Teses / dissertações sobre o tema "Plant gas exchange"

Pinus brutia var. eldarica is often considered to possess photosynthetic characteristics that make it highly tolerant to drought conditions. However, very little is known about it's photosynthetic response to water stress under either laboratory or field imposed drought conditions. The purpose of this study was to utilize laboratory gas-exchange measurements to determine the effects of water stress and recovery from stress on photosynthetic capacity of potted Pinus brutia via. eldarica plants. Analysis of the rate assimilation (A) versus intercellular CO₂ (Cᵢ) data indicates that recovery of carboxylation efficiency (g'm) (i.e. Rubisco activity and amount) does occur after daily re-watering of moderately stressed (ψ₂ ≃ -2.0 MPa) Pinus brutia. However, these same data indicate that irreversible damage to cell membranes results in an inability to re-generate RubP. Although inferences on the effect of stress on A in field grown Pinus brutia is tenuous, these laboratory results indicate that Pinus brutia may not be as drought tolerant as commonly believed.

The working hypothesis for this dissertation was that the contrasting plant architecture, and the distinct native environments of Hesperaloe funifera and H. nocturna should be reflected in differences in their eco-physiological responses, and that these, in turn, would determine these species' adaptability limits and productivity under cultivation. The objective of this dissertation project was to evaluate plant morphological characteristics and their effect on physiological processes, and how environmental factors interact with these processes in H. funifera and H. nocturna. Common to both Hesperaloe funifera and H. nocturna is the possession of constitutive crassulacean acid metabolism (CAM). The major implication of CAM is a prominent water use efficiency (WUE). Although instantaneous net CO₂ uptake rates of both Hesperaloe funifera and H. nocturna are low when compared with C₃ plants, integrated 24-hr net CO₂ uptake rates are within the lower range of C₃ species. Because there is a relatively large range of conditions in which photosynthesis occurs (i.e., both Hesperaloe species have a long growing season), net CO₂ uptake in Hesperaloe integrated throughout the year may reach or surpass that of C₃ crops. Daily integrated CO₂ uptake during late fall, winter and early spring were similar in Hesperaloe funifera and H. nocturna. A major peak in CO₂ uptake was found during the fall for H. funifera but not for H. nocturna. Also, no reduction in integrated CO₂ uptake was found in H. nocturna during the summer months, while H. funifera showed a considerable reduction in CO₂ uptake during this season. The increase in photosynthetic activity in H. nocturna coincided with the emergence of the inflorescence. Contrastingly, flowering did not appear to increase net CO₂ uptake in H. funifera. In this species a flush of new leaf production (increased sink demand) coincides with the observed increase in photosynthesis during the fall. The late fall peak of CO₂ uptake found in H. funifera could also be caused by a photoperiodic stimulation of CO₂ uptake. Significant differences in WUE between the two Hesperaloe species were found. These differences were, at least, partially explained by contrasting plant architecture and differences in leaf morphology.

This project aims at investigating the effect of CO2 enrichment on the growth and gas exchange of C3, C3-C4 and C4 Panicum grasses. Potted plants were grown in soil under well watered conditions, in artificially lit environmentally controlled cabinets or naturally lit greenhouses at varying levels of CO2 enrichment. CO2 enrichment enhanced the dry weight of C3 and C4 Panicum species under optimal light and N supplies, but had no effect on the total leaf N or TNC concentrations. The high-CO2 induced photosynthetic reaction in the C3 species was accompanied by a reduced Rubisco concentration and was related to the conservation of the relative growth rate of the plant. Elevated CO2 had no effect on the photosynthetic capacity of the C4 species, but enhanced its CO2 assimilation rates under high light and N supplies. The effect of elevated CO2 on the leaf and stem anatomy reflected increased carbon supply at high CO2 in the C3 grass, and reduced transpiratory demand at high CO2 in C4 grasses. Consequently, it is clear that both C3 and C4 grasses are likely to be more productive under rising atmospheric CO2 concentrations.<br>Doctor of Philosophy (PhD)

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico<br>Boron, among micronutrients, is one that appears most often deficient in the soil, mainly due to the low availability of land and lack of knowledge of application and crop response to their application. As to the low availability in the soil, this condition is aggravated when the water shortage, since the mechanism involved in the contact with the root of boron is the mass flow that is directly proportional to the hydraulic conductivity. Regarding response to nutrient culture, it is believed that the optimal range between toxic and is very narrow. Therefore the objective of this study was to evaluate the effect of increasing doses of boron in watermelon crop irrigated with different irrigation in the municipality of Pentecost - CE. The statistical design was randomized block split plot with four replications. The plots were assessed four irrigation levels, 50%, 75%, 100% and 125% of potential evapotranspiration of the crop (ETpc) and subplots five levels, corresponding to 0.5, 1.5, 2.5, 3, 5, 4.5 kg ha-1 to B, taking with boric acid source. The boron contents in watermelon leaf tissue showed linear fit as a function of increasing doses and decreased linearly as a function of irrigation levels, ranging from 102.39 to 168.20 mg kg-1 and negatively correlated with productivity, indicating toxicity. Foliar N, P, K, Ca, Mg, Mn, Fe and Zn were not affected by irrigation and boron levels. Since sulfur and copper, influenced by irrigation and B levels, respectively. It was demonstrated effect of boron on the increased production of MSPA. The stomatal conductance, internal CO2 concentration and photosynthesis were not affected by factors, demonstrating that the blades did not impose on plants water scarcity, and that with the variables analyzed was impossible to pinpoint the influence of boron gas exchange. The crop transpiration was significantly affected by irrigation.<br>O boro, dentre os micronutrientes, à aquele que mais frequentemente se apresenta deficiente no solo, devido principalmente à baixa disponibilidade dos solos e a falta de conhecimento do requerimento e da resposta das culturas a sua aplicaÃÃo. Quanto à baixa disponibilidade no solo, tal condiÃÃo seria agravada, quando da escassez hÃdrica, uma vez que o mecanismo envolvido no contato do boro com a raiz à o fluxo de massa, que à diretamente proporcional à condutividade hidrÃulica do solo. A respeito da resposta da cultura ao nutriente, acredita-se que a faixa entre o nÃvel ideal e o tÃxico seja muito estreita. Sendo assim o objetivo deste trabalho foi avaliar o efeito da aplicaÃÃo de doses crescentes de boro na cultura da melancia irrigada com diferentes lÃminas de irrigaÃÃo, no municÃpio de Pentecoste â CE. O delineamento estatÃstico foi blocos casualizados com parcelas subdivididas e quatro repetiÃÃes. Nas parcelas foram avaliados quatro lÃminas de irrigaÃÃo, 50%, 75%, 100% e 125% da evapotranspiraÃÃo potencial da cultura (ETpc) e nas subparcelas cinco doses, correspondentes a 0,5, 1,5, 2,5, 3,5, 4,5 kg ha-1 de B, tendo com fonte o Ãcido bÃrico. Os teores de boro no tecido foliar da melancia apresentaram ajuste linear crescente em funÃÃo das doses e linear decrescente em funÃÃo das lÃminas de irrigaÃÃo, variando de 102,39 a 168,20 mg kg-1 e correlacionando negativamente com a produtividade, indicando toxidez. Os teores foliares de N, P, K, Ca, Mg, Mn, Fe e Zn, nÃo foram influenciados pelas lÃminas de irrigaÃÃo e doses de boro. Sendo o enxofre e o cobre, influenciados pelas lÃminas de irrigaÃÃo e doses de B, respectivamente. Foi demostrado efeito do boro sobre o incremento da produÃÃo de MSPA. A condutÃncia estomÃtica, concentraÃÃo interna de CO2 e a fotossÃntese nÃo foram influenciadas pelos fatores, demostrando que as lÃminas nÃo impuseram sobre as plantas uma escassez hÃdrica, e que com as variÃveis analisadas foi impossÃvel precisar a influencia do boro nas trocas gasosas. A transpiraÃÃo da cultura foi influenciada significativamente pelas lÃminas de irrigaÃÃo

Water availability is one of the biggest constraints limiting the plant growth and species distribution around the world. This is the case in the Mediterranean region where, moreover, the frequency and amount of rainfall will decrease due to global warming. This will provoke longer periods of drought and a general decrease of water availability. In this context, one of the most vulnerable crops is grapevine. This crop has been traditionally rain-feed, although in recent years it’s becoming an irrigated crop. This increases the demand to regulate the water use by more precise irrigation techniques based on the plant water status. A good physiological indicator that allows knowing the plant water status is stomatal conductance. Although it is widely known the importance of the stoma, there is not an accurate model to predict their behavior as many physiological and environmental parameters co-regulate it. The aims of this thesis are to: a) study the physiological mechanisms regulating stomatal conductance, b) apply a process-based model to predict the behavior of stomatal conductance c) use this model as tool to better understand the physiological stomatal regulation along the canopy. Results show that stoma has a strong regulation by hydraulic conductance being a key physiological parameter regulating water use. In addition, abscisic acid and osmotic adjustment are also playing an important role in their regulation. On the other hand, the mechanistic model of stomatal conductance has been validated predicting with a good accuracy the variations throughout the day and season in well water and water stress conditions. At time, because this model is based on physiological parameters permits to infer about the relevance of those physiological parameters under water stress, predicting that hydraulic conductance has a main role on the regulation of stomatal conductance in different parts of the canopy.

This project aims at investigating the effect of CO2 enrichment on the growth and gas exchange of C3, C3-C4 and C4 Panicum grasses. Potted plants were grown in soil under well watered conditions, in artificially lit environmentally controlled cabinets or naturally lit greenhouses at varying levels of CO2 enrichment. CO2 enrichment enhanced the dry weight of C3 and C4 Panicum species under optimal light and N supplies, but had no effect on the total leaf N or TNC concentrations. The high-CO2 induced photosynthetic reaction in the C3 species was accompanied by a reduced Rubisco concentration and was related to the conservation of the relative growth rate of the plant. Elevated CO2 had no effect on the photosynthetic capacity of the C4 species, but enhanced its CO2 assimilation rates under high light and N supplies. The effect of elevated CO2 on the leaf and stem anatomy reflected increased carbon supply at high CO2 in the C3 grass, and reduced transpiratory demand at high CO2 in C4 grasses. Consequently, it is clear that both C3 and C4 grasses are likely to be more productive under rising atmospheric CO2 concentrations.

Made available in DSpace on 2014-06-11T19:32:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-22Bitstream added on 2014-06-13T20:43:35Z : No. of bitstreams: 1 cerqueira_rc_dr_botfca.pdf: 1887765 bytes, checksum: f9a04529ccfc7fde169e950ac6854a84 (MD5)<br>Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)<br>A videira por ser originária de regiões de inverno rigoroso, apresenta mecanismo de dormência que conferem condições de sobrevivência durante o período frio. Contudo, esta mesma espécie também é cultivada em condições tropicais, cuja ausência de estação com baixas temperaturas favorece seu contínuo desenvolvimento vegetativo, fazendo-se necessário estabelecer um repouso, que normalmente é promovido com a redução do fornecimento de água, através do controle da irrigação. No entanto, este processo, apesar de ter o mesmo objetivo da dormência estabelecida pelo frio, apresenta mecanismos fisiológicos e bioquímicos diferentes. Este trabalho teve o objetivo de avaliar características fisiológicas e bioquímicas de plantas de Vitis vinifera L. cv. Thompson Seedless submetidas às condições de frio e deficiência hídrica, assim como sua influência na brotação de gemas. As plantas foram conduzidas em casa-de-vegetação e submetidas aos seguintes tratamentos: 1. Controle (25-30oC / 60-70% U.R. em capacidade de campo - cc); 2. Deficiência Hídrica (25-30oC / 60-70% U.R. a uma tensão de água no solo entre -80 a -100 kPa); 3. Frio (5-13oC / 60-70% U.R. em câmara climatizada e em cc), por um período de até 90 dias, sendo cada parcela de plantas avaliada e amostrada a cada 15 dias, para em seguida ser reconduzida às condições de Controle (25-30oC/60-70%U.R em cc), onde permaneceram até a brotação. O delineamento foi inteiramente casualizado, em esquema de parcela subdividida (3 x 6); sendo a parcela representada pelos três tratamentos; enquanto a subparcela representada pelos seis tempos de permanência que as plantas foram submetidas aos tratamentos (15, 30, 45, 60, 75 e 90 dias após o tratamento – DAT). O número de repetição variou de acordo com o tipo de característica avaliada (destrutiva e não destrutiva) e cada unidade experimental foi constituída...<br>The vine is from cold winter regions and because this has dormancy mechanism conferring survival conditions during the cold period. However, these species are also cultivated in tropical conditions and absence of season with low temperatures increase vegetative growth, and because this is necessary to establish a dormant which usually is promoted with reducing water supply through irrigation control. But while used in place of cold dormancy, irrigation control has different biochemical and physiological mechanisms, this way, the aim were to evaluate physiological and biochemical characteristics of Vitis vinifera L. cv. Thompson Seedless plants submitted to cold and drought conditions, as well as its influence on bud break. Plants were growing in a green house and treated as follows: 1. Control (25-30oC / 60-70% RH at field capacity - cc), 2. Water deficiency (25-30oC/60-70% RH at a soil water tension between -80 to -100 kPa) 3. Cold (5-13oC/60-70% RH in an growth chamber acclimatized at cc), for a period up to 90 days, and plants portion were sampled and evaluated each 15 days, to then be brought back to Control conditions (25-30oC/60-70% RH in cc), where they remained until budding. The design was completely randomized in a split plot design (3 x 6) being three main treatments and sub plots constituted by six permanence time which plants were treated (15, 30, 45, 60, 75 and 90 days after treatment - DAT). The repetition number varied according characteristic evaluated (destructive and non destructive) and each plant represented one experimental unit. The following physiological characteristics were evaluated: rate of net CO2 assimilation... (Complete abstract click electronic access below)

