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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Selective hydrolysis of lipids using lipases

Adhamy, Asghar January 1989 (has links)
No description available.
2

Modelagem e simulação da impregnação do óleo de borage em membranas de poliuretano usando CO2 a alta pressão para aplicações médicas

Pereira, Verônica de Jesus January 2015 (has links)
Submitted by LIVIA FREITAS (livia.freitas@ufba.br) on 2016-05-11T12:29:08Z No. of bitstreams: 1 Pereira, V. J. _dissertação (versão final).pdf: 3722150 bytes, checksum: 811dcb81e38ab73688ed002c8e0a152b (MD5) / Approved for entry into archive by LIVIA FREITAS (livia.freitas@ufba.br) on 2016-05-11T12:30:05Z (GMT) No. of bitstreams: 1 Pereira, V. J. _dissertação (versão final).pdf: 3722150 bytes, checksum: 811dcb81e38ab73688ed002c8e0a152b (MD5) / Made available in DSpace on 2016-05-11T12:30:05Z (GMT). No. of bitstreams: 1 Pereira, V. J. _dissertação (versão final).pdf: 3722150 bytes, checksum: 811dcb81e38ab73688ed002c8e0a152b (MD5) / A impregnação de polímeros com princípios ativos de fármacos usando o dióxido de carbono a alta pressão constitui-se em uma das formas de processamento de polímeros para obtenção de sistemas de liberação controlada. A modelagem e a simulação do processo de impregnação são especialmente importantes para a previsão da viabilidade técnica do processo e a escolha das melhores condições operacionais com redução dos esforços experimentais. Nesse sentido, a presente dissertação tem como objetivo modelar e simular a impregnação de membranas de poliuretano com óleo de borage usando CO2 denso para aplicação no tratamento de feridas dérmicas. Para tanto, é crucial a descrição adequada do comportamento termodinâmico do sistema ternário CO2-óleo de borage-poliuretano a alta pressão, que não é uma tarefa trivial, pois necessita de dados de equilíbrio de fases dos sistemas binários correspondentes ainda pouco estudados na literatura. A modelagem e a simulação do processo de dessorção de CO2 em poliuretano foram realizadas utilizando-se as soluções analítica e numérica da 2ª. lei de Fick para descrição do fenômeno de transferência de massa. A determinação da quantidade máxima de CO2 sorvida no poliuretano foi obtida pela extrapolação da curva de dessorção até o tempo zero para diferentes condições de temperatura, pressão e tempo de sorção. O emprego das soluções analítica e numérica da 2ª. lei de Fick geraram resultados semelhantes tanto para o coeficiente de difusão quanto para a quantidade de CO2 sorvida pelo poliuretano. A predição do comportamento termodinâmico do óleo de borage em CO2 denso foi feita a partir da correlação de dados de solubilidade usando a equação de estado de Peng-Robinson com dois tipos de regra de mistura: a clássica e a LCVM. Devido à complexidade do sistema e a ausência de dados experimentais, as propriedades físico-químicas do óleo de borage foram estimadas por métodos de contribuição de grupos. Os resultados da correlação da solubilidade do óleo de borage em CO2 indicaram que o tipo de regra de mistura não é o fator determinante vi para o bom ajuste do modelo aos pontos experimentais, mas sim a quantidade de parâmetros ajustáveis utilizados. Observou-se que apenas a regra de mistura clássica com dois parâmetros ajustáveis dependentes da temperatura é capaz de descrever satisfatoriamente o comportamento termodinâmico desse sistema. A modelagem do equilíbrio de fases do sistema ternário foi feita através da predição do coeficiente de partição do óleo de borage entre as fases polimérica e fluida, a partir dos dados experimentais dos sistemas binários, usando-se a teoria do equilíbrio de fases e modelos específicos. Observou-se que, apesar da escassez de dados de equilíbrio de fases para os sistemas binários, é possível fazer uma avaliação qualitativa satisfatória a partir do cálculo preditivo do coeficiente de partição do óleo de borage. Os resultados mostraram que a ordem de grandeza do coeficiente de partição calculado é a mesma dos valores obtidos a partir dos dados experimentais de impregnação.
3

