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1

Beilharz, Vyrna Caldwell. "Cercosporoid fungi on Australian native plants /." Connect to thesis, 1994. http://eprints.unimelb.edu.au/archive/00000670.

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2

Reichman, Suzanne Maree. "Responses of Australian native plants to metal toxicity /." St. Lucia, Qld, 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16424.pdf.

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3

Negahban, Marzieh. "The medicinal effects of two Australian native plants." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/206455/1/Marzieh_Negahban_Thesis.pdf.

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Chronic wounds are a costly and growing problem to global health care systems and affect the productivity of patients and their quality of life. In all cultures, people have used medicinal plants for the treatment and alleviation of various health issues. This project has shown a new potential role for the primary extracts and isolated compounds of C. terminalis derived-kino and the primary extracts of H. tiliaceus (L.) leaves as wound healing agents in vitro, and hence, potentially paves the way for future novel therapeutics for the treatment of chronic non-healing wounds.
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4

Schuurmans, Julia. "Evidence for Heavy Metal Accumulation in Native Australian Plants." Thesis, Curtin University, 2021. http://hdl.handle.net/20.500.11937/85770.

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This study investigated the accumulation of toxic heavy metals in native vegetation when grown on mine tailings and determined potential exposure pathways to animals and humans. Analytical chemistry techniques were employed by using spectroscopy and electrochemistry to determine heavy metal quantities in plants, soil and water, which was able to determine the persistence of heavy metals in soil and that plants were bioaccumulating higher concentrations of heavy metals when grown in or nearby mine tailings.
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5

Sirdaarta, Joseph P. "Phytochemical Study and Anticancer Potential of High Antioxidant Australian Native Plants." Thesis, Griffith University, 2016. http://hdl.handle.net/10072/365567.

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High antioxidant capacities have been linked with a reduction in the incidence of chronic diseases including cardiovascular disease, diabetes, obesity, neurodegeneration, inflammation and cancer. Furthermore, phenolic antioxidants may not only have protective effects against these diseases, but may also have therapeutic potential in reversing them by modulation of the cellular redox state. Thus, plants with high antioxidant capacities have potential in the development of new chemotherapeutic treatments to prevent and treat some cancers. Several native Australian plant species including Terminalia ferdinandiana Exell (Kakadu plum), Tasmannia lanceolata (Poir.) A.C.Sm., (Tasmannian pepper), Syzygium australe (H.L.Wendl. ex Link) B.Hyland (brush cherry), Syzygium luehmannii (F.Muell.) L.A.S.Johnson (riberry), Davidsonia pruriens F.Muell. (Davidson’s plum), Elaeocarpus angustifolius Blume (quandong), Kunzea pomifera F.Muell. (muntries), Podocarpus elatus R.Br.ex Endl., (Illawarra plum) and Acronychia acidula F.Muell., (lemon aspen) have recently been reported to have extraordinarily high antioxidant content and were therefore selected to screen for the ability to inhibit proliferation of selected carcinoma cell lines.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Natural Sciences
Science, Environment, Engineering and Technology
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6

Tarrant, Valerie M., and valerie tarrant@deakin edu au. "Melbourne's indigenous plants movement: The return of the natives." Deakin University. School of History, Heritage and Society, 2005. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20061207.113857.

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This thesis examines Greater Melbourne’s indigenous plants movement from the 1930s to the early twenty first century. It demonstrates the important scientific and educational role of the public intellectual, Professor John Turner, and of the Melbourne University Botany School which he led for thirty five years. The case study of the movement within the City of Sandringham and its successor the City of Bayside reveals how the inhabitants of an urbanised are responded to threats to the indigenous trees and wildflowers of their neighbourhood, stimulating botanists to assist them and using political means in order to achieve their conservation objectives. The thesis draws upon a range of local archives, conservation literature and private papers.
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7

Jahirul, Md Islam. "Experimental and statistical investigation of Australian native plants for second-generation biodiesel production." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/83778/9/Jahirul_Islam_Thesis.pdf.

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This work explores the potential of Australian native plants as a source of second-generation biodiesel for internal combustion engines application. Biodiesels were evaluated from a number of non-edible oil seeds which are grow naturally in Queensland, Australia. The quality of the produced biodiesels has been investigated by several experimental and numerical methods. The research methodology and numerical model developed in this study can be used for a broad range of biodiesel feedstocks and for the future development of renewable native biodiesel in Australia.
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8

Perera, Muthukuttige. "Phytochemical analysis of two Australian native plants and their effects on chronic wound healing." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/229994/1/Muthukuttige%20Madusha%20Nuwanthi_Perera_Thesis.pdf.

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Chronic wounds are a significant burden to national health services worldwide and a potential reason for patients’ declining quality of life. As such, this project focused on assessing the therapeutic effect of two Australian native plants, Alocasia macrorrhizos and Syncarpia hillii for their potential in chronic wound healing, through investigating their antibacterial, anti-inflammatory, and regenerative properties.
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9

Gibson, Michelle Rene. "Invasive Australian acacias : reproductive biology and effects on native plant-pollinator communities in Cape fynbos." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20399.

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Thesis (MSc)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: My master’s research combines aspects of pollination biology and invasion biology to explore the invasive predictors and impacts of a globally invasive group of plants – Australian acacias. Specifically, I investigate the role of reproductive biology in their invasion success (Chapter 2), the impacts of a specific species, Acacia saligna, on native plant-pollinator communities in South Africa (Chapter 3), and if the impact of A. saligna on native plant species can be predicted, based on floral trait similarity (Chapter 4). Australian acacias possess many floral traits implicated in plant invasion success, including extensive, dense floral displays, prolific seed production, long-lived seed banks, and propensity for vegetative reproduction. In Chapter 2 of my thesis, co-authors and I investigate if such reproductive traits influence whether or not a species becomes invasive once it is introduced by qualitatively and quantitatively analyzing literature and data collected from published and unpublished data. We found that invasive species reach reproductive maturity earlier and are more commonly able to resprout. Our findings have important implications for management of existing Acacia invasions as well as the assessment and prevention of further introductions of Acacia species leading to invasion. Impacts of invasive plant species on native plant visitation and consequent reproduction are often negative and have important implications for future ecosystem health. Acacia saligna is a problematic woody invasive shrub in many Mediterranean regions, and in South Africa, it invades fynbos vegetation, which boasts one of the highest plant diversities per area in the world as well as many specialized pollination mutualisms. It blooms during the flowering peak of most native species and forms dense, showy floral displays, thus the possibility of pollinator-mediated interactions with co-flowering native species is high. In Chapter 3, I assess the impact of flowering A. saligna on insect visitation to co-flowering native species by conducting flower observations at both an invaded and uninvaded (control) site. One of the native species most-visited by native honeybees, Roepera fulva, had high flower visitor overlap with A. saligna and suffered significantly lower visitation from all insects and from bees when A. saligna was present than at the control site. The native honeybee appears to be the most important visitor to A. saligna as it was the most frequent and mobile. Due to its foraging efficiency and dominance in pollinator communities, Apis mellifera subsp. capensis could be an important mediator of the negative effect of A. saligna on co-flowering natives, especially those frequently visited by honeybees. The use of floral traits as predictors of a species’ effect on co-flowering plants via pollination is commonly used in pollination biology. In the fourth chapter of my thesis, I apply the predictive principle of floral traits on flower visitation to see if floral traits can predict the impact of an invasive plant species on co-flowering native species, and if so, which floral traits are the most important. Following the same flower observation protocol as Chapter 3, I assess two measures of invasion impact on native flowers – change in visitation rate to native plant species between invaded and uninvaded sites and flower visitor overlap between A. saligna and native species – and test for a correlation with floral trait similarity of native species to and A. saligna. Similarity of categorical traits and all traits combined (categorical and continuous) were significantly positively correlated with flower visitor overlap, indicating that native species with categorical traits similar to A. saligna were more likely to share flower visitors with A. saligna. Floral symmetry and shape similarity were the most important categorical traits in driving flower visitor overlap. Findings suggest an important link between categorical floral traits and ability to predict invasive plant impact on native flower-insect interactions; however, more comprehensive studies are required for conclusive results.
AFRIKAANSE OPSOMMING: My Meestersgraad se navorsing kombineer aspekte van bestuiwingsbiologie en indringerbiologie om ondersoek in te stel na die indringing-voorspelbaarheid en die impak van Australiese Akasias, 'n wêreldwye indringende groep van plante. Ek het spesifiek gekyk na die rol van voortplantingsbiologie in hul indringing sukses (Hoofstuk 2), die impak van 'n spesifieke spesie, Acacia saligna, op die inheemse plant-bestuiwer gemeenskappe in Suid-Afrika (Hoofstuk 3), en of die impak van Acacia saligna op inheemse plantspesies voorspel kan word, gebaseer is op die ooreenkomste in blomeienskappe (Hoofstuk 4). Australiese Akasias het baie voortplantingseienskappe wat geassisioeer word met plantindringing sukses, insluitend ‘n uitgebreide, digte blommedrag, uitermatige hoë saadproduksie, langlewende saadbank, en die geneigdheid vir vegetatiewe voortplanting. In hoofstuk 2 van my tesis, ondersoek ek en my medeskrywers of sulke voortplantingseienskappe beïnvloed of 'n spesie ‘n indringer raak, deur 'n ontleding van die literatuur en data wat versamel is uit gepubliseerde en ongepubliseerde data. Ons het gevind dat indringerspesies geslagsrypheid vroeër bereik en meer algemeen in staat is om weer uit te loop. Ons bevindinge het belangrike implikasies vir die bestuur van die bestaande Akasiastande sowel as die evaluering en die voorkoming van verdere vestiging van Akasia spesies wat lei tot indringers. Impakte van uitheemse plantspesies op inheemse plant-besoeke deur bestuiwers, en gevolglike voortplanting is dikwels negatief en het belangrike implikasies vir die toekomstige ekosisteem gesondheid. Acacia saligna is 'n problematiese houtagtige indringende struik in baie Mediterreense streke, en in Suid-Afrika. Dit dring in die Fynbos in, wat spog met een van die wêreld se hoogste plant diversiteit per oppervlak, sowel as baie gespesialiseerde bestuiwing-mutualismes. Dit blom gedurende die bloeiseisoen van die meeste inheemse spesies en vorm digte, pronkerige blomuitstallings, dus is die moontlikheid hoog vir bestuiwer-gemedieerde interaksies met inheemse spesies wat saam blom. In Hoofstuk 3, het ek die impak van Acacia saligna, op insek besoeke aan saamblommende inheemse spesies bepaal, deur waarnemings op beide ingedringde en natuurlike studie gebiede. Een van die inheemse spesies, Roepera fulva, wat die meeste besoek is deur inheemse heuningbye, het 'n hoë blom besoeker oorvleueling met Acacia saligna en het aansienlik minder besoeke van alle insekte en van bye gekry toe Acacia saligna teenwoordig was as by die natuurlike studie gebied. Die inheemse heuningby, Apis mellifera subsp. capensis, blyk die mees belangrikste besoeker aan Acacia saligna te wees aangesien dit die mees gereeldste en beweeglikste was. As gevolg van sy oorheersing in bestuiwer gemeenskappe, is die by 'n belangrike faktor van die negatiewe uitwerking van Acacia saligna op die inheemse plante wat dieselfde tyd blom, veral dié wat gereeld besoek word deur heuningbye. Die gebruik van blomeienskappe as voorspellers van 'n spesie se effek op saamblommende plante deur middel van bestuiwing, word algemeen gebruik in bestuiwingsbiologie. In die vierde hoofstuk van my tesis, het ek die voorspellende beginsel van die blomeienskappe op blombesoeking toegepas, om te sien of blomeienskappe die impak van 'n uitheemse plantspesie kan voorspel op saamblommende inheemse spesies, en indien wel, watter blomeienskappe die belangrikste is. Deur dieselfde blom waarneming protokol as in Hoofstuk 3 te gebruik, het ek twee maatstawwe van indringings impakte op inheemse blomme vergelyk - verandering in besoek gereeldheid aan inheemse plante tussen ingedringde en natuurlike studie gebiede en blom besoeker oorvleueling tussen die Acacia saligna en inheemse spesies – en die toets vir 'n korrelasie van blomeienskap ooreenkomste in inheemse spesies en Acacia saligna. Soortgelykheid van kategoriese eienskappe en al die eienskappe gekombineer (kategoriese en deurlopende) is beduidend positief gekorreleerd met blombesoeker oorvleueling, wat aandui dat inheemse spesies met kategoriese eienskappe soortgelyk aan Acacia saligna meer geneig was om blom besoekers te deel met Acacia saligna. Blom simmetrie en vorm ooreenkoms was die belangrikste kategoriese eienskappe wat ly tot blombesoeker oorvleueling. Bevindinge dui op 'n belangrike skakel tussen die die kategoriese blomeienskappe en die vermoë om indringerplant impakte op inheemse blom-insek interaksies te voorspel, alhoewel, meer omvattende studies nog nodig is.
DST-NRF Centre of Excellence for Invasion Biology and the Department of Botany and Zoology at Stellenbosch University for research funding
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10

Gikaara, Daniel Maina. "Phosphorus nutrition of the Australian native flowering plants caustis blakei, sticherus flabellatus and chamelauchium uncinatum /." St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17488.pdf.

