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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Cluster Thinning Effects on Methoxypyrazine, Resveratrol and Berry Chemistry in Vitis vinifera cv. Cabernet Sauvignon

Fertel, Thomas Jerome 01 June 2011 (has links) (PDF)
Cabernet sauvignon is the most widely planted red wine grape in California and is valued in the hundreds of millions of dollars. Cabernet sauvignon grapes, when severely vigorous or overcropped, can contain vegetal aromas and flavors when harvested. 3-alkyl-methoxypyrazines are the volatile compounds responsible for this effect and can lower the perceived quality of the wine. Resveratrol is a phytoalexin that has many medical and health benefits and can be found in red wines. An experiment was conducted in Paso Robles, CA to assess the effects of five yield levels, manipulated through cluster thinning, on methoxypyrazine and resveratrol concentrations. Berry weights and chemistry were also measured, in the form of ºBrix, pH, and TA. In 2009 and 2010, no significant statistical differences were found in methoxypyrazines in the harvested grapes. In 2009, resveratrol concentrations were below the detection limits in the wine produced. In 2010, berry weight and chemistry measurements were not significantly different, except for grapes from lightly- and greatly-thinned vines which varied in pH at harvest. The 2009 wines were subjected to discrimination and preference testing by trained tasters. No significant difference was found in the discrimination test and no difference was found using the Friedman and Kramer’s Rank test for the preference test. Only a very slight difference was found between the wines made from unthinned and greatly-thinned vines according to Tukey’s Multiple Comparison Test. The findings of this thesis suggest that cluster thinning does not affect methoxypyrazine and resveratrol concentrations or sensory analysis in Cabernet sauvignon grown on the east side of Paso Roble, CA.
52

Exploring Phosphoenolpyruvate carboxylase kinase as a potential key regulator of carbon flow towards phenylpropanoid-stilbenoid pathways in grapevine (Vitis vinifera L.)

