tappesia Baly); Scaphodius Chapuis (=Nyetra Baly); Cryptocephalus Geoffroy(= Jaxartiolus Jacobsen andBassareus Haldeman); Aporocera Saunders(= Chariderma Baly, Chloroplisma Saunders, Cyphodera Baly, Loxopleurus Suffrian, Melinobius Jacoby, Rhombosternus Suffrian, Schizosternus Chapuis). New combinations of genera in tribes and subtribes are Mylassa Stal reinstated as a valid genus in Pachybrachini, Platycolaspis Jacoby andLeasia Jacoby in
Cryptocephalini (Platycolaspina) and Arnomus Sharp and Atenesus Weise in
Platycolaspina. As a result of the above new generic synonymy, several new species
combinations are made. The new genus Semelvillea ,with eight species, is mono graphed. Types of three-quarters of the described species of New Zealand and Australian Cryptocephalinae were examined and the following new species synonymy is made (senior synonym first): Chlamisus aterrimus (Lea)(= C. australis Bryant); Arnomus curtipes Broun (=A. impressus Broun, =A. viridicollis Broun); Arnomus signatus · Broun ( = A. fulvus Broun, =A. vicinus Broun); Ditropidus anthracinus Erichsen ( =
D. punctivarius Lea); Ditropidus aurichalceus Suffiian (=D. oblongipennis Lea); Ditropidus carbonarius Baly (=D. subsimilis Lea); Ditropidus festivus (Suffrian) (=D. suffriani Chapuis); Ditropidus maculicollis Chapuis (=D. erythroderes (Lea), =D. niger (Lea), =D. maculicollis (Weise)); Ditropidus ornatus Baly (=D. alphabeticus Lea); Ditropidus pallidipennis Chapuis (=D. dolichognathus (Lea)); Ditropidus
ruficollis Saunders (=D. elegantulus Baly, =D. rufipes Saunders); Ditropidus
saundersi (Baly) (=D. multimaculatus (Lea)); Ditropidus variiceps Lea (=D.
marginipennis Lea); Aporocera albogularis (Chapuis) (=A. coccineus (Chapuis), =A. delicatulus (Lea)); Aporocera apicalis Saunders(= A. bicolor Saunders); Aporocera argentata (Chapuis) (= A.fasciata (Weise)); Aporocera aurantiaca (Chapuis) (=A. monticola (Blackburn)); Aporocera australis (Saunders) (=A. erosa (Saunders), =A.
larinus (Lea)); Aporocera cicatricosa (Chapuis) (=A. calomeloides (Lea)); Aporocera gibba (Chapuis) (=A.lugubris (Lea)); Aporocera iridipennis (Chapuis) (=A. decens
(Weise)); Aporocera libertina (Suffrian) (=A. castor (Lea)); Aporocera nigrolineata (Chapuis) (=A. castigatus (Lea)); Aporocera parenthetica (Suffrian) (=A. melanopa (Lea)); Aporocera paupercula (Germar) (=A. rufescens (Boheman)); Aporocera ring ens (Chapuis) (=A. clypealis (Lea)); Aporocera tasmanica (Saunders) (=A.
impressicollis (Boheman)); Aporocera viridipennis (Saunders)(= A. t-nigrum (Lea));Aporocera viridis (Saunders)(= A. aereus (Suffrian)); Aporocera analis (Chapuis) (= A.foveiventris (Lea)); Cadmus crucicollis (Boisduval) (=C. canaliculatus Chapuis, = C. rugosus Suffrian); Cadmus litigiosus Boheman (=C. vibrans Suffrian); Cadmus cariosus Chapuis (=C. minor (Blackburn)); Cadmus pauxillus Chapuis (=C. perlatus Lea); Cadmus braccatus (Klug) (=C. saundersi Baly); Cadmus breweri(Baly)(= C. duboulai Baly). Representation of Cryptocephalinae in Australia is shown to be as follows (number of genera in brackets) : Chlamisini (1), Clytrini (1), Pachybrachini (1, introduced), Platycolaspina (4), Coenobiina (1), Ditropidina (2) and Cryptocephalina
(4). Larvae and adults of the genera and subgenera in Australia and the south-western Pacific are diagnosed and keys are provided for the identification of these taxa at both life stages. The entire Camptosomatan fauna of Australia and the south-western Pacific is catalogued.