Foram estudados os efeitos da deficiência hídrica e da aplicação de ácido abscísico (ABA) sobre alguns aspectos fisiológicos e a produção de flavonóides em plantas de calêndula. Testaramse quatro intervalos de suspensão da irrigação (controle - irrigação diária; 3; 6 e 9 dias sem irrigar) acompanhados por três doses de ABA (0, 10 e 100 µM), resultando em 12 tratamentos. O experimento foi instalado em condições de casa de vegetação com plantas envasadas. Os tratamentos foram aplicados no início do florescimento e seus efeitos foram avaliados pelo conteúdo relativo de água na folha (CRA) e trocas gasosas (A= fotossíntese líquida, gs= condutância estomática, E= transpiração, Ci= concentração intercelular de CO2 e TL= temperatura da folha); por meio de analisador portátil por infra-vermelho. A eficiência do uso da água (EUA) foi calculada como A/E. Aos 3 dias de suspensão da irrigação as plantas de calêndula não apresentaram alterações significativas nas variáveis de trocas gasosas avaliadas. Aos 6 dias de deficiência hídrica as variáveis Ci, CRA e EUA não apresentaram diferença em relação aos tratamentos com suprimento constante de água, acrescidos ou não de ABA. Porém, a imposição de estresse hídrico somada à aplicação de ABA nas plantas resultou em diminuição nos valores de E, gs, A e TL em relação aos tratamentos controle. Aos 9 dias sem irrigar ocorreram mudanças drásticas nas plantas, sendo que todos os parâmetros de trocas gasosas avaliados apresentaram reduções significativas em relação aos tratamentos controle (irrigação diária com ou sem ABA). Concluiu-se que a aplicação exógena de ABA mimetizou as respostas fotossintéticas da planta ao estresse hídrico, sendo que o efeito principal deste biorregulador foi o de causar diminuição na gs. Porém, esta redução na gs só foi acompanhada de uma redução em A quando as plantas estavam submetidas à deficiência hídrica. O efeito residual do ABA nas plantas foi de apenas 7-8 dias e portanto, as variações observadas aos 6 dias de deficiência hídrica foram provavelmente induzidas pelo ABA ; enquanto que as diferenças observadas aos 9 dias foram exclusivamente causadas pela deficiência hídrica. Não houve diferença significativa entre as diferentes intensidades de deficiência hídrica testadas com relação ao acúmulo de flavonóides nas inflorescências de calêndula. Entretanto, a aplicação de ABA provocou uma diminuição de até 50% no teor de flavonóides, tanto nas plantas controle (bem hidratadas) como nas plantas submetidas ao estresse hídrico, para todas as intensidades testadas. Concluiu-se que o ABA restringe a rota biossintética de flavonóides.<br>It was evaluated the effects of water deficit and abscisic acid (ABA) application on some physiological parameters and flavonoid production in marigold plants. It was tested four intervals of withholding water (control - diary irrigation, 3, 6 and 9 days without irrigation) accomplished of 3 concentrations of ABA (0, 10 e 100 µM), resulting in 12 treatments. The experiment was performed under nursery conditions with plotted plants. The treatments were applied in the beginning of blooming and their effects were evaluated by the relative water content (RWC) and leaf gas exchange (A= net photosynthesis, gs= stomatal conductance, E= evaporation, Ci= CO2 intercellular concentration and TL=leaf temperature); using a portable infrared gas analyzer. The water use efficiency (EUA) was calculated as A?E. At 3 days of water suppression the marigold plants did not showed significant alterations in leaf gas exchange evaluated parameters. At 6 days of water deficit the parameters Ci, RWC and EUA did not showed difference in relation to the treatments with daily irrigation, added or not of ABA. However, the water stress plus ABA application resulted in smaller values of E, gs and A in relation to control plants. At 9 days of water deficit there were drastic changes in the plants, with significant reductions in all leaf gas exchange parameters evaluated in relation to control treatments (daily irrigation with or without ABA). It was concluded that exogenous ABA application mimics the plant photosynthetic responses to water stress, and the main ABA effect was to cause a reduction on gs. However, this gs reduction only was accomplished of a reduction in A when the plants were submitted to the water deficit. The residual effect of ABA in plants was only 7-8 days and so, the differences observed at the 6 days of water deficit were probably inducted by the ABA, yet differences observed at the 9 days were exclusively caused by the water deficit. There was no significant difference among the different levels of water deficit used in relation to total flavonoids content in inflorescences of marigold. However, ABA application resulted in a reduction of almost 50% in flavonoids content, in well watered plant as well as stressed plants, for all levels of water deficit tested. It was concluded that ABA restricts the biosynthetic rote of flavonoids.

Worldwide, agriculture production continues to be constrained by a number of abiotic and biotic stresses. In areas with Mediterranean climate, drought events are expected to strengthen in terms of intensity, frequency and duration in the near future. Thus, in this area, soil water deficit is considered the main environmental factor influencing grapevine growth. At the same time, grapevines are highly subjected to different viruses from which Grapevine leafroll associated virus-3 (GLRaV-3) is one of the most widespread ones, provoking considerable economic losses in many vineyards worldwide. The identification of how different stress responses are integrated and how they affects plant growth and physiological traits, is therefore very important to ensure the continuity of vine growing. The first main objective of the present thesis was to study the sanitary status of Majorcan minority grapevines cultivars and to highlight the prevalence of GLRaV-3 in local cultivars. In this sense, the results showed that virus incidence is very high and can rise up (91.75 %) in the local grapevine cultivars conserved in the germplasm collection of the Balearic Islands. Remarkably, GLRaV-3 is the most prevalent virus in this collection (82 %). This situation urges a speedy implementation of the sanitation techniques in order to obtain virus-free certified plants. Hence, two sanitation techniques ―shoot tips culture and thermotherapy in combination with shoot tips culture‖ have been optimized for double and triple viruses‘ eradication from two local cultivars with high enological potential, Argamussa and Gorgollassa. The second main objective was to dissect the effects of virus infection, moderate water stress and its combination on main physiological processes in two local grapevine cultivars, Malvasia de Banyalbufar and Giró Ros. Each of the two studied stresses resulted in a negative effect on leaf gas-exchange parameters. Water stress in non-infected plants (WS-NI) significantly reduced plant growth and net CO2 assimilation (AN) but had only small effect on metabolic changes, indicating that AN changes were mainly constrained by diffusive parameters (stomatal (gs) and mesophyll (gm) conductance‘s). With regard to virus infection under well-watered conditions (WW-VI), the results also revealed that GLRaV-3 impaired AN through diffusional limitations rather than biochemical ones. In this case, stomatal conductance was mainly regulated by changes in hydraulic conductance at leaf level, namely leaf (Kleaf) and petiole (Kpetiole) hydraulic conductance, in which Kpetiole resulted to be the most relevant parameter to be checked when studding the effect of phloemetic viruses in plant hydraulics. Remarkably, the results of this thesis indicate that the combined stress resulted in a detrimental effect on plant growth and physiology; but any additive effect between WS and VI has been highlighted. Moreover, the combination of stresses triggers a specific response at the metabolic level, which was not quantitatively predicted by the sum of each individual stress. The observed changes in primary metabolites were closely associated with respiration metabolisms. Indeed, the specific adjustment of respiratory metabolism (i.e; cysteine, threonine, fumarate and erythronate 1,4-lactone) could potentially explain the maintenance of leaf carbon balance and growth in cultivars studies under combined stress conditions. In the present thesis, we move a step further, by revealing the importance of studding grapevine-virus infection-water stress interactions under field conditions, particularly, in white cultivars where viruses are asymptomatic and difficult to identify. Further research with differents virus concentration and high number of cultivars are needed to confirm if virus effect is concentration dependent and if there is a cultivar-susceptibility difference.<br>A escala mundial, la producción agrícola sigue estando limitada por una serie de estreses abióticos y bióticos. En las zonas de clima mediterráneo, es muy probable que, en un futuro próximo, la duración, la frecuencia y/o la intensidad de la sequía aumenten. De esta forma, en el mediterráneo, el déficit hídrico se considera el principal factor ambiental limitante del crecimiento de la vid. Al mismo tiempo, el cultivo de la vid está expuesto a diferentes enfermedades provocadas por virus, de los cuales el virus del enrollado 3 (GLRaV-3) es uno de los más extendidos, provocando importantes pérdidas económicas en muchos viñedos de grandes regiones vitícolas de todo el mundo. La identificación de cómo se integran las respuestas de diferentes estreses en la viña y también de cómo están afectando el crecimiento y la fisiología de las plantas es, por tanto, de gran interés para garantizar la continuidad del cultivo de la vid. El primer objetivo de esta tesis es estudiar el estado sanitario de las variedades minoritarios de la vid y destacar la incidencia del GLRaV-3 en las variedades locales de vid. Los resultados obtenidos han puesto de manifiesto que la incidencia de los virus es muy alta (91,75%) en las variedades locales de vid conservadas en la colección de germoplasma de las Islas Baleares. Sorprendentemente, en esta colección, GLRaV-3 es el virus que mostró una mayor incidencia (82%). En este sentido, instamos a la rápida aplicación de técnicas adecuadas de saneamiento para obtener plantas certificadas libres de virus. Por ello, se han optimizado dos técnicas de saneamiento " cultivo in vitro de ápices caulinares y la combinación de termoterapia y cultivo in vitro de ápices caulinares‖ para la erradicación de las infecciones víricas dobles y triples de dos cultivares locales de gran potencial enológico, Argamussa y Gorgollassa. El segundo objetivo principal de esta tesis es explorar los efectos del estrés hídrico, la infección vírica y la combinación de ambos sobre los principales procesos fisiológicos de dos variedades locales de vid, Malvasia de Banyalbufar y Giró Ros. Cada uno de los dos estreses estudiados resultó en un efecto negativo sobre los parámetros de intercambio gaseoso foliar. El estrés hídrico in plantas sanas (WS-NI) redujo significativamente el crecimiento de las plantas y la asimilación neta de CO2 (AN), pero solo demostró tener un efecto reducido sobre los niveles metabólicos, indicando en este caso, que los cambios de AN durante el WS se ven limitados por factores difusivos (la conductancia estomática (gs) y del mesofilo (gm)). Respecto a las plants infectadas en condiciones de riego (WW-VI) las correlaciones obtenidas entre los parámetros fisiológicos (AN, gs y gm), la concentración de virus y los metabolitos sugiere firmemente que el GLRaV-3 afecta a la AN mediante limitaciones difusivas más que bioquímicas. En este caso, la conductancia estomática fue regulada principalmente por la conductancia hidráulica a nivel foliar, concretamente conductancia hidráulica de hoja (Kleaf) y pecíolo (Kpetiole). En este trabajo, Kpetiole resultó ser el parámetro más relevante para estudiar el efecto de los virus sistémicos de tipo floemático sobre la hidráulica de la planta. Notablemente, los resultados de esta tesis indican que el estrés combinado tuvo un efecto negativo sobre el crecimiento y la fisiología de la vid; pero no se destacó ninguna interacción entre WS y VI. Por el contrario, la combinación de los dos estreses subrayó una respuesta específica a nivel metabólico, no pudiéndose predecir cuantitativamente este efecto en base a la suma de cada uno de ellos. Los cambios observados en los metabolitos primarios se asociaron estrechamente con el metabolismo respiratorio. De hecho, el ajuste específico del metabolismo respiratorio (-i.e, cisteína, treonina, fumarato y eritronato 1,4-lactona) podría explicar potencialmente el mantenimiento del balance de carbono foliar y el crecimiento de las variedades estudias bajo condiciones de estrés combinado. En la presente tesis, hemos revelado la importancia de estudiar las interacciones vid-virus-estrés hídrico en condiciones de campo, particularmente en las variedades blancas donde las infecciones son asintomáticas y difíciles de identificar. Para completar este trabajo, sería interesante realizar un experimento con diferentes concentraciones de virus en un mayor número de cultivares y así confirmar si el efecto del virus depende de la concentración y/o si hay una diferencia en la susceptibilidad entre los cultivares.<br>Actualment, la producció agrícola mundial es troba limitada per una sèrie d‘estressos abiòtics i biòtics. A les zones de clima Mediterrani, s'espera que en un futur pròxim els esdeveniments de sequera siguin encara de major importància en termes d'intensitat, freqüència i durada. Per tant, en aquestes zones, el dèficit hídric és considerat com el principal factor ambiental capaç d‘afectar el creixement de la vinya. A més, la vinya es troba altament sotmesa a diferents virus, entre els quals, Grapevine leafroll-associated virus-3 (GLRaV-3) és un dels més estesos, provocant pèrdues econòmiques considerables a moltes vinyes d‘arreu del món. La identificació de com les diferents respostes a l‘estrès es troben integrades a la vinya i de com aquestes afecten el creixement i la fisiologia de les plantes és, per tant, de gran interès per a garantir la continuïtat del cultiu de la vinya. El primer objectiu d‘aquesta tesi tracta d‘estudiar l'estat sanitari dels cultivars minoritaris de vinya a Mallorca i destacar la prevalença a la vinya del virus GLRaV-3. Aquest estudi demostra una incidència d'infeccions víriques simples i múltiples (91,75%) molt alta en els cultivars locals de vinya, actualment conservats a la col·lecció de germoplasma de les Illes Balears. Sorprenentment, GLRaV-3 és el virus que més predomina en aquesta col·lecció (82%). Aquest resultat impulsa la necessitat d'una aplicació dràstica de tècniques de sanejament per tal d'obtenir plantes certificades lliures de virus. En aquest treball, s'han optimitzat dues tècniques de sanejament ―shoot tips culture and thermotherapy in combination with shoot tips culture‖ per a l'eradicació de virus dobles i triples a dos cultivars locals amb alt potencial enològic, Argamussa i Gorgollassa. El segon objectiu principal d‘aquesta tesi és estudiar els efectes de la infecció vírica, l'estrès hídric moderat i la seva combinació sobre els principals paràmetres fisiològics a dues varietats locals de vinya, Malvasia de Banyalbufar i Giró Ros. Cada un dels estressos estudiats, va resultar en un efecte negatiu sobre l'intercanvi de gasos a nivell foliar. L'estrès hídric a plantes sanes (WS-NI) va reduir de manera significativa el creixement de les plantes i l'assimilació neta al CO2 (AN), en canvi, sols va afectar lleugerament els canvis metabòlics, el que indicà que canvis sobre la AN durant l‘estrès hídric foren principalment deguts a les limitacions sofertes sobre determinats paràmetres difusius, com son la conductància estomàtica (gs) i la conductància del mesòfil (gm). A les plantes infectades per virus i cultivades sota condicions de reg (WW-VI), s‘obtingueren correlacions significatives entre els paràmetres fisiològics (AN, gs i gm), la concentració de virus i la presència de metabòlits. Aquestes correlacions varen desvelar que la presència de GLRaV-3 afectà la AN a través de limitacions difusives i no bioquímiques. En aquest cas, la conductància estomàtica es regí principalment pels canvis en la conductància hidràulica a nivell de la fulla (Kleaf) i el pecíol (Kpetiole), essent Kpetiole el paràmetre més rellevant alhora d‘estudiar l'efecte de virus floemàtics sobre el sistema hidràulic de la planta. Cal remarcar que els resultats obtinguts en aquest treball indiquen que la presència d‘un estrès combinat tingué un efecte negatiu sobre el creixement i la fisiologia de la vinya; però en cap cas es destacà una interacció entre WS i VI. Per contra, la combinació d‘ambdós estressos desencadenà una resposta específica a nivell metabòlic, que no va ser quantitativament predita per la suma dels dos. Els canvis observats en els metabòlits primaris varen resultar estar estretament associats amb el metabolisme respiratori. De fet, l'ajust específic del metabolisme respiratori (és a dir, cisteïna, treonina, fumarat i eritronat 1,4-lactona) podria explicar el manteniment de l'equilibri entre el balanç de carboni i el creixement en els dos cultivars estudiats. En el present treball, s‘ha avançat en quant a revelar quant d‘important és l‘estudi de les interaccions virus-estrès hídric a la vinya en condicions de camp, en particular, en els cultivars de raïm blancs on els efectes del virus són asimptomàtics i més difícils d'identificar. En un futur, es necessitaria aprofundir en aquest camp mitjançant la realització d‘estudis addicionals amb diferents concentracions víriques i un major nombre de cultivars per a ser capaços de confirmar si l'efecte del virus sobre la vinya depèn de la seva concentració i si cada cultivar presenta diferent susceptibilitat a la presència del virus.