Oxidative stability of stripped and non-stripped borage and evening primrose oils and their oil-in-water emulsions /

Khan, Muhammad Ahmad, January 1999 (has links)
Thesis (M.Sc.), Memorial University of Newfoundland, 1999. / Restricted until June 2000. Bibliography: leaves [126]-142.
4

Characterization of natural antioxidants of meals of borage and evening primrose /

Wettasinghe, Mahinda, January 1999 (has links)
Thesis (Ph.D.)--Memorial University of Newfoundland, 1999. / Restricted until November 2000. Bibliography: leaves 272-302.
5

Towards Development of Imidazolinone Herbicide Resistant Borage (Borago officinalis)

2015 February 1900 (has links)
Borage (Borago officinalis) is an annual herb plant for culinary and medicinal uses. Due to a high level of gamma-linolenic acid (GLA) in its seed oil and the health-related benefits of GLA, borage is commercially cultivated. However, a herbicide-resistant variety has not yet been developed for effective weed management in borage farming. Thus, this thesis aimed to create, identify and characterize ethyl methanesulfonate (EMS) induced borage mutants for herbicide imidazolinone resistance. An EMS-mutagenized borage population was generated by using a series of concentrations of EMS to treat M1 seeds. After screening M2 borage plants with the herbicide, tolerant plants were selected, self-pollinated and grown to their maturity. The offsprings were subjected to herbicide screening again to confirm the phenotype, resulting in identification of two genetically stable imidazolinone-resistant lines. Two acetohydroxyacid synthase (AHAS) genes, AHAS1 and AHAS2, involved in the imidazolinone resistance were isolated and sequenced from both mutant (resistant) and wild type (susceptible) borage plants. Comparison of these AHAS sequences revealed that a single nucleotide substitution occurred in the AHAS1 resulting in an amino acid change from serine (S) in the susceptible plant to asparagine (N) in the first resistant line. The similar substitution was later found in the AHAS2 of the second resistant line. A KASP marker was developed for the AHAS1 mutation to differentiate the homozygous susceptible, homozygous and heterozygous resistant borage plants for the breeding purpose. The in vitro assay showed homozygous resistant borage containing the AHAS1 mutation could retain significantly higher AHAS activity than susceptible borage across different imazamox concentrations. The herbicide dose response test showed that the resistant line with the AHAS1 mutation was tolerant to four times the field applied concentration of the “Solo” herbicide.
6

Impregnação/deposição de agentes bioativos em curativos poliméricos usando CO2 supercrítico