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Muhunthan, Murugappan. "Novel methods of fumigating Australian wildflowers." Thesis, 2003. https://vuir.vu.edu.au/15647/.
Full textAbstract:
For the last ten years, the Australian wildflower export trade has been expanding rapidly and it is expected to continue to do so. Quarantine restrictions imposed by importing countries render insect-free flowers and foliage mandatory. Flower exporters have a number of options, currently fumigating just prior to export is a major one. At present methyl bromide or Pestigas®-Insectigas® (mixtures of pyrethrum in carbon dioxide and dichlorvos in carbon dioxide respectively) combinations are available to exporters. However, methyl bromide will be phased out by the year 2005. On the other hand, combined fumigants are not highly toxic to certain active or developmental stages of a number of insect pests. Hence, a study was conducted to determine an efficacious alternative fumigant or fumigant mixture for the post-harvest disinfestation of
wildflowers that are destined for the export market.
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(9128900), Laura Catherine Doll. "An investigation of genetic variability in Lucilia cuprina and Musca domestica utilizing phylogenetic and population genetic approaches." Thesis, 2020.
Find full textAbstract:
Forensic entomology is a subdiscipline of entomology that involves the use of insect behavior and developmental data to aid in criminal investigations. Genetic data has become increasingly important to the field as there has been a push for DNA-based species identification methods of forensically relevant insects. Genetic data can also elucidate population structure and relatedness of these insects, and such knowledge can contribute to the development of more specific datasets for insects in different regions. The first study presented here investigated the phylogenetics of sister species Lucilia cuprina and Lucilia sericata to identify possible subspecies divisions and issues with DNA-based identifications in the United States. The initial aim of this study was to identify genetic differences between specimens of L. cuprina that preferred live versus carrion flesh. Flies collected from Indiana, USA and South Africa were sequenced and analyzed. Upon sequencing of the genes COI, Period, and 28s, our results indicated that L. cuprina from Indiana possess a unique combination of nuclear and mitochondrial haplotypes that suggest a unique lineage, possibly indicating modern hybridization with L. sericata. The inability of both nuclear and mitochondrial genes to distinguish between L. cuprina and L. sericata raises questions about the capabilities of DNA-based species identifications within this genus. Additionally, the inability of these genes to distinguish between specimens that preferred live versus carrion flesh highlights a need for continued research of these behavioral differences. The second study presented here investigated the population structure and relatedness of house flies in the American southwest in relation to a civil lawsuit where neighbors of a poultry farm alleged that flies were emanating from the farm to their homes. Musca domestica (house fly) specimens were collected from the chicken farm and from locations in varying directions and distances from the farm. Amplified fragment length polymorphism (AFLP) analysis was performed and the data were used in a number of analyses. Population reallocation simulations generally indicated that samples from different locations were not genetically different enough from other locations to allocate to their true origin population over others. Kinship analysis showed differences in samples collected in a later season that indicate a genetic bottleneck over time. Population structure analysis indicated the presence of two intermixing genetic populations in the dataset. AMOVA revealed that the majority of genetic variation laid within, rather than among, populations. A Mantel test revealed no significant correlation between genetic and geographic distances. These results indicate that the M. domestica population in this region of southwestern America is large and intermixing, with no clear genetic distinctions between specimens collected at the poultry farm versus the surrounding locations. In regard to the civil lawsuit, it was not possible to conclude that the flies did not emanate from the poultry farm. In a broader perspective, these data can be utilized to develop pest management strategies in this region. Overall, the data from both studies presented here will be useful to forensic investigations, development of more specific and detailed data and identification techniques, and pest control measures.