RIBEIRO, Maria da Saúde de Sousa. Ecofisiologia e produtividade de alecrim pimenta nas condições edafoclimáticas do Maciço de Baturité, Ceará. 2015. 89 f. Dissertação (Mestrado em Engenharia Agrícola)-Universidade federal do Ceará, Fortaleza, 2015.<br>Submitted by Vitor Campos (vitband@gmail.com) on 2016-10-14T22:37:54Z No. of bitstreams: 1 2015_dis_mssribeiro.pdf: 1517482 bytes, checksum: 56118c5543f3344952bc71199520b88d (MD5)<br>Approved for entry into archive by Jairo Viana (jairo@ufc.br) on 2016-10-18T18:48:55Z (GMT) No. of bitstreams: 1 2015_dis_mssribeiro.pdf: 1517482 bytes, checksum: 56118c5543f3344952bc71199520b88d (MD5)<br>Made available in DSpace on 2016-10-18T18:48:55Z (GMT). No. of bitstreams: 1 2015_dis_mssribeiro.pdf: 1517482 bytes, checksum: 56118c5543f3344952bc71199520b88d (MD5) Previous issue date: 2015<br>The medicinal plants are included within the wide diversity of the Maciço de Baturité ecosytem and they are an important component of traditional medicine of this region. However, scientific information that may contribute to the increase in the cultivation of these plants are still rare, particularly at conditions of the State of Ceará. The overall objective of this project is to evaluate the development and the production of alecrim pimenta (Lippia origanoides) at conditions of Maciço de Baturité, Ceará. Two experiments were conducted, the first during the dry season of 2013 (August to November) and the second during the rainy season of 2014 (February to May). The experiment was corned out in completely randomized design with split plots, being the plots defined by two seasons (drought and rainy), the subplot formed by light conditions (greenhouse and full sun), and the subsubplots formed by four evaluation times (0, 40, 80 and 120 days after transplanting). Five replications were used, each one represented by a pot of 20 L containing a plant. The following variables were evaluated: leaf area, plant height, stem diameter, dry matter production, leaf gas exchange, chlorophyll content, mineral nutrients, organic solutes, and essential oils. The alecrim pimenta grows well in the Baturité region, with yields of biomass and essential oil similar to those observed in other studies. The cultivation in greenhouse (50% of solar radiation) changed the pattern of development of alecrim pimenta, resulting in plants with better overall appearance, taller, with larger leaves, higher specific leaf area, less developed root system, and lower root/shoot ratio, regardless of the season of cultivation. The production of dry biomass of leaves and total did not differ between the two environments (light conditions) after 120 days cultivation, regardless of the period of year. During the drought season there was a strong influence of the light condition on stomatal conductance and transpiration, with the values being lower in full sun environment, suggesting stomatal sensitivity to climate conditions in this species. Plants grown in greenhouse showed, in general, higher levels of nutrients and nitrogen compounds (N-aminossolúveis), compared to plants under full sunlight, regardless of the cropping season.<br>Dentre os vegetais que compõem ampla diversidade do Maciço de Baturité se inserem as plantas medicinais, sendo estas, principais componentes da medicina tradicional. No entanto, informações científicas que possam contribuir para o incremento do cultivo dessas plantas ainda são raras, particularmente nas condições edafoclimáticas do Estado do Ceará. Objetivou-se com o presente trabalho, avaliar o desenvolvimento e o potencial produtivo do alecrim pimenta (Lippia origanoides) nas condições edafoclimáticas do Maciço de Baturité, Ceará. Foram realizados dois experimentos, sendo o primeiro durante o período seco de 2013 (agosto a novembro) e o segundo durante o período chuvoso de 2014 (fevereiro a maio). O experimento foi conduzido seguindo um delineamento inteiramente casualizados com parcelas subsubdivididas, sendo as parcelas definidas pelas duas estações (seca e chuvosa), as subparcelas formadas pelas condições de luminosidade (telado e pleno sol), e as subsubparcelas pelas quatro épocas de avaliação (0, 40, 80 e 120 dias após o transplantio). Foram utilizadas cinco repetições, sendo cada repetição representada por um vaso de 20 litros contendo uma planta. Foram avaliadas as seguintes variáveis: área foliar, altura da planta, diâmetro do caule, massa seca dos diferentes órgãos vegetais, trocas gasosas, teores de clorofila, teores de minerais, solutos orgânicos e rendimento do óleo essencial. O alecrim pimenta desenvolveu-se bem na região do Maciço de Baturité, com produtividades de biomassa e de óleo essencial similares às observadas em outros estudos. O cultivo em telado alterou o padrão de desenvolvimento do alecrim pimenta, resultando em plantas com melhor aparência geral, mais altas, com folhas maiores, maior área foliar específica, menor desenvolvimento do sistema radicular e menor relação raiz/parte aérea, independentemente da época de cultivo. A produção de massa seca de folhas e total não diferiu entre os dois ambientes após 120 dias de cultivo, independentemente do período do ano. Houve forte influência do ambiente de cultivo no período seco, sobre a condutância estomática e a transpiração, com os valores sendo menores no ambiente a pleno sol, sugerindo a sensibilidade estomática da espécie às condições atmosféricas do período. As plantas cultivadas em telado apresentaram, de forma geral, maiores teores de nutrientes minerais e de compostos nitrogenados (N-aminossolúveis), em comparação às plantas submetidas a pleno sol, independente do época de cultivo.

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-03-19T18:37:15Z No. of bitstreams: 1 viníciussacramentopacheco.pdf: 1524403 bytes, checksum: da3bc47331a9b9d21aceffe2209ed60f (MD5)<br>Rejected by Adriana Oliveira (adriana.oliveira@ufjf.edu.br), reason: Nome do autor não pode ser salvo com acento on 2018-03-19T19:36:45Z (GMT)<br>Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-03-19T19:41:33Z No. of bitstreams: 1 viníciussacramentopacheco.pdf: 1524403 bytes, checksum: da3bc47331a9b9d21aceffe2209ed60f (MD5)<br>Rejected by Adriana Oliveira (adriana.oliveira@ufjf.edu.br), reason: Nome do autor tem que ser salvo sem acento on 2018-03-19T19:42:52Z (GMT)<br>Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-03-19T20:19:33Z No. of bitstreams: 1 viniciussacramentopacheco.pdf: 1524403 bytes, checksum: da3bc47331a9b9d21aceffe2209ed60f (MD5)<br>Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-03-21T13:00:16Z (GMT) No. of bitstreams: 1 viniciussacramentopacheco.pdf: 1524403 bytes, checksum: da3bc47331a9b9d21aceffe2209ed60f (MD5)<br>Made available in DSpace on 2018-03-21T13:00:16Z (GMT). No. of bitstreams: 1 viniciussacramentopacheco.pdf: 1524403 bytes, checksum: da3bc47331a9b9d21aceffe2209ed60f (MD5) Previous issue date: 2017-08-04<br>Lippia alba (Mill.) N.E. Brown (Verbenaceae) é uma das espécies medicinais mais amplamente utilizadas no Brasil. Nas últimas décadas, grande número de trabalhos vem investigando e comprovando os efeitos farmacológicos dos componentes encontradas no óleo essencial dessa planta. Estudos relacionados à genômica demonstram a ocorrência de poliploidia natural na espécie, condição que pode interferir na composição e produção dessas substâncias. Em contrapartida, fatores ambientais, como a irradiância e disponibilidade hídrica, também são importantes modeladores da biossíntese dessas moléculas, podendo interagir com o fator genético. Diante do exposto, investigou-se os efeitos de níveis contrastantes de irradiância, a 100% (pleno sol) e 30%( à sombra), durante as épocas seca e chuvosa de cultivo, sobre as trocas gasosas e seus posteriores efeitos sobre o crescimento e a produção de óleo essencial em acessos de L. alba que possuíam três níveis de ploidia distintos (Di-; Tetra- e Hexaploide). Para a maioria dos parâmetros de trocas gasosas, as plantas cultivadas à sombra apresentaram valores menores quando comparados às plantas cultivadas a pleno sol, independentemente da época de cultivo. Em ambos os níveis de irradiância, o acesso tetraploide apresentou os menores valores para a fotossíntese liquida, bruta, fotorrespiração, condutância estomática e taxa de transporte de elétrons para carboxilação e oxigenação. Acessos cultivados à sombra apresentaram respostas tipicamente associadas a essa condição de luminosidade, com maior área foliar especifica e unitária, alocação preferencial de biomassa em parte aérea e maior conteúdo de clorofilas, bem como valores menores em biomassa de raiz, massa total e taxa assimilatória liquida. Em comparação aos cultivados a pleno sol, todos os acessos cultivados à sombra apresentaram conteúdo de óleo essencial , em média, 40% menor. Quando cultivados a pleno sol o acesso diploide apresentou o maior conteúdo de óleo essencial, que foi em média 150% maior, que o observados para os acessos tetra- e hexaploide. À sombra, o conteúdo de óleo essencial do acesso diploide foi 120% maior que os demais. Entretanto, nessa condição, este acesso apresentou a menor biomassa total. Os resultados encontrados permitem concluir que o acesso diploide, independentemente da irradiância em que foi cultivado, apresento o maior rendimento da produção de óleo essencial, sugerindo maior atividade das vias do metabolismo secundário, reduzindo o acúmulo de biomassa sob baixa irradiância.<br>Lippia alba (Mill.) N.E. Brown (Verbenaceae) is one of the most widely used medicinal species in Brazil. In the last decades, a great number of works have been investigating and proving the pharmacological effects of the components found in the essential oil of this plant. Studies related to genomics demonstrate the occurrence of natural polyploidy in the species, a condition that may interfere in the composition and production of these substances. In contrast, environmental factors, such as irradiance and water availability, are also important modellers of the biosynthesis of these molecules, and may interact with the genetic factor. Considering the above, the effects of contrasting levels of irradiance, at 100% (full sun) and 30% (in the shade), during the dry and rainy seasons of cultivation, on the gas exchanges and their subsequent effects on growth were investigated and the production of essential oil in L. alba accesses that had three distinct levels of ploidy (Di-, Tetra- and Hexaploid). For most gaseous exchange parameters, shade-grown plants presented lower values when compared to plants grown in full sun, regardless of the growing season. In both levels of irradiance, tetraploid access presented the lowest values for liquid photosynthesis, crude, photorespiration, stomatal conductance and electron transport rate for carboxylation and oxygenation. Shade - grown accesses presented responses typically associated to this luminosity condition, with a greater specific and unitary leaf area, preferential allocation of biomass in aerial part and higher content of chlorophylls, as well as lower values in root biomass, total mass and net assimilation rate. Compared to those grown in the full sun, all accesses cultivated in the shade had an essential oil content, on average, 40% lower. When cultivated in full sun the diploid access had the highest essential oil content, which was on average 150% higher than that observed for the tetra- and hexaploid accessions. In the shade, the essential oil content of the diploid access was 120% greater than others accessions. However, in this condition, this access presented the lowest total biomass. The results show that diploid access, irrespective of the irradiance in which it was cultivated, presents the highest yield of essential oil production, suggesting higher activity of the secondary metabolism pathways, reducing the accumulation of biomass under low irradiance.

The medicinal plants are included within the wide diversity of the MaciÃo de Baturità ecosytem and they are an important component of traditional medicine of this region. However, scientific information that may contribute to the increase in the cultivation of these plants are still rare, particularly at conditions of the State of CearÃ. The overall objective of this project is to evaluate the development and the production of alecrim pimenta (Lippia origanoides) at conditions of MaciÃo de BaturitÃ, CearÃ. Two experiments were conducted, the first during the dry season of 2013 (August to November) and the second during the rainy season of 2014 (February to May). The experiment was corned out in completely randomized design with split plots, being the plots defined by two seasons (drought and rainy), the subplot formed by light conditions (greenhouse and full sun), and the subsubplots formed by four evaluation times (0, 40, 80 and 120 days after transplanting). Five replications were used, each one represented by a pot of 20 L containing a plant. The following variables were evaluated: leaf area, plant height, stem diameter, dry matter production, leaf gas exchange, chlorophyll content, mineral nutrients, organic solutes, and essential oils. The alecrim pimenta grows well in the Baturità region, with yields of biomass and essential oil similar to those observed in other studies. The cultivation in greenhouse (50% of solar radiation) changed the pattern of development of alecrim pimenta, resulting in plants with better overall appearance, taller, with larger leaves, higher specific leaf area, less developed root system, and lower root/shoot ratio, regardless of the season of cultivation. The production of dry biomass of leaves and total did not differ between the two environments (light conditions) after 120 days cultivation, regardless of the period of year. During the drought season there was a strong influence of the light condition on stomatal conductance and transpiration, with the values being lower in full sun environment, suggesting stomatal sensitivity to climate conditions in this species. Plants grown in greenhouse showed, in general, higher levels of nutrients and nitrogen compounds (N-aminossolÃveis), compared to plants under full sunlight, regardless of the cropping season.<br>Dentre os vegetais que compÃem ampla diversidade do MaciÃo de Baturità se inserem as plantas medicinais, sendo estas, principais componentes da medicina tradicional. No entanto, informaÃÃes cientÃficas que possam contribuir para o incremento do cultivo dessas plantas ainda sÃo raras, particularmente nas condiÃÃes edafoclimÃticas do Estado do CearÃ. Objetivou-se com o presente trabalho, avaliar o desenvolvimento e o potencial produtivo do alecrim pimenta (Lippia origanoides) nas condiÃÃes edafoclimÃticas do MaciÃo de BaturitÃ, CearÃ. Foram realizados dois experimentos, sendo o primeiro durante o perÃodo seco de 2013 (agosto a novembro) e o segundo durante o perÃodo chuvoso de 2014 (fevereiro a maio). O experimento foi conduzido seguindo um delineamento inteiramente casualizados com parcelas subsubdivididas, sendo as parcelas definidas pelas duas estaÃÃes (seca e chuvosa), as subparcelas formadas pelas condiÃÃes de luminosidade (telado e pleno sol), e as subsubparcelas pelas quatro Ãpocas de avaliaÃÃo (0, 40, 80 e 120 dias apÃs o transplantio). Foram utilizadas cinco repetiÃÃes, sendo cada repetiÃÃo representada por um vaso de 20 litros contendo uma planta. Foram avaliadas as seguintes variÃveis: Ãrea foliar, altura da planta, diÃmetro do caule, massa seca dos diferentes ÃrgÃos vegetais, trocas gasosas, teores de clorofila, teores de minerais, solutos orgÃnicos e rendimento do Ãleo essencial. O alecrim pimenta desenvolveu-se bem na regiÃo do MaciÃo de BaturitÃ, com produtividades de biomassa e de Ãleo essencial similares Ãs observadas em outros estudos. O cultivo em telado alterou o padrÃo de desenvolvimento do alecrim pimenta, resultando em plantas com melhor aparÃncia geral, mais altas, com folhas maiores, maior Ãrea foliar especÃfica, menor desenvolvimento do sistema radicular e menor relaÃÃo raiz/parte aÃrea, independentemente da Ãpoca de cultivo. A produÃÃo de massa seca de folhas e total nÃo diferiu entre os dois ambientes apÃs 120 dias de cultivo, independentemente do perÃodo do ano. Houve forte influÃncia do ambiente de cultivo no perÃodo seco, sobre a condutÃncia estomÃtica e a transpiraÃÃo, com os valores sendo menores no ambiente a pleno sol, sugerindo a sensibilidade estomÃtica da espÃcie Ãs condiÃÃes atmosfÃricas do perÃodo. As plantas cultivadas em telado apresentaram, de forma geral, maiores teores de nutrientes minerais e de compostos nitrogenados (N-aminossolÃveis), em comparaÃÃo Ãs plantas submetidas a pleno sol, independente do Ãpoca de cultivo.