Silva, Cinara Vasconcelos da 23 February 2018 (has links)
Submitted by Cinara Silva (cinarasilva@ufba.br) on 2018-08-27T14:09:39Z No. of bitstreams: 1 Tese final.pdf: 8464968 bytes, checksum: c7808d54e53ed142b3589db96c66a6a0 (MD5) / Rejected by Vanessa Reis (vanessa.jamile@ufba.br), reason: Documento incompleto. Necessidade de apresentar folha de aprovação com assinatura dos membros da banca e elementos informativos como logomarca da instituição UFBA. on 2018-08-27T14:17:59Z (GMT) / Submitted by Cinara Silva (cinarasilva@ufba.br) on 2018-08-29T15:56:22Z No. of bitstreams: 1 Tese Final - CINARA.pdf: 10065670 bytes, checksum: d646a92fe145d1a1b098aa8828c6d6c4 (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2018-08-29T16:19:12Z (GMT) No. of bitstreams: 1 Tese Final - CINARA.pdf: 10065670 bytes, checksum: d646a92fe145d1a1b098aa8828c6d6c4 (MD5) / Made available in DSpace on 2018-08-29T16:19:12Z (GMT). No. of bitstreams: 1 Tese Final - CINARA.pdf: 10065670 bytes, checksum: d646a92fe145d1a1b098aa8828c6d6c4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / O presente trabalho visou estudar a viabilidade de incorporação de agentes bioativos em curativos poliméricos utilizando dióxido de carbono supercrítico (CO2). Foram utilizados dois curativos comerciais: Foam Dressing (poliuretano) e Promogran® (colágeno e celulose regenerada oxidada). Como bioativos, foram testados o óleo de borage e o extrato de jambu. Foram realizados ensaios de sorção de CO2 supercrítico nessas matrizes poliméricas sob diferentes condições, de modo a potencializar a incorporação de agentes bioativos. Isto pode ser útil para futuros trabalhos na área de impregnação/deposição de agentes bioativos em curativos de espuma, já que é o primeiro estudo com estes tipos de material (curativos e bioativos) nestas condições experimentais. Os resultados mostraram que a melhor condição de sorção para ambos os polímeros foi obtida na temperatura de 308,15 K e densidade do CO2 igual a 850 kg.m-3. O melhor rendimento de impregnação para o óleo de borage em poliuretano (11,8 % m/m) ocorreu nessa mesma densidade do CO2 e na temperatura de 328,15 K. Para o extrato de jambu, o maior rendimento de incorporação na matriz de colágeno e celulose ocorreu nas condições de melhor sorção e com adição de etanol como cossolvente (6,4% m/m). Os resultados obtidos mostraram que a etapa controladora do processo de impregnação/deposição (SSI/SSD) é o equilíbrio de fases e apontam para a possível viabilidade técnica da impregnação de bioativos de origem natural em curativos poliméricos. / ABSTRACT The present work aimed to study the feasibility of incorporation of bioactive agents into polymeric dressings using supercritical carbon dioxide (CO2). Two commercial dressings were investigated: Foam Dressing (polyurethane) and Promogran (collagen and oxidized regenerated cellulose). The bioactives investigated were borage oil and jambu extract. Assays of supercritical CO2 sorption into these polymeric dressings were carried out under different conditions in order to enhance the incorporation of these bioactive agents into the polymer matrices. This can be useful for future works on impregnation/deposition area of bioactive agents in foam dressings, since the study is the first one using these materials (dressings and bioactives) at these experimental conditions. The results showed that the best sorption condition for both polymers was obtained at 308 K and CO2 density equal to 850 kg.m-3. The best impregnation/deposition yield for borage oil and polyurethane (11.8 % w/w) occurred also at this same CO2 density and temperature at 328,15 K. In the case of jambu extract, the highest incorporation yield into the collagen and cellulose matrix occurred under the conditions of highest sorption with the addition of ethanol as a cosolvent (6,4 % w/w). The results showed that SSI/SSD is controlled by phase equilibrium phenomenon and point towards the technical feasibility of this process.
7

EMPREGO DO ÓLEO DE Borago officinalis L. NO DESENVOLVIMENTO DE FORMULAÇÕES SEMISSÓLIDAS E NANOCÁPSULAS POLIMÉRICAS DESTINADAS AO TRATAMENTO TÓPICO DE DOENÇAS INFLAMATÓRIAS DA PELE / EMPLOYMENT OF Borago officinalis L. OIL IN THE DEVELOPMENT OF FORMULATIONS SEMISOLIDS AND NANOCAPSULES POLYMER INTENDED FOR TOPICAL TREATMENT OF INFLAMMATORY DISEASES OF THE SKIN

