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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.
71

Avaliação biológica de estruturas florais em macieira e sua relação com a qualidade do fruto

MADAIL, Rafael Hansen 20 February 2008 (has links)
Made available in DSpace on 2014-08-20T13:59:10Z (GMT). No. of bitstreams: 1 dissertacao_rafael_hansen_madail.pdf: 1935975 bytes, checksum: 906f999870a0ef1b6bd50a13c3473a76 (MD5) Previous issue date: 2008-02-20 / The apple tree is characterized by the different floral structures. Several researches show a relationship between the production and fruit quality and the original fruiting structure. The aim of this study was to evaluate the relationship between the floral structure and the fruit quality in the cultivars Gala, Fuji and Daiane in the mild climatic conditions in the south of Brazil. Six types of fruiting structures were characterized according to their nature and the bud size: spur of weak bud and spur of vigorous bud, short twig of terminal growth of weak bud and short twig of terminal growth of vigorous bud and long twig of terminal growth of weak spur and vigorous spur. For these different structures, were evaluated characteristics related to the phenological development, like the average dates of each phenological state and the percentage of buds that reached the different phenological phases. Patterns related to the productive potential and the fruit quality were evaluated, like the sprout and fruit set index, bud abortion index and percentage of vegetative buds, leaf area, number of flower per cluster and the length / diameter ratio of the fruits. In Gala and Fuji cultivars, the long twigs had the earlier phenological development and in Daiane, the earlier structure to sprout were the spurs. But in the three cultivars the highest percentage of buds in each phenological phase were found in the long twigs. The long twigs showed the highest sprout and fruit set index, as well as the major number of flowers per cluster and leaf area in the three cultivars, while the spurs showed the lowest results. The highest bud abortion index was found in the spurs and the lowest in the long twigs. According to the data found for the fruit shape, no difference was found in the cultivars Gala and Fuji. In the cultivar Daiane, however, the fruits with the highest length / diameter ratio were found in the long twigs. / A macieira é caracterizada por apresentar diferentes estruturas florais. Vários estudos apontam uma relação entre a produção e a qualidade dos frutos com a estrutura frutífera de origem. O objetivo deste estudo foi avaliar a relação existente entre o órgão de frutificação e a qualidade do fruto nas cultivares Gala, Fuji e Daiane nas condições de clima ameno do sul do Brasil. Foram caracterizados seis tipos de estruturas frutíferas de acordo com a natureza e o diâmetro da gema (esporão de gema fraca e esporão de gema vigorosa, brindila curta de gema fraca e brindila curta de gema vigorosa, brindila longa de gema fraca e brindila longa de gema vigorosa). Nestas diferentes estruturas foram avaliados parâmetros ligados ao desenvolvimento fenológico, como as datas médias para cada um dos estádios de desenvolvimento e a percentagem de gemas que atingiram os diferentes estádios. Também foram avaliadas características relacionadas ao potencial de produção e a qualidade dos frutos, como o índice de brotação e frutificação efetiva, índice de abortamento, percentagem de gemas vegetativas, área foliar, número de flores por cacho floral e a razão entre o comprimento e o diâmetro dos frutos. Nas cultivares Gala e Fuji as estruturas que floresceram primeiro foram as brindilas longas, enquanto na cultivar Daiane as estruturas mais precoces foram os esporões. No entanto as três cultivares apresentaram a maior percentagem de gemas por estádio fenológico nas brindilas longas. As brindilas longas também foram as estruturas com maiores taxas de brotação e frutificação efetiva, bem como maior número de flores por cacho floral e maior área foliar nas três cultivares, enquanto os esporões apresentaram os menores resultados. O maior abortamento de gemas foi encontrado nos esporões, e o menor nas brindilas longas. Com relação ao formato dos frutos, não houve diferença entre as estruturas nas cultivares Gala e Fuji. Na cultivar Daiane, no entanto, os frutos com maior razão comprimento / diâmetro foram encontrados nas brindilas longas.
72

Eficiência de doses de nitrogênio e sombreamento na cultura do tomate em cultivo protegido / Efficiency of nitrogen doses and shading on tomato culture in protected cultivation