Made available in DSpace on 2015-03-26T13:39:55Z (GMT). No. of bitstreams: 1 texto completo.pdf: 5375296 bytes, checksum: c7ea1e4a6904287d34cf3114d66369d3 (MD5) Previous issue date: 2013-03-18<br>Brazil is the largest producer of passion fruit, with 920.158 million tonnes achieved during the year 2010, an area of 62,243 ha (IBGE, 2012). The passion fruit is the most cultivated in Brazil, with over 90% of the planted area and volume sold across the country, 60% of this production is intended for the fresh market. However, the soil diseases reduces the life crop, forcing the crop traveling into practice. The genetic resistance may prevent the premature death of the plants, providing training to healthier crops, uniform and enduring. Among the alternatives to be fetched, we highlight the use of wild species as resistant rootstocks. This study aimed to quantify the influence on the agronomic characteristics of yellow passion fruit (Passiflora edulis Sims) rootstocks of wild P. mucronata and P. gibertii. The characteristics evaluated were: percentage of graft survival, plant height, height of first flowering, number of leaves, number of nodes, diameter of the rootstock and grafting, histological analysis of the graft region, rate of occurrence of us days to flowering, gas exchange and physical and chemical qualities of the fruit. It was observed that the rootstock P. mucronata showed better conformation anatomical and histological region exertia and positively influenced the number of leaves, number of nodes, the time of first flowering, number of flowers and the rate of occurrence of us. When wild species were used as rootstock, developed these early buds and fruits originated more elongated than the non-grafted, but within the standards of marketing. The species P. mucronata showed the best performance as a rootstock.<br>O Brasil é o maior produtor mundial de maracujá, com 920.158 mil toneladas alcançadas durante o ano de 2010, numa área de 62.243 ha (IBGE, 2012). O maracujá amarelo é o mais cultivado no Brasil, com mais de 90% de área plantada e volume comercializado em todo o país; 60% dessa produção se destinam ao mercado in natura. No entanto, as doenças do solo reduzem a vida útil das lavouras, forçando à prática do cultivo itinerante. A resistência genética pode evitar a morte prematura das plantas, fornecendo formação de lavouras mais sadias, uniformes e longevas. Entre as alternativas a serem buscadas, destaca-se a utilização de espécies silvestres resistentes como porta-enxertos. Este trabalho buscou quantificar a influência sobre as características agronômicas do maracujazeiro-amarelo (Passiflora edulis Sims) dos porta-enxertos silvestres P. mucronata e P. gibertii. As características avaliadas foram: porcentagem de sobrevivência dos enxertos, altura da planta, altura da primeira floração, número de folhas, número de nós, diâmetros do porta-enxerto e do enxerto, análise histológica da região do enxerto, taxa de ocorrência de nós, dias até a floração, trocas gasosas e qualidades físicas e químicas dos frutos. Foi observado que o porta enxerto P. mucronata apresentou melhor conformação anatômico-histológica da região da exertia e influenciou positivamente o número de folhas, o número de nós, a altura da primeira floração, o número de flores e a taxa de ocorrência de nós. Quando as espécies silvestres foram empregadas como porta-enxerto, essas desenvolveram botões florais mais precocemente e originou frutos mais alongados que os pés-francos, porém dentro dos padrões de comercialização. A espécie P. mucronata foi a que apresentou o melhor desempenho como porta-enxerto.

I värme- och kraftvärmeverk förbränns olika typer av bränslen för produktion av el och fjärrvärme. Vid förbränningen bildas rökgaser som innehåller föroreningar, till exempel tungmetaller, från bränslet. Anläggningarna har ofta krav på utsläpp både via rökgaserna och avloppsvatten. Rökgaserna renas därmed genom olika tekniker var av en vanlig teknik är rökgaskondensering. Vid rökgaskondenseringen bildas en vätska, kallad rökgaskondensat, som delvis innehåller tungmetaller från bränslet. Rökgaskondensatet måste renas innan det kan lämna anläggningen och det görs bland annat med tungmetalljonbytare. Jonbytarmassan i tungmetalljonbytarkolonnerna behöver bytas ungefär två gånger per driftsäsong då den inte längre kan binda mer tungmetaller. Detta är en kostnad för värme- och kraftvärmeverken som de vill minimera. I denna studie undersöktes om lokal provtagning och analys på ett kraftvärmeverk av ett antal utvalda tungmetaller i rökgaskondensat är en bra metod för att optimering av reningssteget med tungmetalljonbytare. Samt om detta kan säkerställa att miljökraven för tungmetaller i det renade rökgaskondensatet uppfylls. Med optimering avses att jonbytarmassornas fulla kapacitet utnyttjas, d.v.s. att byten av jonbytarmassor kan reduceras utan att riskera otillåtna halter av tungmetaller i de renade rökgaskondensatet till följd av att jonbytarmassorna använts för länge. Även tiden som behöver avsättas för lokal provtagning och analys dokumenterades. I dagsläget sker analyser hos ackrediterade laboratorium där det tar drygt två veckor att få resultatet och under väntetiden kan mycket på anläggningen förändras. En verifiering av resultaten från studien gjordes mot resultat från ett sådant. I denna studie undersöktes lokal provtagning och analys med mätinstrumentet FREEDD som bygger på tekniken kvartskristall mikrobalans (QCM-teknik). Andra alternativ för lokal analys har inte undersökts här.  Resultatet visade att det i dagsläget är svårt att med lokal provtagning optimera reningssteget med jonbytarmassor samt kontrollera utsläppen av tungmetaller via det renade rökgaskondensatet. Korrigeringar hos mätinstrumentet och provpunkterna behöver göras för att få pålitligt resultat. Tiden som behöver avsättas för provtagning och analys beror på vilken metall som ska analyseras då tiden för preparering av prov varierar. Men om det kan möjliggöra att anläggningarna kan använda jonbytarmassorna längre samt får kontroll på utsläppen via det renade rökgaskondensatet kan det vara lönsamt att avvara den tiden.<br>In heating and combined heat and power plants, different types of fuels are burned to produce electricity and district heating. During the combustion flue gases containing pollutants, such as heavy metals, are formed from the flue. The plants have requirements for low emissions, both from the flue gases and the wastewater. The flue gases are purified by various techniques and a common technique is flue gas condensation. During the flue gas condensation, a liquid called flue gas condensate, is formed, which partly contains heavy metals from the flue. The flue gas condensate must be cleaned before it can leave the plant. A step in the purification of the flue gas condensate is usually heavy metal ion-exchanger. The ion-exchange mass in the heavy metal ion-exchange columns needs to be changed approximately twice per operating season as it no longer has room to bind more heavy metals. This is an expensive cost for the heating and combined heat and power plants that they want to minimize. This study investigated whether local sampling and analysis at a cogeneration plant of a number selected heavy metals in flue gas condensate is a good method for optimizing the purifications step with heavy metal ion-exchangers. And if this can ensure that the environmental requirements for the heavy metals in the purified flue gas condensate are met. Optimization means that the full capacity of the ion-exchange masses is utilized, i.e. that the exchange of ion-exchange masses can be reduced without risking unauthorized levels of heavy metals in the purified flue gas condensate as a result of the ion exchange masses being used for too long.  The time needed for local sampling and analysis was also documented. At present, analyzes are done at accredited laboratories where it takes over two weeks to get the result and during that time much can be changes at the plant. A verification of the result of the study was also made against the result of an accredited laboratory. In this study, local analysis was made with the measuring instrument FREEDD which is based on quartz crystal microbalance (QCM-technology). Other options for local sampling and analysis have not been investigated. The result showed that, in the present, it is difficult to optimize the purification step with ion-exchange masses and check emissions of heavy metals with the purified flue gas condensate. To obtain reliable result, corrections to the measuring instrument and test points need to be made. The time that needs to be set aside for sampling and analysis depends on the metal, as the time for sample preparation varies.  But if it can enable the plants to use the ion-exchange masses longer and gain control of the emissions of heavy metals with the purified flue gas condensate, it can be profitable to save that time.

Ziel dieser Arbeit war es, das Verständnis über Reaktionen von Tomaten auf limitiertes Nährstoffangebot zu verbessern. In der Kontrollbehandlung (100% Biomassewachstum) wurden Pflanzen ohne Nährstofflimitierung kultiviert. Bei den Mangelvarianten wurde entweder K, Mg oder N kontinuierlich in Raten angeboten, die das Wachstum auf etwa 80% (leichter Mangel) oder 60% (starker Mangel) der Kontrolle reduzierten. Dieser Versuchsansatz ermöglichte es, pflanzliche Reaktionen auf eine gut definierte Intensität von Mangel an K, Mg und N zu vergleichen. Nährstofflimitierung veränderte die Biomasse- und Nährstoffallokation auf die verschiedenen Pflanzenorgane, wobei diese Veränderungen sich je nach Nährstoff unterschieden, aber nicht von der Intensität des Mangels abhängig waren. Die Wirkungen von Nährstofflimitierung auf morphologische Wurzel- und Sprosseigenschaften waren ebenfalls Nährstoff-spezifisch und nicht abhängig von der Intensität des Mangels. Die Wirkungen auf die Fruchtqualität, z.B. den Gehalt an Zuckern, Lycopin und Vitamin C waren Nährstoff-spezifisch und bei einigen Parametern auch von der Intensität des Mangels abhängig. Die Pflanzenreaktionen auf Mg-Mangel wurden in größerem Detail untersucht. In den ersten 6 Tagen nach Beginn der Limitierung nahmen die Mg-Konzentrationen in allen Organen stark ab, ohne Wirkung auf das Wachstum und die Photosynthese. Mangel erhöhte die Blattzuckergehalte, aber die Zuckerakkumulation stand in keiner Beziehung zur Photosyntheserate. Diese nahm erst ab, wenn die Blatt-Konzentrationen auf Werte unterhalb von 0,1 bis 0,2 mg Mg g-1 Frischmasse abgesunken waren. In Mg-Mangelpflanzen akkumulierten Zucker in den Sourceblättern sogar wenn das Source/Sink-Verhältnis in den Pflanzen durch Beschattung der basalen Blätter stark verringert wurde. Das stimmt mit der Annahme überein, dass Mg-Mangel aufgrund einer Inhibierung der Phloembeladung den Zuckerexport aus den Blättern verringert.<br>This thesis aims to increase our understanding about plant responses to K, Mg and N limitation and their relationship with fruit quality of tomato. In the control treatment (100% biomass growth), plants were grown at high nutrient concentration. In the nutrient-limitation treatments, either K or Mg or N was supplied continuously at rates, which reduced biomass growth to about 80% (mild deficiency) or 60% (severe deficiency) of the control. This experimental approach allowed comparing long-term plant responses to deficiency of K, Mg or N at well-defined intensities of nutrient limitation. Nutrient limitation was associated with changes of biomass and nutrient allocation among various plant organs, whereby these changes were nutrient specific (e.g., biomass allocation to leaves was increased in Mg deficient plants, and decreased in N deficient plants), but not much dependent on the intensity of nutrient limitation. Effects of nutrient limitation on root and shoot morphological traits were also nutrient-specific and independent on the intensity of deficiency. Effects of nutrient limitation on fruit quality, e.g, sugar, lycopene and ascorbic acid content, were also nutrient-specific, and for specific parameter dependent on the intensity of deficiency. Responses to Mg deficiency were studied in more detail. In the first 6 days after start of Mg limitation, Mg concentrations in all plant organs drastically decreased without any effects on growth and leaf photosynthetic rates. Mg-deficiency increased leaf sugar concentrations, but sugar accumulation was not directly related to leaf photosynthesis which only decreased after leaf Mg concentrations were below 0.10 to 0.20 mg Mg g-1 leaf fresh mass. In Mg-deficient plants, sugars accumulated in source leaves even when the source/sink ratio was strongly decreased by shading of basal leaves. This is in accordance with the suggestion that sugar export is reduced due to inhibition of phloem loading.

Orientador: João Domingos Rodrigues<br>Banca: Elizabeth Orika Ono<br>Banca: Fernando Broetto<br>Banca: Teresinha Costa S.de Albuquerque<br>Banca: Barbara Franca Dantas<br>Resumo: A videira por ser originária de regiões de inverno rigoroso, apresenta mecanismo de dormência que conferem condições de sobrevivência durante o período frio. Contudo, esta mesma espécie também é cultivada em condições tropicais, cuja ausência de estação com baixas temperaturas favorece seu contínuo desenvolvimento vegetativo, fazendo-se necessário estabelecer um repouso, que normalmente é promovido com a redução do fornecimento de água, através do controle da irrigação. No entanto, este processo, apesar de ter o mesmo objetivo da dormência estabelecida pelo frio, apresenta mecanismos fisiológicos e bioquímicos diferentes. Este trabalho teve o objetivo de avaliar características fisiológicas e bioquímicas de plantas de Vitis vinifera L. cv. Thompson Seedless submetidas às condições de frio e deficiência hídrica, assim como sua influência na brotação de gemas. As plantas foram conduzidas em casa-de-vegetação e submetidas aos seguintes tratamentos: 1. Controle (25-30oC / 60-70% U.R. em capacidade de campo - cc); 2. Deficiência Hídrica (25-30oC / 60-70% U.R. a uma tensão de água no solo entre -80 a -100 kPa); 3. Frio (5-13oC / 60-70% U.R. em câmara climatizada e em cc), por um período de até 90 dias, sendo cada parcela de plantas avaliada e amostrada a cada 15 dias, para em seguida ser reconduzida às condições de Controle (25-30oC/60-70%U.R em cc), onde permaneceram até a brotação. O delineamento foi inteiramente casualizado, em esquema de parcela subdividida (3 x 6); sendo a parcela representada pelos três tratamentos; enquanto a subparcela representada pelos seis tempos de permanência que as plantas foram submetidas aos tratamentos (15, 30, 45, 60, 75 e 90 dias após o tratamento - DAT). O número de repetição variou de acordo com o tipo de característica avaliada (destrutiva e não destrutiva) e cada unidade experimental foi constituída... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The vine is from cold winter regions and because this has dormancy mechanism conferring survival conditions during the cold period. However, these species are also cultivated in tropical conditions and absence of season with low temperatures increase vegetative growth, and because this is necessary to establish a dormant which usually is promoted with reducing water supply through irrigation control. But while used in place of cold dormancy, irrigation control has different biochemical and physiological mechanisms, this way, the aim were to evaluate physiological and biochemical characteristics of Vitis vinifera L. cv. Thompson Seedless plants submitted to cold and drought conditions, as well as its influence on bud break. Plants were growing in a green house and treated as follows: 1. Control (25-30oC / 60-70% RH at field capacity - cc), 2. Water deficiency (25-30oC/60-70% RH at a soil water tension between -80 to -100 kPa) 3. Cold (5-13oC/60-70% RH in an growth chamber acclimatized at cc), for a period up to 90 days, and plants portion were sampled and evaluated each 15 days, to then be brought back to Control conditions (25-30oC/60-70% RH in cc), where they remained until budding. The design was completely randomized in a split plot design (3 x 6) being three main treatments and sub plots constituted by six permanence time which plants were treated (15, 30, 45, 60, 75 and 90 days after treatment - DAT). The repetition number varied according characteristic evaluated (destructive and non destructive) and each plant represented one experimental unit. The following physiological characteristics were evaluated: rate of net CO2 assimilation... (Complete abstract click electronic access below)<br>Doutor

The aim of this project is to select appropriate heat exchangers out of available gas-gas heat exchangers for used in a proposed power plant. The heat exchangers are to be used in the power plant for the purposes of waste heat recovery, recuperation and intercooling.In selecting an optimum heat exchanger for use, the PCHE was identified as the best candidate for waste heat recovery and recuperation. In order to ascertain the viability of this assertion the PCHE was designed and a 1D modeling performed in MATLAB using the conditions that the heat exchanger for waste heat recovery would be subjected to. The choice of using the conditions that the waste recovery heat exchanger would be subjected to was due to the fact that, it is the heat exchanger that would be subjected to much harsh conditions (thus higher temperatures of up to 650 ºC). The PFHE was also designed and similarly a 1D modeling performed in MATLAB. The decision to consider the design of the PFHE was to offer a platform to compare and contrast the performance of the PCHE in order to have a strong basis for deciding on whether to stick to the choice for the PCHE or otherwise.The results obtained from the 1D modeling of the design of the heat exchangers indicates that the PCHE performed better with regards to pressure drops across the heat exchangers (with values of 1.17 and 2.47 % for the cold and hot sides respectively), compactness (with a value of 1300 m2/m3 for the PCHE compared to the 855 m2/m3 recorded from the PFHE), however the PFHE recorded higher heat transfer coefficients, and a subsequent higher overall transfer coefficient.Results obtained from the simulation of the 3D model buttress the decision to employ the PCHE as heat exchangers to be used for waste heat recovery and recuperation as a wise one, with an effectiveness of 0.94 as against the design value of 0.90, and with pressure drops as desired of the optimum heat exchanger.