Weber, Julia 28 April 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed to obtain semisolids formulations and lipid core nanocapsules containing borage oil associated or not with betamethasone dipropionate, for their application in the treatment of atopic dermatitis. A gel-cream containing borage oil was prepared and presented satisfactory results for performed tests (pH, spreadability and viscosity suitable for topical application). The in vivo assay showed topical anti-inflammatory action of the oil in rats. Additionally, nanocapsule suspensions containing borage oil and betamethasone dipropionate were prepared by interfacial deposition of preformed polymer method and were characterized. The colloidal suspensions, showed a slightly acid pH (6.0-6.2), nanosized particles (180-210 nm), with a low polydispersity index (<0.1), negative zeta potential (-9 to -16 mV), betamethasone content was close to theoretical and encapsulation efficiency of approximately 100%. After 15 days of storage at room temperature, only zeta potential. Photodegradation study of of betamethasone dipropionate using UVC light was performed. It was observed a protection against photodegradation conferred by the nanostructured drug delivery systems. The in vitro release study of betamethasone dipropionate from nanocapsule suspensions demonstrated the ability of nanostructures to decrease the drug release. These nanostructures were incorporated into hydrogels (Carbopol® Ultrez and Cellosize®). The hydrogels were evaluated and showed acidic pH, nanosized particle, betamethasone content near to theoretical (0.5 mg / g) and pseudoplastic behavior (Herschel-Bulkley model). In vitro release study of betamethasone dipropionate from the hydrogels demonstrated a reduced release of the drug in the different analysis times, as compared with hydrogels containing the non-associated drug. The in vivo anti-inflammatory assay showed the anti-inflammatory activity of the hydrogels containing the nanostructures, which can demonstrate the drug and the oil activity when combined with polymeric nanocapsules. / Esse trabalho buscou obter formulações semissólidas e nanocápsulas de núcleo lipídico contendo o óleo de borragem associado ou não ao dipropionato de betametasona, visando sua aplicação no tratamento da dermatite atópica. Uma formulação semissólida do tipo creme-gel contendo o óleo de borragem foi preparada e apresentou resultados satisfatórios para os testes empregados (pH, espalhabilidade e viscosidade adequadas para aplicação tópica). O ensaio in vivo realizado em ratos Wistar evidenciou a ação anti-inflamatória tópica do óleo. Adicionalmente, suspensões de nanocápsulas foram preparadas pelo método de deposição interfacial de polímero pré-formado, contendo o óleo de borragem e dipropionato de betametasona, as quais foram caracterizadas em relação ao tamanho médio de partículas, índice de polidispersão (PdI), potencial zeta, microscopia de transmissão eletrônica, pH, teor de fármaco e eficiência de encapsulamento. As formulações apresentaram pH levemente ácido (6,0-6,2), partículas de tamanho nanométrico (180-210 nm), baixo índice de polidispersão (< 0,1), potencial zeta negativo (-9 a -16 mV), teor de betametasona próximo ao teórico e eficiência de encapsulamento de, aproximadamente, 100%. No período de 15 dias de armazenamento, a temperatura ambiente, apenas o potencial zeta. O estudo de fotodegradação do dipropionato de betametasona frente à luz UVC foi realizado e evidenciou a relevância dos sistemas nanoestruturados na proteção do fármaco. O estudo de liberação in vitro a partir das suspensões demonstrou a capacidade das nanocápsulas em reduzir a liberação do fármaco. As nanoestruturas foram incorporadas em hidrogéis (Carbopol® Ultrez e Cellosize®), os quais foram avaliados quanto ao pH, tamanho de partículas, espalhabilidade, propriedades reológicas e teor de fármaco. Os hidrogéis apresentaram pH ácido, tamanho de partícula nanométrico, teor de betametasona próximo ao teórico (0,5 mg/g) e comportamento pseudoplástico (modelo Herschel-Bulkley). No estudo de liberação in vitro do dipropionato de betametasona a partir dos hidrogéis verificou-se uma liberação menor do fármaco nos diferentes tempos de análise em comparação com os hidrogéis contendo o fármaco não associado. O ensaio in vivo para avaliar a atividade anti-inflamatória dos hidrogéis contendo as nanoestruturas foi também realizado, sendo possível comprovar a atividade do fármaco e do óleo quando associados à nanocápsulas poliméricas.
8

Habitat manipulation to enhance biological control of light brown apple moth (Epiphyas Postvittana)