Hurtado-Gaitán, Elías 26 November 2020 (has links)
Las especies vegetales están continuamente desafiadas por un extenso número de microorganismos patógenos en su ambiente natural, principalmente bacterias, hongos y virus. Las plantas cuentan con un amplio arsenal de mecanismos de defensa tanto constitutivos como inducibles frente a estos patógenos. Los mecanismos inducibles incluyen el estadillo oxidativo, muerte celular rápida y localizada, acumulación de fitoalexinas y la síntesis de proteínas relacionadas con la patogénesis (Proteínas PR). Centrándose en las fitoalexinas, estas son compuestos antimicrobianos de bajo peso molecular producidos por las plantas en respuesta a estrés biótico y abiótico. Las fitoalexinas poseen un amplio rango de propiedades antifúngicas en varias especies de plantas. Debido a esto, estos compuestos han sido objeto de numerosos estudios en los últimos 20 años. En la Vid, Vitis vinífera L., la respuesta mejor caracterizada y más frecuente frente a la infección fúngica es la extensa acumulación de fitoalexinas y de proteínas relacionadas con la patogénesis. Entre la gran diversidad de compuestos naturales bioactivos producidos por las especies de Vitis sp. las fitoalexinas están formadas por un grupo reducido de moléculas que pertenecen a la familia de los estilbenos. Las células de vid son capaces de acumular estilnenos en respuesta a estrés biótico y abiótico. Los estilbenos de la vid derivan primariamente del trans-resveratrol (tR) (3,4`,5 -trihidroxiestilbeno), el cual puede sufrir modificaciones químicas, como glicosilación, metilación, hidroxilación y oligomerización, dando lugar a varios derivados bioactivos. tR es producido como producto final de la ruta fenilpropanoide mediante la condensación de tres moléculas de malonil-CoA con una molécula de 4-cumaroil-CoA en una reacción catalizada por la Estilbeno Sintasa (STS). Los estilbenos de la vid han sido ampliamente estudiados ya que poseen unas propiedades en la salud humana sorprendentes. Se han observado beneficios del tR en las principales enfermedades humanas, como agente cardioprotector, como inhibidor de la carcinogénesis, neuro protector y antienvejecimiento entre otros, ya que tR posee un alto efecto antioxidante. Por lo tanto, el interés farmacéutico, nutracéutico y biotecnológico del tR y por tanto de la vid, han ido en aumento desde los últimos 20 años. De la misma manera, la respuesta de defensa ha sido estudiada en cultivos celulares de vid utilizando inductores naturales de esta respuesta. En este sentido, la 2,6 dimetil-ꞵ-ciclodextrina (MBCD) ha demostrado poseer un gran poder elicitor, promoviendo la producción de tR y su acumulación extracelular. Estos estudios han permitido profundizar en los diferentes mecanismos de regulación de la producción de estos compuestos a través de análisis transcriptómicos y proteómicos. Sin embargo, estos análisis revelaron algunos genes y proteínas cuyo papel en esta respuesta es desconocida hasta hoy. Este es el caso de dos parálogos de Fosfoenolpiruvato carboxilasa quinasa (PPCK). La presente tesis doctoral está centrada en el estudio del posible papel regulador de la enzima fosfoenolpiruvato carboxilasa quinasa (PPCK) en la producción de resveratrol y otros metabolitos secundarios en cultivos celulares de vid. La hipótesis principal de esta tesis es que dicha enzima podría estar regulando el flujo del carbono entre el metabolismo primario y secundario, con la finalidad de potenciar este último en condiciones de estrés. Para demostrar esta hipótesis, el contenido de la tesis se divide en 4 capítulos principales. El primer capítulo consiste en el desarrollo de un método analítico basado en espectrometría de masas de triple cuadrupolo para la detección precisa y la cuantificación exacta de resveratrol y sus derivados bioactivos, producidos por la vid. El segundo capítulo es un estudio transcripcional de 2 isoformas de la enzima PPCK, así como el sustrato de esta última (la enzima fosfoenolpiruvato carboxilsa, PPC), en condiciones de estrés, además de estudiar la coexpression con enzimas y factores de transcripción cuyo papel en la producción de resveratrol se conoce con anterioridad. En este capítulo se demuestra tanto en cultivos celulares de vid, como en hojas intactas, que los genes PPCK son fuertemente reprimidos en condiciones de estrés, mientras que los genes PPC permanecen invariables. En cambio se produce un descenso en torno al 20-30% en la actividad específica de la enzima PPC en tales condiciones. Por otro lado, en tales condiciones se observa la correlación entre la represión de los genes PPCK y el incremento en la producción de resveratrol y otros estilbenos. Es conocido que los cambios de actividad en la enzima PPC son debidos a cambios en la fosforilación de la misma, los cuales a su vez son regulados por la PPCK. Por lo tanto el capítulo 3 consiste en el desarrollo de un método para detectar y cuantificar cambios en el patrón de fosforilación de la enzima PPC, adoptando una estrategia de proteómica dirigida. El desarrollo de esté método para la proteína PPC ha permitido observar como el estrés inducido por MBCD provoca un descenso en el grado de fosforilación de la enzima PPC, lo cual correlaciona directamente con el descenso en su actividad específica, y ambos efectos a su vez están correlacionados con la represión génica de su proteína reguladora PPCK. Por último el capítulo 4 es el análisis funcional de los genes PPCK, a través de transformación genética estable de cultivos celulares de vid, con la finalidad de sobreexpresar los genes PPCK, y del silenciamiento genético de los mismos. Los cultivos celulares transformates que sobreexpresaban alguno de los dos parálogos de PPCK resultaron acumular menos resveratrol en condiciones de estrés en comparación con la estirpe silvestre (WT) avalando de esta manera nuestra hipótesis inicial. Además, este efecto no afectaba únicamente a la producción de resveratrol, si no a una gran variedad de metabolitos secundarios producidos en la ruta fenilpropanoide (Flavonoides, taninos condensados, ácidos hidroxicinámicos etc.) sugiriendo que el papel de la enzima PPCK está implicado en la regulación del suministro de carbono hacia esa vía en condiciones de estrés. Por último, el silenciamiento genético tuvo una eficiencia inadecuada, sugiriendo que los genes PPCK pueden ser esenciales, y difícilmente manipulables por en la región metabólica en la que participan. / La presente tesis doctoral ha sido financiada gracias a la subvención de Ministerio de economía y competitividad (BIO2014-51861-R) y (BIO2017- 82374-R). Así mismo, las dos estancias de investigación realizadas en el Integrative Biology Institute, Liverpool University, (Liverpool) han sido financiadas por la Escuela de Doctorado de la Universidad de Alicante, a través del programa de subvenciones para facilitar la obtención de la mención de Doctorado internacional en el título de Doctor y por la European Molecular Biology Organization (EMBO) a través de su programa Short-term Fellowships (ASTF No 7754).
53

Evaluation of Nitrogen Management Schemes upon Vine Performance in Cover Cropped Vineyards