The perennating organ, the rhizome, was chosen for examination of response to anoxia in monocotyledonous species known to differ in tolerance of flooding. Survival of prolonged anoxia was monitored in the wetland species (Acorus calamus, Iris pseudacorus. Phragmites australis, Schoenoplectus lacustris and Typha latifolia), and the dryland species (Iris germanica). Fermentation capacity was estimated in the anoxic and post-anoxic phases together with ethanol and lactate accumulation. Under N2 accumulation of ethanol took place in all species; lactic fermentation was of less importance. There was a steady-state condition of low ethanol accumulation in the wetland species, where an apparent equilibrium of production and elimination from rhizome tissue was reached. In contrast, the dryland species showed a continuous increase in ethanol accumulation during oxygen deprivation. Catalase and superoxide dismutase activities were measured during the post-anoxic recovery phase in their role as enzymatic defences against oxygen toxicity. In rhizomes of the anoxia tolerant species A. calamus. S. lacustris and I. pseudacorus, no changes in catalase activity were observed. However, the relatively anoxia intolerant Glyceria maxima, Juncus effusus and I.germanica exhibited significant increases in catalase activity. To investigate whether catalase (acting in its 'peroxidatic' mode) was perhaps here involved in an ethanol oxidation reaction, anaerobic rhizomes of G.maxima were exposed to ethanol vapour: considerable increases in catalase activity were recorded. It is proposed that acetaldehyde thus produced may be a source of post-anoxic injury. Superoxide dismutase activity in I.pseudacorus rhizomes rose significantly during anoxia, while small increases were found in the less anoxia tolerant I.germanica and a drop in activity was recorded in G.maxima. It is suggested that I.pseudacorus may be less susceptible to post-anoxic injury by means of oxygen toxicity, while in the other species oxidative damage on return to air may contribute to anoxia intolerance.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior<br>No cultivo de bananeiras faz-se o desbaste de brotaÃÃes e o corte de plantas que jà frutificaram gerando resÃduos lignocelulÃsicos. Os pseudocaules cortados formam a maior porÃÃo desse resÃduo e servem como meio para proliferaÃÃo de pragas na cultura. Na utilizaÃÃo industrial desse resÃduo fibroso gera-se o LÃquido do Pseudocaule da Bananeira (LPCB). Este estudo teve por objetivo avaliar efeitos do LPCB combinado com soluÃÃo nutritiva nos parÃmetros fisiolÃgicos, no crescimento e na nutriÃÃo de mudas da cultivar Prata AnÃ. Mudas micropropagadas foram cultivadas em colunas de PVC de 20 cm de diÃmetro por 65 cm de altura contendo cinco camadas de Argissolo (0-10, 10-20, 20-30, 30-40 e 40-60 cm) e submetidas a cinco dosagens do LPCB (0, 288, 576, 864 e 1152 mL), representados por concentraÃÃes volumÃtricas de Ãgua e o resÃduo (100:0, 75:25, 50:50, 25:75, 0:100, v:v), combinadas com duas concentraÃÃes da soluÃÃo nutritiva de Hoagland (uma forÃa e meia forÃa), utilizando-se cinco repetiÃÃes em cada tratamento. ApÃs 60 dias de cultivo determinou-se a taxa fotossintÃtica, a condutÃncia estomÃtica e o teor de clorofila nas folhas e, na ocasiÃo da colheita, aos 68 dias, obteve-se dados de altura e diÃmetro do pseudocaule, nÃmero de folhas, peso fresco e seco das raÃzes e das partes aÃreas e analisaram-se os teores de N, K e Na das raÃzes e das partes aÃreas das bananeiras. Em camadas de solo avaliaram-se caracterÃsticas microbiolÃgicas e quÃmicas. Os resultados indicaram que LPCB afeta a dinÃmica de nutrientes no solo, favorecendo o acÃmulo de Na e K numa camada mais prÃxima da superfÃcie e reduzindo o pH do solo em camadas sub-superficiais. A aplicaÃÃo do resÃduo incrementou a biomassa microbiana e a respiraÃÃo edÃfica. Maiores doses do resÃduo resultaram no menor crescimento e acÃmulo de biomassa da parte aÃrea. A aplicaÃÃo de doses crescentes do resÃduo resultou no incremento da taxa fotossintÃtica e na reduÃÃo da condutÃncia estomÃtica, transpiraÃÃo e teor de clorofila das folhas das bananeiras.<br>The cultivation of banana trees generate lignoselulosic residue by cutting shoots and the plants after bunch collection. The pseudo-stem represents the largest portion of that residue and serves as a medium for the proliferation of pests in banana field. By industrial processing of that fibrous residue is also generated expressive volume of Netâs speudo-stem (LPCB). This study aimed to evaluate the effects LPCB combined with nutrient solution on physiological parameters, shot growth and nutrition of seedlings of the cultivar âPrata AnÃâ. Plantlets were grown on PVC columns of 20 cm diameter by 65 cm high filled with Ultisol from five layers (0-10, 10-20, 20-30, 30-40 and 40-60 cm) and subjected to five dosages of LPCB (0, 288, 576, 864 and 1152 mL, represented by volumetric combinations of water and LPCB (100:0, 75:25, 50:50, 25:75, 0:100, v:v), combined with two concentrations of Hoagland nutrient solution (one strength and half strength), using five replicates for each treatment. After 60 days of plant cultivation the stomata conductance, photosynthetic and chlorophyll contents in leaves were determined and, at the time of harvest, 68 days, were measured plant height and pseudo-stem diameter, counted leaves, determined fresh and dry weight of roots and aerial parts and analyzed N, K and Na contends in roots and aerial parts of banana plants. In layers of soil were evaluated microbiological and chemical characteristics. The results indicated that LPCB affects the dynamics of nutrients in the soil, favoring the accumulation of Na and K in a layer near the surface and reducing the pH in subsurface layers. The LPCB application rates increased microbial biomass and edaphic respiration. A higher dosage of that residue inhibits the plantlet growth and dry weight accumulation. The increasing of LPCB dosages promoted higher photosynthetic rate, but reduces stomata conductance, transpiration and chlorophyll content in leaves of banana plants.

Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2016-04-26T11:31:40Z No. of bitstreams: 1 texto completo.pdf: 828935 bytes, checksum: 1db7e181e01f2e3911c0020c68d4f833 (MD5)<br>Made available in DSpace on 2016-04-26T11:31:40Z (GMT). No. of bitstreams: 1 texto completo.pdf: 828935 bytes, checksum: 1db7e181e01f2e3911c0020c68d4f833 (MD5) Previous issue date: 2015-02-19<br>Fundação de Amparo à Pesquisa do Estado de Minas Gerais<br>A Anthracnose, causada pelo fungo Colletotrichum truncatum, é uma das doenças de soja mais importantes no mundo, mas não há estudos avaliando as alterações fisiológicas neste patossistema. Portanto, uma abordagem para avaliar os eventos que ocorrem no local da infecção e perto da área infectada na folha, ao longo do tempo, contribuirá para uma melhor compreensão da interação planta-hospedeiro e atividade fotossintética. Assim, o presente estudo buscou investigar parâmetros de fluorescência da clorofila a (Chl a) na área da lesão e uma área adjacente, associando os ás trocas gasosas e avaliação de pigmentos fotossintéticos em plantas de soja inoculadas ou não inoculadas com C. truncatum. O parâmetros de trocas gasosas não foram alterados em plantas inoculadas. No entanto, ocorreu redução da concentração de Chl a, Ch b e da Chl total (a + b) nas plantas inoculadas as 72 e 144 horas após a inoculação (hai), com redução máxima à 144 hai de 24% para Chl a, que demonstrou ser mais sensível que a Chl b, ocasionando, portanto, a redução da razão Chl a/ Chl b. Também foi encontrado queda em valores de fluorescência da clorofila a como, Fluorescência inicial (Fo), Fluorescência máxima (Fm), Eficiencia quântica máxima do fotossistema II (Fv/Fm), Rendimento quântico de dissipação de energia regulada Y(NPQ) e coeficiente não- fotoquímico (qN), e um acréscimo no Rendimento quântico efetivo do PSII Y(II), Rendimento quântico de dissipação de energia não regulada (NO) e coeficiente fotoquímico (qP) nas área sintomática de plantas inoculadas. Entretanto esses parâmetros sofreram pequenas alterações nas áreas adjacentes das plantas inoculadas, diferindo apenas em alguns tempos. Demonstrando, dessa forma, um menor efeito do patógeno nas áreas adjacentes.<br>Anthracnose, caused by Colletotrichum truncatum, is one of the most important soybean diseases worldwide. However, there are no studies evaluating the physiological changes affecting this pathossystem. Therefore, one approach to evaluating events that occur at the site of infection and near the infected area on the leaf, over time, will contribute to a better understanding of the host-plant interaction and photosynthetic activity. The present study aimed to investigate chlorophyll a fluorescence parameters at injured and adjacent areas and the related changes in gas exchange and evaluation of photosynthetic pigments in soybean plants inoculated or non-inoculated with C. truncatum. There were no significant differences regarding gas exchange parameters for inoculated plants. However, there was a reduction in the concentration of Chl a, Chl b e Chl total (a + b) of inoculated plants in the 72 and 144 hours after inoculation (hai). Reduction in chlorophyll a fluorescence parameters to as initial fluorescence (Fo), maximal fluorescence (Fm), maximal photosystem II quantum yield (Fv/ Fm), quantum yield of regulated energy dissipation Y (NPQ) and coefficient non-photochemical (qN), and an increase in the Effective PSII quantum yield Y (II), quantum yield of non- regulated energy dissipation (NO) and photochemical coefficient (qP) in the symptomatic area plants inoculated. However, these parameters have undergone minor adjacent areas of inoculated plants, differing only in a few days. Demonstrating a smaller effect of the pathogen in adjacent.

Seasonal patterns of stomatal activity, plant-temperature-based drought stress indices, growth and grain yield of two pearl millet (Pennisetum americanum (L.) Leeke) parental lines and their F₁ hybrid were studied under a sprinkler irrigation gradient system in 1985 and 1986 in Tucson, Arizona. Physiological and morphological measurements of stressed and nonstressed plants were made periodically starting at the panicle initiation stage. Well-defined trends in stomatal conductance (Cg), transpiration (Tr), and photosynthetic (Pn) rates of nonstressed plants were observed over the seasons. Tr increased from 5ug H₂O cm⁻²s⁻¹ at early panicle development stage to a peak of up to 30 ug cm⁻²s⁻¹ at flowering and declined to 10 ug cm⁻²s⁻¹ at maturity. Pn of well-irrigated plants was highest (26 uMoles CO₂ m⁻²s⁻¹) at early flag leaf appearance stage and declined slowly to 14 uMoles m⁻²s⁻¹ at maturity. In extremely stressed plants, Cg, Tr and Pn were highest early in the seasons, lowest in the middle of the seasons, and slightly increased towards the end of the seasons. The seasonal trends in stomatal response depended on the stage of plant growth and vapor pressure deficit of the air. Transpiration efficiency was highest at partial stomatal closure. Morphologically, the F₁ hybrid was more like its male than its female parent. The female parent produced less dry matter, had thinner leaves and greater ratio of leaf to stem dry matter, and yielded less grain than the other genotypes. The results indicated that leaf:stem ratio can be a useful selection criterion of drought avoiding genotypes. Plants that develop stems and heads rapidly (low leaf:stem ratio) are more desirable under stress than plants that tend to become leafy. Decreases in Tr, Pn, dry matter and grain yield due to stress could be assessed with canopy or leaf temperature, canopy minus air or leaf minus air temperature, and crop (CWSI) or leaf (LWSI) water stress indices. CWSI and LWSI were more desirable in assessing stress than the other indices. CWSI is effective in assessing the magnitude of stress in a crop stand, while LWSI may be useful in situations where use of the infrared thermometer is difficult.

Ozone is known to be the most widespread phytotoxic air pollutant. Ozone causes visible injury, reductions in photosynthesis, growth, and yield. Plant response to ozone may vary with species, varieties, and physiological age. Comparison between sensitive and tolerant cultivars has a key role in assessing ozone damage, investigating the sites of cellular injury, and identifying ozone tolerance mechanism. The objectives of this study were to investigate the effects of high ozone concentration (200 ppb) as well as ambient ozone concentrations (under field conditions) on net CO2 assimilation and PSII function in plants with different sensitivities to ozone. Two species of plants, tobacco (Nicotiana tabacum L.) and black cherry (Prunus serotina) were studied. Gas exchange analysis and chlorophyll fluorometry were utilized to characterize physiological function. Two tobacco cultivars, Bel-B and Bel-W3, tolerant and sensitive to ozone, respectively, were grown in a greenhouse supplied with charcoal filtered air and then exposed to 200 ppb ozone for 4hr. Effects on chlorophyll fluorescence, net photosynthesis, and stomatal conductance are described. Quantum yield was calculated from chlorophyll fluorescence and the initial slope of the assimilation-light curve measured by the gas exchange method. Only the sensitive cultivar, Bel-W3, developed visible injury symptoms involving up to 50% of the 5th leaf. The maximum net photosynthetic rate of ozone-treated plants of the tolerant cultivar was reduced 40% compared to control plants immediately after ozone fumigation; however, photosynthesis recovered by 24 hr post fumigation and remained at the same level as control plants. In the sensitive cultivar, on the other hand, ozone exposure reduced maximum net photosynthesis up to 50%, with no recovery, apparently causing permanent damage to the photosystem. Reductions in apparent quantum efficiency, calculated from the assimilation-light curve, differed between cultivars. Bel-B showed an immediate depression of 14% compared to controls, whereas Bel-W3 showed a 27% decline. Electron transport rate (ETR), at saturating light intensity, decreased 58% and 80% immediately after ozone treatment in Bel-B and Bel-W3, respectively. Quantum yield decreased 28% and 36% in Bel-B and Bel-W3, respectively. It can be concluded that ozone caused a greater relative decrease in linear electron transport than maximum net photosynthesis, suggesting greater damage to PSII than the carbon reduction cycle. Two different sensitivity classes of black cherry, tolerant and sensitive, growing under natural environmental conditions in Giles County, VA were assessed for physiological responses to ambient ozone concentrations. Additional measurements were made at two other sites near Blacksburg. Leaf gas exchange rates and visible foliar injury were determined monthly during the growing seasons of 2000, 2001, and 2002 to characterize the relationship of injury to altered photosynthetic function. Ambient ozone levels were sufficient to induce visible symptoms which were highly correlated with a reduction in PnMAX (maximum net photosynthetic rate under saturating light conditions) and à CO2 (quantum yield for carbon reduction) only in sensitive black cherry. Electron transport rate (ETR) and quantum yield of PSII (à PSII) were also reduced in sensitive black cherry. Maximum photochemical efficiency (Fv/Fm) in sensitive trees was severely damaged by ambient ozone. There were positive correlations between increasing cumulative ozone concentration and substantial reductions in PnMAX and in à CO2 of sensitive trees compared to tolerant trees. There was a negative correlation between chlorophyll content and percent leaf injury in sensitive black cherry<br>Ph. D.