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Qin, Ting Kui. "Phylogeny and biogeography of the wax scales (Hemiptera: Coccoidea: Coccidae) with special reference to Ceroplastes sinensis Del Guercio." Phd thesis, 1993. http://hdl.handle.net/1885/140210.
Full text
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Landsberg, Jennifer Jill. "Dieback of rural eucalypts : dietary quality of foliage and insect herbivory." Phd thesis, 1986. http://hdl.handle.net/1885/143177.
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Kamgan-Nkuekam, Gilbert. "Ophiostomatoid fungi and their insect associates on Eucalyptus trees in Australia and South Africa." Thesis, 2011. http://hdl.handle.net/2263/31365.
Full textAbstract:
The eucalypt plantation industry in South Africa is an important source of revenue for the country.
Eucalypt trees have been planted in the country for more than 200 years, as ornamentals, sources of
fuel and construction wood, and more recently also for the production of paper and rayon, amongst
other uses. The planting of eucalypts in South Africa has contributed to the development of many
forestry industries. It has also reduced the logging of indigenous forests. Eucalypts in South Africa
are, however, affected by numerous pests and pathogens. These include native South African pests
and pathogens, as well as those introduced from other countries. Of the pathogens, those commonly
reffered to as pathogenic Ophiostomatoid fungi, particularly species of Ceratocystis and
Ophiostoma are probably the best known. In recent years, some fungal species in the genera
Ceratocystis and Ophiostoma have emerged as important threats to plantation forestry globally and
it is critical to understand these fungi in order to reduce their future impact on eucalypts. In this
dissertation, Ophiostomatoid fungi that infested eucalypt trees in Australia and South Africa, that
were also identified from nitidulid beetles that visit these hosts, were identified using morphology
and DNA sequence data. As a foundation for the studies in the dissertation chapter one provided a
review of the literature pertaining to insects in the Nitidulidae and their association with fungi
including Ceratocystis spp. In chapters two and three, four new taxa, C. tyalla, C. corymbiicola, O.
tasmaniense, O. undulatum as well as four previously known species, C. pirilliformis, Ophiostoma
quercus, O. tsotsi, Pesotum australiae were identified from eucalypts in Australia. The four new
taxa were not pathogenic to E. grandis seedlings in greenhouse inoculation studies. In the last two
chapters, seven Ceratocystis and five Ophiostoma spp. were identified from various Eucalyptus
spp. and including some isolated from nitidulid beetles in South Africa. The Ceratocystis spp.
included two new taxa (C. salinaria, C. decipiens) and five known species, C. eucalypticola, C.
pirilliformis, C. moniliformis, C. oblonga, C. savannae. The Ophiostoma spp. included two new
taxa of the Ophiostoma stenoceras-Sporothrix schenkii species complex (O. candidum, O. fumeum)
and three known species (O. quercus, O. tsotsi, O. tasmaniense). The new taxa of Ceratocystis and
Ophiostoma identified in South Africa were not pathogenic to E. grandis seedlings in a greenhouse
inoculation studies. Most of the fungi identified were encountered on some nitidulid insects, and
four of these fungi where found in both Australia and South Africa. This suggests an
intercontinental movement of Ceratocystis and Ophiostoma, probably mediated by insects, in
particular nitidulid beetles.Thesis (PhD)--University of Pretoria, 2011.
Microbiology and Plant Pathology
Unrestricted
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De, Broekert Peter. "Origin of tertiary inset-valleys and their fills, Kalgoorlie, Western Australia." Phd thesis, 2002. http://hdl.handle.net/1885/10816.
Full textAbstract:
An extensive network of valleys filled with a distinctive sequence of Tertiary clastic
sediments lies buried beneath a Quaternary cover in the Eastern Goldfields region of
southwestern Australia. Apart from being weathered in their upper part, the valley-fill
sediments are excellently preserved and constitute the most comprehensive record of
Cenozoic depositional and erosional events in the region. Locally containing economic
concentrations of gold and uranium and forming important groundwater aquifers, good
access to the valleys and their fills is provided by open-cut mines and drill core.