Morais, Tassiane Bolzan 03 March 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Several factors influence the productivity and end quality of the fruits of the tomato crop, among them, mineral nutrition, especially nitrogen nutrients and factors that interfere with the culture environment of the crop, such as shading of plants. Aiming to maintain the productivity and quality of the tomato fruits in the off season of the crop in RS, the objective of this work was to evaluate the influence of 50% black shading screen, nitrogen fertilization and the interaction between the two factors, on the agronomic performance of the tomato crop under protected environment. The present work was conducted in the greenhouse at the Biomonte Research and Development Company, in the agricultural crop 2016, geographical coordinates 29 ° 39,059 'South and 53 ° 57,413' West and altitude of 180.0 meters. The experiment was in DIC (completely randomized design) with factorial arrangement 2 x 5, and twenty repetitions. Two environments were used (with and without black shading screen 50%, sombrite® type) and five doses of N (0, 75, 150, 225 and 300 kg ha-1), according to the need of the crop and soil analysis used in the experiment, being the dose of 150 kg ha-1 of N, the recommended dose for the conditions of the present study. In order to evaluate the agronomic performance and crop productivity, were verified daily the climatic variables in the two environments and quantified the height and diameter of the plants, leaf area, chlorophyll content, stomatal behavior, yield (weight, diameter and length of fruits) and dry mass of shoots; for the evaluation of fruit quality, the pH, soluble solids, titratable acidity and SS / AT ratio of tomato fruit pulp were analyzed. The factors shading and N doses had influence on the agronomic performance, productivity and quality of tomato fruits, in cultivation in a protected environment. In the present experiment, the variables analyzed presented better responses in the non-shading condition of the plants than in the shaded plants. With regard to nitrogen, nutrient application contributed to a better growth and development of the plants, crop productivity and fruit quality up to a given dose (225 kg ha-1 in both environments). At the doses prior to and at the subsequent doses, tomato plants showed lower growth and development and lower productivity and fruit quality, indicating toxicity caused by excess N. From these data, it was concluded that, the conditions of the Experiment, for the option of cultivating the tomato under protected environment, in the crop off season, the dose of N used should be adjusted for higher fruit productivity and quality, and it is not necessary to use a 50% black shading screen. / Diversos são os fatores que influenciam na produtividade e na qualidade final dos frutos da cultura do tomate. Dentre eles, destaca-se a nutrição mineral, especialmente, o nutriente nitrogênio e fatores que interferem no ambiente de cultivo da cultura, como o sombreamento das plantas. Visando manter a produtividade e a qualidade dos frutos de tomate na entressafra da cultura no RS, o objetivo deste trabalho foi avaliar a influência da adubação nitrogenada, do sombreamento e a interação entre os dois fatores, sobre o desempenho agronômico da cultura do tomateiro, sob ambiente protegido. O presente trabalho foi conduzido na casa de vegetação na Empresa Biomonte Pesquisa e Desenvolvimento, na safra agrícola 2016. O experimento foi um DIC (delineamento inteiramente casualizado), com esquema fatorial 2 x 5, com vinte repetições. Foram utilizados dois ambientes (com e sem tela de sombreamento preta 50%, do tipo sombrite®) e cinco doses de N (0, 75, 150, 225 e 300 kg ha-1), conforme a necessidade da cultura e análise do solo utilizado no experimento, sendo a dose de 150 kg ha-1 de N, a recomendada para as condições do presente estudo. Para avaliação do desempenho agronômico e da produtividade da cultura, foram verificadas as variáveis climáticas nos dois ambientes e quantificados a altura e diâmetro das plantas, área foliar, teor de clorofila, comportamento estomático, produção (peso, diâmetro e comprimento dos frutos) e massa seca da parte aérea das plantas; para a avaliação da qualidade dos frutos, foram analisados o pH, sólidos solúveis, acidez titulável e relação SS/AT da polpa dos frutos do tomateiro. Os fatores sombreamento e doses de N apresentaram influência no desempenho agronômico, na produtividade e na qualidade de frutos de tomate, no cultivo em ambiente protegido. No presente experimento, as variáveis analisadas apresentaram melhores respostas em condição de não sombreamento das plantas do que sobre as plantas sombreadas. Com relação ao nitrogênio, a aplicação do nutriente contribuiu para um melhor crescimento e desenvolvimento das plantas, produtividade da cultura e qualidade dos frutos até determinada dose (225 kg ha-1 nos dois ambientes). Nas doses anteriores a essa e na dose subsequentes a essa, as plantas de tomate apresentaram menor crescimento e desenvolvimento e menor produtividade e qualidade dos frutos, indicando toxidez causada pelo excesso de N. A partir desses dados, conclui-se que, as condições do experimento, para a opção de cultivo do tomateiro sob ambiente protegido, na entressafra da cultura, a dose de N utilizada deve ser ajustada para maior produtividade e qualidade de frutos, não sendo necessário o uso de tela de sombreamento preta 50%.
73

Functional genomic characterization of fruit quality traits in apple (Malus x domestica Borkh)

Marondedze, Claudius January 2009 (has links)
Philosophiae Doctor - PhD / The domesticated apple (Malus x domestica Borkh), belonging to the Malusgenus of the Rosaceae family, is one of the edible pomaceous fruits. Since it is one of the important commercial fruit crops worldwide, the quality of the fruit is crucial to breeders and farmers as it ultimately determines acceptance of a cultivar for consumption. Fruit quality is also a critical determinant factor that is used to estimate the potential of apples to have a long shelf life / South Africa
74

Du gène au phénotype : contrôle génétique et modélisation du métabolisme des sucres chez la pêche / From gene to phenotype : Genetic control and modeling of sugar metabolism in peach