The gas exchange responses of two cultivars of Hordeum vulgare L., to light, temperature, CO₂ and water stress were investigated in the laboratory. The optimum temperature for net CO₂ assimilation was found to be 25°C and 22.5°C for cv. Clipper and cv. Dayan respectively. Net CO₂ assimilation was reduced at 30°C in cv. Dayan. At low light intensity the highest quantum yield efficiency was 0.051 mol.mol⁻¹ at 30°C for cv. Clipper, and 0.066 mol.mol⁻¹ at 20°C for cv. Dayan. At the same temperature, cv. Clipper had a higher water use efficiency than cv. Dayan, but stomatal conductance for cv. Dayan was higher than cv. Clipper. Stomatal limitation to CO₂ was lowest at the optimum temperature for CO₂ assimilation in both cultivars. Stomata limited CO₂ assimilation in cv. Clipper to a larger degree than in cv. Dayan. Relative stomatal limitation for cv. Clipper at 25°C was 0.280 ± 0.010, and for cv. Dayan at 22.5°C was 0.028 ± 0.011. Short-term exposure to elevated CO₂ concentrations increased CO₂ assimilation in both cultivars, but more so for cv. Clipper. Transpiration rate at elevated CO₂ partial pressures were higher in cv. Dayan than in cv. Clipper. At very high CO₂ (860 μmol.m⁻²s⁻¹) partial pressure water use efficiency in cv. Clipper was higher than cv. Dayan, but at low CO₂ partial pressures water use efficiency in cv. Dayan was higher than cv. Clipper. Water stress reduced the relative leaf water content and net CO₂ assimilation in both cultivars. Cultivar Dayan was more tolerant to water stress, and CO₂ assimilation in this cultivar was less affected by water stress. In both cultivars water stress increased the concentration of chlorophyll a, chlorophyll b, and chlorophyll a+b. The chlorophyll a:b ratio remained relatively constant throughout the stress period. No correlation between relative leaf water content and total carotenoid concentration was observed.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico<br>Salt excess in the soil solution is a serious problem in agriculture, caused mainly by irrigation water, causing soil salinization. These salts, when absorbed affects the growth of plants because of the osmotic effect, reducing the absorption of water in the soil. In order to mitigate the deleterious effects of these salts in plants, several strategies have been developed in order to make plants most tolerant to salt stress. A recent innovation in plant cultivation system is the enrichment of irrigation water with carbon dioxide (carbonation), influencing the commercial crop yield and making them more tolerant to stresses. The objective of this study was to evaluate whether the application of CO2 in irrigation water of melon plants increases the tolerance of the same to salt stress. The experiment was conducted in Pacajus Experimental Field of Embrapa Tropical Agroindustry. The treatments were arranged in a factorial 5 x 3 with four replications, referring to salt solutions at electrical conductivities of (ECw) (0.5, 1.5, 3.0, 4.5 and 6.0 dS m-1) and three treatments with CO2: no CO2 (SC), five applications of CO2 (since flowering until the beginning ripening of fruits) (C1) and two applications of CO2 (since fruit set until the ripening of fruits) (C2). The CO2 was used as a gas injected weekly directly in the irrigation system. The electrical conductivity of the soil saturation extract and CO2 content in the irrigation water were measured at the end of the experiment. The measurement of photosynthesis, stomatal conductance and transpiration occurred throughout plant development. Were also evaluated leaf area, dry weight of leaves and stem + branches, levels of Na+, Cl-, K+ and carbohydrates in the leaves and stems + branches, the number of fruits, productivity, weight, lengths and diameters of the fruit, pulp thickness, total soluble solids and citric acid content. Leaf concentrations of Na+, Cl- and K+ in the leaf and stem + branches were influenced by salinity, with interaction salinity x CO2. For the growth variables: leaf area, dry matter of leaves and stem + branches, there was a significant difference only for the salinity levels. All variables of gas exchange were influenced by salinity, while the stomatal conductance and net photosynthesis were significantly influenced by the application of CO2. The carbohydrate in stem + branches were influenced by the application of CO2. Irrigation with saline water caused a reduction in productivity, number of fruits, lengths of commercial and total fruits. These variables were not influenced by the application of CO2. It is concluded that salinity affected the growth, development and production of melon plants, while the application of CO2 did not minimize the deleterious effect of salts in plants.<br>Um dos grandes problemas enfrentados pela agricultura à o excesso de sais dissolvidos na soluÃÃo do solo, carreados principalmente pela Ãgua de irrigaÃÃo, causando a salinizaÃÃo do solo. Esses sais, ao serem absorvidos, afetam o crescimento das plantas devido ao efeito osmÃtico, dificultando a absorÃÃo de Ãgua no solo. A fim de amenizar os efeitos deletÃrios desses sais nas plantas, vÃrias estratÃgias vÃm sendo desenvolvidas visando tornar as plantas mais tolerantes ao estresse salino. Uma inovaÃÃo recente no sistema de cultivo de plantas à o enriquecimento da Ãgua de irrigaÃÃo com o diÃxido de carbono (carbonataÃÃo), influenciando a produtividade comercial da cultura e tornando-a mais tolerante a estresses. Assim, o objetivo deste trabalho foi avaliar se a aplicaÃÃo de CO2 na Ãgua de irrigaÃÃo de plantas de meloeiro aumenta a tolerÃncia das mesmas ao estresse salino. O experimento foi conduzido no Campo Experimental de Pacajus da Embrapa AgroindÃstria Tropical. Os tratamentos foram dispostos em esquema fatorial 5 x 3 com quatro repetiÃÃes, referentes Ãs soluÃÃes salinas com condutividades elÃtricas de (CEa) (0,5; 1,5; 3,0; 4,5 e 6,0 dS m-1) e trÃs tratamentos de CO2: ausÃncia de CO2 (SC), cinco aplicaÃÃes de CO2 (inÃcio do florescimento atà a maturaÃÃo dos frutos) (C1) e duas aplicaÃÃes de CO2 (apÃs a frutificaÃÃo atà a maturaÃÃo dos frutos) (C2). O CO2 foi aplicado na forma de gÃs, injetado semanalmente diretamente no sistema de irrigaÃÃo. A condutividade elÃtrica do extrato de saturaÃÃo do solo e o teor de CO2 na Ãgua de irrigaÃÃo foram mensurados ao final do experimento. As mediÃÃes de fotossÃntese, transpiraÃÃo e condutÃncia estomÃtica ocorreram ao longo do desenvolvimento das plantas. Foram avaliadas ainda a Ãrea foliar, as massas secas das folhas e do caule + ramos, os teores de Na+, Cl-, K+ e os carboidratos nas folhas e nos caules + ramos, o nÃmero de frutos, a produtividade de frutos, o peso, os comprimentos e diÃmetros dos frutos, espessura da polpa, sÃlidos solÃveis totais e teor de Ãcido cÃtrico. Os teores de Na+, Cl- e k+ na folha e caule + ramos foram influenciados pela salinidade, havendo interaÃÃo salinidade x CO2. Para as variÃveis de crescimento: Ãrea foliar, matÃria seca das folhas e caule +ramos, houve diferenÃa significativa apenas para os nÃveis de salinidade. Todas as variÃveis de trocas gasosas foram influenciadas pela salinidade, enquanto que a condutÃncia estomÃtica e a fotossÃntese liquida foram significativamente influenciadas pela aplicaÃÃo de CO2. Os teores de carboidratos no caule + ramos foram influenciados pela aplicaÃÃo de CO2. A irrigaÃÃo com Ãgua salina provocou reduÃÃo na produtividade, nÃmero de frutos, comprimentos dos frutos comercias e mÃdios. Essas variÃveis nÃo foram influenciadas pela aplicaÃÃo de CO2. Em funÃÃo do exposto, conclui-se que a salinidade afetou o crescimento, desenvolvimento e produÃÃo das plantas de meloeiro, enquanto a aplicaÃÃo do CO2 nÃo minimizou o efeito deletÃrio dos sais nas plantas.

O Brasil produz cerca de 340 mil toneladas de óleo-de-palma. A maior parte provém do território paraense que representa cerca de 90% da produção nacional de óleo-de-palma, com 160 mil hectares plantados em função da aptidão edafoclimática da região que possui condições favoráveis para o desenvolvimento da cultura. Diante da relevância desta cultura, os estudos aqui realizados foram conduzidos com o objetivo de fornecer informações sobre os aspectos fisiológicos, quantificação de biomassa, estoque de carbono e balanço nutricional em plantios de palma-de-óleo com 3, 4, 5, 6 e 7 anos de idade. As investigações aqui relatadas são divididas em quatro capítulos. No primeiro capítulo o objetivo foi estudar as respostas das trocas gasosas em plantações de palma-de-óleo das variedades Deli x Ghana e Compacta x Ghana com 6 e 7 anos de idade, nas condições edafoclimáticas do município de Mojú – PA. O segundo capitulo consiste na quantificada a biomassa das plantas de palma-de-óleo pelo método destrutivo bem como a obtenção de variáveis biométricas de fácil mensuração para o ajuste de equações alométricas específicas e regionais para estimar a biomassa aérea das plantas. A vantagem do desenvolvimento dessa ferramenta (equação) é a economia de tempo, energia e recursos. Pois nas próximas estimativas de biomassa não se faz necessária amostragem destrutiva das plantas. Com a obtenção da biomassa seca da palma-de-óleo o terceiro capitulo foi verificado o potencial da cultura na fixação de carbono em sua biomassa, como quantificar o estoque de carbono no sistema planta, solo e serapilheira. Por fim, o quarto capítulo verificou o conteúdo de nutrientes no solo, na serapilheira e na planta em diferentes compartimentos, finalizando com o balanço de macronutrientes no sistema solo-planta, em plantios de palma-de-óleo, com 3 a 7 anos de idade. No estudo das respostas das trocas gasosas, as plantas de palma-de-óleo com seis anos de idade, apresentaram maiores valores para a condutância estomática, transpiração e a eficiência instantânea da carboxilação (EiC) em relação as plantas com 7 anos de idade para as variedades Deli x Ghana e Compacta x Ghana. Nas condições edafoclimáticas da região, a variedade Compacta x Ghana, somado às suas características genéticas, apresentou maior capacidade de realizar fotossíntese quando comparado a variedade Deli x Ghana. Ficou evidenciado que é possível expressar a biomassa seca total da espécie (Elaeis guineensis Jacq.), com 3 a 7 anos de idade por meio de equações de regressão, utilizando variáveis independentes de fácil obtenção. A concentração de carbono (C) na biomassa das plantas foi de 55,2%, apresentando um estoque de carbono total no sistema (solo+serapilheira+ planta) de 71,16 Mg C ha-1 em plantios com até 7 anos de idade. E finalizando o estudo com balanço de macronutrientes no sistema, onde os plantios de palma-de-óleo apresentaram um balanço positivo para todos os elementos, exceto para o potássio que apresentou saldo negativo nos plantios com 6 e 7 anos de idade. Pode-se afirmar que o manejo realizado nos plantios de palma-de-óleo em Mojú-PA, não exaurem o solo.<br>Brazil produces about 340 thousand tons of palm oil. Most of them come from the territory of Para, which accounts for about 90% of the national palm oil production, with 160,000 hectares planted according to the soil and climate of the region, which has favorable conditions for the development of the crop. Considering the relevance of this culture, the studies carried out were conducted with the objective of providing information on the physiological aspects, quantification of biomass, carbon stock and nutritional balance in oil palm plantations with 3, 4, 5, 6 and 7 years old. The investigations reported here are divided into four chapters. In the first chapter the objective was to study the gas exchange responses in oil palm plantations of the Deli x Ghana and Compacta x Ghana varieties at 6 and 7 years of age, under the edaphoclimatic conditions of the municipality of Mojú - PA. The second chapter consists of quantifying the biomass of the oil palm plants by the destructive method as well as the obtaining of easy-to-measure biometric variables for the adjustment of specific allometric and regional equations to estimate the aerial biomass of the plants. The advantage of developing this tool (equation) is the saving of time, energy and resources. For the next estimates of biomass do not require destructive sampling of plants. With the obtaining of the dry biomass of the oil palm the third chapter was verified the potential of the culture in the fixation of carbon in its biomass, how to quantify the carbon stock in the plant system, soil and litter. Finally, the fourth chapter verified the nutrient content in soil, litter and plant in different compartments, ending with the macronutrient balance in the soil-plant system, in palm oil plantations, from 3 to 7 years of age. In the study of gas exchange responses, six-year-old oil palm plants presented higher values for stomatal conductance, transpiration and instantaneous carboxylation efficiency (EiC) compared to 7-year-old plants for the varieties Deli x Ghana and Compacta x Ghana. In the edaphoclimatic conditions of the region, the Compacta x Ghana variety, added to its genetic characteristics, showed a greater capacity to perform photosynthesis when compared to the Deli x Ghana variety. It was evidenced that it is possible to express the total dry biomass of the species (Elaeis guineensis Jacq.), With 3 to 7 years of age by means of regression equations, using independent variables easily obtainable. The concentration of carbon (C) in plant biomass was 55.2%, presenting a total carbon stock in the system (soil + litter + plant) of 71.16 Mg C ha-1 in plantations up to 7 years of age. At the end of the study with a macronutrient balance in the system, where the oil palm plantations presented a positive balance for all the elements, except for the potassium that presented negative balance in the plantations with 6 and 7 years of age. It can be affirmed that the management carried out in the palm-oil plantations in Mojú-PA, does not exhaust the soil.

Submitted by Jordan (jordanbiblio@gmail.com) on 2017-05-05T13:55:14Z No. of bitstreams: 1 DISS_2015_Magdiel Josias do Prado.pdf: 1377746 bytes, checksum: c0558030ad829d4b3388055267457759 (MD5)<br>Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-05-18T16:23:32Z (GMT) No. of bitstreams: 1 DISS_2015_Magdiel Josias do Prado.pdf: 1377746 bytes, checksum: c0558030ad829d4b3388055267457759 (MD5)<br>Made available in DSpace on 2017-05-18T16:23:32Z (GMT). No. of bitstreams: 1 DISS_2015_Magdiel Josias do Prado.pdf: 1377746 bytes, checksum: c0558030ad829d4b3388055267457759 (MD5) Previous issue date: 2015-02-23<br>CNPq<br>O Pantanal norte de Mato Grosso é caracterizado por quatro períodos sazonais: a enchente, a cheia, a vazante e a seca. Esses períodos determinam uma intensa variação na disponibilidade de água e no grau de oxigenação do solo da região, agindo como um filtro seletivo que permite que somente as espécies com capacidade de adaptação consigam ali sobreviver. Considerando esses aspectos, o objetivo com esta pesquisa foi o de analisar a capacidade adaptativa de duas espécies do gênero Combretum, o C. lanceolatum Pohl ex Eickl e o C. laxum Jacq, que figuram como espécies invasoras na região. Dois aspectos fisiológicos foram levados em consideração para tal avaliação, o intercâmbio gasoso e as relações hídricas. Para ambos os aspectos analisados foram medidas as variáveis inerentes em cada um dos quatro períodos sazonais. Para as medições de intercâmbio gasoso foi utilizado um analisador de gás infravermelho portátil, modelo LI-6400 (LI-COR, Inc., Lincoln, NE, USA) e para análise das relações hídricas foi utilizado uma bomba de pressão do tipo Scholander. Observou-se que a sazonalidade climática, afetou de forma particular o intercambio gasoso das espécies em estudo. Apesar de ambas as espécies ocorrerem de forma extensiva no Pantanal, o que por si é um indicador da adaptabilidade das mesmas ao local, as estratégias fisiológicas adotadas pelas mesmas são diferentes. Do ponto de vista da assimilação do carbono, enquanto o período de vazante causa redução na taxa fotossintética de C. lanceolatum, é o período seco que causa esse mesmo efeito no C. laxum. Enquanto a redução na taxa fotossintética líquida no C. laxum pode estar associada a um efeito estomático, porque nesse período, independentemente das espécies, é quando se verifica o menor valor da condutância estomática; para o C. lanceolatum a redução deve estar mais relacionada com aspectos não estomáticos. Nas relações hídricas observou-se que a capacidade de ressaturação de ambas as espécies variou com a sazonalidade, sendo mais efetivos durante os períodos de enchente e cheia e menos efetivos durante a vazante e a seca. Ambas as espécies não apresentaram variações significativas do conteúdo relativo de água a plena turgência e do módulo volumétrico de elasticidade da parede celular. As variações no potencial osmótico à turgescência plena e à turgescência insipiente não revelam claramente a busca por um ajuste sazonal dessas variáveis. Aparentemente a relativa constância dos valores das variáveis das relações hídricas verificada para ambas as espécies ao longo dos períodos sazonais sugere uma adaptação à qualquer variação extrema na disponibilidade de água no ambiente.<br>The North Pantanal of Mato Grosso is characterized by four seasonal periods: the flood, full, the ebb and dry. These periods determine an intense variation in water availability and the degree of oxygenation of the soil of the region, acting as a selective filter that allows only the species with adaptability able to survive there. Considering these aspects, the aim of this study was to analyze the adaptive capacity of two species of the genus Combretum, C. lanceolatum Pohl ex Eickl and C. laxum Jacq, listed as invasive species in the region. Two physiological aspects were taken into account in this assessment, the gas exchange and water relations. For both aspects analyzed were measured variables inherent in each of the four seasonal periods. For gas exchange, measurement was performed using a portable infrared gas analyzer, Model LI-6400 (Li-COR Inc., Lincoln, NE, USA) and water relations analysis was used a pressure type pump Scholander. It was observed that the seasonality, affected in a particular way the gas exchange of the species studied. Although both species occur extensively in the Pantanal, which in itself is an indicator of the adaptability of the same location, the physiological strategies adopted by them are different. Carbon assimilation of view, while the ebb period causes a reduction in photosynthetic rate of C. lanceolatum, is the dry season, which causes the same effect on C. laxum. While the reduction in net photosynthetic rate in C. laxum may be associated with a stomatal effect because this period, regardless of species, when there is the lowest value of stomatal conductance; for C. lanceolatum the reduction must be more related to aspects not stomatal. In water relations noted that the resaturation capacity of both species with varied seasonally, being more effective during flood periods and full and less effective during ebb tide and dried. Both species showed no significant changes in relative water content at full turgor and bulk modulus of elasticity of the cell wall. Changes in osmotic potential at full turgor and swelling incipient not clearly reveal the search for a seasonal adjustment of these variables. Apparently, the relative constancy of variable water relations values observed for both species along seasonal periods suggests an adaptation to any extreme variation in water availability in the environment.