Formerly referred to as 'palaeochannels', the buried valleys are herein termed 'inset-valleys'
to emphasise their subordinate and entrenched position within the bedrock
surface of another system of much broader and subtly defined 'primary-valleys'.
Within the Kalgoorlie study area, which encompasses the upper to middle reaches of the
Roe inset-valley network, the inset-valleys form a fairly coarse textured, sub-dendritic
pattern with up to eight orders of tributaries. The inset-valleys have a width-depth ratio
of approximately 15, increasing in dimensions with tributary order to a maximum width
and depth of about 1.4 km and 75 m, respectively. Most inset-valleys have a
symmetric, open V -shaped transverse form with rare structural benches and unpaired
terraces forming small steps in the side-walls. In longitudinal section, the insetvalley
network displays a smooth, concave-up profile typical of having been reduced
by a stream system graded to base-level.
Contrary to most previous interpretations, the inset-valleys are temporally and
genetically distinct from the primary-valleys in which they occur. The primary-valleys
were largely formed by prolonged fluvial erosion of the Yilgarn Craton during the
Mesozoic, which contributed to filling of the evolving Bight rift basin between
Australia and Antarctica. The inset-valleys, in contrast, were formed by stream
rejuvenation following epeirogenic uplift of the Yilgarn Craton interior well after the
primary-valleys were established. The cause for epeirogenic uplift of the Yilgarn
Craton remains uncertain, but can be tentatively linked to a change in the horizontal
stress field resulting from a major plate tectonic re-organisation in the late Middle
Eocene (-43 Ma), Climate change and eustatic sea-level fall appear to be incapable of
generating valleys of the dimensions and lateral extent exhibited by the inset-valley
networks in the Easten Goldfields. In any case, both of these allogenic variables were
poorly disposed to fluvial incision during the early Tertiary - the climate being
sufficiently warm and humid to support a thick mesothermal rainforest cover, and the
shoreline being restricted to the continental shelf, over 500 km distant from the upper
reaches of the Roe inset-valley network.
Following formation of the primary-valleys and preceding incision of the inset-valleys,
there occurred a period of limited fluvial activity which facilitated widespread deep
weathering of the Precambrian granitoid and greenstone basement rocks that constitute
the bulk of the eastern Yilgarn Craton. This is evidenced by the weak influence of bedrock lithology and structure on the pattern of inset-valley incision and the chemical
maturity of the inset-valley fills.
In common to all sections of the inset-valley fills examined are three unconformities,
the lowermost of which is the inset-valley form. These provide a convenient framework
for subdividing the inset-valley fills into two alloformations and an overlying sequence
of 'primary-valley fill'. The basal alloformation (AFl), comprises an assemblage of
dominantly coarse-grained, fluvially deposited lithofacies whose composition and
architecture depend strongly on position within the inset-valley network, and for
'tributary' (~5th-order) inset-valleys, also on the type of underlying bedrock. This
allows for the definition of three AFl 'fill-styles'- fill styles I and 2 incorporating the
fill of tributary inset-valleys developed over weathered granite and mafic-ultramafic
rocks, respectively; and fill-style 3 comprising the fill of trunk inset-valleys. All three
fill styles clearly reflect derivation from deeply weathered basement and were deposited
in high gradient, low sinuosity bedload channels that occupied the full width of the
inset-valley floor, or migrated repeatedly across it destroying all evidence of overbank
sedimentation. Channel fills of regularly alternating coarse- and fine-grained strata
indicate that stream discharge was strongly cyclic.
Alloformation 2 (AF2) by contrast, is dominantly composed of clay-rich lithofacies
deposited in a hydrologically fluctuating, wetland environment. Lenses of ferruginous
gravel, sourced from both within and outside the 'basin' of deposition, reflect the
episodic establishment of fluvial conditions. Weathering and diagenetic overprints are
typically extensive, assuming the form of dolomite pods, opaline silica lenses, and
abundant ferruginous nodule and mottle structures.