Moss, James Russell 12 August 2016 (has links)
Vineyards in the Eastern United States are often prone to excessive vegetative growth. In order to suppress excessive vine vigor, many viticulturists have employed cover cropping strategies. Cover crops provide a myriad of agronomic benefits, however they are known to compete with the vine for water and nutrients. Due to the widespread use of cover crops in Eastern vineyards, many vineyards experience nitrogen (N) deficiencies in both the vegetative vine tissue and yeast assimilable nitrogen (YAN) in the juice. Soil applications of calcium nitrate and foliar applications of urea were assessed as a means of vineyard N amelioration at cover cropped sites comprised of Petit Manseng and Sauvignon blanc (Vitis vinifera L.). Perennial White and Crimson clover cover crops and foliar urea applications were also used in a Vidal blanc (Vitis spp.) vineyard. Treatments were imposed in the Sauvignon blanc vineyard for five years. The Petit Manseng and Vidal blanc vineyards were subjected to treatments for two years. Soil-applied N at bloom was most effective at increasing leaf petiole N at véraison, season-long chlorophyll content index (CCI), vine capacity and fruit yield. Fruit yield was increased due to more berries per cluster and greater berry weights. Increased rates of soil-applied N decreased the fruit weight:pruning weight ratio. Clover cover crops offered little to no benefit as a N source in the two-year period of evaluation. None of the N management schemes negatively impacted canopy density, fruit zone light interception, or botrytis bunch rot incidence. The combination of both a soil-applied and foliar-applied N fertilizer may be the most effective means to increase both vine capacity and YAN in vineyards where vineyard floor cover crops are compromising vine N status. / Master of Science
54

Groundcover, rootstock and root restriction effects on vegetative growth, crop yield components, and fruit composition of Cabernet Sauvignon

Hatch, Tremain Archer 09 March 2010 (has links)
Wine vineyards in humid environments like the mid-Atlantic United States are characterized by vines that develop too much vegetative growth for optimum quality wine production. Cover crops, rootstocks and rootzone restriction were evaluated for their effect on vegetative and reproductive growth on Cabernet Sauvignon. Treatments were arranged in a strip-split-split plot arrangement with under-trellis cover crops (UTCC) compared to row-middle only cover crop combined with 1-m weed-free strips in the vine row as main plots. Rootstocks riparia Gloire, 420-A, and 101-14 were sub-plots, while sub-sub-plots comprised two treatments: vines were either planted in root-restrictive (RR), fabric bags (0.016 m3) at vineyard establishment (2006), or were planted without root restriction. All three factors were effective in suppressing vegetative development as measured by rate and extent of shoot growth, lateral shoot development, trunk circumference, and dormant pruning weights. Canopies of vines with UTCC and RR had reduced leaf layer values by approximately 21% and 23% compared to conventional controls. The principal effect of the UTCC and the RR treatments was a sustained reduction in stem (xylem) water potential. UTCC and RR caused significant 7 and 10% reductions in berry weight, compared to their conventional controls. Berry weights of vines grafted to riparia were greater than those of vines grafted to other rootstocks. Wine made from UTCC and RR treatments increased red wine color compared to herbicide UTGC and NRR, respectively. This study identified treatments that improve vine balance while simultaneously improving grape composition and potential wine quality. / Master of Science
55

Assessment of Vineyard Nitrogen Management upon Grape Chemistry

Moss, James Russell 27 August 2016 (has links)
To combat excessive vine vigor, many vintners have employed intensive cover cropping techniques. While cover crops provide a multitude of benefits to the farming system, they can compete for nutrients and water. The seemingly ubiquitous adoption of cover crops in the Eastern United States has led to vines and grape musts which are deficient in nitrogen (N). A must that is deficient in yeast assimilable nitrogen (YAN) can lead to the production of off aromas and stuck or sluggish fermentations. It has also been suggested that musts with limited amino nitrogen sources can result in wines with less fruity aromas than those with a higher starting amino acid content. Varying rates of calcium nitrate were applied to the soil at bloom and foliar urea was sprayed at a Sauvignon blanc and Petit Manseng (Vitis vinifera L.) vineyard. Perennial White and Crimson clover as well as foliar urea applications at véraison were utilized at a Vidal blanc (Vitis spp.) site. Foliar urea was effective at significantly increasing YANs in all experiments with some year to year variation in efficacy. Foliar urea applications slightly favored the production of ammonia over primary amino nitrogen. While most of the measured amino acids in fruit increased in concentration with the application of either soil or foliar N, foliar applications were more effective at increasing fruit amino acids. Of the amino acids measured, arginine and glutamine were the most increased by foliar urea applications, whereas proline was relatively unaffected. The use of clover as a perennial under-vine cover crop did not increase berry YAN. The application of foliar urea sprays may present an effective means by which vintners can easily increase must YANs and amino acid contents. / Master of Science in Life Sciences
56

Développement d'une méthode de comparaison de données asynchrones en vue de la formalisation d'un raisonnement par analogies : application à l'aide à la décision en viticulture / Development of a method to compare asynchronous data to a future analogy-based reasoning : application to decision support in viticulture.

