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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.
81

Das Blüte-Bestäuber-Netz auf Brachflächen : biozönologische Untersuchung zur Bedeutung von Brachen in einer intensiv genutzten Agrarlandschaft

Hahn, Robert January 2002 (has links)
In der vorliegenden Dissertation wird die Bedeutung von Brachen für Artenvielfalt und Stabilität von Blüte-Bestäuber-Nahrungsnetzen in agrarisch genutzten Landschaften anhand ausgewählter blütenbesuchender Insektengruppen (Syrphidae, Lepidoptera) untersucht. Die Freilandarbeiten fanden von 1998-2000 im Raum der Feldberger Seenlandschaft, Mecklenburg-Vorpommern, statt. Es werden die beiden Hauptnahrungsquellen Nektar und Pollen betrachtet, dabei fanden Untersuchungen zur Intensität der Blüte-Bestäuber-Interaktion auf Stilllegungsflächen, zum flächenbezogenen quantitativen Nektarangebot im Jahresverlauf, zur individuellen Pollennutzung bei Syrphiden und zur Breite und Überlappung der Nahrungsnischen bei den dominanten Arten Episyrphus balteatus, Metasyrphus corollae, Syritta pipiens und Sphaerophoria scripta statt.<br /> <br /> Im Ergebnis zeigt sich eine hohe Bedeutung der Brachflächen für die Stabilität des Blüte-Bestäuber-Netzes, während die Diversität von anderen, eher landschaftsbezogenen Faktoren abhängig ist. / This dissertation examines the importance of fallow land for the diversity and stability of pollination webs in agricultural landscapes as exemplified by selected groups of anthophilous insects (syrphidae and lepidoptera). The field studies were carried out between 1998 and 2000 in the Feldberg lakeland area in the north-east German State of Mecklenburg-Western Pomerania. Observations were made of nectar and pollen as the two main sources of food. Studies were conducted into the intensity of plant-pollinator interaction in set-aside areas, the site-specific quantity of nectar available during the vegetation period and the individual pollen intake of syrphid flies. Different methods were employed to establish the breadth of the trophic niches among the predominant species (Episyrphus balteatus, Metasyrphus corollae, Syritta pipiens and Sphaerophoria scripta) and the extent to which they overlapped. <br /> <br /> The studies showed that, while fallow land is very important for the stability of plant-pollinator food webs, their diversity depends on other factors that are more closely related to the landscape.
82

Evolutionary genetics and ecology of water use efficiency ([delta]¹³C) in Ipomopsis agregata and Arabidopsis thaliana

Kenney, Amanda Marie 31 January 2012 (has links)
My dissertation research investigates the genetic architecture and evolutionary significance of physiological variation in two wildflower species, Ipomopsis aggregata and Arabidopsis thaliana. In particular, my work focuses on water use efficiency (WUE), a critical physiological trait that dictates plant growth and performance in resource-limited environments. I used a combination of quantitative trait loci (QTL) mapping, field selection experiments, and classic quantitative genetics to investigate 1) the genetic architecture of water use efficiency and flowering time, 2) patterns of natural selection on water use efficiency, flowering time, and other ecological traits in I. aggregata, and 3) additive genetic variation, genetic correlations, and selection on water use efficiency, flowering time, and plasticity to drought in Arabidopsis thaliana. Using an Ipomopsis aggregata genetic mapping population, I identified four QTL underlying WUE, three QTL-QTL epistatic interactions, and evidence for a possible QTL x cytoplasmic interaction affecting WUE. I found a similar genetic architecture underlying flowering time, with four main effect QTLs that all adjacently localized to the same linkage groups as WUE, and three QTL-QTL epistatic interactions, which occur between the same chromosome pairs as the WUE interactions. The combined main and interactive effects explain 35% and 40% of the phenotypic variation in WUE and flowering time, respectively. The adjacent localization suggests a possible role for the evolution of co-inheritance or, if the true QTL positions actually overlap, a possible role for pleiotropy underlying the phenotypic correlation between WUE and flowering time. Additionally, these results suggest epistasis is a significant factor affecting phenotypic variation in nature. In a reciprocal transplant and water addition experiment, I demonstrated variable natural selection on WUE, flowering time, and nectar production in I. aggregata across elevation/habitat and differential water availability. At low elevation in the water addition treatment, natural selection favors early flowering and greater nectar sugar concentration, while dry conditions favor high WUE and early flowering time. At high elevation, where the growing season is shorter and drier, selection favors early flowering regardless of water addition. These results suggest natural selection on ecophysiological and floral traits varies with resource availability (e.g. water availability and pollinator visitation). Using data from a glasshouse experiment involving a global panel of accessions of Arabidopsis thaliana, I demonstrated strong positive genetic correlation between WUE and flowering time, as well as selection for low WUE and early flowering under experimental season-ending drought. Finally, I found significant genetic variation in plasticity as well as selection favoring greater WUE plasticity under drought, indicating plasticity to drought is adaptive in A. thaliana. / text
83