Deposition of AFl occurred rapidly in response to an excess of sediment supply
affected by a change to a markedly seasonal climate during the middle-late Middle
Eocene. Subsequent marine transgressions during the late Middle-Late Eocene invaded
the lower reaches of the Eastern Goldfields inset- and primary-valley networks, but did
not penetrate for far inland because sediment supply was able to keep pace with the
generation of accommodation space. Instead, within the middle,-upper reaches of the
inset-valley networks, fluvial deposition continued with the influence of a rising baselevel
being transferred upstream as changes in fluvial style.
Closely following the Late Eocene sea~level maximum there occurred a major marine
regression resulting from the first Cenozoic continental-scale glaciation of Antarctica
(Terminal Eocene Event). This rapidly brought the shoreline back to the continental
shelf causing widespread erosion within the inset-valleys and removal of any evidence
of the marine transgressions from the middle-upper reaches of the Roe inset-valley
network.
Low sea-levels and a marked cooling of global climate following the Terminal Eocene
Event saw the development of cool. dry conditions onshore, transforming the inset-valley floors into a series of wetlands. Deposition of AF2 commenced at a very slow rate in the Early Oligocene and may have continued through to the Early Miocene.
Deposition of allofonnations 1 and 2 within the middle-upper reaches of the Roe insetvalley
network was, therefore, dominantly controlled by climate and did not result from
distant rises in sea-level, as is generally thought to be the case.
A second phase of epeirogenic uplift of the Yilgarn Craton occurred in the Middle
Miocene bringing the inset-valley fills to their current elevations. However, owing to
further reductions in rainfall and fluvial activity, erosion associated with this phase of
uplift was slight. Arid to semi-arid conditions prevailed during the Late Miocene-Holocene,
resulting in deposition of the primary-valley fill and completion of the
Cenozoic succession.
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Keshlaf, Marwan M., University of Western Sydney, College of Health and Science, and Centre for Plant and Food Science. "An assessment of honeybee foraging activity and pollination efficacy in Australian Bt cotton." 2008. http://handle.uws.edu.au:8081/1959.7/38265.
Full textAbstract:
Cotton is a high-value commercial crop in Australia. Although cotton is largely self-pollinating, previous researchers have reported that honeybees, Apis mellifera, can assist in cross-pollination and contribute to improved yield. Until recently, use of bees in cotton had, however, been greatly limited by excessive use of pesticides to control arthropod pests. With the widespread use of transgenic (Bt) cotton varieties and the associated reduction in pesticide use, I decided to investigate the role and importance of honeybees in Bt cotton, under Australian conditions. I conducted two major field trials at Narrabri, in the centre of one of Australia’s major cotton-growing areas, in the 2005-6 and 2006-7 seasons. In the first trial, I particularly assessed methods of manipulating honeybee colonies by feeding pollen supplements of pollen/soybean patties, and by restricting pollen influx by the fitting of 30% efficient pollen traps. I aimed to test whether either of these strategies increased honeybee flight activity and, thus, increased foraging on cotton flowers. My results showed that although supplementary feeding increased bee flight activity and brood production, it did not increase pollen collection on cotton. Pollen traps initially reduced flight activity. They also reduced the amount of pollen stored in colonies, slowed down brood rearing activity, and honey production. However, they did not contribute to increased pollen collection in cotton. In the second trial, I spent more time investigating honeybee behaviour in cotton as well as assessing the effect of providing flowering cotton plants with access to honeybees for different time periods (e.g. 25 d, 15 d, 0 d). In this year, I used double the hive stocking rate of (16 colonies / ha) than in the previous year, because in 2005-6 I observed few bees in cotton flowers. I also conducted a preliminary investigation to assess whether there was any gene flow over a 16 m distance from Bt cotton to conventional cotton, in the presence of a relatively high honeybee population. Both of my field experiments showed that honeybees significantly increased cotton