Dupin, Séverine 03 July 2012 (has links)
L'objectif initial de ce travail de thèse est de valoriser les informations relatives au suivi temporel de la vigne, du raisin et de l'environnement de la plante et enregistrées dans des bases de données (BD) de traçabilité pour permettre la comparaison entre parcelles et millésimes, en vue de décisions par analogies.Les travaux réalisés durant cette thèse ont permis de proposer une méthode de transformation qui permet de représenter des ensembles de données asynchrones dans un espace commun afin de les comparer. Cette méthode s'appuie sur l'expertise du système de production. Dans ce travail de thèse, cette méthode a été appliquée à la comparaison de couples parcelle×millésime.L'expertise du système de production viticole permet, dans une première phase, de définir (i) la forme générale de la cinétique d'évolution de grandeurs de mesures évaluées sur la vigne, le raisin ou l'environnement de la plante et (ii) l'effet du climat sur la plante. Cette expertise est utilisée, dans une seconde phase, pour proposer des modèles paramétriques de l'évolution de chaque grandeur. Les données de suivi de chaque couple parcelle×millésime permettent d'ajuster les paramètres du modèle. Un vecteur de paramètres est défini par couple parcelle×millésime. Ce vecteur représente l'espace commun qui rend les couples parcelle×millésime comparables. Deux stratégies de comparaison sontalors possibles : (i) les comparaisons sont réalisées à partir des paramètres (méthode intensive), ou (ii) les comparaisons sont réalisées à partir de l'estimation de la valeur de la grandeur pour chaque couple parcelle×millésime et chaque unité de temps, commune à tous les couples (méthode extensive).Cette méthode a été appliquée à trois exemples différents.Dans une première application, les climats de différents millésimes intervenus sur différents cépages, entre la floraison et la véraison, ont été comparés entre eux après modélisation des grandeurs de mesure climatiques, à l'aide de modèles très simples.Dans une seconde puis une troisième application, la cinétique d'augmentation du pH et d'accumulation des sucres dans les baies de raisin pendant la maturation a été modélisée sous la forme d'une sigmoïde. Les comparaisons ont ensuite été réalisées en travaillant sur (i) la courbe représentative de chaque cinétique (pH), (ii) les paramètres du modèle (sucres) et (iii) une estimation journalière de la concentration en sucres dans les baies.Les bases de données utilisées dans ces applications proviennent de deux régions très différentes. Des données issues du suivi de la station expérimentale INRA Pech Rouge en Languedoc-Roussillon, dans le sud de la France, ont été utilisées pour l'application 1 et une partie de l'application 3. Des données de suivi de différents domaines de la Napa Valley en Californie ont servi pour l'application 2 et une partie de l'application 3.Le changement d'espace de représentation des données apporte une connaissance nouvelle pour décrire les individus et les phénomènes temporels de la vigne. Cette connaissance pourrait permettre de formaliser un raisonnement par analogies utilisant et valorisant l'expérience passée pour la gestion du millésime en cours. / The initial objective of this thesis is to enhance the in-time follow-up information of the vine, the grape and the environment of the plant stored in traceability databases (BD) traceability to allow comparison between plots and vintages, to a future analogy-based decision support.The work done during this thesis allowed to propose a transformation method for representing sets of asynchronous data in a common space for comparison. This method relies on the expertise of the production system. In this thesis, this method was applied to the comparison of pairs of plot×vintage.The expert knowledge of the vineyard production system allows, in a first phase, to define (i) the general shape of the kinetics of on the vine, the grapes or the plant environment measured grandeurs, and (ii) the effect of the climate on the plant.This expertise is used in a second phase, to propose parametrical models that represent each grandeur kinetic. Monitoring data of each pair plot×vintage are used to adjust the model parameters. A vector of parameters is defined for each pair plot×vintage. This vector represents the common space that makes pairs of plot×vintage comparable. Two comparison strategies are possible: (i) comparisons are made from the parameters (intensive method), or (ii) comparisons are made from the estimation of the value of the quantity for each pair plot×vintage and each time unit, common to all pairs (extensive method).This method was applied to three different examples.In a first application, the climate of different vintages occurred on different grape varieties, between flowering and veraison, were compared with each other after modeling of the measured climate grandeurs, with very simple models.In a second and a third application, the kinetics of the increase of pH and accumulation of sugars in grape berries during ripening was modeled using a sigmoid. Comparisons were then made by working on (i) the graph of each kinetic (pH), (ii) parameters (sugars) and (iii) an estimation of the daily sugar concentration in berries.The databases used in these applications come from two very different winegrowing regions. Data from the monitoring of the INRA Pech Rouge Experimental Station, in Languedoc-Roussillon in the south of France, were used for the application 1 and part of the application 3. Monitoring data from different estates of Napa Valley in California were used for the application 2 and part of the application 3.The change of space where data are represented constitutes a new knowledge that permit one to describe individuals and temporal phenomena of the vine. This knowledge could allow to formalize an analogy-based reasoning that uses and promotes past experience to manage the current vintage.
57