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.
84

Produção e distribuição temporal de néctar em área de regeneração de cerrado: implicações na polinização e estrutura de comunidade de abelhas / Production and temporal distribution of nectar in regeneration area of the Brazilian savanna: implications on the pollination and bees community structure

Elisa Pereira Queiroz 22 June 2015 (has links)
A disponibilidade e distribuição espaço-temporal do néctar nos diferentes tipos vegetacionais está relacionada a diversos fatores. Em espécies nectaríferas, o néctar é o recurso principal disponibilizado aos visitantes florais e sua produção pode determinar o sucesso no fluxo de pólen entre indivíduos na população. Nesse estudo, os objetivos foram: (i) avaliar se o display floral e seus caracteres morfológicos estão associados à produção do néctar; (ii) verificar se a distribuição do néctar é concentrada ou uniformemente distribuída ao longo do ano e; (iii) como a produção do néctar atua na atração dos visitantes florais e na deposição intra e interespecífica de pólen no estigma em espécies de plantas nectaríferas. O estudo foi feito em vegetação de cerrado na Estação Ecológica de Jataí (EEJ), localizada em Luís Antônio, São Paulo. Na EEJ, nós demarcamos duas transeções de 500 m por 10 m de cada lado. As transeções foram percorridas quinzenalmente no período de agosto de 2013 a julho de 2014 e para cada espécie de planta nectarífera em floração, nós contamos o número de indivíduos e de flores produzidas/indivíduo (display floral). Nós encontramos que há interação significativa entre o tamanho e a forma da flor na produção do néctar (F = 40,48, p < 0,0001). Nós observamos que quanto maior o número médio de óvulos de uma dada espécie, maior a produção média de néctar por flor (Rs = 0,58; p < 0,05). Encontramos que a razão pólen intraespecífico/pólen total depositado no estigma das flores foi influenciada negativamente pela abundância das abelhas (t= -3,930; p= 0,005). Nós observamos um nível intermediário de especialização (H2 = 0,412) quando analisamos a interação entre as espécies nectaríferas e as abelhas visitantes por meio de observação direta e mais especializado quando analisamos a interação por meio dos grãos de pólen depositados no corpo das abelhas (H2 = 0,62). Nós encontramos uma interação altamente especializada quando avaliamos os grãos de pólen depositados nos estigmas (H2 = 0,943). Nós corroboramos as nossas hipóteses de que a produção e distribuição do néctar na comunidade estão associadas ao número de flores disponíveis e à morfologia floral das espécies nectaríferas e que as plantas que produzem mais flores e um maior volume de néctar, apresentaram mais óvulos e atraem um maior número de abelhas visitantes e consequentemente apresentam uma maior deposição polínica nos estigmas / The availability and the spatial and temporal distribution of nectar in different types of vegetation are related to several factors. In nectariferous species, nectar is the main resource available to floral visitors and its production can determine a successful pollen flow between individuals in the population. The present study aimed to: (i) assess whether the floral display and its morphological traits are associated with nectar production; (ii) verify whether the distribution of nectar is concentrated or evenly distributed throughout the year and; (iii) analyze the influence of nectar production in attracting floral visitors and on intra and interspecific deposition of pollen on the stigma in nectariferous plant species. The study was conducted in cerrado in the Jataí Ecological Station (EEJ), located in Luís Antônio, São Paulo State. Inside the EEJ, two transects measuring 500 m x 10 m were delimited. The transects were run every two weeks from August 2013 to July 2014 and the number of individuals and flowers produced/individual (floral display) were counted for each species of nectariferous plant at flowering. There was a significant interaction between the size and shape of the flower for nectar production (F = 40.48, p < 0.0001). The higher the average number of ovules of a given species, the greater the average production of nectar per flower (Rs = 0.58; p < 0.05). Also, the ratio intraspecific pollen/total pollen deposited on the stigma of flowers was negatively affected by the abundance of bees (t= -3.930; p= 0.005). An intermediate level of specialization (H2 = 0.412) was found when analyzing the interaction between nectariferous species and visiting bees through direct observation and a more specialized level when analyzing the interaction by means of pollen grains deposited on the body of bees (H2= 0.62). In turn, considering the pollen grains deposited on stigmas, a highly specialized interaction was recorded (H2= 0.943). Our following hypotheses were confirmed: the production and distribution of nectar in the community are associated with the number of available flowers and with floral morphology of the nectariferous species and plants producing more flowers and a greater volume of nectar present more ovules and attract a higher number of visiting bees and thus show a greater deposition of pollen on stigmas
85