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11

Tamuli, Roktima. "Chemical Investigation of Clerodendrum polycephalum for Anti-Malarial Compounds and its Chemical Diversity with Australian Clerodendrum." Thesis, Griffith University, 2022. http://hdl.handle.net/10072/414921.

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The use of indigenous plants by native healers has been in healthcare system for a long time. It is prevalent in many developing countries because of its wide benefits and rising popularity. But less is known about the chemistry behind the medicinal properties of those indigenous plants. Unraveling the knowledge helps develop drugs based on the indigenous plants and understand their mechanisms of the action. Malaria happens to be a vector borne protozoan parasitic disease which has been reported to affect 229 million people in 2019. Use of indigenous plant for treating malaria is widely practiced and this had led to the development of two anti-malarial drugs, artemisinin, and quinine. Clerodendrum polycephalum, also known as ‘egungun eja’ or ‘ewe agbosa’ or ‘aporo’ by different tribes of Nigeria, is used by native healers as an anti-malarial treatment. However, the anti-malarial effect is not well studied and the chemical compounds responsible for its activity is unknown. The understanding of the chemical composition and their antimalarial activities will provide scientific evidence for its traditional application in malaria treatment. This project was a collaborative research between A/Prof Yunjiang Feng at Griffith Institute for Drug Discovery and Prof. Francis B. Adewoyin at Drug Research and Production Unit, Obafemi Awolowo University, and Prof. Alexander B. Odaibo at Department of Zoology, University of Ibadan; mediated by BIO Ventures for Global Health (BVGH). The Nigerian group analysed the crude extract of Clerodendrum polycephalum based on its traditional use; but lack of expertise in natural product chemistry led to this collaboration. The overall objective was to use bioassay as a guide to isolate antimalarial natural products against Plasmodium falciparum 3D7 drug resistant cell lines. Any novel/new compounds will also be targeted by using 1H NMR guided isolation strategy. Knowing the wide distribution of Clerodendrum around the world, several Australian Clerodendrum sp. were investigated by LC-MS to understand the chemical compositions of samples from different geographic locations. The thesis was started with an introduction chapter which included different concepts such as traditional medicine, malaria, Clerodendrum, bioassay guided fractionation, NMR guided isolation and a brief outline of the project. Traditional medicine (TM) was introduced with a detailed description on African traditional medicine (ATM). It then proceeded with a brief discussion on malaria, its causes, and the current treatment. The chapter then provided a detailed description of genus Clerodendrum, its geographical distribution, traditional use and the biological activity of the plant extract and secondary metabolites. The chapter continued with a brief of bioassay guided fractionation. Finally, the chapter ended with a description of NMR guided isolation of compounds with biological activity. Chapter 2 described detailed experimental procedures involved in this project, including isolation and purification of natural products from the plant species. The chapter also detailed the biological assays as well as the spectroscopic data of the pure compounds. Chapter 3 started with an introduction of Clerodendrum polycephalum, then moved on to the bioassay guided isolation which resulted in four pure compounds, including the new clerodane diterpene lactone A. Considering the difficulties in the isolation process due to the presence of large amount of methyl pheophorbide a, the next batch of crude extract was purified using a revised strategy where the fractionation procedure was modified and 1H NMR was utilized to guide the isolation. This resulted in ten compounds, including four new clerodane diterpene lactone (A-D), one new 12,16-Epoxy-11,14,17-trihydroxy-17(15→16)-abeo- 5,8,11,13,15-abietapentaen-7-one, as well as 5 known compounds, namely, acacetin, methyl pheophorbide a, loliolide, bis (2-ethylhexyl) phthalate and 12,16-Epoxy-6,11,14,17- tetrahydroxy-17(15→16)-abeo-5,8,11,13,15-abietapentaen-7-one. The chemical structures were elucidated by comprehensive analysis of 1D-, 2D-NMR and MS spectroscopic data assisted by density functional theory (DFT) calculated NMR and circular dichroism (CD). The in-vitro activity evaluation against P. falciparum 3D7 revealed that methyl pheophorbide a was active with IC50 values of 4.49 M. The compound showed no cytotoxicity against neonatal foreskin fibroblast (NFF) mammalian cells. Our results provided scientific evidence for the traditional use of Clerodendrum polycephalum in malarial treatment. Chapter 4 aims to investigate whether Clerodendrum sp. collected from different geographic location contain similar chemistry. The chapter started with an introduction of Australian Clerodendrum sp., Griffith University’s NatureBank and the use of LC-MS for screening compounds in plant extracts. Fifteen Australian Clerodendrum were extracted and analyzed by LC-MS. Our results suggested that every compound isolated from Clerodendrum polycephalum was detected in the Australian species. Large scale isolation of Nature Bank sample NB020858 yielded verbascoside, diosmetin-5-o-glucuronide, 4-hydroxywogonin-5-oglucuronide and acacetin-5-o-8-hydroxyglucuronide; among these four compounds verbascoside and an analogue of acacetin-5-o-8-hydroxyglucuronide were also detected in the Nigerian plant extract. Based on the results, we conclude that Clerodendrum plant species from Nigeria and Australia contained same classes of compounds, and chemistry can be used as a tool for plant taxonomic identification.
Thesis (Masters)
Master of Science (MSc)
School of Environment and Sc
Science, Environment, Engineering and Technology
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12

Manirujjaman. "Identification of bioactive compounds in native plants and their effects on wound healing." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/132475/1/Manirujjaman_Manirujjaman_Thesis.pdf.

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This project has made an important contribution towards understanding the medicinal potential of three Australian plants. The identification of novel and previously isolated wound healing compounds from the methanolic extracts of the target plants demonstrate that Australian natives are a rich source of bioactive constituents, which may have a therapeutic role for the future treatment of chronic non-healing wounds.
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13

Agampodi, Vajira Asela. "Isolation, identification and evaluation of bioactive compounds in Australian and Sri Lankan native plants and their potential implications for wound healing." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/200345/1/Vajira%20Asela_Agampodi_Thesis.pdf.

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In this project, the therapeutic effects of two medicinal plants were assessed for their potential in treatment of chronic wounds. Currently, chronic wounds impose a heavy socio-economic burden on healthcare systems and societies world-wide. As such, the antibacterial, anti-inflammatory effects and human skin cell regenerative properties of the plant extracts and their isolated bio-active compounds, inflicts high potential to develop novel therapeutics for the treatment of chronic wounds.
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14

Martyn, Amelia. "The physiology and control of bract browning in waratahs (Telopea spp.)." Faculty of Agriculture, Food and Natural Resources, 2005. http://hdl.handle.net/2123/5773.

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PhD
The waratah, Telopea speciosissma and its hybrids with other Telopea species, is an Australian native species grown for domestic and export cut flower markets. The showy floral bracts surrounding the inflorescence often suffer from bract browning, reducing the market value and export potential of the blooms. Prior to this project, the physiological cause of the disorder was not known, although bract browning had been attributed to water stress, heat stress, high light (particularly after frost), wind and mechanical damage. Bract browning was reportedly minimised when waratahs were grown in shaded conditions, although the reduction in browning by shade had not been quantified. The aim of this project was to examine the physiological cause of the bract browning disorder and investigate methods for control. The appearance, timing, and severity of the bract browning disorder was initially characterised by dissecting waratah buds from commercial growers throughout NSW. Bract browning became evident in the six to eight weeks prior to harvest, coinciding with rapid bract and flower expansion. A survey of commercial waratah growers, initiated by NSW Agriculture and the Waratah Industry Network and analysed by the author, corroborated these results. The survey showed that bract browning was observed in all years between 1999 and 2003, with relatively high severity (scores from three to five out of a possible five) in three of those years. Scores or counts of brown bracts were used to assess the severity of the disorder, the latter including the number of senesced floral bracts following browning as a measure of browning severity. The position and timing of browning suggest light damage or localised calcium deficiency could play a role in the development of browning. The bract browning disorder was studied in further experiments on potted red waratahs of cultivars ‘Fire and Brimstone’, ‘Olympic Flame’ and ‘Sunflare’ at the Mount Annan Botanic Garden; on commercially grown ‘Wirrimbirra White’ waratahs at Jervis Bay; and on natural populations in the Royal National Park. The effect of calcium nutrition on bract browning was studied at Mount Annan in 2001 and 2002, testing the hypothesis that browning may be caused by a localised calcium deficiency similar to lettuce tipburn or poinsettia bract necrosis. Waratah bracts had significantly less calcium in all fractions than leaves, with the procedure of Ferguson et al. (1980) used to separate physiologically active, oxalate associated and residual calcium. Calcium chloride sprays applied to developing bracts increased total bract calcium by about 25% in ‘Sunflare’ and ‘Olympic Flame’ cultivars, but not in ‘Fire and Brimstone’. However, application of calcium as a spray to the developing bracts, or as gypsum to the potting medium did not significantly reduce bract browning scores. These results and the development of bract browning in exposed, rather than enclosed tissue, suggest that factors other than calcium are involved in the development of bract browning. The light environment (full sun or 50% shade cloth) had a greater effect than irrigation frequency on bract browning of ‘Sunflare’ and ‘Olympic Flame’ waratahs in 2001. Waratahs grown under 50% shade cloth showed less bract browning at flower maturity than waratahs grown in full sun. This result was corroborated by subsequent experiments in 2002 and 2003. For example, in 2002, shade cloth reduced browning and bract loss by 30-60% at flower maturity, compared to waratahs grown in full sun. Shading waratahs from bud initiation in late summer (December-January) or bud opening in late winter (July-August) was equally effective in reducing browning. Shade cloth (50%) significantly reduced the light intensity experienced by waratah plants throughout the day, as well as reducing the daily maximum temperature and minimum relative humidity. Natural shade conditions at the Royal National Park effectively prevented browning of floral bracts, although the smaller basal bracts still turned brown and senesced. The development of bract browning as waratahs matured was linked to the development of chronic photoinhibition, measured as a decrease in predawn photosynthetic efficiency using chlorophyll fluorescence techniques. Waratah bracts were unable to maintain efficient photosynthesis in full sun conditions and reached saturation of non-photochemical quenching at lower light intensities than leaves. This suggests that bract tissue is adapted to a lower light environment than leaf tissue. Outer bracts had a significantly lower photosynthetic efficiency (Fv/Fm) than leaves early in flower development, as they were exposed to the environment for a prolonged period. Outer bracts also began to senesce towards flower maturity, particularly in full sun, increasing their susceptibility to damage. Inner waratah bracts were able to maintain a high photosynthetic efficiency prior to exposure, but photosynthetic efficiency decreased significantly at the intermediate stage of floral development, as inner bracts were no longer protected by outer bracts. Waratah leaves were more resilient than bracts, and did not suffer from chronic photoinhibition or browning during flower development. The increased susceptibility of bracts to photoinhibition and browning parallels results in other species, such as Dendrobium, where floral tissue experiences photoinhibition, bleaching and necrosis at lower light intensities than leaf tissue. Bracts on shaded waratahs maintained higher chlorophyll, carotenoid and anthocyanin concentrations than sun-exposed bracts, giving more intense flower colour and higher quality blooms. The significant decrease in bract pigmentation in the sun is likely to be a result of pigment destruction following photoinhibition, and has been noted in susceptible tissues of other species, such as Illicium (star anise) leaves. The presence of anthocyanins did not reduce bract browning in waratahs, with the concentration of UV-absorbing compounds showing a stronger positive correlation with protection from photoinhibition than the concentration of anthocyanins. However, anthocyanin concentrations were significantly lower in sun-exposed bracts, and brown compounds appeared to replace anthocyanins in the epidermal cells of brown bracts. Thus, it seems likely that browning in waratah bracts is the visible manifestation of oxidative damage to cell components, following chronic photoinhibition. Light-induced oxidative damage can lead to yellowing and pigment bleaching, lipid peroxidation, the development of necrotic lesions and senescence. However, lipid peroxidation as measured by the malionaldehyde assay gave no indication of oxidative damage to waratah bract tissue. This was probably due to the presence of anthocyanins and other flavonoids and sugars other than sucrose in bract tissue interfering with the colourimetric measurement of thiobarbituric acid reactive substances. The extensive planting of waratahs in NSW in the last five years suggests that the total value of lost production due to bract browning is likely to increase in the future. The browning disorder may also prevent the establishment of waratahs in other markets, as international cut-flower markets demand high quality blooms free from blemishes. The results of this study show that bract browning, photoinhibition and pigment loss are minimised by protecting waratahs from high light intensities from bud opening until harvest. However, the consequences of shading waratahs throughout the year require further investigation, as does the use of different percentages of shade cloth or other methods to reduce incident light.
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15

Martyn, Amelia. "The physiology and control of bract browning in waratahs (Telopea spp.)." Thesis, The University of Sydney, 2004. http://hdl.handle.net/2123/5773.