Efeito protetor de fitomedicamento Vitis Vinifera L na lesão renal aguda induzida pelo Tacrolimus / Protective effect of the phytomedicine Vitis Vinifera L in acute kidney injury by Tacrolimus

Silva, Wanessa Teixeira 04 November 2010 (has links)
As lesões renais agudas (LRAs) nefrotóxicas correspondem a 30% dos casos de LRA. A nefrotoxicidade é efeito indesejável de diversos fármacos de uso rotineiro na clínica, entre eles as drogas imunossupressoras. A nefrotoxicidade do Tracolimus (Fk 506) é uma das causas de LRA após o transplante renal. Com a ampla utilização do Fk 506 nas terapias imunossupressoras e devido ao seu potencial nefrotóxico que pode levar à perda do enxerto, o objetivo desse estudo foi avaliar o efeito renoprotetor do extrato de Vitis vinifera L, um fitomedicamento com efeito antiinflamatório e antioxidante, na nefrotoxicidade induzida pelo Tacrolimus em ratos. Foram utilizados ratos Wistar, machos, adultos, pesando entre 250 - 300g, todos tratados 1x/dia por 5 dias, conforme os seguintes grupos: Salina (grupo controle) (NaCl 0,9%, 0,1ml por gavagem); Vitis (Vitis vinifera L 3mg/kg por gavagem), Fk (Tacrolimus 0,5mg/kg por gavagem) e Fk+Vitis (Tacrolimus 0,5mg/kg + 3mg/kg por gavagem). Foram avaliados a função renal (FR) (clearance de creatinina, método Jaffé); os peróxidos urinários (PU) (FOX-2), o malondealdeído (MDA-TBARS) e a histologia renal. Os dados desse estudo confirmaram a lesão nefrotóxica de caráter oxidativo induzida pelo Tacrolimus. A Vitis vinifera L demonstrou efeito renoprotetor significativo, com melhora na FR, redução dos níveis de peroxidação lipídica e proteção histológica. Esse estudo confirmou a renoproteção da Vitis vinifera L na LRA induzida pelo Tacrolimus. / The nephrotoxic injury corresponds to 30% of the acute kidney injury (AKI) cases. Nephrotoxicity is an undesirable effect of several drugs used in the clinic, among them, the imunossupressoras drugs. The Tacrolimus (FK 506) nephrotoxicity is the main cause of AKI after kidney transplantation. Being Fk 506 widely used in the immunessupressive therapies and due to its nephrotoxic effect that can lead to the loss of graft, the aim of this study was evaluate the renoprotective action of Vitis Vinifera L extract , a phitomedicine with antioxidant and antinflammatory effects in the nephrotoxicity induced by FK 506 in rats. Wistar rats, male, adults, weight ranging from 250-300g were used, all treated once/day for 5 days, as the following groups: Saline (control group) (NaCl 0.9%, 0,1ml per gavage), Vitis (Vitis vinifera L, 3mg/Kg per gavage), FK (Tacrolimus 0.5mg/Kg per gavage) and FK+Vitis (Tacrolimus 0.5mg/Kg per gavage + Vitis vinifera L, 3mg/Kg per gavage). Renal Function (RF) (creatinine clearance, Jaffé method), urinary peroxides (FOX-2), malondialdehyde (MDA-TBARS) and the kidney histological were evaluated. The data of this study confirmed the oxidative kidney injury by Tacrolimus. The Vitis vinifera L showed significant renoprotective effect, with improvement in the RF, a reductin in lipid peroxidation and histological protection. This study confirmed the renoprotective effect of Vitis Vinifera in the AKI by Tacrolimus.
58

Bioecologia e tratamento quarentenário de Ceratitis capitata (Wiedemann 1824) (Diptera: Tephritidae) com raios X em uvas de mesa do Submédio do Vale do São Francisco / Bioecology and quarantine treatment of Ceratitis capitata (Wiedemann 1824) (Diptera: Tephritidae), with x-rays on table grapes in the São Francisco Valley