Begum, Mahmuda January 2004 (has links)
Trichogramma carverae Oatman and Pinto is mass-released for biological control of the leafroller pest, light brown apple moth, Epiphyas postvittana (Walker) in Australian vineyards. Parasitoid performance can, however, be constrained by a lack of suitable adult food and no information is available on the effect of nectar on the parasitism and longevity of T. carverae. To address this, the effect of alyssum, Lobularia maritima (L.) flowers on E. postvittana parasitism was studied in a vineyard experiment with and without releases of T. carverae. Egg parasitoid activity was assessed with E. postvittana egg �sentinel cards� and no parasitism was recorded in plots without T. carverae releases. Where T. carverae were released, there was no significant enhancement of parasitism by the presence of L. maritima flowers. Three hypotheses were subsequently tested to account for the lack of an effect: (i) T. carverae does not benefit from L. maritima nectar, (ii) T. carverae was feeding on nectar from other flowering plants (weeds) present in the vineyard, (iii) T. carverae was feeding on sugars from ripe grapes. A growth-cabinet experiment using potted L. maritima plants with and without flowers did not support hypothesis one. No parasitism was recorded after day two for T. carverae caged without flowers whilst parasitism occured until day eight in the presence of flowers. A laboratory experiment with common vineyard weeds (Trifolium repens, Hypochoeris radicata, Echium plantagineum) as well as L. maritima did not support hypothesis one but gave partial support to hypothesis two. Survival of T. carverae was enhanced to a small but statistically significant extent in vials with intact flowers of L. maritima, white clover (T. repens) and catsear (H. radicata) but not in vials with flowering shoots of these species from which flowers and flowering buds had been removed. Paterson�s curse (E. plantagineum) flowers had no effect on T. carverae survival. In a laboratory study, punctured grapes significantly enhanced T. carverae survival compared with a treatment without grapes, supporting hypothesis three. Trichogramma carverae performance in the field experiment was probably also constrained by relatively cool and wet weather. Further work on the enhancement of T. carverae efficacy by L. maritima and other carbohydrate sources is warranted. Greenhouse and field experiments were conducted to investigate whether T. carverae benefit from different groundcover plant species. Ten T. carverae adults (<24h after eclosion) were caged with different groundcover species and a control with no plant materials. Epiphyas postvittana egg sentinel cards were used to measure parasitism and longevity was recorded visually. Survival and realised parasitism of T. carverae was significantly higher in L. maritima than in Brassica juncea, Coriandrum sativum, shoots of these species from which flowers had been removed and nil control treatments. A similar experiment with Fagopyrum esculentum (with- and without-flowers) and a control treatment showed that survival was significantly higher in intact F. esculentum than in without-flower and control treatments. There was no significant treatment effect on parasitism in the early stages of that experiment, though parasitism was recorded in the presence of F. esculentum flowers for 12 days, compared with 6 days in other treatments. Higher parasitism was observed in intact Borago officinalis than in the flowerless shoot, water only and no plant material control treatments in a third experiment. There was no significant treatment effect on parasitism. Fitted exponential curves for survival data differed significantly in curvature in the first, second and third experiments but the slope was a non-significant parameter in the second and third experiments. In a second series of laboratory experiments, one male and one female T. carverae were caged with groundcover species to investigate male and female longevity and daily fecundity. Both male and female longevity in F. esculentum and L. maritima treatments were significantly higher than on shoots of these species from which flowers had been removed, and than in the control treatments. Daily fecundity was significantly greater in the intact L. maritima treatment than in all other treatments. Fitted exponential curves for daily fecundity differed significantly in position and slope but not in curvature. There was no significant treatment effect on longevity or parasitism when a male and female were caged with intact B. juncea, B. officinalis or without-flower of these species, nor in the treatment with no plant materials. No parasitism was observed in a survey of naturally occurring egg parasitoids on two sites close to Orange and Canowindra in New South Wales, illustrating the importance of mass releases of T. carverae in biological control of E. postvittana. In an experiment on the Canowindra site, parasitism