Parasitas de interações e a coevolução de mutualismos / Interaction parasites and the coevolution of mutualisms

Flávia Maria Darcie Marquitti 21 August 2015 (has links)
Mutualismos são interações em que os parceiros se exploram reciprocamente com benefícios líquidos para ambos os indivíduos que interagem. Sistemas mutualistas multiespecíficos podem ser descritos como redes de interação, tais como aquelas formadas por sistemas de polinização, dispersão de sementes, estações de limpeza em ambientes recifais, formigas defensoras de plantas, mimetismo mülleriano e bactérias fixadoras de nitrogênio em raízes de plantas. As interações mutualísticas estão sujeitas à trapaça por indivíduos que, por meio de algum comportamento, alcançam o benefício oferecido pelo parceiro sem oferecer nada ou oferecer muito pouco em troca. No entanto, interações mutualísticas persistem apesar da existência de trapaceiros. Neste trabalho, mostro que os parasitas de interações mutualísticas, os trapaceiros, aumentam a resiliência das redes mutualísticas às perturbações mais rapidamente em redes aninhadas, redes tipicamente encontradas em mutualismos ricos em espécies. Portanto os efeitos combinados de trapaceiros, estrutura e dinâmica das redes mutualísticas podem ter implicações para a forma como a biodiversidade é mantida. Em seguida, estudo as condições em que flores tubulares, que sofrem maiores danos ao interagirem com ladrões de néctar, conseguem coexistir com flores planares, polinizadores e pilhadores por meio de efeitos indiretos da trapaça em seu sucesso reprodutivo. O roubo do néctar pode aumentar o sucesso de uma planta se as interações com pilhadores gerarem maior quantidade de polinização cruzada, aumentando assim o sucesso reprodutivo das plantas que interagem com ambos os visitantes florais. Tal resultado sugere uma nova fonte de manutenção da cooperação e da diversidade de estratégias por meio de efeitos não lineares das interações entre diferentes estratégias. Finalmente, estudo como as interações locais promovem a prevalência de mímicos (trapaceiros) em uma certa população na ausência de seus modelos. Mostro que presas que interagem localmente podem favorecer a predominância de mímicos e predadores que os evitam após algumas gerações e que uma distribuição não aleatória de indivíduos no espaço pode reforçar ainda mais este efeito inesperado de alopatria de modelo e mímico / Mutualisms are interactions in which organisms of different species exploit each other with net benefits for both interacting individuals. Multispecific mutualistic system can be depicted as interaction networks, such as those formed by plant-pollinator interactions, dispersal systems, species interacting in cleaning stations in reef environments, protective ants in plants, müllerian mimicry, and nitrogen fixing bacteria on the roots of plants. Mutualistic interaction is subject to cheating by individuals who, by means of a diversity of behavioral strategies, achieve the benefit provided by the partner offering nothing or few in return. However, the mutualistic interactions persist despite the existence of cheaters. In this work I show that the parasites of mutualistic interactions increase the resilience of mutualistic networks to disturbances in nested networks, typically found in species-rich mutualisms. Therefore the joint effect of cheating, structure and dynamics of mutualistic networks have implications for how biodiversity is maintained. I subsequently study the conditions under which tubular flowers, which suffer stronger damages when interacting with nectar robbers, can coexist with planar flowers, pollinators, and robbers through indirect effects of cheating on their reproductive success. The theft of nectar may increase the success of a plant if its interactions with robbers generate higher degrees of cross-pollination, thus increasing the reproductive success of plants that interact with both floral visitors. This study suggests a new source of continued cooperation and diversity strategies through non-linear effects of the interactions between different strategies. Finally, I study how local interactions can promote the prevalence of mimic (the cheaters) in a given population in the absence of their models. I found that prey interacting locally may favor the predominance of mimic preys and avoid predators that, after a few generations and under a non-random distribution of individuals in space, can further strengthen this unexpected effect allopatry of the mimic and its model
86