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The waratah, Telopea speciosissma and its hybrids with other Telopea species, is an Australian native species grown for domestic and export cut flower markets. The showy floral bracts surrounding the inflorescence often suffer from bract browning, reducing the market value and export potential of the blooms. Prior to this project, the physiological cause of the disorder was not known, although bract browning had been attributed to water stress, heat stress, high light (particularly after frost), wind and mechanical damage. Bract browning was reportedly minimised when waratahs were grown in shaded conditions, although the reduction in browning by shade had not been quantified. The aim of this project was to examine the physiological cause of the bract browning disorder and investigate methods for control. The appearance, timing, and severity of the bract browning disorder was initially characterised by dissecting waratah buds from commercial growers throughout NSW. Bract browning became evident in the six to eight weeks prior to harvest, coinciding with rapid bract and flower expansion. A survey of commercial waratah growers, initiated by NSW Agriculture and the Waratah Industry Network and analysed by the author, corroborated these results. The survey showed that bract browning was observed in all years between 1999 and 2003, with relatively high severity (scores from three to five out of a possible five) in three of those years. Scores or counts of brown bracts were used to assess the severity of the disorder, the latter including the number of senesced floral bracts following browning as a measure of browning severity. The position and timing of browning suggest light damage or localised calcium deficiency could play a role in the development of browning. The bract browning disorder was studied in further experiments on potted red waratahs of cultivars ‘Fire and Brimstone’, ‘Olympic Flame’ and ‘Sunflare’ at the Mount Annan Botanic Garden; on commercially grown ‘Wirrimbirra White’ waratahs at Jervis Bay; and on natural populations in the Royal National Park. The effect of calcium nutrition on bract browning was studied at Mount Annan in 2001 and 2002, testing the hypothesis that browning may be caused by a localised calcium deficiency similar to lettuce tipburn or poinsettia bract necrosis. Waratah bracts had significantly less calcium in all fractions than leaves, with the procedure of Ferguson et al. (1980) used to separate physiologically active, oxalate associated and residual calcium. Calcium chloride sprays applied to developing bracts increased total bract calcium by about 25% in ‘Sunflare’ and ‘Olympic Flame’ cultivars, but not in ‘Fire and Brimstone’. However, application of calcium as a spray to the developing bracts, or as gypsum to the potting medium did not significantly reduce bract browning scores. These results and the development of bract browning in exposed, rather than enclosed tissue, suggest that factors other than calcium are involved in the development of bract browning. The light environment (full sun or 50% shade cloth) had a greater effect than irrigation frequency on bract browning of ‘Sunflare’ and ‘Olympic Flame’ waratahs in 2001. Waratahs grown under 50% shade cloth showed less bract browning at flower maturity than waratahs grown in full sun. This result was corroborated by subsequent experiments in 2002 and 2003. For example, in 2002, shade cloth reduced browning and bract loss by 30-60% at flower maturity, compared to waratahs grown in full sun. Shading waratahs from bud initiation in late summer (December-January) or bud opening in late winter (July-August) was equally effective in reducing browning. Shade cloth (50%) significantly reduced the light intensity experienced by waratah plants throughout the day, as well as reducing the daily maximum temperature and minimum relative humidity. Natural shade conditions at the Royal National Park effectively prevented browning of floral bracts, although the smaller basal bracts still turned brown and senesced. The development of bract browning as waratahs matured was linked to the development of chronic photoinhibition, measured as a decrease in predawn photosynthetic efficiency using chlorophyll fluorescence techniques. Waratah bracts were unable to maintain efficient photosynthesis in full sun conditions and reached saturation of non-photochemical quenching at lower light intensities than leaves. This suggests that bract tissue is adapted to a lower light environment than leaf tissue. Outer bracts had a significantly lower photosynthetic efficiency (Fv/Fm) than leaves early in flower development, as they were exposed to the environment for a prolonged period. Outer bracts also began to senesce towards flower maturity, particularly in full sun, increasing their susceptibility to damage. Inner waratah bracts were able to maintain a high photosynthetic efficiency prior to exposure, but photosynthetic efficiency decreased significantly at the intermediate stage of floral development, as inner bracts were no longer protected by outer bracts. Waratah leaves were more resilient than bracts, and did not suffer from chronic photoinhibition or browning during flower development. The increased susceptibility of bracts to photoinhibition and browning parallels results in other species, such as Dendrobium, where floral tissue experiences photoinhibition, bleaching and necrosis at lower light intensities than leaf tissue. Bracts on shaded waratahs maintained higher chlorophyll, carotenoid and anthocyanin concentrations than sun-exposed bracts, giving more intense flower colour and higher quality blooms. The significant decrease in bract pigmentation in the sun is likely to be a result of pigment destruction following photoinhibition, and has been noted in susceptible tissues of other species, such as Illicium (star anise) leaves. The presence of anthocyanins did not reduce bract browning in waratahs, with the concentration of UV-absorbing compounds showing a stronger positive correlation with protection from photoinhibition than the concentration of anthocyanins. However, anthocyanin concentrations were significantly lower in sun-exposed bracts, and brown compounds appeared to replace anthocyanins in the epidermal cells of brown bracts. Thus, it seems likely that browning in waratah bracts is the visible manifestation of oxidative damage to cell components, following chronic photoinhibition. Light-induced oxidative damage can lead to yellowing and pigment bleaching, lipid peroxidation, the development of necrotic lesions and senescence. However, lipid peroxidation as measured by the malionaldehyde assay gave no indication of oxidative damage to waratah bract tissue. This was probably due to the presence of anthocyanins and other flavonoids and sugars other than sucrose in bract tissue interfering with the colourimetric measurement of thiobarbituric acid reactive substances. The extensive planting of waratahs in NSW in the last five years suggests that the total value of lost production due to bract browning is likely to increase in the future. The browning disorder may also prevent the establishment of waratahs in other markets, as international cut-flower markets demand high quality blooms free from blemishes. The results of this study show that bract browning, photoinhibition and pigment loss are minimised by protecting waratahs from high light intensities from bud opening until harvest. However, the consequences of shading waratahs throughout the year require further investigation, as does the use of different percentages of shade cloth or other methods to reduce incident light.
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16

Montalbano, Giuseppina. "Evaluation of the antimicrobial, anti-inflammatory, regenerative and wound healing properties of the bracket fungus ganoderma lucidum." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/116592/2/Giuseppina_Montalbano_Thesis.pdf.

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Ganoderma lucidum, a saprophytic bracket fungus native to Queensland’s tropical rainforests, was traditionally used to heal wounds and ensure smooth tissue regeneration. Its pharmaceutical formulations such as teas, decoctions and capsules are claimed to cover a range of diseases, however, the alleged pharmacological properties of G. lucidum have not yet been fully scientifically validated. This study has demonstrated G. lucidum’s in vitro role as a wound healing agent as a result of its concomitant and/or predominant antibacterial, anti-inflammatory and regenerative properties. This research will contribute to a development of a novel therapeutic for the treatment of chronic non-healing wounds.
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17

Von, Richter Lotte Victoria. "Native plants of Eastern Australia as bedding plants." Thesis, The University of Sydney, 1996. https://hdl.handle.net/2123/27551.

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Bedding plants are used extensively in many landscaping situations. The majority of bedding plants marketed commercially are exotic species with only limited propagation material of Australian species available. The objectives of this work was to assess Australian short—lived perennial species as bedding plants with particular reference to their ease of propagation from seed. An extensive survey of Eastern states Australian native annual and short lived perennial species has identified the following species as showing potential as bedding plants.
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18

Lenz, Tanja. "The effect of resource dynamics on invasive annual and native perennial grasses in grasslands of the mid-north of South Australia /." Title page, table of contents and abstract only, 2004. http://web4.library.adelaide.edu.au/theses/09PH/09phl575.pdf.

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19

Buziak, Renata Monika. "Biochromes: Perceptions of Australian Medicinal Plants through Experimental Photography." Thesis, Griffith University, 2016. http://hdl.handle.net/10072/366679.

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This practice-led visual arts research project uses photography to represent medicinal plants of Minjerribah (North Stradbroke Island), and provides a visual articulation of the actions of decay and regeneration. It draws on natural science and extensive consultations and discussions with members of the Quandamooka community of Minjerribah. I have a particular interest in medicinal plants that stems from my childhood spent growing up in the small town of Janów Lubelski in Southeast Poland. My grandmother had a special knowledge of making infusions from local herbs, and remedies from twigs and berries. In an effort to find a sense of belonging in Australia, I brought this experience of Polish folk medicine into my new locale alongside my ecological concerns for maintaining biodiversity and preserving the natural environment. Focusing on medicinal plants from Minjerribah, this research project is grounded in field trips, and the long process of building precious relationships with the local Quandamooka Peoples. This research emphasises the importance of the protocols and processes involved in working with Aboriginal and Torres Strait Islander communities, the respectful treatment of cultural property, and the productive outcomes of sharing stories. I have learned much from my regular visits with Minjerribah residents and from literature about the Aboriginal and Torres Strait Islander peoples, their knowledge systems, traditions, and the significance of their connection to country, particularly in relation to plant culture.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Queensland Colledge of Art
Arts, Education and Law
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20

Wickens, Kristen M. "A search for biologically active compounds in Acacia (Mimosaceae) species." Thesis, Curtin University, 2003. http://hdl.handle.net/20.500.11937/1262.