The saltbush is an C4 species extremely tolerant to soils and saline waters and has good capacity to accumulate quantities of salts in their tissues, also serving as forage potential. Therefore, it is an excellent material for the identification of physiological and biochemical mechanisms involved in the resistance to salinity. The objective of this study was to evaluate the ecophysiological and biochemical responses of saltbush under increasing levels of NaCl. Plants were grown in pots kept in a greenhouse and irrigated every 2 days at concentrations of 0, 150, 300, 450 and 600 mM NaCl over time. Were determined biometric (height and stem diameter), gas exchange (photosynthetic assimilation of CO2 (A), stomatal conductance (gS), the internal concentration of carbon (Ci), transpiration (E) and vapor pressure deficit between leaf and air (DPVair-leaf)), the content of chlorophyll (Chl a, Chl b, Chl total and Chl a / b) and content of proline in leaves. The experimental design was completely randomized in a 5x4 factorial scheme, with five levels of salinity and for evaluation periods (0, 15, 30 and 45 days) with 5 replications. At 60 days evaluated the effect of levels 0, 150 and 300 mM NaCl on growth, fresh and dry biomass of shoot (stem+leaves) and root, gas exchange, content of chlorophyll, content of Na+, K+ and Na+/K+ in shoot and roots, and content of proline in leaves. The experimental design was DIC, with three levels of salinity and five replications. Until 45 days saltbush presented a stimulating growth at all levels of NaCl, and 0, 150 and 300 mM NaCl showed the highest values of height and stem diameter. As for the gas exchange saltbush presented an adaptive period of 15 days, followed by increase in photosynthetic assimilation. The saltbush accumulated more Na+ than K+, with greater accumulation in the shoot than in the root, to the 300 mM NaCl level, this is the salinity level that the highest yield of fresh biomass (46,38 g) and dried (19,69 g). Increased salinity promoted accumulation of proline, whose highest concentration (3,11 micromol g-1 FM) was observed in 600 mM NaCl treatment. At 60 days the salt stress induced no significant differences in plant growth, but promoted reduction of photosynthetic assimilation and increased internal carbon concentration. After 60 days, saltbush accumulated Na+ in shoot with growth and biomass production was enhanced up to 300 mM NaCl level. Increased levels of salinity reduces the photosynthetic assimilation of the saltbush, but did not significantly affect the production of chlorophylls. In response to salinity saltbush has increased the concentration of proline in their leaves. With increasing salinity, the saltbush develops physiological and biochemical mechanisms to ensure its growth, with the 300 mM NaCl level which favors its maximum production.<br>A erva-sal e uma especie C4 extremamente tolerante aos solos e as aguas salinas e possui boa capacidade de acumular quantidades de sais em seus tecidos, servindo tambem como potencial forrageiro. Portanto, e um excelente material para a identificacao de mecanismos fisiologicos e bioquimicos envolvidos na resistencia a salinidade. O objetivo deste trabalho foi avaliar as respostas ecofisiologicas e bioquimicas da erva-sal sob niveis crescentes de NaCl. As plantas foram cultivadas em vasos mantidos em casa de vegetacao e irrigadas a cada 2 dias nas concentracoes 0, 150, 300, 450 e 600 mM de NaCl ao longo do tempo. Foram determinados a biometria (altura e diametro do caule), trocas gasosas (assimilacao fotossintetica de CO2 (A), condutancia estomatica (gS), concentracao interna de carbono (Ci), transpiracao (E) e deficit de pressao de vapor entre o ar e a folha (DPVfolha-ar)), teor relativo de clorofilas (Chl a, Chl b, Chl total e relacao Chl a/b) e teor de prolina nas folhas. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 5x4, sendo cinco niveis de salinidade e quatro periodos de avaliacao (0, 15, 30 e 45 dias), com 5 repeticoes. Aos 60 dias avaliou-se o efeito dos niveis 0, 150 e 300 mM de NaCl no crescimento, biomassa fresca e seca da parte aerea (caule+folhas) e raiz, trocas gasosas, teor relativo de clorofilas, teor de Na+, K+ e relacao Na+/K+ na parte aerea e raiz, e teor de prolina nas folhas. O delineamento experimental foi DIC, sendo tres niveis de salinidade e cinco repeticoes. Ate os 45 dias a erva-sal apresentou um estimulo do crescimento em todos os niveis de NaCl, sendo 0, 150 e 300 mM de NaCl os que apresentaram maiores valores de altura e diametro do caule. Quanto as trocas gasosas a erva-sal apresentou um periodo adaptativo de 15 dias, seguido de incremento da assimilacao fotossintetica. A erva-sal acumulou mais Na+ que K+, com maior acumulo na parte aerea que na raiz, ate o nivel 300 mM de NaCl, sendo este o nivel de salinidade que proporcionou maior producao de biomassa fresca (46,38 g) e seca (19,69 g) . O aumento da salinidade promoveu acumulo de prolina, cuja maior concentracao (3,11 Êmol g-1 MF) foi verificado no tratamento 600 mM de NaCl. Aos 60 dias o estresse salino nao induziu diferencas significativas no crescimento das plantas, mas promoveu reducao da assimilacao fotossintetica e aumento da concentracao interna de carbono. Apos 60 dias, a erva-sal acumulou Na+ em sua parte aerea, com crescimento e producao de biomassa favorecidas ate o nivel 300 mM de NaCl. O aumento nos niveis de salinidade reduz a assimilacao fotossintetica da erva-sal, mas nao afetou significativamente a producao de clorofilas. Em resposta a salinidade a erva-sal apresenta aumento na concentracao de prolina em suas folhas. Sob salinidade crescente, a erva-sal desenvolve mecanismos fisiologicos e bioquimicos capazes de assegurar seu crescimento, sendo o nivel 300 mM de NaCl o que favorece seu maximo de producao.

Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-29T14:02:49Z No. of bitstreams: 1 FRANCISCO ALVES DA SILVA - DISSERTAÇÃO PPGSA PROFISSIONAL 2017..pdf: 1819425 bytes, checksum: 4b220cab9b149dc8926955eef14030cc (MD5)<br>Made available in DSpace on 2018-05-29T14:02:49Z (GMT). No. of bitstreams: 1 FRANCISCO ALVES DA SILVA - DISSERTAÇÃO PPGSA PROFISSIONAL 2017..pdf: 1819425 bytes, checksum: 4b220cab9b149dc8926955eef14030cc (MD5) Previous issue date: 2017-08<br>A região semiárida é caracterizada por irregularidade das chuvas e baixo índice pluviométrico, que limita o desenvolvimento da agricultura em condições de sequeiro, remetendo a necessidade do uso sustentável da irrigação, sendo necessário, o uso de espécies com potencial econômico, a exemplo dos citros, e que possam ser cultivadas com menor uso de recursos hídricos, tornando a agricultura mais eficiente. Neste sentido, a identificação de genótipos com maior tolerância ao estresse hídrico torna-se essencial para atender esta demanda. Assim, objetivou-se estudar o crescimento, fisiológicos e adaptabilidade ao estresse hídrico de combinações copa/porta-enxertos de citros durante a prefloração sob lâminas de irrigação no semiárido paraibano. O experimento foi realizado no período de agosto de 2016 a abril de 2017, correspondendo a 270 dias, na Fazenda experimental do Centro de Ciências e Tecnologia Agroalimentar da niversidade Federal de Campina Grande, em São Domingos -PB. No delineamento experimental de blocos casualizados, foram estudadas 11 combinações copa/portaenxerto sob lâminas de irrigação, perfazendo um esquema fatorial (11x2), com 3 repetições, totalizando 66 parcelas experimentais compostas por uma planta útil, cada. As combinações copa/porta-enxerto foram relativas à combinação de genótipos de porta-enxertos: 1. LIMOEIRO CRAVO COMUM (LCR); 2. Tangerineira Sunki Comum (TSKC) x [LCR x Poncirus trifoliata TR] – 01; 3. TSKC x (LCR x TR) – 018; 4. TSKC x (LCR x TR) – 20; 5. TSKC x (LCR x TR) – 029; 6. TSKC x Citrumelo Swingle CTSW – 022; 7. Tangerina Sunki da Flórida TSKFL x (LCR x TR) – 038; 8. TSKFL x (LCR x TR) – 044; 9. TSKFL x (LCR x TR) – 049; 10. TSKFL x (TCR x TR) – 062 e 11. TSKFL x (LCR x TR) – 069, enxertados com a limeira ácida „Tahiti‟. Tais combinações foram submetidas a duas lâminas de água, correspondentes a 50 e 100% da evapotranspiração de referência (ETo). Avaliaram-se, bimestralmente, iniciando-se 15 dias após o transplantio (DAT), variáveis fisiológicas e o crescimento das plantas durante a prefloração. xii Os genótipos enxertados na limeira ácida „Tahiti‟ podem ser cultivados no semiárido da Paraíba, mesmo sob baixo sob lâminas de irrigação de 50% da evapotranspiração de referência diária durante o crescimento da prefloração, em virtude da manutenção da atividade fisiológica das plantas e não ocorrência de dano ao aparato fotossintético; A avaliação de trocas gasosas permite diferenciar genótipos resistente e suscetível ao estresse hídrico; Os híbridos de tangerineira Sunki da Flórida (TSKFL), quando enxertados com a limeira ácida „Tahiti‟, mantêm menor status hídrico e proporcionam, à variedade copa, maior crescimento, mesmo sob menor lâmina de irrigação; as combinações menos sensíveis a déficit hídrico foram compostas pelo „Tahiti‟ enxertado com o TSKFL x (LCR x TR) – 049, TSKFL x (LCR x TR) – 062, TSKFL x (LCR x TR) – 69.<br>The low annual rainfall and irregularity of seasons in semi-arid regions hamper the development of rainfed agriculture, which leads to the need of sustainable irrigation systems. Plants with little demand for water, such as the citrus ones, enhances the efficiency of agriculture. The identification of genotypes with high tolerance to water stress becomes essential to meet this demand. In this study, we investigated the growth, physiology, and adaptability to water stress of pre-flowering citrus plants at different combinations of canopy/rootstocks under different irrigation depths in the semi-arid region of Paraiba. The experiment was carried out during 270 days, from August 2016 to April 2017, at the Experimental Farm of the Center for Agrifood Science and Technology of the Federal University of Campina Grande, São Domingos, Paraíba, Brazil. We applied a randomized block design, with eleven canopy/rootstock combinations and two irrigation depths, each treatment had three replicates, totaling 66 experimental units. The following genotypes of rootstock were grafted with the „Tahiti‟ acid lime: 1. Rangpur (LCR); 2. Common Sunki Mandarin (TSKC) x [LCR x Poncirus trifoliata TR] – 01; 3. TSKC x (LCR x TR) – 018; 4. TSKC x (LCR x TR) – 020; 5. TSKC x (LCR x TR) – 029; 6. TSKC x Citrumelo Swingle CTSW – 022; 7. Florida Sunki Mandarin TSKFL x (LCR x TR) – 038; 8. TSKFL x (LCR x TR) – 044; 9. TSKFL x (LCR x TR) – 049; 10. TSKFL x (TCR x TR) – 062; and 11. TSKFL x (LCR x TR) – 069. These combinations were submitted to two irrigation depths, 50 and 100% of the reference evapotranspiration (ETo). After 15 days from the transplanting (DAT), we started to measure, bimonthly, the physiological variables and plant growth during the pre-flowering period. The genotypes grafted on the 'Tahiti' acid lime tree can be grown in the Paraíba semi-arid, even under low under irrigation mounth of 50% from the daily reference evapotranspiration during prefloration stage, due to the maintenance of the physiological activity of the plants and non-occurrence damage to the photosynthetic apparatus; the evaluation of gas exchange allows to differentiate genotypes resistant and susceptible to xiv water stress; hybrids from Florida Sunki mandarin (TSKFL), when grafted with the 'Tahiti' acid lime tree, maintain lower water status and provide the canopy variety a greater growth, even under a lower irrigation mounth and the combinations less sensitive to water deficit were composed of Tahiti grafted with TSKFL x (LCR x TR) - 049, TSKFL x (LCR x TR) - 062, TSKFL x (LCR x TR) - 69.