yield via increased boll set, mean weight of bolls, number of seeds / boll, and weight of lint / boll. It was obvious that cotton flowers, and particularly cotton pollen, were not attractive to honeybees, and this was also reflected in the low proportion (5.3% w/w) of pollen from cotton collected in the pollen traps. However, flower visitation rate was generally above the 0.5% level regarded as optimal for cross-pollination in cotton, and this was reflected in increased yield parameters. I recorded a gene flow of 1.7 % from Bollgard®II cotton to conventional cotton, over a distance of 16 m. This is much higher than had previously been reported for Australia, and may have been a result of high honeybee numbers in the vicinity, associated with my managed hives. In an attempt to attract more honeybees to cotton flowers, I conducted an investigation where I applied synthetic Queen Mandibular Pheromone (QMP) (Fruit Boost®) at two rates, 50 QEQ and 500 QEQ / ha, and for two applications, 2 d apart. Neither rate of QMP increased the level of bee visitation to flowers, either on the day of application or the subsequent day. There was also no increase in boll set or yield in plants treated with QMP. My observations of honeybee behaviour in cotton brought some interesting findings. First, honeybees totally ignored extra floral nectaries. Second, most flower-visiting honeybees collected nectar, but the overwhelming majority of them (84%) collected floral nectar from outside flowers: this meant these bees did not contribute to pollination. Those nectar gatherers which entered flowers did contribute to pollination. However, they were observed to exhibit rejection of cotton pollen by scraping pollen grains from their body and discarding them, prior to returning to their hives. Pollen gatherers collected only small, loose pellets from cotton. SEM studies showed that cotton pollen grains were the largest of all pollen commonly collected by bees in my investigations, and that they also had large spines. It is likely that these characteristics make cotton pollen unattractive to honeybees. Another possible reason for the unattractiveness of cotton flowers was the presence of pollen beetles, Carpophilus aterrimus, in them. I conducted a series of studies to determine the role of pollen beetles in pollination of cotton. I found that they did not contribute to pollination at low levels; at high populations they damaged flowers (with ≥ 10 beetles / flower, no flowers set bolls); and that honeybees, when given the choice, avoid flowers with pollen beetles. Because the insecticide fipronil was commonly used in Australian cotton at flowering time, and because I had some experience of its toxic effects against honeybees in my field investigations, I conducted a series of laboratory and potted plant bioassays, using young worker bees. The studies confirmed its highly toxic nature. I recorded an acute dermal LD50 of 1.9 ng / bee, and an acute oral LC50 of 0.62 ppm. Fipronil’s residual toxicity also remained high for an extended period in both laboratory and potted plant trials. For example, when applied to cotton leaves in weather-exposed potted cotton plants, it took 25 d and 20 d for full and half recommended rates of fipronil, respectively, to become non- toxic to honeybees. I had previously investigated whether a shorter period of exposure of cotton plants to honeybees would contribute adequately to increased yield, and concluded that a 10 d window within a 25 d flowering period would contribute 55% of the increase in total weight of bolls contributable to honeybee pollination, but only 36% of the increase in weight of lint. Given the highly residual activity of fipronil I recorded, the only opportunity for an insecticide-free period during flowering would be at its commencement. I concluded that, while there is evidence that honeybees can contribute to increased cotton yield in Bt cotton in Australia, this is unlikely with the continued use of fipronil at flowering.Doctor of Philosophy (PhD)
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Kim, Il-Kwon. "Evolution of gall inducing Eulophidae (Hymenoptera: Chalcidoidea) on Myrtaceae in Australia." Phd thesis, 2008. http://hdl.handle.net/1885/110000.
Full textAbstract:
The present thesis consists of two main parts: 1) descriptive works including new
species descriptions and a gall community study and 2) phylogenetic studies. The major
aim is to determine the evolutionary pathway of gall induction biology among
Australian parasitic Tetrastichinae (Hymenoptera: Eulophidae).