was significantly higher on day one and day two after T. carverae release when with-flower treatments were compared with without-flower treatments. Parasitism was significantly higher in the F. esculentum treatment than in C. sativum, L. maritima, vegetation without-flowers and control treatments on these dates. On day five, parasitism was higher in C. sativum than in all other treatments. There was no significant increase in parasitism in a second experiment conducted on the Orange site. Coriandrum sativum, F. esculentum and L. maritima appear to be suitable adult food sources for T. carverae and offer some scope for habitat manipulation in vineyards The adults of many parasitoid species require nectar for optimal fitness but very little is known about flower recognition. Flight cage experiments showed that the adults of T. carverae benefited from L. maritima bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on non-white flowers were no greater than when the parasitoids were caged on L. maritima shoots from which flowers had been removed. The possibility that differences between L. maritima cultivars were due to factors other than flower colour, such as nectar quality, was excluded by dyeing white L. maritima flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed L. maritima flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower colour appears, therefore, to be a critical factor in the choice of plants used to enhance biological control, and is likely to also be a factor in the role parasitoids play in structuring invertebrate communities. Provision of nectar producing plants to increase the effectiveness of biological control is one aspect of habitat manipulation, but care needs to be taken to avoid the use of plant species that may benefit pest species. Greenhouse experiments were conducted to investigate whether the adult E. postvittana and larvae benefit from nectar producing groundcover species. Newly emerged E. postvittana adults were caged with different groundcover species and a honey-based artificial adult diet. The longevity of male and female E. postvittana when caged with shoots of borage (B. officinalis) and buckwheat (F. esculentum) bearing flowers was as long as when fed a honey-based artificial diet. This effect was not evident when caged with shoots of these plants from which flowers had been removed. Longevity was significantly lower than in the artificial diet treatment when caged with coriander (C. sativum) or alyssum (L. maritima) irrespective of whether flowers were present or not. There was no significant treatment effect on the lifetime fecundity of E. postvittana. A second experiment with mustard (B. juncea) (with- and without-flowers), water only and honey-based artificial adult diet showed no significant treatment effects on the longevity of male and female E. postvittana or on the lifetime fecundity of E. postvittana. The anomalous lack of a difference between the water and honey-based diet treatments precludes making conclusions on the value of B. juncea for E. postvittana. Two greenhouse experiments were conducted to evaluate the effects of groundcover species on the larval development of E. postvittana. In the first experiment, larval mortality was significantly higher in C. sativum, and L. maritima than in B. juncea, B. officinalis and white clover (T. repens) a known host of E. postvittana. Coriandrum sativum and L. maritima extended the larval period. In B. juncea and B. officinalis, mortality did not differ from that in T. repens. In F. esculentum, larval mortality was significantly higher than in T. repens. A short larval period was observed on B. juncea, B. officinalis and F. esculentum. Fitted exponential curves for larval mortality differed significantly in curvature between plant treatments. Similarly, successful pupation was significantly lower in C. sativum, F. esculentum and L. maritima than in T. repens. The percentage of successful pupation in B. juncea and B. officinalis did not differ from F. esculentum and T. repens. Fitted exponential curves for pupation differed significantly in curvature. A similar trend was observed in a second experiment with potted plants. The overall results suggest that C. sativum and L. maritima denied benefit to E. postvittana adults and larvae, so could be planted as vineyard groundcover with minimal risk of exacerbating this pest. Overall results suggest that T. carverae require nutrients to reach their full reproductive potential and flowers provide such nutrients. Lobularia maritima and C. sativum may be considered �selective food plants� for T. carverae whereas F. esculentum appears to be a �non-selective food plant�; both T. carverae and E. postvittana benefited from it. Fruits such as grapes can be used as food resources in habitat manipulation and this merits further research. This result also suggests that within species flower colour is an important factor for flower selection in habitat manipulation.
9