Дисертацію присвячено екологічній проблемі зменшення впливу компресорних станцій магістральних газопроводів на навколишнє середовище шляхом розробки енергозберігаючого та екологічнобезпечного обладнання і систем. Проведений аналіз досліджень екологічної небезпеки компресорних станцій та результатів вивчення-процесів формування ареалів забруднення атмосфери. Запропонована і обгрунтована нова концепція повітряного опалення приміщень різної категорії по вибухопожежобезпечності від одного джерела теплого повітря. Створено методику розрахунку та проектування енергозберігаючих, екологічнобезпечних систем повітряного опалення будівель компресорних цехів, індивідуальних укриттів для електроприводних або газотурбінних газоперекачуючих агрегатів. Розроблено та досліджено у лабораторних умовах простий, надійний іскрогасник для електродвигуна. Запропоновані, досліджені за допомогою математичної моделі, що розроблена, ефективні утилізаційні теплообмінники для імпортних газоперекачуючих агрегатів. Результати досліджень основних характеристик теплообмінників для імпортних та вітчизняних агрегатів узагальнені у вигляді аналітичних залежностей, що дозволяють врахувати умови експлуатації обладнання.<br>Диссертация посвящена экологической проблеме уменьшения влияния компрессорных станций магистральных газопроводов на окружающую среду, путём разработки методических основ проектирования, создания энергосберегающего, экологически безопасного оборудования и систем. Проведен анализ отечественного теплоутилизационного оборудования, систем воздушного и водяного отопления зданий, индивидуальных укрытий электроприводных и газотурбинных газоперекачивающих агрегатов. Результаты исследований основных характеристик теплообменников для импортных и отечественных агрегатов обобщены в виде удобных для практического использования аналитических зависимостей, позволяющих учитывать условия эксплуатации оборудования на компрессорных станциях газопроводов.<br>The dissertation is devoted to development of methodical basis of design, creation and research energy saving, ecologicaly safe equipment and systems for compressor stations of trunk gas pipelines. There offered and grounded nem conception of air heating for premises of different categories of fire-explosion dangerosity from single source of warm air. There created the method of calculation and energy saving, ecologicfly safe systems of air heating for buildings of compressor workshops, individual shelters of gas turbine and electric gas pumping plants. There was designed and researched in lab-conditions a simple and reliable spark-suppression device lor electrical engine. There, offered, researched with the help of designed mathematical model and inculcated the efficient utilizing heat exchanger for foreign gas-pumping plants. The research results of main characteristics of heat exchanges for foreign and home-produced plants were generalized and submitted as useful for practical exploitation analytical equations. Which allow considering the conditions of equipment exploitation.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico<br>No cultivo de plantas medicinais as condiÃÃes de salinidade e de luz podem exercer influÃncia no rendimento e qualidade final da produÃÃo de fitomassa. Este trabalho foi desenvolvido no NÃcleo de Ensino e Pesquisa em Agricultura Urbana (NEPAU) da Universidade Federal do Cearà â UFC, em Fortaleza â CE, com o objetivo de avaliar o efeito de diferentes nÃveis luminosidades e de salinidade na Ãgua de irrigaÃÃo no crescimento e respostas fisiolÃgicas de trÃs espÃcies medicinais do gÃnero Plectranthus. Utilizou-se o delineamento experimental em parcelas subsubdivididas, com cinco repetiÃÃes, sendo as parcelas referentes ao fator ambiente (pleno sol e telado), as subparcelas referentes aos nÃveis de salinidade na Ãgua de irrigaÃÃo - CEa (0,7; 1,9; 3,1; 4,3 e 5,5 dS m-1), e as subsubparcelas Ãs trÃs espÃcies do gÃnero Plectranthus (P. amboinicus, P. barbatus e P. grandis). O experimento teve a duraÃÃo de 60 dias, apÃs o transplantio, sendo realizadas as seguintes avaliaÃÃes: Ãrea foliar, produÃÃo massa seca da parte aÃrea, massa seca das raÃzes, trocas gasosas, teores de clorofila e acÃmulo de solutos orgÃnicos e inorgÃnicos. O estresse salino induziu reduÃÃes significativas no crescimento e nas trocas gasosas das trÃs espÃcies avaliadas, com as maiores reduÃÃes sendo verificadas nas plantas expostas a pleno sol. A resposta à salinidade da espÃcie P. grandis foi menos influenciada pelo ambiente de cultivo do que nas duas outras espÃcies estudadas. A salinidade afetou a partiÃÃo de matÃria seca, sendo as raÃzes mais afetadas do que a parte aÃrea. Em relaÃÃo a produÃÃo de matÃria seca total, verifica-se que as trÃs espÃcies estudadas se mostraram tolerantes ou moderadamente tolerantes à salinidade de atà 3,1 dS m-1, porÃm na salinidade de 5,5 dS m-1 todas se mostraram sensÃveis ao excesso de sais na Ãgua de irrigaÃÃo. Considerando-se o grau de reduÃÃo na produÃÃo de massa seca da parte aÃrea (parte de interesse comercial), poderia-se recomendar o cultivo da espÃcie P. grandis quando se dispÃe de Ãgua de irrigaÃÃo com CEa de atà 3,1 dS m-1. Verificou-se aumento expressivo na acumulaÃÃo de Na+ e Cl-, e reduÃÃes no teor de potÃssio, tanto nas hastes quanto nas folhas. Em decorrÃncia do maior acÃmulo de sÃdio nas hastes, a relaÃÃo dos Ãons Na+/K+ nesta parte da planta atingiu valor de 1,6 na CEa de 5,5 dS m-1, indicando um possÃvel desequilÃbrio nutricional e toxicidade de Ãons. Para os solutos orgÃnicos, o teor de carboidratos nÃo foi alterado com o aumento da CEa, porÃm os teores de prolina e N-aminossolÃveis aumentaram em resposta ao estresse, sendo que no caso da prolina os aumentos foram maiores na espÃcie P. grandis cultivada em pleno sol.<br>Growing medicinal plants in the conditions of salinity and light can exert influence on yield and final quality of the biomass production. This work was developed at the Center for Teaching and Research in Urban Agriculture (NEPAU), Federal University of Cearà - UFC, Fortaleza - CE, with the objective of evaluating the effect of different luminosities and salinity levels in irrigation water on growth and physiological responses of three medicinal species of the genus Plectranthus. It was used the completely randomized split plots with five repetitions, the plots had corresponded to the environmental factor (mesh with 50% luminosity and full sunlight) and the split plots for five levels of salt stress in irrigation water â CEw (0.7, 1.9, 3.1, 4.3 and 5.5 dS m-1 ) and the subsubplots the medicinal species (P. amboinicus, P. barbatus and P. grandis). The experiment lasted for 60 days after transplanting, being determined by the following: leaf area, dry mass production of shoot, root dry mass, gas exchange, chlorophyll content and accumulation of organic and inorganic solutes. Salt stress induced significant reductions in the growth and gas exchange of the three species evaluated, with the largest reductions being observed in plants exposed to full sunlight. The response to the salinity of the species P. grandis was less influenced by growth environment than in the other two species. Salinity affected the dry matter partitioning, the roots being more affected than the shoot. Considering the total dry matter production, it is found that all three species studied were moderately tolerant or salinity tolerance of up to 3.1 dS m-1 but on the salinity of 5.5 dS m-1 all were sensitive to excess salts in the irrigation water. Considering the degree of reduction in the production of raw party area (part of commercial interest), one could recommend the cultivation of the species P. grandis when it has irrigation water with ECw up to 3.1 dS m-1 . There was significant increase in the accumulation of Na+ and Cl- , and reductions in potassium content, both on the stems as the leaves. Due to the higher accumulation of sodium in the stems, the ratio of Na+ /K+ in this part of the plant reached a value of 1.5 in CEa of 5.5 dS m-1 , indicating a possible nutritional imbalance and ion toxicity. For the organic solutes, the carbohydrate content was not changed with increasing salinity but the concentrations of proline and N-aminosoluble increased in response to stress and in the case of proline elevations were higher in the species P. grandis grown in full sunlight.

L'arsenic et l'antimoine bien que n'étant pas recensés parmi les polluants majeurs de l'environnement sont souvent retrouvés associés à d'autres contaminants. En France, et plus particulièrement dans la région Auvergne, de nombreux sites miniers où s'effectuait l'extraction de l'antimoine sont désormais à l'abandon. Pouvant présenter des risques pour les populations avoisinantes, leur réhabilitation est donc une mission d'intérêt public. L'idée de ce travail de doctorat est de tester l'effet d'un catalyseur : le ver de terre sur l'efficacité des processus de phytoremédiation. En tant qu'" ingénieurs du sol ", ils sont à la base des processus de pédogénèse et peuvent donc assurer la restructuration du sol. De plus, de nombreuses études ont montré leurs effets positifs sur la production de biomasse végétale. Cependant, les mécanismes moléculaires responsables de cette acroissement de production demeurent méconnus. Un système expérimental novateur, jamais utilisé en Ecologie des Sols et couplant la plante modèle Arabidopsis thaliana (L.) Heynh et Aporrectodea caliginosa (Savigny), un ver de terre endogé commun des régions tempérées, a été mis en place afin de 1) identifier les principales voies métaboliques modifiées en réponse aux vers de terre et pouvant expliquer leurs effets positifs sur la croissance et le développement des végétaux, 2) étudier la nutrition minérale en fer et en phosphate, notamment au niveau des variations d'expression des transporteurs de ces deux éléments, 3) tester ce système pour la phytoextraction de sédiments, issus d'un ancien site minier, contaminés à l'arsenic et à l'antimoine. Les résultats montrent que l'amélioration des processus de minéralisation est déterminante dans l'accroissement de la biomasse d'Arabidopsis thaliana qui se traduit aussi par une élévation des teneurs en azote dans les parties aériennes. Cependant, la présence de phytohormones, produites par des bactéries activées par leur transit dans le ver de terre semble également impliquée dans le renforcement de l'absorption d'azote. A l'échelle moléculaire, les vers entraînent une surexpression du gène HBT, impliqué dans la division cellulaire et semblent diminuer le stress oxydant puisque la quantité de transcrits SOD Cu/Zn diminue. Les résultats montrent de plus que les vers de terre augmentent de façon significative l'absorption et l'accumulation de fer, de phosphate et d'autres minéraux essentiels à la croissance du végétal. Moléculairement, l'augmentation de l'absorption des nutriments se traduit par une augmentation de la transcription de certains gènes codant des transporteurs tels que PHT1.3, qui est un transporteur de haute affinité pour le phosphate. Une augmentation de la transcription et également de l'activité de la protéine FRO2, qui est à l'origine de la chélation et de la réduction du fer a été observée. Dans les feuilles, les vers de terre induisent de manière systémique la surexpression d'un transporteur de phosphate localisé dans les chloroplastes, PHT2.1 et la surexpression de transporteurs du fer appartenant à la famille des NRAMPs, notamment NRAMP1,2 et 6. Dans le contexte d'une problématique de phytoremédiation, l'effet des vers de terre sur la capacité de phytoextraction d'Arabidopsis a été testé et, il ressort clairement de cette étude que les vers de terre permettent une meilleure absorption d'antimoine et d'arsenic. Cependant, ces deux métalloïdes tendent à rester dans les racines et ne sont que faiblement transferrés vers les parties aériennes. Cette formidable augmentation des concentrations en polluants dans les racines entraîne un retard de croissance considérable et affecte, dans une moindre mesure cependant, l'activité photosynthétique et les échanges gazeux d'Arabidopsis. Ainsi, ce travail de thèse a donc tout d'abord démontré la sensibilité aux vers de terre de la plante modèle Arabidopsis thaliana. Ce système expérimental novateur offre de nouvelles possibilités de recherches dans le domaine des études des interactions entre les vers de terre et les plantes, notamment en raison de la grande diversité de mutants d'Arabidopsis. De plus, ce travail a également permis de démontrer le rôle crucial de catalyseur que peuvent jouer les vers de terre en vue d'optimisation des processus de phytoextraction

This diploma’s thesis analyzes the possibility of accumulation of thermal power plants in the Czech Republic. The thesis is divided into several parts. The first part describes the different types of storage power plants, the historical development of power storage for compressed air and the appropriateness of their location. The second part is devoted to the design of storage power plant for compressed air in South Moravia. In the next chapter, a calculation is made of all equipment storage power plant, including turbo-compressor, combustion chamber, combustion turbines, the volume of storage tanks and two heat exchangers. The last part is the economic analysis of the return on investment of such a project.

Les challenges posés par les missions d’exploration du système solaire sont très différents de ceux de la Station Spatiale Internationale, puisque les distances sont beaucoup plus importantes, limitant la possibilité de ravitaillements réguliers. Les systèmes support-vie basés sur des plantes supérieures et des micro-organismes, comme le projet de l’Agence Spatiale Européenne (ESA) MELiSSA (Micro Ecological Life Support System Alternative) permettront aux équipages d’être autonomes en termes de production de nourriture, revitalisation de l’air et de recyclage d’eau, tout en fermant les cycles de l’eau, de l’oxygène, de l’azote et du carbone, pendant les missions longue durée, et deviendront donc essentiels.La croissance et le développement des plantes et autres organismes biologiques sont fortement influencés par les conditions environnementales (par exemple la gravité, la pression, la température, l’humidité relative, les pressions partielles en O2 et CO2). Pour prédire la croissance des plantes dans ces conditions non-standard, il est crucial de développer des modèles de croissance mécanistiques, permettant une étude multi-échelle des différents phénomènes, ainsi que d’acquérir une compréhension approfondie de tous les processus impliqués dans le développement des plantes en environnement de gravité réduite et d’identifier les lacunes de connaissance.En particulier, les échanges gazeux à la surface de la feuille sont altérés en gravité réduite, ce qui pourrait diminuer la croissance des plantes dans l’espace. Ainsi, nous avons étudié les relations complexes entre convection forcée, niveau de gravité et production de biomasse et avons trouvé que l’inclusion de la gravité comme paramètre dans les modèles d’échanges gazeux des plantes nécessite une description précise des transferts de matière et d’énergie dans la couche limite. Nous avons ajouté un bilan d’énergie au bilan de masse du modèle de croissance de plante déjà existant et cela a ajouté des variations temporelles sur la température de surface des feuilles.Cette variable peut être mesurée à l’aide de caméras infra-rouges et nous avons réalisé une expérience en vol parabolique et cela nous a permis de valider des modèles de transferts gazeux locaux en 0g et 2g, sans ventilation.Enfin, le transport de sève, la croissance racinaire et la sénescence des feuilles doivent être étudiés en conditions de gravité réduite. Cela permettrait de lier notre modèle d’échanges gazeux à la morphologie des plantes et aux allocations de ressources dans une plante et ainsi arriver à un modèle mécanistique complet de la croissance des plantes en environnement de gravité réduite<br>Challenges triggered by human space exploration of the solar system are different from those of the International Space Station because distances and time frames are of a different scale, preventing frequent resupplies. Bioregenerative life-support systems based on higher plants and microorganisms, such as the ESA Micro-Ecological Life Support System Alternative (MELiSSA) project will enable crews to be autonomous in food production, air revitalization, and water recycling, while closing cycles for water, oxygen, nitrogen, and carbon, during long-duration missions and will thus become necessary.The growth and development of higher plants and other biological organisms are strongly influenced by environmental conditions (e.g. gravity, pressure, temperature, relative humidity, partial pressure of O2 or CO2). To predict plant growth in these non-standard conditions, it is crucial to develop mechanistic models of plant growth, enabling multi-scale study of different phenomena, as well as gaining thorough understanding on all processes involved in plant development in low gravity environment and identifying knowledge gaps.Especially gas exchanges at the leaf surface are altered in reduced gravity, which could reduce plant growth in space. Thus, we studied the intricate relationships between forced convection, gravity levels and biomass production and found that the inclusion of gravity as a parameter in plant gas exchanges models requires accurate mass and heat transfer descriptions in the boundary layer. We introduced an energy coupling to the already existing mass balance model of plant growth and this introduced time-dependent variations of the leaf surface temperature.This variable can be measured using infra-red cameras and we implemented a parabolic flight experiment, which enabled us to validate local gas transfer models in 0g and 2g without ventilation.Finally, sap transport needs to be studied in reduced gravity environments, along with root absorption and leaf senescence. This would enable to link our gas exchanges model to plant morphology and resources allocations, and achieve a complete mechanistic model of plant growth in low gravity environments

La confrontation des cinetiques d'evolution des criteres physico-chimiques permet de mesurer de profonds changements metaboliques a la veraison, a la maturite commerciale et au point de fletrissement. Un modele est propose dans lequel la cerise subit un phenomene de senescence continu au cours duquel se greffent aux 3 stades physiologiques etudies, differentes expressions du genome caracteristiques des etapes classiques associees au vieillissement des fruits