Aproveitamento alimentar de jambolão / Food utilization of jambolan

Soares, Jackeline Cintra 10 February 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-12T15:37:10Z No. of bitstreams: 2 Dissertação - Jackeline Cintra Soares - 2015.pdf: 3919533 bytes, checksum: 35e83840358610c6b4f8b9f97390b083 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-12T15:41:50Z (GMT) No. of bitstreams: 2 Dissertação - Jackeline Cintra Soares - 2015.pdf: 3919533 bytes, checksum: 35e83840358610c6b4f8b9f97390b083 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-05-12T15:41:50Z (GMT). No. of bitstreams: 2 Dissertação - Jackeline Cintra Soares - 2015.pdf: 3919533 bytes, checksum: 35e83840358610c6b4f8b9f97390b083 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-02-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The fruits are known to be natural sources of antioxidants, among which are Vitamin C and E, carotenoids and phenolic compounds responsible for the prevention of various diseases in humans when consumed. But some fruit species are little known / exploited so little advantage. The objective of this study was to evaluate the morphology, nutritional quality, sensory and functional, technological point of view, the use of fruit jambolan in the production of pulp for the production of nectar and sherbets. The samples were collected in 5 different regions (Region 1 – North, Region 2 - South, Region 3 - Center, Region 4 – East and Region 5 - West) in Goiânia-GO, and were later processed into pulp for generation of products. For the morphological and physical analysis were selected 60 fruits (60 repetitions) of each region and conducted correlation analysis between physical and morphological properties of the fruit, after the fruits analyzes were pulped, and the pulps of each region were divided into 4 lots (4 repetitions) for physical analysis, chemical, bioactive compounds and chemical composition. The analyzes were performed on 4 replications and in triplicate. For product formulations simplex experimental design was used, varying the concentrations of water, sugar and jambolan pulp for nectar. For sherbets varied concentrations of milk, sugar and jambolan pulp. Through the physical, chemical and technical characteristics on the products could be performed to determine the influence of these ingredients in each formulation. The greatest desirability formulation was determined by the desirability test, compared with a commercial product, and using the sensory analysis of each product. Confronted the predicted results with those analyzed, the greater desirability formulation, validating the model chosen. Characterized the most desirable formulation as its chemical composition and the content of bioactive compounds. The results indicated the correlation analysis, there is a strong positive correlation above 80%, among the largest diameter (D1), smaller diameter (D2), length (H1) and fruit volume (VF) with the fruit mass (MF). The color of jambolan pulps are related to the degree of fruit ripening by changing the content of anthocyanins, and the pulp of fruits jambolan and highlighted as a source of anthocyanins and vitamin C. jambolan pulp showed high humidity and low in lipids. Sherbets showed non-Newtonian and pseudoplastic behavior, and the model that best fit was the Herschel-Bulkley model. The influence of ingredients in the formulations of sherbets indicated that high levels of sugar are related to increased melt rate, elasticity, cohesiveness and brightness. The consumption of sherbets jambolan can be recommended due to the nutritional value and the presence of phenolic compound (96.86mg eq. AG mg-1). AT, SST, SST / AT, color and VA changed according to variations in ingredients in nectars formulations. The