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Indigenous Australians were also known to use plants for medicinal purposes. For thousands of years, Indigenous Australians have used native plants as a source of medicinal agents. Some tribes living in Central Australia still, to this day, prefer to use traditional medicines in favour of the more common and readily available western medicines. A number of plant species endemic to Australia are listed in various Aboriginal pharmacopoeias, with approximately one-third of those species belonging to two genera, Acacia and Eremophila. Of the 1100 recognised species of Acacia, approximately 900 occur in Australia. At least thirty of these species were utilised by the Indigenous Australians as a source of medicine. Extracts of 8 Acacia species were screened using four frontline bioassays. These were the brine shrimp lethality test, the crown gall tumour assays, the disc diffusion antibiotic assay and the seed germination test to determine if any of the species were biologically active. Of all the species screened, Acacia pruinocarpa showed the most promise. The species demonstrated significant activity at concentrations at low as 3.7ppm, which is well below the standard 400ppm exhibited by potassium dichromate (Sam, 1993). Acacia adsurgens and A. dictophleba were the next two promising species exhibiting activity at concentrations of 16.12ppm and 37ppm respectively. This was a trend that was also observed in the Lettuce seed germination test for allelopathy with these three species showing the most promise. Interestingly the potency of A. pruinocarpa extract decreased significantly when it was re- screened after being put through a polyamide column. It can therefore be suggested that as tannins are removed by the polyamide column, the biological activity exhibited by A. pruinocarpa is a result of the tannin content in the species (2%), although more testing is required.Both A. pruinocarpa and A. adsurgens showed promise as anti-tumour activity when used in the Crown Gall Tumour Assay (CGTA). Acacia pruinocarpa and A. adsurgens both exhibited significant activity when compared to the control producing inhibition percentages of 31% and 37% respectively. Surprisingly, only one of the Acacia species tested inhibited pathogenic growth when tested on the common pathogens Staphylococcus aureus, Streptococcus pyogens and Candida albicans. Acacia bivenosa was the only species to exhibit any activity when tested on the pathogens. This activity, however is not considered to be significant, as the species was only active against one of pathogens tested, Staphylococcus aureus. In order to be considered to be significant, a species must be active against two or more pathogens. It is however, worthy of further evaluation. Acacia species are among the large number of plants that have long been regarded sources of biological activity. This study was guided by the indigenous use of Acacia species as sources of medicine, which led to the use of front-line bioassays. All of the species tested exhibited some form of biological activity. Acacia pruinocarpa demonstrated the most promise as a source of novel biologically active compounds exhibiting activity at very low concentrations. Such compounds have not been determined as it was outside the scope of this study to identify the active constituents of this species. However, it has been suggested that tannins are responsible for eliciting some of the activity observed in A. pruinocarpa. All of the species screened in this study are worthy of further evaluation. The bioassays used in this study are good examples of front-line bioassays. All of the tests used in the study fulfil the criterion, which defines a good test.
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21

Reiter, Noushka Hedy, and noushka reiter@dse vic gov au. "Borya mirabilis steps in the recovery of a critically endangered Australian native plant." RMIT University. Applied Sciences, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20090227.160625.

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Borya mirabilis is one of the world's most critically endangered plants. The research in this thesis has illuminated key aspects of: its reproductive biology; interspecies and intraspecies molecular relationships, mycorrhizal status, tissue culture potential and disease threats. Each of these aspects has fundamental management implications for the active management of B. mirabilis. Floral observations of B. mirabilis and related species affirmed the uniqueness of the Boryaceae amongst the Asparagales. B. mirabilis had an unusually high number of floral abnormalities compared with other species of Borya observed. B. mirabilis is fly-pollinated. Pollen of Borya species showed little difference in the characteristics of mature pollen between species, with viable pollen being prolate and unicolpate with a single colpa-style aperture and a unique patterning of the pila. The structural immaturity of B. mirabilis pollen correlated with evidence from pollen growth experiments, where B. mirabilis pollen had extremely low germination rates, with those grains that did germinate being slow to do so and with slow-growing pollen tubes compared to those of fertile Borya species. Examination of the ovules of B. mirabilis showed that morphologically they were viable compared to viable Borya species. The field population of B. mirabilis was crossed, with one seed produced (the first recorded seed for th is species). Cross-pollination using the pollen of the closely related B. constricta and B. sphaerocephala with B. mirabilis ovules proved unsuccessful. Examination of the chromosome number of B. mirabilis showed that it had approximately 66 chromosomes and is probably hexaploid, relative to the diploid number of 26 in B. constricta. This may explain its low fertility. Interspecies and intraspecies relationships of the Boryaceae and Borya mirabilis were investigated using sequences of chloroplast and nuclear DNA. The closest similarities to B. mirabilis were B. constricta and B. sphaerocephala. B. mirabilis may have emerged from alloploidy of these species in the past. Because of the consistent similarities of B. mirabilis and B. constricta chloroplast sequences, it is proposed that both shared a common ancestor with a chromosome number of 2n=22. A malfunction n meiosis may have resulted in ovules with 2n=44. The high similarity of the nuclear ribosomal ITS region DNA suggests that the nuclear DNA was derived from B. sphaerocephela. B. mirabilis may be an allopolyploid, from fertilisation of a diploid ovule of B. constricta with haploid pollen of B. sphaerocephala, resulting in a reproductively isolated polyploidy of low fertility. The wild population of B. mirabilis was determined to have a small amount of genetic variation. The genetic variation in the field population w as not fully reflected in the ex-situ population. An effective means of micro-propagation of B. nitida for use in B. mirabilis has been established, providing an effective means of mass production of the species. The research has determined: a suitable explant (shoot tips) for regeneration; an effective means of reducing contamination in tissue culture (PPM); what medium is required to micro-propagate the species (LMHM); an appropriate gelling agent (Phytagel); and a practical method for inducing roots on the shoots grown in tissue culture. B. mirabilis has been established as mycorrhizal. The predominant mycorrhizal association is a nodular arbuscular mycorrhiza, present in the form of coils in root nodules over wetter months and as spores in these nodules over dryer months. A significant increase in the health of the ex-situ population of B. mirabilis was recorded after addition of soil containing fine roots of the wild population. Of the plants associated with the wild population, Callitris rhomboidea had the most morphologically similar vesicular arbuscular mycorrhizal relationship. But molecular identification was not achieved due to recalcitrance of DNA in PCR attempts. Potential translocation sites for some of the ex-situ population of B. mirabilis were examined for Phytophthora infestation. Reid's Lookout and Mackey's Peak were infected with P. cinnamomi. Vegetation at Mackey's Peak displayed characteristic infection symptoms, resulted in isolates of P. cinnamomi from baiting and would directly receive runoff from both the walking track and the existing infested B .mirabilis site. At the Reid's Lookout site, both walking track and proposed translocation site were infested with P. cinnamomi, yet did not display the associated symptoms in the vegetation. The Pine Plantation translocation site was uninfected at the level of sampling undertaken. Its vegetation did not display any characteristic infection symptoms and was not isolated when soil samples were baited. It was therefore chosen for translocation and so far the plants are healthy and actively growing. This research has provided critical knowledge to aid the recovery team in its current and future endeavours to manage this species and bring it back from the brink of extinction.
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22

Chowdhury, Shukti Rani. "Establishment of regeneration and transient transformation systems for Australian native resurrection plant Tripogon loliiformis." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/132682/1/Shukti%20Rani_Chowdhury_Thesis.pdf.

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This thesis contributed to unlock the regeneration and transient transformation systems for Tripogon loliiformis, an Australian native extremophile. This resurrection grass has suitable structural, physiological and molecular mechanisms to survive in extreme desiccation. The regeneration and transient transformation systems will assist in establishing a stable transformation system for Tripogon which will enable more understanding of its unique genes for coping abiotic stresses. This may contribute to the bioengineering of these genes to important cereal crops like rice, wheat, maize and sorghum for the improvement of abiotic stress tolerance.
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23

Parisi, Ann Margaret. "Investigation of Secondary Metabolite Production in Selected Australian Native Species via Plant Cell Suspension Culture." Thesis, Griffith University, 2006. http://hdl.handle.net/10072/366129.

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Natural products and natural-product-derived substances comprised about 35% of the total pharmaceuticals market volume of US$230 billion in 1996 (Wessjohann, 2000). The success of natural-based drugs can be attributed to nature’s ability to induce effects by chemical means and many of these chemicals are able to pass species boundaries to cause an effect. Since plant secondary metabolites have evolved in the interaction with other organisms, many of them have interesting biological or therapeutical activities that are useful to man. In addition to their intriguing chemistry a number of these compounds are economically important, serving as pharmaceuticals, aromatics, fragrances, stimulants, colours and pesticides. Plant cell culture is viewed as a potential means of producing useful plant products without the inherent problems associated with conventional agriculture. Undifferentiated cell suspension cultures have the potential to produce varied secondary metabolites by the alteration of culture conditions or addition of chemicals to elicit expression of different metabolic pathways. Suitable substrate compounds may be biotransformed to a desired product using plant cell cultures. Biotransformation can produce compounds that can then be replicated by synthetic means or produce novel compounds that have previously not been identified or recognised as important. This thesis describes the initiation of plant suspension cultures for the purposes of examining the production of secondary metabolites of selected Australian native rainforest species.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Biomedical Science
Science, Environment, Engineering and Technology
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24

Bunny, F. "The biology, ecology and taxonomy of Phytophthora citricola in native plant communities in Western Australia /." Access via Murdoch University Digital Theses Project, 1996. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20061122.122739.

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25

Bunny, Felicity J. "The biology, ecology and taxonomy of Phytophthora citricola in native plant communities in Western Australia." Thesis, Bunny, Felicity J. (1996) The biology, ecology and taxonomy of Phytophthora citricola in native plant communities in Western Australia. PhD thesis, Murdoch University, 1996. https://researchrepository.murdoch.edu.au/id/eprint/492/.

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The objectives of the project were to develop an understanding of the disease dynamics caused by Phytophthora citricola in native plant communities in the south of Western Australia. Prior to 1983, the pathogen had only been reported twice from Australian forests. Since then, P. citricola has been extensively recorded from plant communities north and south of Perth, and is currently the second most frequently recovered Phytophthora species from the northern jarrah forest and the northern sandplains. The objectives were addressed by examining the biology, ecology and taxonomy of isolates of P. citricola local to the southwest. Examination of the intraspecific variation of P. citricola by isozyme analysis resolved three major electrophoretic subgroups (SG), and these were aligned with morphological and cultural variation within the species. One electrophoretic SG was confined to forested areas. This SG differed from other SGs in sporangial dimensions, growth rate on two media and in vitro sensitivity to phosphonate. A redescription of the species may be warranted. P. citricola was positively associated with two roads in the northern jarrah forest. Road surfaces were sampled, then soil overburden was removed and the surface of the concreted lateritic layer beneath was sampled. Isolation of P. citricola declined away from the road into the adjacent forest and was more frequently recovered from the caprock (up to 1 metre below soil surface) than from the soil surface. The most probable source of introduction was from infested soil on vehicles using the roads. Oospores were shown to be produced in two soils, a lateritic gravelly loam and sand, and in plants. In soil, the electrophoretic SG confined to the forest (loamy soil) produced only limited numbers of oospores in the sandy soil of the northern sandplain. The restriction of this SG to the forested areas is probably physiological, rather than limited dispersal, with the SG currently occupying the full extent of its range. Estimation of the relative persistence of oospores, zoospores and plant material colonised by P. citricola established that only oospores (either free in soil or in colonised plant material) were important in long tern survival in soil. Oospores were still viable after six months at two field sites, and after 18 months in soil in the laboratory. Phosphonate is currently the most promising method of control of Phytophthora induced disease in native plant cornmunites of the southwest. The efficacy of phosphonate against P. citricola was examined in vivo and in vitro against two SGs. Phosphonate successfully inhibited lesion growth of both SGs in vivo, but of only one electrophoretic subgroup in vitro. The ecological implications of infestation of native plant communities in the southwest of Australia are discussed.
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26

Bunny, Felicity J. "The biology, ecology and taxonomy of Phytophthora citricola in native plant communities in Western Australia." Murdoch University, 1996. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20061122.122739.

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The objectives of the project were to develop an understanding of the disease dynamics caused by Phytophthora citricola in native plant communities in the south of Western Australia. Prior to 1983, the pathogen had only been reported twice from Australian forests. Since then, P. citricola has been extensively recorded from plant communities north and south of Perth, and is currently the second most frequently recovered Phytophthora species from the northern jarrah forest and the northern sandplains. The objectives were addressed by examining the biology, ecology and taxonomy of isolates of P. citricola local to the southwest. Examination of the intraspecific variation of P. citricola by isozyme analysis resolved three major electrophoretic subgroups (SG), and these were aligned with morphological and cultural variation within the species. One electrophoretic SG was confined to forested areas. This SG differed from other SGs in sporangial dimensions, growth rate on two media and in vitro sensitivity to phosphonate. A redescription of the species may be warranted. P. citricola was positively associated with two roads in the northern jarrah forest. Road surfaces were sampled, then soil overburden was removed and the surface of the concreted lateritic layer beneath was sampled. Isolation of P. citricola declined away from the road into the adjacent forest and was more frequently recovered from the caprock (up to 1 metre below soil surface) than from the soil surface. The most probable source of introduction was from infested soil on vehicles using the roads. Oospores were shown to be produced in two soils, a lateritic gravelly loam and sand, and in plants. In soil, the electrophoretic SG confined to the forest (loamy soil) produced only limited numbers of oospores in the sandy soil of the northern sandplain. The restriction of this SG to the forested areas is probably physiological, rather than limited dispersal, with the SG currently occupying the full extent of its range. Estimation of the relative persistence of oospores, zoospores and plant material colonised by P. citricola established that only oospores (either free in soil or in colonised plant material) were important in long tern survival in soil. Oospores were still viable after six months at two field sites, and after 18 months in soil in the laboratory. Phosphonate is currently the most promising method of control of Phytophthora induced disease in native plant cornmunites of the southwest. The efficacy of phosphonate against P. citricola was examined in vivo and in vitro against two SGs. Phosphonate successfully inhibited lesion growth of both SGs in vivo, but of only one electrophoretic subgroup in vitro. The ecological implications of infestation of native plant communities in the southwest of Australia are discussed.
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27

Barrett, Sarah. "Phytotoxic effects of phosphite in native plant communities on the south coast of Western Australia." Thesis, Barrett, Sarah (2001) Phytotoxic effects of phosphite in native plant communities on the south coast of Western Australia. PhD thesis, Murdoch University, 2001. https://researchrepository.murdoch.edu.au/id/eprint/32427/.