Pacheco, Maylen Gómez 30 November 2016 (has links)
O Submédio do Vale do São Francisco (VSF), que compreende parte dos estados da Bahia e de Pernambuco, é considerado atualmente o principal polo de produção de uvas frescas para exportação do Brasil. Entre as principais pragas que afetam essa cultura na região destaca-se a mosca-das-frutas, Ceratitis capitata, conhecida como moscamed ou mosca-do-mediterrâneo. Para a viticultura do VSF, populações elevadas de C. capitata representam o principal problema quarentenário para as exportações de uvas in natura, e tratamento quarentenário a frio, na pós-colheita, é obrigatório para uvas que se destinam aos Estados Unidos, Japão e Mercosul, onerando o custo final de produção. Visando aperfeiçoar as estratégias de manejo de C. capitata nessa cultura, o presente trabalho teve como objetivos estudar a biologia e comportamento desse inseto em cultivares de uvas de mesa produzidas no VSF, assim como avaliar o uso da radiação X como tratamento pós-colheita de cachos de uvas. Dados de estudos de preferência de oviposição e biologia de C. capitata em quatro cultivares de uvas de mesa, duas vermelhas (?Benitaka\' com semente e ?Crimson\' sem semente) e duas brancas (?Itália\' com semente e ?Festival\' sem semente) mostraram que esse inseto manifesta preferência de oviposição por bagas de cultivares vermelhas (Benitaka e Crimson), em condições de livre escolha. A cultivar de uva utilizada pelas larvas de C. capitata como alimento influenciou no desenvolvimento e sobrevivência dos estágios imaturos biológico, bem como no comportamento reprodutivo, longevidade e parâmetros demográficos das coortes de C. capitata recuperadas. Os valores estimados de Ro, rm e ? para coortes estudadas reafirmam que C. capitata se caracteriza por ser uma espécie com um alto potencial de crescimento e que as cultivares avaliadas constituem hospedeiros favoráveis à multiplicação desse inseto. Além disso, os resultados obtidos mostraram que C. capitata manifesta preferência de oviposição em cachos de uva Itália com maturação fisiológica mais avançada, em condições de escolha. No entanto, as fêmeas podem iniciar o ataque nas bagas, em parreirais desta variedade, aos 60 dias após a poda das plantas, quando os frutos ainda apresentam características físico-químicas desfavoráveis para a oviposição e desenvolvimento das fases imaturas, tais como: elevada firmeza e acidez e baixo teor de SST. As doses letais, DL99,9968, para inibir a emergência de adultos, quando aplicadas sobre ovos de 48h e larvas jovens (L1) infestando bagas de uvas Itália, foram estimadas em 12,08 e 20,44 Gy, respectivamente. Parâmetros químicos e sensoriais não foram afetados pela exposição das uvas às diferentes doses de raios X testadas, após 72h de armazenamento. Os conhecimentos biológicos, comportamentais e demográficos obtidos na presente pesquisa contribuirão ao aperfeiçoamento das estratégias de manejo de C. capitata nesta cultura, nas condições do VSF / The Lower Basin of the San Francisco Valley (VSF), which includes part of the states of Bahia and Pernambuco, is currently considered the major exporter and producer of table grapes in Brazil. Ceratitis capitata, also known as Moscamed or Mediterranean fly is among the main pests affecting fruit crops in the region. For the viticulture of the VSF, high populations of C. capitata are considered the main quarantine problem for exports of fresh table grapes, and for that reason post-harvest quarantine cold treatment is compulsory for grapes aimed to markets like the United States, Japan and Mercosur, adding additional charges to the final production cost. In order to improve the management strategies against C. capitata in this crop, this research aimed to study the biology and behavior of this insect in some table grape varieties grown in the VSF, as well as evaluate the use of Xrays as post-harvest treatment in table grape bunches. Studies on C. capitata oviposition preference and biology in four varieties of table grapes, two red (\'Benitaka\' seeded and \'Crimson\' seedless) and two white (\'Itália\' seeded and \'Festival\' seedless) showed that this insect expresses an oviposition preference for berries on red cultivars (Benitaka and Crimson), under free choice conditions. The table grape cultivar used for medfly larvae as food also influenced the development and survival of biologically immature stages as well as on reproductive performance, longevity and demographic parameters of C. capitata cohorts originating from the studied table grape varieties studied. The estimated values of Ro, rm and ? for the studied cohorts reaffirm that C. capitata is characterized by being a specie with a high growth potential and that the cultivars used in this research are favorable hosts for the multiplication of this insect. In addition, the results showed that C. capitata under choice conditions has clear preference of oviposition in \'Itália\' bunches in advanced physiological maturity. However, females can start attacking berries of this variety in vineyards, only 60 days after pruning, when the fruits still have unfavorable physicochemical characteristics for oviposition and immature stages development, such as high firmness and acidity and low in SST. The lethal dose, DL99,9968 to inhibit the emergence of adults when applied on 48 hours eggs and young larvae (L1) infesting \'Itália\' grape berries were estimated at 12,08 and 20,44 Gy, respectively. Chemical and sensory parameters were not affected by the exposure of table grapes to the different X-ray doses tested after 72 hours of storage. Biological, behavioral and demographic knowledge obtained in this study will contribute to the improvement of C. capitata management strategies in this crop under the VSF conditions
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Diversité et évolution chez Vitis vinfera L. de traits impliqués dans le syndrome de domestication et dans la biologie de la reproduction / Diversity and evolution of traits implicated in reproduction biology and in domestication syndrom in wild grape (Vitis vinifera ssp. sylvestris) and domesticated grape (Vitis vinifera ssp. sativa)