nectar jambolan showed high content of phenolic compounds (104.70mg Eq. AG g-1) and high antioxidant capacity and may offer health benefits. / Os frutos são conhecidas por serem fontes naturais de antioxidantes, dentre os quais estão à vitamina C e E, carotenóides e compostos fenólicos, responsáveis pela prevenção de várias doenças no homem quando consumidas. Porém algumas espécies frutíferas são pouco conhecidas/exploradas, portanto pouco aproveitadas. O objetivo deste trabalho foi avaliar a morfologia, a qualidade nutricional, sensorial e funcional, do ponto de vista tecnológico, da utilização de frutos de jambolão, na produção de polpa para produção de néctares e sherbets. As amostras foram coletadas em 5 diferentes regiões (Região 1 - Norte, Região 2 - Sul, Região 3 - Centro, Região 4 – Leste e Região 5 – Oeste) na cidade de Goiânia-GO, e posteriormente foram processados em polpa para geração dos produtos. Para as análises morfológicas e físicas foram selecionados 60 frutos (60 repetições) de cada região e realizou análise de correlação entre as propriedades físicas e morfológicas dos frutos, após as análises os frutos foram despolpados, e as polpas de cada região foram divididas em 4 lotes (4 repetições) para realização das análises físicas, químicas, compostos bioativos e composição centesimal. As análises foram realizadas em 4 repetições e em triplicata. Para as formulações dos produtos foi utilizado o delineamento Simplex, variando as concentrações de água, açúcar e polpa de jambolão para os néctares. Para os sherbets variaram as concentrações de leite, açúcar e polpa de jambolão. Através das características físicas, químicas e tecnológicas realizada nos produtos foi possível determinar a influência destes ingredientes em cada formulação. A formulação de maior desejabilidade foi determinada através do teste de desejabilidade, comparando com um produto comercial, e utilizando a análise sensorial de cada produto. Confrontaram-se os resultados preditos com os analisados, da formulação de maior desejabilidade, validando o modelo escolhido. Caracterizou-se a formulação mais desejável quanto a sua composição centesimal e o teor de compostos bioativos. Os resultados indicaram na análise de correlação, existe uma forte correlação positiva, acima de 80%, entre o diâmetro maior (D1), diâmetro menor (D2), comprimento (H1) e volume do fruto (VF) com a massa do fruto (MF). A cor das polpas de jambolão estão relacionadas com o grau de maturação dos frutos, alterando o conteúdo de antocianinas, sendo a polpa dos frutos de jambolão e destacaram como fonte de antocianinas e vitamina C. A polpa de jambolão apresentou alta umidade e baixo teor de lipídeos. Os sherbets apresentaram comportamento não newtoniano e pseudoplástico, e o modelo que melhor ajustou foi o modelo Herschel-Bulkley. A influência dos ingredientes nas formulações dos sherbets indicaram que altos teores de açúcar estão relacionados com maior taxa de derretimento, elasticidade, coesividade e luminosidade. O consumo de sherbets de jambolão pode ser recomendado devido aos aspectos nutritivos e a presença de compostos fenólicos (96,86mg Eq. AG mg-1). A AT, SST, SST/AT, cor e VA alteraram de acordo com as variações dos ingredientes nas formulações de néctares. O néctar de jambolão apresentou alto teor de compostos fenólicos (104,70mg Eq. AG g-1) e alta capacidade antioxidante, podendo oferecer benefícios a saúde.
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Transporte de pólen de espécies ornitófilas e energia disponível para beija-flores em área de Mata Atlântica, Núcleo Picinguaba/PESM, Ubatuba, SP / Pollen transport of p ornithophilous species and available energy for hummingbirds in an Atlantic Forest area, Núcleo Picinguaba/ PESM, Ubatuba, SP