Habitat manipulation to enhance biological control of light brown apple moth (Epiphyas Postvittana)

Begum, Mahmuda January 2004 (has links)
Trichogramma carverae Oatman and Pinto is mass-released for biological control of the leafroller pest, light brown apple moth, Epiphyas postvittana (Walker) in Australian vineyards. Parasitoid performance can, however, be constrained by a lack of suitable adult food and no information is available on the effect of nectar on the parasitism and longevity of T. carverae. To address this, the effect of alyssum, Lobularia maritima (L.) flowers on E. postvittana parasitism was studied in a vineyard experiment with and without releases of T. carverae. Egg parasitoid activity was assessed with E. postvittana egg �sentinel cards� and no parasitism was recorded in plots without T. carverae releases. Where T. carverae were released, there was no significant enhancement of parasitism by the presence of L. maritima flowers. Three hypotheses were subsequently tested to account for the lack of an effect: (i) T. carverae does not benefit from L. maritima nectar, (ii) T. carverae was feeding on nectar from other flowering plants (weeds) present in the vineyard, (iii) T. carverae was feeding on sugars from ripe grapes. A growth-cabinet experiment using potted L. maritima plants with and without flowers did not support hypothesis one. No parasitism was recorded after day two for T. carverae caged without flowers whilst parasitism occured until day eight in the presence of flowers. A laboratory experiment with common vineyard weeds (Trifolium repens, Hypochoeris radicata, Echium plantagineum) as well as L. maritima did not support hypothesis one but gave partial support to hypothesis two. Survival of T. carverae was enhanced to a small but statistically significant extent in vials with intact flowers of L. maritima, white clover (T. repens) and catsear (H. radicata) but not in vials with flowering shoots of these species from which flowers and flowering buds had been removed. Paterson�s curse (E. plantagineum) flowers had no effect on T. carverae survival. In a laboratory study, punctured grapes significantly enhanced T. carverae survival compared with a treatment without grapes, supporting hypothesis three. Trichogramma carverae performance in the field experiment was probably also constrained by relatively cool and wet weather. Further work on the enhancement of T. carverae efficacy by L. maritima and other carbohydrate sources is warranted. Greenhouse and field experiments were conducted to investigate whether T. carverae benefit from different groundcover plant species. Ten T. carverae adults (<24h after eclosion) were caged with different groundcover species and a control with no plant materials. Epiphyas postvittana egg sentinel cards were used to measure parasitism and longevity was recorded visually. Survival and realised parasitism of T. carverae was significantly higher in L. maritima than in Brassica juncea, Coriandrum sativum, shoots of these species from which flowers had been removed and nil control treatments. A similar experiment with Fagopyrum esculentum (with- and without-flowers) and a control treatment showed that survival was significantly higher in intact F. esculentum than in without-flower and control treatments. There was no significant treatment effect on parasitism in the early stages of that experiment, though parasitism was recorded in the presence of F. esculentum flowers for 12 days, compared with 6 days in other treatments. Higher parasitism was observed in intact Borago officinalis than in the flowerless shoot, water only and no plant material control treatments in a third experiment. There was no significant treatment effect on parasitism. Fitted exponential curves for survival data differed significantly in curvature in the first, second and third experiments but the slope was a non-significant parameter in the second and third experiments. In a second series of laboratory experiments, one male and one female T. carverae were caged with groundcover species to investigate male and female longevity and daily fecundity. Both male and female longevity in F. esculentum and L. maritima treatments were significantly higher than on shoots of these species from which flowers had been removed, and than in the control treatments. Daily fecundity was significantly greater in the intact L. maritima treatment than in all other treatments. Fitted exponential curves for daily fecundity differed significantly in position and slope but not in curvature. There was no significant treatment effect on longevity or parasitism when a male and female were caged with intact B. juncea, B. officinalis or without-flower of these species, nor in the treatment with no plant materials. No parasitism was observed in a survey of naturally occurring egg parasitoids on two sites close to Orange and Canowindra in New South Wales, illustrating the importance of mass releases of T. carverae in biological control of E. postvittana. In an experiment on the