The descriptive works include three new gall inducing tetrastichines; Quadrastichus
erythrinae Kim from Erythrina (Fabaceae) as the first gall-former in the genus, Moona
spermophaga Kim and La Salle from seeds of Corymbia (Myrtaceae) and Leprosa
milga Kim and La Salle from seeds of Eucalyptus (Myrtaceae). Also, a new gall
inducing tribe Boucekelimini has been described from Melaleuca (Myrtaceae), and this
new tribe contains two new genera Boucekelimus Kim and La Salle and Tatiana Kim
and La Salle.
A gall community study including species composition, abundances and seasonal
occurrence was conducted. This gall community on Eucalyptus appears very complex in
its species composition and interactions among gall-formers, parasitoids and inquilines.
The wasp community consists of twelve species of five families in two hymenopteran
superfamilies. Two unidentified Ophelimus speices (Eulophidae: Ophelimini) are
dominant species among wasps emerged from the galls. The first Ophelimus species
was found to be a primary gall-former. The second Ophelimus seems to be a parasitoid
or an inquiline of the first Ophelimus. All other associates seem to be parasitoids or inquilines.
Morphological and molecular data were used to infer the evolution of gall induction
biology on Eucalyptus in Australian Tetrastichinae. Also the combined analysis with
both morphological and molecular data was conducted. Each morphological, molecular
and the combined analysis yielded contradicting results.
47 characters from 24 tetrastichine species and two outgroup species were used for the
morphological analysis. Cladograms were constructed, and the results were compared
with Graham's suggestion (1987) about relationships among the tetrastichine genus
groups. His suggestion was largely contradicted by the present analyses. The analyses
suggested that both the Aprostocetus-complex and the Tetrastichus s. str. are nonmonophyletic.
However, some group clustering appeared to fit relatively well with
Graham's suggestion: Aprostocetus + Neotrichoporoides, Crataepus + Pronotalia, and
the separation of the Australian gall inducing group from the European fauna.
The barcoding region (619 bps fragment) of Cytochrome Oxidase subunit I (COI) on
the mitochondrial gene was sequenced from 25 tetrastichines as ingroup and one
outgroup species. The Barcode gene failed to resolve phylogeny at genus level but is
very useful for identification of species in a genus or cryptic species. Molecular
analyses found that the Leptocybe species group consists of seven unique sequences.
Two species in this species group drew my attention: Leptocybe invasa Fisher and La
Salle, which is a devastating invasive pest in Israel, and Leptocybe sp. 9, which was most recently found in Australia. They were thought to be the same species due to the
same biology and gall type. However, the molecular analyses suggest that Leptocybe sp.
9 is not L. invasa but a very close species.
The evolution of gall induction on Eucalyptus among Australian Tetrastichinae was
estimated from the morphological and molecular data. Overall, the morphological
analysis suggests two independent origins of gall induction on Myrtaceae in
Tetrastichinae while the combined analysis only one origin. Also, the results of the
analyses suggest that gall inducing lineages may have evolved from a parasitic
progenitor and the ancestral stock of the Australian gall-inducers may have first induced
galls on seeds of Eucalyptus. Leaf galling and leaf & twig galling genera except
Epichrysocharis may have evolved deep within the seed-galling lineage.
46
Hosseini, Reza. "A DNA-based approach to study predator-prey trophic interactions within Brassica crops : a search for predators of diamondback moth (Plutella xylostella)." 2007. http://hdl.handle.net/2440/56816.
Full textAbstract:
Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library.Brassica vegetables and oilseeds are economically important crops worldwide. These crops are associated with several destructive and widespread insect pests. In Australia these pests include six species, Plutella xylostella (Linnaeus), Pieris rapae (Linnaeus), Hellula hydralis Guenée, Helicoverpa punctigera (Wallengren), Brevicoryne brassicae (Linnaeus) and Myzus persicae (Sulzer), which are the focus of this research. Among them P. xylostella (diamondback moth or DBM) is the most serious and destructive insect pest. Little is known about the potential of predators, which may be able to contribute to control diamondback moth, although some field studies have shown the overall importance of predators in controlling this key pest. The aim of this study was to develop a method that allows study of predator-prey trophic interactions in the field.
http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1294814
Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2007
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"Scale insect infestation of phragmites australis in the Mississippi River delta, USA: Do fungal microbiomes play a role?" Tulane University, 2020.