Fonseca, Lorena Coutinho Nery da, 1981- 20 August 2018 (has links)
Orientador: Marlies Sazima / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T00:54:41Z (GMT). No. of bitstreams: 1 Fonseca_LorenaCoutinhoNeryda_D.pdf: 15688849 bytes, checksum: 5ab648e9c0a851952dff287bd487d46e (MD5) Previous issue date: 2012 / Resumo: O estudo das relações entre beija-flores e plantas, do fluxo polínico entre as espécies polinizadas e da área utilizada por estas aves é importante para melhor entendimento dos processos evolutivos que levaram a estas interações, além de fornecer subsídios para a conservação das espécies envolvidas. O presente estudo fornece informações sobre a distribuição temporal do recurso alimentar (néctar), a disponibilidade de energia no néctar e o transporte de pólen de espécies polinizadas por beija-flores em área de Mata Atlântica. O estudo foi realizado no Parque Estadual da Serra do Mar, sudeste do Brasil, em área de Mata Atlântica de terras baixas. Os beija-flores foram capturados mensalmente com redes de neblina, anilhados e os grãos de pólen foram retirados com fita adesiva para análise em laboratório. Para verificar a distribuição do recurso alimentar ao longo do ano, foi registrada a fenologia floral das espécies ornitófilas de uma área com 5000m2. O volume e a concentração de açúcares do néctar das espécies foram medidos para o cálculo da quantidade de calorias disponíveis na área. Foram coletados estigmas de duas espécies de plantas (Canistropsis seidelii e Psychotria nuda) para verificar se há transporte de pólen interespecífico mediado por beija-flores. Foram capturadas seis espécies de beija-flores: Amazilia fimbriata, Florisuga fusca, Phaethornis ruber, Phaethornis squalidus, Ramphodon naevius e Thalurania glaucopis. Ramphodon naevius foi a espécie mais abundante e os dados de recaptura demonstraram que esta espécie permanece na área ao longo do ano. Foram registradas oito famílias com espécies ornitófilas: Bromeliaceae com 15 espécies, Gesneriaceae com três espécies, Rubiaceae com duas espécies e Acanthaceae, Fabaceae, Heliconiaceae, Loranthaceae e Orchidaceae com uma espécie cada. A disponibilidade de recursos variou ao longo do ano, o que influencia as áreas de forrageamento dos beija-flores. Segundo as estimativas realizadas, um beija-flor precisaria ao menos entre 0,37 ha e 4,7 ha para obter recurso (néctar) suficiente na área de estudo. Foram encontrados 31 morfotipos polínicos nos beija-flores, sendo Bromeliaceae a família que apresentou maior quantidade de morfotipos. As amostras apresentavam entre um e seis morfotipos de pólen e a maioria apresentou dois ou mais. Foram encontrados 29 morfotipos polínicos em Ramphodon naevius, cinco em Thalurania glaucopis e quatro em Florisuga fusca. Nos indivíduos de Ramphodon naevius que apresentaram sobreposição de grãos interespecíficos, houve predominância de um morfotipo por local de deposição. Houve deposição de grãos interespecíficos de pólen nos estigmas das duas espécies de plantas, porém o número de grãos interespecíficos foi baixo. Apesar de Ramphodon naevius transportar com freqüência grãos de pólen entre as espécies de plantas, na maior parte das vezes os grãos transportados em determinado local da cabeça pertencem, em sua maioria, a apenas uma espécie. O transporte de pólen entre espécies é baixo, embora seja frequente. É sugerido que este transporte interfira pouco no sucesso reprodutivo das plantas que participam desta interação / Abstract: Studies about bird and plant interaction, pollen transfer between bird-pollinated plants and the area used by hummingbirds are needed to improve our knowledge about the processes involved in bird-plant interactions and about their conservation. In this study, we provide information about temporal distribution of food resources (nectar), energy availability on nectar and pollen transfer between hummingbird-pollinated species in a lowland Atlantic Forest area. The study was conducted at Parque Estadual da Serra do Mar, southeastern Brazil. Hummingbirds were captured monthly and received metallic bands. Pollen grains were collected from hummingbirds'bill and head with transparent tapes and then placed on a glass microscope slide for latter analyses. Records on the floral phenology of the ornithophilous species were made monthly in a 5000 m2 area. The quantity of calories in the nectar was estimated from the values of volume and sugar concentration. We collected stigmas from two species (Canistropsis seidelii and Psychotria nuda) in order to quantify the pollen transfer between the species. We captured six hummingbird species: Amazilia fimbriata, Florisuga fusca, Phaethornis ruber, Phaethornis squalidus, Ramphodon naevius and Thalurania glaucopis. Ramphodon naevius was the most abundant species and the data about recaptures through the year indicate that it is a resident species. We registered ornithophilous species from eight families: Bromeliaceae (15 species), Gesneriaceae (3 species), Rubiaceae (2 species) and Acanthaceae, Fabaceae, Heliconiaceae, Loranthaceae and Orchidaceae (one species each). The food resource availability varied through the year, influencing the size of the area used by hummingbirds. According to the estimations, a hummingbird would need an area of, at least, 0,37 ha to 4,7 ha to obtain enough resources. Hummingbirds carried 31 morphospecies of pollen grains and Bromeliaceae had many morphospecies. Each hummingbird carried from one to six morphospecies of pollen grains and most of them carried two or more of them. There were 29 morphospecies in Ramphodon naevius, five in Thalurania glaucopis and four in Florisuga fusca. Individuals of Ramphodon naevius that carried two or more morphospecies at the same place of its body had one morphospecies more abundant than the others. There was deposition of interespecific pollen grains on the stigmas of the studied species, but the number of interespeficif pollen grains was low. Despite transporting often pollen grains between species, Ramphodon naevius transported mainly one morphospecies on each part of its head or bill. The pollen transfer between species was low, although it was frequent. We suggest that the interespecific pollen transfer between these hummingbird-pollinated species may have little effect on its reproductive assurance / Doutorado / Biologia Vegetal / Doutor em Biologia Vegetal
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Néctar de pitanga preparado com diferentes edulcorantes : determinação do perfil sensorial e estudos com consumidores / Pitanga nectar prepared with different sweeteners : sensory profile determination and consumer studies