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28

Wickens, Kristen M. "A search for biologically active compounds in Acacia (Mimosaceae) species." Curtin University of Technology, Department of Environmental Biology, 2003. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=15212.

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Indigenous Australians were also known to use plants for medicinal purposes. For thousands of years, Indigenous Australians have used native plants as a source of medicinal agents. Some tribes living in Central Australia still, to this day, prefer to use traditional medicines in favour of the more common and readily available western medicines. A number of plant species endemic to Australia are listed in various Aboriginal pharmacopoeias, with approximately one-third of those species belonging to two genera, Acacia and Eremophila. Of the 1100 recognised species of Acacia, approximately 900 occur in Australia. At least thirty of these species were utilised by the Indigenous Australians as a source of medicine. Extracts of 8 Acacia species were screened using four frontline bioassays. These were the brine shrimp lethality test, the crown gall tumour assays, the disc diffusion antibiotic assay and the seed germination test to determine if any of the species were biologically active. Of all the species screened, Acacia pruinocarpa showed the most promise. The species demonstrated significant activity at concentrations at low as 3.7ppm, which is well below the standard 400ppm exhibited by potassium dichromate (Sam, 1993). Acacia adsurgens and A. dictophleba were the next two promising species exhibiting activity at concentrations of 16.12ppm and 37ppm respectively. This was a trend that was also observed in the Lettuce seed germination test for allelopathy with these three species showing the most promise. Interestingly the potency of A. pruinocarpa extract decreased significantly when it was re- screened after being put through a polyamide column. It can therefore be suggested that as tannins are removed by the polyamide column, the biological activity exhibited by A. pruinocarpa is a result of the tannin content in the species (2%), although more testing is required.
Both A. pruinocarpa and A. adsurgens showed promise as anti-tumour activity when used in the Crown Gall Tumour Assay (CGTA). Acacia pruinocarpa and A. adsurgens both exhibited significant activity when compared to the control producing inhibition percentages of 31% and 37% respectively. Surprisingly, only one of the Acacia species tested inhibited pathogenic growth when tested on the common pathogens Staphylococcus aureus, Streptococcus pyogens and Candida albicans. Acacia bivenosa was the only species to exhibit any activity when tested on the pathogens. This activity, however is not considered to be significant, as the species was only active against one of pathogens tested, Staphylococcus aureus. In order to be considered to be significant, a species must be active against two or more pathogens. It is however, worthy of further evaluation. Acacia species are among the large number of plants that have long been regarded sources of biological activity. This study was guided by the indigenous use of Acacia species as sources of medicine, which led to the use of front-line bioassays. All of the species tested exhibited some form of biological activity. Acacia pruinocarpa demonstrated the most promise as a source of novel biologically active compounds exhibiting activity at very low concentrations. Such compounds have not been determined as it was outside the scope of this study to identify the active constituents of this species. However, it has been suggested that tannins are responsible for eliciting some of the activity observed in A. pruinocarpa. All of the species screened in this study are worthy of further evaluation. The bioassays used in this study are good examples of front-line bioassays. All of the tests used in the study fulfil the criterion, which defines a good test.
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29

D'Souza, Nola Kim. "Biological control of Phytophthora cinnamomi: The potential of Western Australian native legumes to protect susceptible plant species." Thesis, D'Souza, Nola Kim (2001) Biological control of Phytophthora cinnamomi: The potential of Western Australian native legumes to protect susceptible plant species. Honours thesis, Murdoch University, 2001. https://researchrepository.murdoch.edu.au/id/eprint/32764/.

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ABSTRACT The plant pathogen Phytophthora cinnamomi is having a major negative impact on the biodiversity of native ecosystems in the south west of Western Australia. Acacia pu/chella has previously been shown to suppress P. cinnamomi in the jarrah forest of Western Australia and protect susceptible species from infection. This has management implications for the control of P. cinnamomi in rehabilitated bauxite pits infested with the pathogen and severely diseased forest areas. The objective of this thesis was to determine if other Western Australian native legume species have the potential to biologically control P. cinnamomi. In a rehabilitated bauxite pit trial, five Acacia species were planted with Banksia grandis, to determine their ability to protect this highly susceptible species against P. cinnamomi infection. A. pulchella protected B. grandis from infection for over a year. This protection was not the result of a decrease in soil moisture or soil temperature, as was previously suggested. A. urophylla, A. extensa, A. latericola and A. drummondii did not protect B. grandis in this trial. The trial was replicated in the glasshouse under conditions conducive to the pathogen. The infection of B. grandis by P. cinnamomi was delayed for up to 7 weeks by all of these Acacia species; however, none of them protected B. grandis from eventual mortality. In a glasshouse soil inoculation trial, native legumes other than A. pulchella were able to reduce the soil inoculum potential of P. cinnamomi. Based on these findings, the species with the greatest potential for biological control of P. cinnamomi along with A. pulchella were A. extensa, A. stenoptera and A. a/ata. 11 By assessing the roots of soil inoculated native legumes from the glasshouse trial, P. cinnamomi was found to asymptomatically infect fine lateral roots of some species and sporulate from them. These species can potentially harbour the pathogen and allow for an inoculum increase when environmental conditions are favourable. A. urophylla and Viminaria juncea were the species with the least potential for biological control of P. cinnamomi due to this finding. A possible management tool for bauxite pits in infested areas and in severely diseased forest areas is the ability to influence the density and composition of species used for rehabilitation, by manipulating the seed mix ratio. The implications of this study would be to increase seed in a seed mix of those legume species with the potential for biological control and decrease seed of those species that can harbour the pathogen. However, before rehabilitation management practices are adjusted, further investigation is required to understand how P. cinnamomi suppression occurs and whether it is transferable to a natural environment. The actions of P. cinnamomi suppression by legume species and future research directions are discussed.
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Docker, Benjamin Brougham. "Biotechnical engineering on alluvial riverbanks of southeastern Australia a quantified model of the earth-reinforcing properties of some native riparian trees /." Connect to full text, 2003. http://hdl.handle.net/2123/1688.

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Thesis (Ph. D.)--School of Geosciences, Faculty of Science, University of Sydney, 2004.
Degree awarded 2004; thesis submitted 2003. Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Geosciences, Faculty of Science. Title from title screen (viewed 13 January 2009). Includes bibliographical references. Also available in print form.
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31

Patel, Minaxi. "The potential for a novel alcoholic drink prepared from the New Zealand native plant Cordyline australis (ti kōuka)." AUT University, 2009. http://hdl.handle.net/10292/894.

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Some New Zealand indigenous plants may offer unique qualities that can be used to secure an exclusive niche in the alcoholic drinks market in the same way that Scotch whisky and tequila are strongly identified with the country of origin, Scotland and Mexico. Tequila is a spirit distilled from a fermented agave, dry adapted lily. Agave is in the family Agavaceae, a notable New Zealand member of which is the common cabbage tree or ti kōuka (Cordyline australis). Similarly, to the agave having a fermentable core, ti kōuka has carbohydrate (inulin) content in its young stems and roots that can be hydrolysed in acidic suspensions or by enzyme hydrolysis to yield fructose. The main objective of this thesis was to systematically research the feasibility of the production of a tequila-like spirit from ti kōuka stem, profiling the chemical properties of the spirit with a view of future commercial production of an iconic New Zealand spirit. The initial stage of the thesis focused on extracting inulin from the ti kōuka stem and hydrolysing (by both acid and enzyme) it to yield reducing sugar. The sugar concentration yielded was too low (~ 10 to 15%) to be fermented and distilled economically. Rather, the ti kōuka extract was evaporated to produce flavoured products by the Maillard reaction, a reaction between amino acids and sugars. The flavoured compounds were then infused with potable ethanol. In outline, the dried stem was hydrolysed with an inulinase at 60°C for 1 hour. The pH was adjusted to 10 with sodium hydroxide and evaporated at 60°C for 65 hours. The dried extract was reconstituted with water, centrifuged and the supernatant infused with portable ethanol to yield final different concentrations of 80, 67, 57 and 50%. The ethanol treatments simultaneously extracted flavour and colour to varying degrees. Next, sugars and amino acids were analysed in the ti kōuka stems by liquid chromatography. The most abundant sugar present in the ti kōuka after inulinase hydrolysis was fructose and the dominant amino acids were arginine, leucine, lysine, and aspartic acid/aspargine and glutamic acid/glutamine. Amino acids and reducing sugar were also analysed at different stages of the spirit production. The reducing sugar content decreased during each step of the process. The relative concentrations of arginine, leucine and lysine decreased while that of aspartic and glutamic acids increased during the whole process of making the spirit. Model systems were then used to simulate the reactions taking place between the amino acids and reducing sugar present in the ti kōuka extract. The colour of the models became darker as a function of time, accumulating more brown pigment containing the flavoured compounds. Increasing the pH and concentration of the amino acids in the reaction mixture also increased the browning pigment formation. Dichloromethane and n-pentane and diethyl ether solvent extraction of the spirits and analysis of volatiles by gas chromatography- mass spectrometry revealed that the chemical profiles of the spirits were different from those of the commercial spirits, gin, tequila and whisky. Sensory evaluation was performed on four variations of the spirit, and demonstrated that the creations were consumer-acceptable. The costs and other issues involved in producing and marketing such a spirit were identified, the major selling point being geographical exclusivity.
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Mahmood, Ako. "Investigations into the ecology and management of the invasive plant Galenia pubescens within the native temperate grasslands of Victoria, Australia." Thesis, Federation University Australia, 2016. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/154244.

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Plant invasions of natural ecosystems are one of the major threats to the conservation of biological diversity across nearly all biogeographical regions in the world. This thesis focuses on Galenia pubescens (Carpet weed) as a case study of possible approaches to the potential management of environmental weed species. G. pubescens is a woody prostrate perennial plant that is becoming a serious threat to Australian temperate grasslands, surrounding agricultural areas and conservation reserves. It is indigenous to South Africa and was first recorded in Australia in the early 1900s, and it is an aggressive competitor against native species. It is difficult to control, and little information exists about its effects on natural ecosystems, and aspects of its biology and ecology. This study has investigated some important ecological characteristics of G. pubescens’ seeds and has experimented with different management strategies in combination with chemical control. It has also considered the potential for the expansion of the distribution of this species across suitable habitat in Australia under predicted elevated CO2 and drought conditions. Seeds of G. pubescens are shown to be able to germinate over a broad range of temperatures, but short bursts (5 minutes) of high temperatures (80oC to 120oC replicating possible exposures to a fire) reduced seed germination. Seed germination was positively favored by light and declined rapidly in darkness, decreasing by > 80% at a depth of only 0.5 cm in soil. This suggests that fire regimes might be useful in removing mature plants and controlling seed numbers on the surface, and that subsequent native seeding of undisturbed areas may assist in the long-term management of this noxious weed. A trial was conducted to determine the effect of treatment with a plant essential oil (pine oil) to limit the seed germination and seedling emergence of G. pubescens. This trial showed that the effects of pine oil application were significant (P<0.05). Germination was completely inhibited by application of pine oil at 5% or higher concentrations directly to seeds, and seedling emergence was reduced by between 90 and 100% in pot trials. These outcomes demonstrate the potential viability of pine oil as a long-term control option for this species. In field-based experiments, control strategies including herbicide control with glyphosate, organic herbicide control with pine oil, the application of mulch, and the addition of native seeds to the available seedbank (and all possible combinations of these techniques), were tested. The study showed that one single treatment of a G. pubescens infestation without undertaking a secondary treatment is insufficient to control the G. pubescens infestation or to encourage native regeneration, but that a combined strategy, employing all the aforementioned techniques, is more effective. It is however suggested that full regeneration of the area may not be possible unless further restoration programs are instituted after the cycle of G. pubescens’ treatment has been completed. The thesis also assessed the control effects of chemical control combined with a prescribed spring burning. Assessment of the resulting aboveground vegetation of G. pubescens has shown that a combination of chemical control and late-spring burning can reduce the cover of non-native species such as G. pubescens, suggesting that this could be a useful tool in their management. Finally, this study has supported the view that the growth of G. pubescens will be significantly enhanced in a future climate with an enriched atmospheric CO2 concentration. These climatic changes will have important implications for management of this noxious weed in the future.
Doctor of Philosophy
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33

Horsnell, Tara Kathleen. "Quantifying thresholds for native vegetation to salinity and waterlogging for the design of direct conservation approaches." University of Western Australia. School of Environmental Systems Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0082.