Picq, Sandrine 09 February 2012 (has links)
La domestication est un processus évolutif complexe au sein duquel les pressions de sélection exercées par l'Homme conduisent à des changements morphologiques et physiologiques importants qui permettent de différencier sans ambigüité les espèces domestiquées de leurs ancêtres sauvages. Les récentes études archéobotaniques, génétiques et génomiques sur différentes plantes annuelles telles que notamment, le maïs (Zea mays L.), le riz (Oryza sativa L.) ou la tomate (Solanum lycopersicum L.) ont considérablement fait progresser notre compréhension de la domestication des plantes. A la différence des espèces annuelles, la domestication des plantes pérennes, en particulier les espèces fruitières, reste énigmatique.Dans ce contexte, l'objectif de ce travail est de contribuer à la compréhension du processus de domestication d'une plante pérenne fruitière emblématique, la vigne (Vitis vinifera L.) à travers l'étude de la diversité et de l'évolution de deux caractères majeurs du syndrome de domestication : la forme du pépin et le système de reproduction. Nos travaux sur la morphologie du pépin appréhendée par la méthode des transformées elliptiques de Fourier ont révélé des relations significatives entre la forme du pépin, le statut taxonomique (sauvage – domestiqué), l'origine géographique des cépages et leurs liens de parenté corroborant les résultats d'analyses génétiques acquises antérieurement. D'autre part, le changement de forme du pépin se produisant au cours de la domestication serait intimement lié à l'augmentation de la taille de la baie due aux pressions de sélection exercée par l'Homme. Concernant la transition de la diécie vers l'hermaphrodisme opérée au cours de la domestication, l'analyse du polymorphisme de séquences du locus du sexe a révélé que les vignes domestiquées seraient les descendantes d'individus mâles capables de produire des baies. Le patron de diversité de ces mêmes séquences corrobore l'idée d'un événement de domestication majeur de la vigne dans le Proche Orient et témoigne de l'existence d'introgressions du compartiment domestiqué par le compartiment sauvage dans l'Ouest du bassin Méditerranéen. / Domestication is a complex evolutionary process in which, human selection pressures lead to great morphological and physiological changes that allow to differentiate domesticated species from their wild ancestors. Recent archaeobotanical, genetic and genomic studies of various annual crops such as maize (Zea mays L.), rice (Oryza sativa L.) and tomato (Solanum lycopersicum L.) have significantly advanced our understanding of plant domestication. However, the domestication of perennial plants, particularly fruit trees, remains poorly documented compared to the domestication of annual crop plants.In this framework, this work aims to contribute to the understanding of the domestication process of the emblematic perennial plant, the grapevine (Vitis vinifera L.) through the study of diversity and evolution of two major traits of the domestication syndrome: the seed shape and the reproductive system. Our work on seed shape based on the method of the elliptic Fourier transforms revealed significant relationships between seed shape, the taxonomic status (wild – domesticated), the geographic origin of cultivars and their parentage relationships, corroborating former results from genetic analysis. On the other hand, seed shape changes occurred during domestication seem to be linked to the increase of the berry size as the consequence of major human selection pressures. Regarding the transition from diecy to hermaphroditism to diecy operated during domestication, the analysis of sequence polymorphism in the sex locus revealed that domesticated grapevine would be the descendant of wild male individuals able to produce berries. The pattern of diversity of these sequences supports the hypothesis of the occurrence of a major domestication event in the Near East and testify of introgressions of Western European cultivars by local wild grapes.
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Adubação nitrogenada em videira: Perdas e mineralização de nitrogênio / Niitrogen fertilization on vine: Losses and minieralization of nitrogen