Freitas, Mírian Luisa Faria, 1987- 21 August 2018 (has links)
Orientador: Helena Maria André Bolini / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-21T19:49:42Z (GMT). No. of bitstreams: 1 Freitas_MirianLuisaFaria_M.pdf: 2081844 bytes, checksum: 908876182e20501c6c2b0124bf9a5e26 (MD5) Previous issue date: 2013 / Resumo: Os objetivos deste estudo foram: elaborar a formulação do néctar de pitanga, verificar a quantidade necessária de cada edulcorante para substituir a sacarose e traçar o perfil sensorial e o comportamento do consumidor diante desse produto, utilizando métodos sensoriais. Na caracterização físico-química da polpa de pitanga obteve-se 6,45 °Brix para sólidos solúveis; 3,12 para pH; 1,19 % de ácido cítrico para acidez total titulável; 11,187 mg de ácido ascórbico para 100 g de polpa; e, com relação à cor, 40,39 para L*, 19,84 para a* e 19,54 para b*. Quanto à caracterização microbiológica, os resultados mostraram ausência de Salmonella, coliformes totais, coliformes termotolerantes e Alicyclobacillus. A quantidade de polpa considerada ideal pelo teste de determinação da diluição ideal foi de 25 %, enquanto que a quantidade de sacarose considerada ideal pelo teste de determinação da doçura ideal foi de 10 %. A concentração equivalente de cada edulcorante para substituir a sacarose no néctar de pitanga foi: 0,0160 % de sucralose; 0,0541 % de aspartame; 0,1000 % de estévia com 40 % de rebaudiosídeo A; 0,0999 % de estévia com 95 % de rebaudiosídeo A; 0,0017 % de neotame e 0,0360 % de ciclamato/sacarina 2:1. A análise descritiva quantitativa descreveu as amostras de néctar de pitanga utilizando 21 termos descritores, sendo: Aparência - cor laranja, presença de espuma, presença de partículas, viscosidade aparente e brilho. Aroma - aroma de pitanga, aroma doce, aroma de folha de pitanga e aroma cítrico. Sabor - sabor de pitanga, doçura, amargor, sabor residual doce, sabor residual amargo, adstringência, acidez, sabor de folha de pitanga e sabor metálico. Textura - viscosidade, corpo e presença de partículas. Pelas curvas tempo-intensidade para o estímulo doce, as amostras de néctar de pitanga que apresentaram maior intensidade e duração desse estímulo foram preparadas com neotame e estévias, evidenciando que esses possuem sabor residual doce. Quando preparadas com sacarose, sucralose, aspartame e ciclamato/sacarina 2:1 apresentaram menor intensidade e duração do estímulo doce, sendo entendidas como não tendo sabor residual doce. Quanto ao tempo-intensidade para o estímulo amargo, as amostras preparadas com estévias se destacaram quanto à intensidade e duração desse estímulo, caracterizando, além do gosto amargo, também o residual amargo. As amostras preparadas com sucralose, aspartame e sacarose possuem tanto intensidade quanto duração do estímulo um pouco menor, deixando a entender que essas amostras possuem o gosto amargo característico da pitanga, e não apresentam sabor residual amargo. De acordo com os resultados da análise de aceitação pelos consumidores, as amostras preparadas com sucralose, aspartame e neotame apresentaram aceitação similar da amostra preparada com sacarose, sendo as mais aceitas. Em todos os testes sensoriais realizados neste trabalho, a amostra de néctar de pitanga preparada com sucralose foi a que mais se aproximou da amostra preparada com sacarose. Portanto, a substituição da sacarose por sucralose seria bem sucedida em néctar de pitanga. As amostras preparadas com aspartame e ciclamato/sacarina 2:1 também se aproximaram da amostra preparada com sacarose em alguns testes / Abstract: The objectives of this study were: to develop a pitanga nectar formulation, to verify the necessary amount of each sweetener to replace sucrose and to analyze the sensory profiling and consumer behavior. The pitanga pulp had its physical-chemical properties characterized. They were 6.45 °Brix for soluble solids, 3.12 for pH, 1.19 % of citric acid for titratable acidity, 11.187 mg of ascorbic acid per 100 g of pulp, and about color: 40.39 for L*, 19.84 for a* and 19.54 for b*. The results were negative for Salmonella, coliform bacteria, thermotolerant coliform and Alicyclobacillus on microbiological characterization. The ideal dilution test resulted in 25 % pulp, and the ideal sweetness test, in 10 % sucrose. Sweeteners concentrations to replace sucrose were: 0.0160 % sucralose, 0.0541 % aspartame, 0.1000 % stevia 40 % rebaudioside A, 0.0999 % stevia 95 % rebaudioside A, 0.0017 % neotame and 0.0360 % cyclamate/saccharin blend 2:1. The quantitative descriptive analysis assessors elaborated 21 terms to describe the pitanga nectar samples. They were as follows: Appearance - orange color, foam presence, particles presence, apparent viscosity and brightness. Aroma - pitanga aroma, sweet aroma, pitanga leaf aroma and citrus aroma. Flavor - pitanga flavor, sweetness, bitterness, sweet aftertaste, bitter aftertaste, astringency, acidity, pitanga leaf flavor and metalic flavor. Texture - viscosity, body and particles presence. In the sweet taste Time-Intensity curves pitanga nectar samples with higher intensity and duration were prepared with neotame and the 2 kinds of stevia, this show that they have sweet aftertaste. The samples prepared with sucrose, sucralose, aspartame and cyclamate/saccharin blend 2:1 had less intensity and duration of sweet taste, so sweet aftertaste was not perceived. In the bitter taste time-intensity curves pitanga nectar samples prepared with the 2 kinds of stevia showed the highest intensity and duration. They have both bitter taste and bitter aftertaste. On the other hand, the samples prepared with sucrose, aspartame and sucralose have smaller intensity and duration of bitter taste. These samples have the characteristic pitanga bitter taste and no bitter aftertaste. According to the acceptance analysis results the samples prepared with sucralose, aspartame and neotame were similar to the sucrose sample and were the most accepted. In all sensory tests conducted in this study, the pitanga nectar sample prepared with sucralose was closer to the sucrose sample. Therefore, replacement of sucrose with sucralose would be successful in pitanga nectar. The samples prepared with aspartame and cyclamate/saccharin blend 2:1 were also similar to the sucrose sample in some tests / Mestrado / Consumo e Qualidade de Alimentos / Mestra em Alimentos e Nutrição
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The Ecology of Extrafloral Nectar in Senna mexicana var. chapmanii