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A field-based project was undertaken to develop and test a mechanism which would allow for the correlation of the health of vegetation surrounding playa lakes in south-west Australia with the natural variation in salinity and waterlogging that occurs spatially and temporally in natural systems. The study was designed to determine threshold ranges of vegetation communities using moderately extensive data over short temporal periods which will guide the design of potential engineering solutions that manipulate hydrological regimes to ultimately conserve and protect native vegetation. A pair of playa lake ecosystems, surrounded by primary production land, was modelled with hydro-geological data collected from March 2006 to March 2007. The data was used to determine the hydroperiods of vegetation communities fringing playa lakes and provide insight into the areas and species that are most affected by extreme rainfall events which are hypothesised to have a significant, rapid deleterious effect on the ecosystems. The methodology was multi-faceted and included; a detailed topographical survey; vegetation surveys; hydrological and hydro-geological monitoring over a 12 month period. 4 The hydro-geological data and vegetation data was linked with the topographical survey at a high resolution for spatial analysis in a Geographic Information System (GIS) to determine the degree of waterlogging experienced by vegetation communities over the monitoring period. The study has found that the spatial and temporal variability of hydroperiods has been reduced by rising groundwater levels, a result of extensive clearing of native vegetation. Consequently populations are becoming extinct locally resulting in a shift in community composition. Extreme summer rainfall events also have a significant impact on the health of vegetation communities by increasing the duration of waterlogging over an annual cycle and in some areas expanding the littoral zone. Vegetation is most degraded at lower positions in the landscape where communities are becoming less diverse and dominated by salt tolerant halophytic species as a result of altered hydrological regimes. Some species appear to be able to tolerate groundwater depths of less than 2.0 m from the surface, however there are thresholds related to the duration at which groundwater is maintained at this depth. Potential engineering solutions include groundwater pumping and diverting water through drains to maintain sustainable hydroperiods for vegetation in areas with conservation value. The effectiveness and efficiency of the engineering solutions can be maximised by quantifying thresholds for vegetation that include sustainable durations of waterlogging. The study has quantified tolerance ranges to salinity and waterlogging with data collected over 12 months but species may be experiencing a transition period where they have 5 sustained irreversible damage that will result in their eventual mortality. With long-term monitoring, the methodology developed and tested in the study can be used to quantify the long-term tolerance ranges that are important for the application of conservation approaches that include engineering solutions.
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Prendergast, Kit Stasia. "Urban native bee assemblages and the impact of the introduced European honeybee on plant-pollinator networks in the southwest Australian biodiversity hotspot." Thesis, Curtin University, 2020. http://hdl.handle.net/20.500.11937/84947.

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The thesis of Kit Prendergast addressed impacts of urbanisation and introduced honeybees on native bees in southwest Australia. Additionally, efficacy of bee survey methods were evaluated. The study found remnant bushland, with high proportions of native flora, was of greater importance for supporting native bee populations, species, and pollinator networks, compared with residential gardens. Honeybees occupied distinct positions in pollinator networks, and altered network properties, with context-dependent impacts on native bees.
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Stenhouse, Renae N. "Ecology and management of bushland in Australian cities." University of Western Australia. School of Earth and Geographical Sciences, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0027.

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[Truncated abstract] Native vegetation (bushland) in urban areas remains in small, isolated patches embedded within a matrix of human-dominated land uses. Bushlands in urban areas have high biodiversity conservation and social values, and there has been a local-level movement towards protecting and managing urban bushlands in Australia. This thesis aims to test principles, theories and concepts relating to the ecology and management of bushland fragments in Australian cities ... A commonly used qualitative scale was compared with an ecologically based, quantitative technique developed in the research. The qualitative scale was found to be a reliable proxy for assessing vegetation condition, while also being more user-friendly for community groups and other bushland managers. The human-caused disturbances and weed cover in urban bushlands indicate a need for management intervention. Local government has an important role in local biodiversity management, yet there has been little research on this topic ... Positive partnerships developed where local governments have taken a ‘contract model’ approach to volunteer coordination, have a number of expectations of volunteer groups, and provide the groups with relatively high level of assistance. Also important is a local government that supports, respects, trusts and communicates with the community group, and recognises volunteers’ skills, knowledge and contributions. With increased resources allocated to local government bushland management and conservation, and coordination with community groups, the full potential of local bushland management would be realised.
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Karbaschi, Mohammad Reza. "Structural, physiological and molecular characterisation of the Australian native resurrection grass Tripogon loliiformis (F.Meull) C.E.Hubb during dehydration and rehydration." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/90050/1/Mohammad%20Reza_Karbaschi_Thesis.pdf.

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There is an urgent need to develop crops that can withstand future climates. Results from this thesis demonstrated that a native Australian resurrection grass exhibits structural, physiological and metabolic strategies to tolerate drying. These strategies may be utilized for the generation of stress tolerant crops.
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Docker, Benjamin Brougham. "Biotechnical engineering on alluvial riverbanks of southeastern Australia: A quantified model of the earth-reinforcing properties of some native riparian trees." Thesis, The University of Sydney, 2003. http://hdl.handle.net/2123/1688.

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It is generally accepted that tree roots can reinforce soil and improve the stability of vegetated slopes. Tree root reinforcement is also recognised in riverbanks although the contribution that the roots make to bank stability has rarely been assessed due to the reluctance of geomorphologists to examine riverbank stability by geomechanical methods that allow for the inclusion of quantified biotechnical parameters. This study investigates the interaction between alluvial soil and the roots of four southeastern Australian riparian trees. It quantifies the amount and distribution of root reinforcement present beneath typically vegetated riverbanks of the upper Nepean River, New South Wales, and examines the effect of the reinforcement on the stability of these banks. The ability of a tree to reinforce the soil is limited by the spatial distribution of its root system and the strength that the roots impart to the soil during shear. These two parameters were determined for the following four species of native riparian tree: Casuarina glauca, Eucalyptus amplifolia, Eucalyptus elata, and Acacia floribunda. The four species all exhibit a progressive reduction in the quantity of root material both with increasing depth and with increasing lateral distance from the tree stem. In the vertical direction there are two distinct zones that can be described. The first occurs from between 0 and approximately 15 % of the maximum vertical depth and consists of approximately 80 % of the total root material quantity. In this zone the root system consists of both vertical and lateral roots, the size and density of which varies between species. The second zone occurs below approximately 15 % of the maximum vertical depth and consists primarily of vertical roots. The quantity of root material in this zone decreases exponentially with depth due to the taper of individual roots. The earth reinforcement potential in terms of both geometric extent and the quantity of root material expressed as the Root Area Ratio (RAR) varies significantly from species to species. E. elata exhibited the highest values of RAR in soil zones beneath it while E. amplifolia reinforced a greater volume of soil than any of the other species examined. The increased shear resistance (Sr) of alluvial soil containing roots was measured by direct in-situ shear tests on soil blocks beneath a plantation. For three of the species (C. glauca, E. amplifolia, E. elata) Sr increased with increasing RAR measured at the shear plane, in a similar linear relationship. The shear resistance provided by A. floribunda roots also increased with increasing RAR at the shear plane but at a much greater rate than for the other three species. This is attributable to A. floribunda’s greater root tensile strength and therefore pull-out resistance, as well as its smaller root diameters at comparative RARs which resulted in a greater proportion of roots reaching full tensile strength within the confines of the test. Tree roots fail progressively in this system. Therefore determining the increased shear strength from the sum of the pull-out or tensile strengths of all individual roots and Waldron’s (1977) and Wu et al’s (1979) simple root model, would result in substantial over estimates of the overall strength of the soil-root system. The average difference between Sr calculated in this manner and that measured from direct in-situ shear tests is 10.9 kPa for C. glauca, 19.0 kPa for E. amplifolia, 19.3 kPa for E. elata, and 8.8 kPa for A. floribunda. A riverbank stability analysis incorporating the root reinforcement effect was conducted using a predictive model of the spatial distribution of root reinforcement beneath riparian trees within the study area. The model is based on measurements of juveniles and observations of the rooting habits of mature trees. It indicates that while the presence of vegetation on riverbank profiles has the potential to increase stability by up to 105 %, the relative increase depends heavily on the actual vegetation type, density, and location on the bank profile. Of the species examined in this study the greatest potential for improved riverbank stability is provided by E. amplifolia, followed by E. elata, A. floribunda, and C. glauca. The presence of trees on banks of the Nepean River has the potential to raise the critical factor of safety (FoS) from a value that is very unstable (0.85) to significantly above 1.00 even when the banks are completely saturated and subject to rapid draw-down. It is likely then that the period of intense bank instability observed within this environment between 1947 and 1992 would not have taken place had the riparian vegetation not been cleared prior to the onset of wetter climatic conditions. Typical ‘present-day’ profiles are critically to marginally stable. The introduction of vegetation could improve stability by raising the FoS up to 1.68 however the selection of revegetation species is crucial. With the placement of a large growing Eucalypt at a suitable spacing (around 3-5 m) the choice of smaller understorey trees and shrubs is less important. The effect of riparian vegetation on bank stability has important implications for channel morphological change. This study quantifies the mechanical earth reinforcing effect of some native riparian trees, thus allowing for improved deterministic assessment of historical channel change and an improved basis for future riverine management.
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Gibbs, Jane. "Asthma and Plants: Chemotaxonomic Relationships and Patterns of Asthma Incidence and Respiratory Symptoms, in Urban Coastal Versus Rural Highland Areas in South-East Queensland, Australia, with Special Reference to the Family Myrtaceae." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/366726.

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This thesis represents an exploratory and iterative study into the relationships of Australian native plants from the family Myrtaceae, with respiratory symptoms, specifically asthma. This relationship is explored from a chemo-taxonomic stance and the connections with other plants with related chemotaxonomy are underlined. The research was performed against a background of geographical comparison between an urban coastal area and a rural mountainous area 90 kilometres just north of Brisbane, Queensland, Australia. The focus was the possible contribution of Melaleuca quinquenervia to the occurrence of autumn respiratory symptoms, especially asthma. The research challenges current beliefs that wind-pollinated plants are the only sources of allergens and the major botanical health threat for those who suffer with asthma. There is some critical analysis of the current understanding of world patterns of asthma, with particular reference to the Global Initiative for Asthma (GINA) geographic compilations. In this study 380 children were skin-tested with a battery of commercial allergens including Eucalyptus. Comparisons among children from three coastal schools and students from one mountain school were made with a view to testing the hypothesis that proximate vegetation would affect responses to allergens. As hypothesised, significant differences were detected between the coastal and range students in responses to Eucalyptus, which flowers prolifically on the coast. Coastal children, compared to the rural children from the mountain area exhibited a significantly greater percentage of skin-test responses (p≤.05) to Eucalyptus, when all responses greater than zero were measured. In the next phase more comparisons were undertaken with a smaller group of adults and adolescents in the coast and range communities. A range of terpenes and oxidized terpenes was applied during skin tests along with commercial allergens. Coastal and range reaction profiles revealed that coastal participants exhibit greater skin reactivity. When a 3mm wheal cut-off is employed alpha-pinene response in the range group is notable. During this second phase ambient air sampling was carried out at the same time as participants measured peak expiratory flow (PEF) and recorded respiratory symptoms. Chemicals trapped on Tenax over spring and autumn were analysed via GCMS and the results combined with symptom variables to ascertain significant predictors of symptom change. Using stepwise and general linear regression significant relationships were demonstrated between PEF and beta pinene and limonene in ambient air. In both types of modelling several terpenes were shown to be significant predictors of respiratory symptoms. In the coastal group the addition of alpha or beta pinene to a General Linear Regression model predicting standardized peak flow, accounted to an additional 20% of the variance in autumn. The model consisted of ozone, nitrogen dioxide and particulates less than 10 micron, all lagged three days. For spring, the additional variance explained was only 6 % and for spring an autumn combined it was 5%. Significant relationships were also demonstrated between linalool levels and preventer and reliever usage. The results support the hypotheses regarding the role of terpenes as having a possible role in the acquisition and exacerbation of asthma. Additionally a number of floral studies resulted in chemical profiles being elucidated for flowers from popular plants in Australia. Tenax collections of vapours from some household and lifestyle products resulted in chemical profiles for popular items. In conclusion, some observations about vegetation and patterns of asthma have been made and a new model of asthma acquisition proposed.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Public Health
Griffith Health
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39

Frevola, Danielle Marie Frevola. "Can Surrounding Land Use Promote Phenotypic Plasticity and Invasion Success in Wetland Plants Through Variable Nutrient Regimes?" The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531230832080876.