Lorensini, Felipe 29 July 2011 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Since 1980, native fields of the Campanha Gaúcha from Rio Grande do Sul State (RS) have been incorporated into the grape production. In this region, vines has been cultivated under sandy soils with low organic matter content; therefore they have a low nitrogen (N) supply capacity and inputs of N through organic or mineral sources are necessary. Although, some N may be lose by volatilization or leaching. In addition, the amount of N mineralized along the plant s cycle is unknown. The objective was to evaluate N loses by volatilization and leaching, such as to quantify the N mineralization rates in soils cultivated with vines and fertilized with different sources of N. In order to evaluate the loses, two experiments were carried out in Cabernet Sauvignon vines in Rosário do Sul (RS). The experiment 1 consisted on the installation of lysimeters on the rows and application of 0, 40, 80 and 120 kg N ha-1, as urea, to collect and analyze the mineral N leached. On the experiment 2, urea was applied in amounts of 0, 20, 40, and 80 kg N ha-1 year-1. Also, application of 40 kg N ha-1 year-1 of organic compost and 40 kg N ha-1 year-1 as polymer coated urea were used to evaluate the N volatilization as N-NH3. To evaluate the mineralization rates, incubations were carried out at the laboratory during 141 days, using Sandy Typic Hapludalf soils, collected from 0-20 cm layer. In the moment of incubation, an amount of 40 Kg N ha-1 of organic compost, polymer coated urea and urea were added on the soils. One sample was collected from a native field as reference treatment. Mineral N concentration in the leached solution, especially along the vine sprouting, increased according to the fertilizers rates applied on the sprouting beginning. The fluxes and loses of N-NH3 from vine soils to the atmosphere had increased according to the mineral N rate. Polymer coated urea and organic compost showed the lowest loses of N-NH3 by volatilization. A higher mineralization was observed up to the 38th day of incubation when polymer coated urea and urea was distributed on soil surface. The N releasing of compost applied on vine soils has a better synchronism to the plant requirements, comparing to polymer coated urea or urea. The N storage in the soil, which may be mineralized of native or vine fields, is able to supply the vine requirements. / No Rio Grande do Sul (RS), a partir da década de 80, campos nativos da Campanha Gaúcha foram incorporados ao sistema de produção de uvas. Nesta região as videiras são cultivadas em solos com textura arenosa e com baixo teor de matéria orgânica. Isso lhes confere baixa capacidade de fornecimento de nitrogênio (N) e torna-se necessário a aplicação de fertilizantes nitrogenados de fontes minerais e/ou orgânicas. Porém, parte do N aplicado pode ser perdido por volatilização ou lixiviação. Além disso, a quantidade do nutriente mineralizado ao longo do ciclo das videiras é desconhecida. O trabalho objetivou avaliar as perdas de N por volatilização e lixiviação e a taxa de mineralização de N em solo cultivado com videira e submetido à adubação nitrogenada. Para avaliação das perdas foram instalados dois experimentos em um vinhedo comercial de Cabernet Sauvignon, em Rosário do Sul (RS). O experimento 1 recebeu doses de 0, 40, 80 e 120 kg de N ha-1 ano -1 na forma de uréia e foram instalados lisímetros nas linhas de plantio das videiras para a coleta da solução e análise da concentração de N mineral. No experimento 2 foram instaladas câmaras coletoras no solo, nas linhas de plantio, que receberam aplicações de 0, 20, 40, e 80 kg de N ha-1 ano-1, na forma de uréia, 40 kg de N ha-1 ano-1 de composto orgânico e 40 kg de N ha-1 ano-1 de uréia revestida com polímeros, para avaliar a volatilização de N-NH3. Para avaliar a taxa de mineralização foi realizada uma incubação em laboratório durante 141 dias com as amostras coletadas na camada de 0-20 cm de um solo Argissolo Vermelho com histórico de cultivo de videiras. Ao serem incubados, os solos receberam a adição de composto orgânico, uréia revestida com polímeros e uréia, na dose de 40 Kg ha-1, para todos os tratamentos. Amostras de uma área de campo nativo foram coletadas e utilizadas como referência. As concentrações de N mineral na solução percolada, especialmente ao longo do estádio de brotação das videiras, aumentaram com a dose do fertilizante mineral aplicado no início deste período. Os fluxos e perdas de N-NH3 do solo para a atmosfera em áreas cultivadas com videira aumentaram com a dose de N mineral aplicado. A aplicação de uréia revestida com polímeros e a aplicação de composto orgânico promoveram as menores perdas de N-NH3 por volatilização. No solo de vinhedo submetido à aplicação de uréia revestida com polímeros e uréia na superfície do solo, a maior mineralização de N aconteceu até os 38 dias de incubação. A liberação de N do composto orgânico aplicado no solo de vinhedo tem um maior sincronismo com a necessidade da videira pelo nutriente, quando comparado à uréia revestida e uréia. As reservas de N total, potencialmente mineralizáveis, dos solos de campo nativo e de vinhedos, são suficientes para suprir a demanda da videira.

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