Find full text
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Vezvaei, Ali. "Pollination studies in almond / by Ali Vezvaei." Thesis, 1994. http://hdl.handle.net/2440/18503.
Full text
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Rozario, Shelley Anastacia. "Population ecology of leafhoppers (Hemiptera: Eurymelidae) on eucalypts and their associations with ants." Master's thesis, 1989. http://hdl.handle.net/1885/142284.
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Weichel, Nyree. "Acacia victoriae and its association with sugary-exudate producing herbivorous insects and trailing dominant ants in semi-arid Australia." Thesis, 2012. http://hdl.handle.net/2440/80456.
Full textAbstract:
Associations between ants, sap-sucking herbivores, and plants are often mutualistic, but abiotic and biotic conditions can change the magnitude of costs and benefits to partners. This is sometimes sufficient to tip the outcome for at least one partner to neutral or negative. Little is understood about this conditionality of outcomes. Other arthropods on the plants are likely to affect outcomes for partners, but little is known about broader effects of these associations on the arthropod community. Consistent differences in environmental conditions might bring about differences in function of these associations, so there may be a tendency for outcomes for partners to depend on biome, for which there is some evidence. Associations where plants provide sugary exudate (SE) to ants either directly or through supporting populations of herbivorous insects are widespread and common in Australia on the two most common genera Acacia and Eucalyptus, yet very few studies of this have been done. Due to the unique suite of environmental conditions on the Austral continent such as the prevalence of aridity, these types of associations may be particularly adaptive for woody plants. Acacia victoriae is the second most widespread acacia in Australia. A membracid of a genus which is widely distributed across Australia, Sextius sp., frequently colonizes it in semi-arid southern Australia, as do various Margarodidae and lycaenid larvae. Very aggressive dominant small black ants of the genus Iridomyrmex (SBIs) trail among the shrubs to attend these sugary-exudate producing herbivores (SEPHs) on them. Spatial distribution of association partners can provide clues not only to likely effects partners have on each other but to how the associations might affect other sectors of the natural community. On gridded sites, A. victoriae shrubs, SEPHs on them, and nests of SBIs were mapped and their spatial distribution analysed. A field experiment and field survey examined effects of different densities of SEPHs/Sextius sp. on A. victoriae growth and reproductive success and associated arthropod assemblages and investigated factors determining densities of SEPHs on the shrubs. The field survey also examined effects of slope-aspect, as an aridity gradient, on soil parameters, shrub growth and reproductive success, SEPHs attended by Iridomyrmex, and other arthropods on shrubs. The study found that A. victoriae clustering on sites decreased with size of shrub, and SEPH populations were positively associated with SBI populations both on individual shrubs and at the scale of 15 m x 15 m. SEPH/Sextius presence on A. victoriae depended on SBI presence, and SBI numbers on stems depended on SEPH numbers more than on stem size. Sextius density was linked to nutrient levels of soil near shrubs and shrub leaves and to shrub growth rate. A. victoriae growth rate was in turn reduced by exclusion of Sextius on stems, and on shrubs with naturally high SEPH/Sextius densities, growth and seed production was higher, folivory was lower, and assemblages of small arthropods were different. Parasitoid wasp densities were strongly affected by SEPH/Sextius densities and there was some evidence that wasp densities regulated SEPH/Sextius densities in turn. Indeed, parasitoid wasps and SEPH/Sextius may strongly regulate densities of each other and through that regulate densities of other small arthropods on the shrubs. Dynamics of both potentially influential insect groups may be affected by rainfall and insolation. Slope-aspect affected most parameters considered. Results were consistent with the possibility of favourability of semi-arid conditions for the shrub-SEPH-SBI interaction. This study is the first to investigate the association between these taxa and warrants further research into the dynamics of the association, favourability for the association of arid conditions, and how the association affects the broader community.Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2012