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40

Mikli, Markus H. "Revegetation of coal mine dumps to ameliorate effects of acidic seepage." Thesis, Curtin University, 2001. http://hdl.handle.net/20.500.11937/213.

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Species prescriptions are developed for revegetating abandoned acidic coal overburden seepage sites in the Collie region of Western Australia. The research involved selecting appropriate plant species and determining successful methods of enhancing revegetation. Candidate species were screened for tolerance to acidic overburden materials, local climate conditions and metal toxicity. Methods tested included improving spoil conditions and trialing an alternative method for seeding.Twelve species of native plants were tested for tolerance in two acid overburden materials in pot and field trials. Eucalyptus robusta is the most tolerant, Eucalyptus camaldulensis and Eucalyptus cladocalyx are highly tolerant, Eucalyptus rudis and Melaleuca hamulosa demonstrate potential, provided adequate soil moisture is available.An important growth restriction factor in acid soils is the presence of free aluminium ions. A glasshouse trial performed on seven species for tolerance to aluminium toxicity revealed E. robusta as most tolerant and E. camaldulensis and Kunzea ericifolia a highly tolerant. E. rudis and M. hamulosa are moderately tolerant, but E. cladocalyx and Eucalyptus diversicolor are very sensitive to aluminium.Various methods were trialed to increase growth of seedlings transplanted on to acidic overburden sites. Both commercial cow manure and slow-release fertiliser tablets increase growth, whereas commercial potting mix and lime do not. Inoculation of plants with the ectomycorrhiza fungus Pisolithus tinctorius increases the amount of infection in roots but does not enhance plant growth.Supplementary fertilisation is necessary to maintain growth (nitrogen) and restore chlorophyll production (phosphorus) in fast growing eucalypt seedlings planted into typical acidic spoils. Poor levels of nutrient availability in such acidic sites appear to be the primary factor in retarding growth. In the absence of supplementation, foliage reddening is observed in several species.An alternative method of seeding dumps is fascining. Prepared dump surfaces may be covered with capsule-laden branchwood of myrtaceous species. Material of the locally available Kunzea ericifolia is effective in producing many seedlings. Subsequent seedling growth is enhanced with fertiliser and lime addition.
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Mikli, Markus H. "Revegetation of coal mine dumps to ameliorate effects of acidic seepage." Curtin University of Technology, Department of Environmental Biology, 2001. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=12531.

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Species prescriptions are developed for revegetating abandoned acidic coal overburden seepage sites in the Collie region of Western Australia. The research involved selecting appropriate plant species and determining successful methods of enhancing revegetation. Candidate species were screened for tolerance to acidic overburden materials, local climate conditions and metal toxicity. Methods tested included improving spoil conditions and trialing an alternative method for seeding.Twelve species of native plants were tested for tolerance in two acid overburden materials in pot and field trials. Eucalyptus robusta is the most tolerant, Eucalyptus camaldulensis and Eucalyptus cladocalyx are highly tolerant, Eucalyptus rudis and Melaleuca hamulosa demonstrate potential, provided adequate soil moisture is available.An important growth restriction factor in acid soils is the presence of free aluminium ions. A glasshouse trial performed on seven species for tolerance to aluminium toxicity revealed E. robusta as most tolerant and E. camaldulensis and Kunzea ericifolia a highly tolerant. E. rudis and M. hamulosa are moderately tolerant, but E. cladocalyx and Eucalyptus diversicolor are very sensitive to aluminium.Various methods were trialed to increase growth of seedlings transplanted on to acidic overburden sites. Both commercial cow manure and slow-release fertiliser tablets increase growth, whereas commercial potting mix and lime do not. Inoculation of plants with the ectomycorrhiza fungus Pisolithus tinctorius increases the amount of infection in roots but does not enhance plant growth.Supplementary fertilisation is necessary to maintain growth (nitrogen) and restore chlorophyll production (phosphorus) in fast growing eucalypt seedlings planted into typical acidic spoils. Poor levels of nutrient availability in such acidic sites appear to be the primary factor in ++
retarding growth. In the absence of supplementation, foliage reddening is observed in several species.An alternative method of seeding dumps is fascining. Prepared dump surfaces may be covered with capsule-laden branchwood of myrtaceous species. Material of the locally available Kunzea ericifolia is effective in producing many seedlings. Subsequent seedling growth is enhanced with fertiliser and lime addition.
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Akhtar, Most A. "Australian native plants : a source of novel anti-inflammatory compounds." Thesis, 2018. http://hdl.handle.net/1959.7/uws:51919.

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The aim of this study was to isolate and characterise novel anti‐inflammatory compounds from native Australian plants which were important to the D’harawal Aboriginal people for antiinflammatory and related activities. A total of thirty two plants were screened for their antiinflammatory and neuroprotective activity. In chapter 2, ethanolic extracts of seventeen Eucalyptus spp. (Myrtaceae) were screened for their nitric oxide (NO) and tumour necrosis factor‐α (TNF‐α) downregulation activity and cytotoxicity in lipopolysaccharide (LPS) and interferon‐γ (IFN‐γ) activated RAW 264.7 macrophages. Extracts from seven Eucalyptus spp. demonstrated strong activity with IC50 values between 7.58 ‐ 19.77 µg/mL for NO inhibition and IC50 values for suppression of TNF‐α production were between 2.06 – 19.02 µg/mL. These extracts also showed a wide range of cytotoxicity with LC50 values between 22.34 – 236.5 µg/mL. In chapter 3, two of the highly active Eucalyptus spp. (Myrtaceae), E. viminalis and E. bosistoana were sequentially extracted and screened to find out the most active extracts which were then fractionated to identify bioactive compounds. From E. viminalis a new chromone (compound 1) has been identified together with two known compounds 8‐β‐C‐glucopyranosyl‐5,7‐dihydroxy‐2isobutylchromone and globuluside. The anti‐inflammatory and cytotoxic activities of all three compounds were evaluated against RAW 264.7 macrophage and N11 microglial cell line. In RAW 264.7 macrophage, the IC50 values for NO down regulation were 44.0, 47.0 and 37.6 µg/mL whereas the IC50 of TNF‐α suppression were 41.0, 38.3 and 43.2 µg/mL for compound 1, 8‐β‐Cglucopyranosyl‐5,7‐dihydroxy‐2‐isobutylchromone and globuluside respectively. In N11 microglia, the IC50 values for NO down regulation were 43.4, 34.1 and 21.8 µg/mL whereas the IC50 of TNF‐α suppression were 20.4, 34.3 and 19.0 µg/mL for compound 1, 8‐β‐C‐glucopyranosyl‐5,7‐dihydroxy2‐isobutylchromone and globuluside respectively. In both cell lines all of the compounds were nontoxic up to the highest concentration (36 µg/mL) tested. Oleuropeic acid which was obtained as a hydrolyzed product of compound 1 was also tested for its anti‐inflammatory activity. The NO inhibitory IC50 values were 18.7 and 10.2 µg/mL and TNF‐α inhibitory IC50 values were 21.5 and 17.0 µg/mL for oleuropeic acid against RAW 264.7 macrophage and N11 microglial cell line respectively. From E. bosistoana (chapter 3a) one known metabolite, 4‐coumaroylquinic acid was identified whose anti‐inflammatory and cytotoxic activities were evaluated in RAW 264.7 macrophage and N11 microglial cell line as well. In RAW 264.7 macrophages the compound exhibited IC50 values of 95.74 and 52.56 µg/mL for NO and TNF‐α inhibition respectively. Whereas in N11 microglia the NO and TNF‐α inhibitory IC50 values were 44.31 and 35.50 µg/mL. In both cell line the compound was nontoxic up to the highest concentration (36 µg/mL) tested. In chapter 4, ethanolic extracts of fifteen plant species from 8 different families and 11 different genera were screened for their NO and TNF‐α downregulation activity and cytotoxicity in LPS and IFN‐γ activated RAW 264.7 macrophages. Extracts from four of the plants, Syncarpia glomulifera subsp. glomulifera, Melaleuca linariifolia, Baeckea ramosissima subsp. ramosissima and B. imbricata exhibited very strong activity with IC50 values between 8.25 – 16.78 µg/mL for NO inhibition and IC50 values for suppression of TNF‐α production were between 8.31 – 23.30 µg/mL. These extracts were found less toxic compared to plants from Eucalyptus spp. with LC50 values between 52.09 – 130.0 µg/mL. xxi In chapter 5, Melaleuca linariifolia was extracted sequentially with low to high polar solvents and the sequential extracts were screened for their anti‐inflammatory activity to identify the most potent one, which was then purified using HPLC. From this plant, two known flavonoids 3, 3', 4', 5, 7pentahydroxyflavan and 3, 3’, 5, 5’, 7‐ pentahydroxyflavan were identified along with one known triterpenoid betulinic acid. The anti‐inflammatory activities as well as cytotoxicity of all three compounds were evaluated in RAW 264.7 macrophage and N11 microglial cell line. In RAW 264.7 macrophage, the IC50 values for NO down regulation were 72.81, 39.69 and 2.73 µg/mL whereas the IC50 of TNF‐α suppression were 58.88, 80.70 and 4.11 µg/mL for 3, 3', 4', 5, 7pentahydroxyflavan, 3, 3’, 5, 5’, 7‐ pentahydroxyflavan and betulinic acid respectively. In N11 microglia, the IC50 values for NO down regulation were 66.27, 58.05 and 2.23 µg/mL whereas the IC50 of TNF‐α suppression were 17.34, 21.84 and 6.76 µg/mL for 3, 3', 4', 5, 7‐pentahydroxyflavan, 3, 3’, 5, 5’, 7‐ pentahydroxyflavan and betulinic acid respectively. In chapter 6, Syncarpia glomulifera subsp. glomulifera was extracted sequentially with low to high polar solvents and the sequential extracts were screened for their anti‐inflammatory activity to identify the most potent one, which was then purified using HPLC. From this plant, two new compounds compound 6.1 and 6.4 were identified along with three known compounds tetragocarbone B (compound 6.2), sideroxylin (compound 6.3) and lumaflavanone A (compound 6.5). The anti‐inflammatory and cytotoxic activities of all five compounds were evaluated in RAW 264.7 macrophage and N11 microglial cell line. In RAW 264.7 macrophage, the IC50 values for NO down regulation were 3.91, 35.15, 2.76, 29.42 and 7.84 µg/mL whereas the IC50 of TNF‐α suppression were 16.90, 32.12, 20.80, 37.57 and 33.35 µg/mL for compound 6.1, 6.2, 6.3, 6.4 and 6.5 respectively. In N11 microglia, the IC50 values for NO down regulation were 4.52, 21.17, 3.87, 39.64 and 4.51 µg/mL whereas the IC50 of TNF‐α suppression were 6.50, 27.01, 13.66, 33.06 and 5.46 µg/mL for compound 6.1, 6.2, 6.3, 6.4 and 6.5 respectively. In chapter 7, Baeckea ramosissima subsp. ramosissima and B. imbricata leaves were extracted sequentially with low to high polar solvents and the sequential extracts were screened for their antiinflammatory activity to identify the most potent one. Sequential EtOAc extract from both plants showed highest anti‐inflammatory activity for NO inhibition (IC50 = 9.33 and 8.98 μg/mL for Baeckea ramosissima subsp. ramosissima and B. imbricata respectively) in LPS + IFN‐γ activated 264.7 RAW macrophages and subjected to HPLC for fractionation. From Baeckea ramosissima subsp. ramosissima, two known flavonoids quercetin and kaemferol were identified and evaluated for antiinflammatory and cytotoxic activities in RAW 264.7 macrophage and N11 microglial cell line. In RAW 264.7 macrophage, the IC50 values for NO down regulation were 10.95 and 9.18 µg/mL whereas the IC50 of TNF‐α suppression were 17.35 and 11.26 µg/mL for quercetin and kaemferol respectively. In N11 microglia, the IC50 values for NO down regulation were 19.71 and 16.06 µg/mL whereas the IC50 of TNF‐α suppression were 8.84 and 8.12 µg/mL for quercetin and kaemferol respectively. Isolation and characterization of other active constituents are in progress.
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43

Retallack, Mary Joy. "The potential functional diversity offered by native insectary plants to support populations of predatory arthropods in Australian vineyards." Thesis, 2019. http://hdl.handle.net/2440/120158.