Jones, Ian M 29 April 2016 (has links)
Extrafloral nectar (EFN) mediates food-for-protection mutualisms between plants and defensive insects. Senna mexicana var. chapmanii is a perennial legume native to the pine rockland habitats of south Florida. My dissertation focuses on how anthropogenic changes to the pine rocklands might affect EFN production by S. chapmanii, and the outcome of EFN mediated interactions. First, I investigated the influence of time of day, leaf damage, and leaf age on EFN production in S. chapmanii. Plants produced more nectar at night than during the day, and leaf damage resulted in increased EFN production. Furthermore, the response to leaf damage was greater when plants were damaged in the morning than when plants were damaged at night. Damage to young leaves elicited a stronger defensive response than damage to older leaves, in line with optimal defense theory. Second, I conducted a field experiment to determine the effects of ant activity, and light intensity, on herbivory rates, growth, and reproductive fitness in S. chapmanii. In shaded habitats, the presence of ants had no effect on herbivory rates, seed set, or plant size. In sunny habitats, however, plants with ants suffered less herbivore damage, produced more seeds, and grew larger over the duration of the one year study. Third, through a controlled greenhouse experiment I examined the effects of light intensity, and red/far-red light ratios, on EFN production in S. chapmanii. Plants in light-limited conditions produced less EFN, and leaf damage elicited increased EFN production regardless of light conditions. Ratios of red/far-red light, however, did not affect EFN production in either damaged or undamaged plants. Finally, I conducted a field study to determine how ants affect reproductive fitness in S. chapmanii. Over a period of eight months I observed the effects of ants on the activity of herbivores, predators, pollinators, and pre-dispersal seed predators. Relative pollinator efficiency, and rates of pre-dispersal seed predation, were unaffected by ants. Plants with ants, however, were quicker to establish, grew larger, and produced floral displays that attracted more pollinators. In S. chapmanii ants affected plant reproductive fitness simply by facilitating growth and establishment, with coincidental effects on reproductive investment.
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Alien tree's sugary S.O.S. exploited by thieving tramp ant: unidirectional benefit in an alien, tritrophic mélange

Jones, Emily Elizabeth 26 September 2019 (has links)
No description available.

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