Canowindra site, parasitism was significantly higher on day one and day two after T. carverae release when with-flower treatments were compared with without-flower treatments. Parasitism was significantly higher in the F. esculentum treatment than in C. sativum, L. maritima, vegetation without-flowers and control treatments on these dates. On day five, parasitism was higher in C. sativum than in all other treatments. There was no significant increase in parasitism in a second experiment conducted on the Orange site. Coriandrum sativum, F. esculentum and L. maritima appear to be suitable adult food sources for T. carverae and offer some scope for habitat manipulation in vineyards The adults of many parasitoid species require nectar for optimal fitness but very little is known about flower recognition. Flight cage experiments showed that the adults of T. carverae benefited from L. maritima bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on non-white flowers were no greater than when the parasitoids were caged on L. maritima shoots from which flowers had been removed. The possibility that differences between L. maritima cultivars were due to factors other than flower colour, such as nectar quality, was excluded by dyeing white L. maritima flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed L. maritima flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower colour appears, therefore, to be a critical factor in the choice of plants used to enhance biological control, and is likely to also be a factor in the role parasitoids play in structuring invertebrate communities. Provision of nectar producing plants to increase the effectiveness of biological control is one aspect of habitat manipulation, but care needs to be taken to avoid the use of plant species that may benefit pest species. Greenhouse experiments were conducted to investigate whether the adult E. postvittana and larvae benefit from nectar producing groundcover species. Newly emerged E. postvittana adults were caged with different groundcover species and a honey-based artificial adult diet. The longevity of male and female E. postvittana when caged with shoots of borage (B. officinalis) and buckwheat (F. esculentum) bearing flowers was as long as when fed a honey-based artificial diet. This effect was not evident when caged with shoots of these plants from which flowers had been removed. Longevity was significantly lower than in the artificial diet treatment when caged with coriander (C. sativum) or alyssum (L. maritima) irrespective of whether flowers were present or not. There was no significant treatment effect on the lifetime fecundity of E. postvittana. A second experiment with mustard (B. juncea) (with- and without-flowers), water only and honey-based artificial adult diet showed no significant treatment effects on the longevity of male and female E. postvittana or on the lifetime fecundity of E. postvittana. The anomalous lack of a difference between the water and honey-based diet treatments precludes making conclusions on the value of B. juncea for E. postvittana. Two greenhouse experiments were conducted to evaluate the effects of groundcover species on the larval development of E. postvittana. In the first experiment, larval mortality was significantly higher in C. sativum, and L. maritima than in B. juncea, B. officinalis and white clover (T. repens) a known host of E. postvittana. Coriandrum sativum and L. maritima extended the larval period. In B. juncea and B. officinalis, mortality did not differ from that in T. repens. In F. esculentum, larval mortality was significantly higher than in T. repens. A short larval period was observed on B. juncea, B. officinalis and F. esculentum. Fitted exponential curves for larval mortality differed significantly in curvature between plant treatments. Similarly, successful pupation was significantly lower in C. sativum, F. esculentum and L. maritima than in T. repens. The percentage of successful pupation in B. juncea and B. officinalis did not differ from F. esculentum and T. repens. Fitted exponential curves for pupation differed significantly in curvature. A similar trend was observed in a second experiment with potted plants. The overall results suggest that C. sativum and L. maritima denied benefit to E. postvittana adults and larvae, so could be planted as vineyard groundcover with minimal risk of exacerbating this pest. Overall results suggest that T. carverae require nutrients to reach their full reproductive potential and flowers provide such nutrients. Lobularia maritima and C. sativum may be considered �selective food plants� for T. carverae whereas F. esculentum appears to be a �non-selective food plant�; both T. carverae and E. postvittana benefited from it. Fruits such as grapes can be used as food resources in habitat manipulation and this merits further research. This result also suggests that within species flower colour is an important factor for flower selection in habitat manipulation.

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