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This study investigated the role that native insectary plants can play in promoting predatory arthropods, and thereby to enhance biological control of vineyard pests in Australia. I also set out to clarify if light brown apple moth (LBAM), Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae) is the main lepidopteran pest of grapevines in vineyards. Economic damage is caused to grapevines each season by pest species and E. postvittana is considered the dominant insect pest in Australian vineyards. However, recent observations suggested that species of tortricids other than E. postvittana may also act as pests. I investigated which tortricids are present in local vineyards, and whether the diversity of tortricids varied significantly among vineyards. I used molecular methods to determine the species of tortricids present in the canopies of grapevines over two growing seasons. This study confirms that E. postvittana is the most common tortricid pest in South Australian vineyards. Acropolitis rudisana (Walker) (Lepidoptera: Tortricidae), lucerne leafroller, Merophyas divulsana (Walker) (Lepidoptera: Tortricidae), and cotton tipworm, Crocidosema plebejana (Zeller) (Lepidoptera: Tortricidae) are also present in grapevine canopies but have not been reported previously. I also sought to determine if three native candidate native insectary plants, Christmas bush, Bursaria spinosa (Cav.) (Apiales: Pittosporaceae), prickly tea-tree, Leptospermum continentale (Forst. and G.Forst) (Myrtales: Myrtaceae), and wallaby grasses, Rytidosperma ssp. (DC) (Poales: Poaceae) have the capacity to support populations of predatory arthropods throughout the year, and if they may also provide habitat for economically damaging vineyards pests. Surveys were conducted in Adelaide Hills, Barossa Valley and Eden Valley vineyards over a 12-month period. The data were analysed to answer the following questions. What is the biological and functional diversity associated with each plant species? What are the features of an effective, functional native insectary plant assemblage for use in and around vineyards? What is the level of similarity and dissimilarity between the arthropod faunas of each plant species? Each plant species was found to support diverse predator species, which should attack a range of other arthropod pests across their life stages. It may also be possible to increase the functional diversity of predatory arthropods by more than three times when B. spinosa or L. continentale is incorporated into a landscape containing vineyards. Rytidosperma ssp. provides valuable complementary habitat for predatory species other than those commonly found in association with the woody perennials. When Rytidosperma ssp. are included in a viii plant assemblage with each woody plant species, this could result in an average net increase in predator morphospecies richness of at least 27%. Species distribution modelling was used to examine the potential range of each plant species under different climatic conditions. The insectary plants are naturally adapted to all of the major wine growing regions within Australia. Vineyard managers are encouraged to explore the use of B. spinosa, L. continentale and Rytidosperma ssp. as insectary plants in their vineyards. This information could help wine grape growers to manage pests like LBAM, save time and money by producing grapes with lower pest incidence, while enhancing the biodiversity of their vineyards.
Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food & Wine, 2019
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44

Njume, Collise. "Bioactive Components of Australian Native Plant species and their Potential Antidiabetic Application within the Indigenous Community." Thesis, 2020. https://vuir.vu.edu.au/41825/.

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Type 2 diabetes mellitus (T2DM), driven by overweight and obesity linked to unhealthy diets, is the fastest-growing non-communicable disease in Australia. Considering that food is an important parameter in the regulation of blood glucose response, replacing ‘junk food’ with products that are good regulators of postprandial blood glucose (PPG) may go a long way to reduce the rate of T2DM in Australia. This study was designed to develop new food products that have the potential for use as nutritional preventatives against escalating levels of T2DM within the Australian Indigenous community. Edible portions of eight Australian native plant species namely; Leucopogon parviflorus, Arthropodium strictum, Carpobrotus rossii, Rhagodia candolleana, Typha orientalis, Correa alba, Dianella revoluta and Acacia longifolia were collected from the coast of Warrnambool, Victoria Australia. The plant species were analysed for proximate, minerals, fatty acids and phenolic composition following the methods of the Association of Official Analytical Chemistry (AOAC), Inductively Coupled Plasma Spectometry (ICP), High performance liquid chromatography (HPLC) and gas chromatography/Mass spectrometry analysis (GCMS). Plant species that exhibited significantly high amounts of nutrients, antioxidants and antidiabetic polyphenols were selected for development of potential antidiabetic food preventatives. The developed food products (Acabungi flakes and crackers) were evaluated for acceptability and the cracker was further studied for stability and microbiological load. Its Glycaemic index (GI) was estimated by in-vitro enzymatic starch hydrolysis. All eight plant species were found to be sources of carbohydrates (39.7 - 65.5%), proteins (2.6 - 15.1%), fats (1 - 14.3%), total dietary fibre (1.5 - 17.2%) and contained Ca, Mg, Na and K. The species exhibited consistent antioxidant activity with phyto-components of gallic acid (GA), epigallocatechin (EPC), catechin (CH), epigallocatechingallate (EPG), dihydroquinidine (DHQ), ρ-coumaric acid (PCA) and luteolin (LT). The betacyanin, betanidin 5-O-β-glucoside (BT) was detected in R. candolleana (700 mg/kg) and C. rossi (244 mg/kg) while the alkaloid, Dihydroquinidine (DHQ) was detected in D. revoluta (101 ± 5.7 mg/kg) and T. orientalis (17 ± 7.1 mg/kg). However, not all the compounds were isolated from a single plant species and except for BT, higher quantities of components were extractable in methanol than water (P<0.05). Palmitic, oleic and linoleic acids were the dominant of 10 fatty acids detected in the native species with record quantities of 4.2 - 39%, 12.3 - 39% and <0.5 - 44% respectively. No single species had all 10 fatty acids. The cracker, with a record overall consumer acceptability of 70.5% remained stable and unchanged with no microbial growth after 35-days storage at room temperature under light and in the dark. The cracker contained significant amounts of total dietary fiber, proteins, complex carbohydrates and exhibited a low GI of 47.7. R. candolleana and A. longifolia were found to have high contents of betanin and linoleic acid respectively, two components with potentially wide industrial application. Further studies to determine the antidiabetic mechanism of action of the cracker would shed more light on its potential application.
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45

Robinson, Randall. "Natural recruitment of native forbs in the grassy ecosystems of south-eastern Australia." Thesis, 2003. https://vuir.vu.edu.au/15238/.

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As for many lowland grassy ecosystem forbs in South-eastern Australia, the recruitment dynamics of the grassland forbs Podolepis sp. 1 sensu Jeanes 1999 (Basalt Podolepis) and Bulbine semibarbata perennial form (Leek Lily)are unknown. Podolepis sp. 1 and B. semibarbata were used as models of recruitment for a range of similar forb species. In vitro trials of P. sp. 1, 6. semibarbata and an additional 16 grassy ecosystem forb species assessed germinability, germination lag time,germination speed and duration of emergence in relation to light and dark treatments. In vivo trials assessed recruitment from seed as well as field survival of several age classes of transplants, and how there were affected by soil disturbance and invertebrate herbivory over a 50-week period. In vitro germination for most species was unspecialised with germination rates greater than 50 percent. Light was a significant or neutral factor for the majority of species but negatively affected several. Survival of juvenile and semi-mature plants of P. sp. 1 and B. semibarbata were achieved in the field,along with high levels of recruitment from seed in some instances, overcoming previous lack of success in recruitment and survival of these lowland grassy ecosystem forb species. Both recruitment from seed and survival of juveniles was markedly higher in soil-disturbed plots compared with undisturbed plots. Protection from invertebrates generally enhanced survival of seed-recruited seedlings, planted juvenile plants and semi-mature plants, especially in soildisturbed plots. The possible reasons for high recruitment and survival of Podolepis sp. 1 and Bulbine semibarbata (perennial form) in soil-disturbed and invertebrate protected plots are discussed, along with the implications of these techniques for recovery and conservation of lowland grassy ecosystem forb species in South-eastern Australia.
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46

Lenz, Tanja I. "The effect of resource dynamics on invasive annual and native perennial grasses in grasslands of the mid-north of South Australia / Tanja Lenz." 2004. http://hdl.handle.net/2440/22082.

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"July 2004."
Bibliography: leaves 120-136.
vii, 136 leaves : ill. (some col.), maps ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Investigates the effects of soil moisture dynamics on the growth and interactions between invasive annual grasses and native perennial grasses in the mid-north of South Australia. At most sites annual grass abundance was positively correlated with rainfall, soil moisture after rainfall and higher soil productivity. Perennial grass abundance was negatively correlated with annual grass abundance and soil moisture after rainfall, and was weakly positively correlated with percentage summer rainfall, elevation, radiation, gravel and slope. Overall perennial grasses responded little to the environmental variables investigated, but strongly to annual grass abundance, while for annual grasses soil moisture was the driving variable.
Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004
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47

Lenz, Tanja I. "The effect of resource dynamics on invasive annual and native perennial grasses in grasslands of the mid-north of South Australia / Tanja Lenz." Thesis, 2004. http://hdl.handle.net/2440/22082.

Full text
Abstract:
"July 2004."
Bibliography: leaves 120-136.
vii, 136 leaves : ill. (some col.), maps ; 30 cm.
Investigates the effects of soil moisture dynamics on the growth and interactions between invasive annual grasses and native perennial grasses in the mid-north of South Australia. At most sites annual grass abundance was positively correlated with rainfall, soil moisture after rainfall and higher soil productivity. Perennial grass abundance was negatively correlated with annual grass abundance and soil moisture after rainfall, and was weakly positively correlated with percentage summer rainfall, elevation, radiation, gravel and slope. Overall perennial grasses responded little to the environmental variables investigated, but strongly to annual grass abundance, while for annual grasses soil moisture was the driving variable.
Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004
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48

Dorrough, Josh. "The impact of grazing and exotic invasion on the persistence of native grassland." Phd thesis, 2001. http://hdl.handle.net/1885/148807.

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49

Nielsen, Robin Christian. "A sustainability review of the NSW Native Vegetation Conservation Act 1997 and its implementation." Thesis, 2000. http://hdl.handle.net/1885/148135.

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50

Wieslaw, Jan Zielinski. "Evaluation of Wastewaters to Provide Optimum Water and Nutrient Products for Growing Turf and Native Plants." Thesis, 2015. https://vuir.vu.edu.au/29727/.

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The recent drought in South Eastern Australia and associated water restrictions led to a significant increase in the use of greywater for the watering of lawn and garden areas. There was also an emerging trend for sustainable drought resistant landscaping for which some Australian native plants were suitable. There however was an uncertainty about whether greywater was a useful source of water for plants or whether it could be harmful. This study investigated how two varieties of turf Kikuyu (Pennisetum Clandestinum) and Tall Fescue (Festuca arundinacea), and two varieties of Australian native flowers Scaly Buttons (Leptorhynchos squamatus) and Small Vanilla Lilies (Arthropodium minus) grew when watered with several different types of greywaters sourced from a bathroom shower and a laundry.
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