Desnoues, Elsa 13 March 2015 (has links)
La qualité du fruit est un caractère multicritère avec des relations antagonistes fréquentes. La perception de la qualité du fruit dépend fortement de l’équilibre entre les teneurs en sucres et acides. Parmi les 3 sucres dits majeurs dans les fruits que sont le saccharose, le glucose et le fructose, le fructose présente un pouvoir sucrant plus important et sa concentration est le facteur qui affecte le plus le goût sucré du fruit.L’objectif de cette thèse est d’analyser le métabolisme des sucres chez la pêche d’un point de vue métabolique, enzymatique et génétique et d’intégrer dans un modèle mathématique l’ensemble des informations obtenues. Ce travail porte plus particulièrement sur la mise en évidence de l’effet d’une perturbation de la teneur en fructose sur l’ensemble du métabolisme des sucres ainsi que sur la compréhension des mécanismes à l’origine de ce phénotype appelé ‘peu de fructose’. Une caractérisation biochimique quasi-exhaustive du métabolisme des sucres a été réalisée au cours du développement du fruit.Pour cela 6 métabolites et 12 capacités enzymatiques ont été mesurés chez 106 génotypes d’une population issue d’un croisement interspécifique. Cette étude a révélé une grande stabilité des capacités enzymatiques malgré l’importante variation des métabolites. Sur la base des données de 10 des génotypes, un modèle métabolique dynamique permettant de simuler l’accumulation des sucres au cours du développement du fruit a été développé et validé. Ce modèle permet de simuler des phénotypes contrastés et aide ainsi à l'exploration des mécanismes sous-jacents au phénotype ‘peu de fructose’. La caractérisation biochimique de la population a également fait l’objet d’une recherche de QTL. Cette étude a mis en exergue l’inconstance de l’effet de certains loci au cours du développement du fruit ainsi que des co-localisations de QTL de métabolites et capacités enzymatiques et de gènes candidats. Cette recherche a également confirmé la région génomique responsable du phénotype ‘peu de fructose’ au sein de laquelle un gène candidat fonctionnel a été mis en évidence. Il s’agit d’un gène homologue au transporteur vacuolaire exportateur de fructose (SWEET17) découvert récemment chez Arabidopsis. Une analyse de ce gène a été engagée afin de valider sa fonction et son implication dans le phénotype ‘peu de fructose’. Grâce à l’intégration des informations obtenues sur le contrôle génétique du métabolisme des sucres dans le modèle métabolique,une perspective de cette thèse sera de simuler les concentrations en sucres de génotypes virtuels ayant différentes combinaisons d’allèles. On pourra alors optimiser les combinaisons d’allèles pour augmenter les concentrations en sucres dans la pêche, ce qui donnera sans doute de nouvelles pistes à l’innovation variétale. / Fruit quality is a multi-criteria character with frequent antagonistic relationships. The perceptionof the fruit quality is highly dependent on the balance between the levels of sugars and acids. Among thethree so-called major sugars in fruit that are sucrose, glucose and fructose, fructose is the sweetest and itsconcentration is the factor that most affects the fruit sweetness. The objective of the present thesis is toanalyze the sugar metabolism in peach fruit from metabolic, enzymatic and genetic aspects and integrateinto a mathematical model all information obtained. This work focuses on the identification of the effect of alow fructose concentration on the whole sugar metabolism and the understanding of the mechanismsresponsible of this phenotype called ‘low-fructose-to-glucose-ratio’. A nearly exhaustive biochemicalcharacterization of sugar metabolism was conducted along peach fruit development. For this, 6 metabolitesand 12 enzyme capacities were assayed in 106 genotypes of a population derived from an interspecific cross.This study revealed a high stability of the enzyme capacities despite large variations of metabolites. Based ondata from 10 genotypes, a kinetic metabolic model that simulates the sugar accumulation in fruit wasdeveloped and validated. This model simulates contrasting phenotypes and helps in understanding theunderlying mechanisms of the ‘low-fructose-to-glucose-ratio’ phenotype. The biochemical characterizationof the population gave the opportunity to perform a QTL research. It highlighted the instability of the effectof certain loci along fruit development and QTL collocations of metabolites, enzyme capacities and candidategenes. It also confirmed the genomic region responsible for the ‘low-fructose-to-glucose-ratio’ phenotypewithin which a functional candidate gene was identified. It is a gene homologous to fructose vacuolartransporter (SWEET17) recently discovered in Arabidopsis. An analysis of this gene was engaged to validateits function and its responsibility in the ‘low-fructose-to-glucose-ratio’ phenotype. In the future, theintegration of the genetic control into the metabolic model will allow simulating virtual genotypes withdifferent combinations of alleles and predict their sugar content. Optimizing allele combinations to increasesugar concentrations in peach fruit will undoubtedly give new breeding opportunities.
75

Estudo de regiões genômicas envolvidas no metabolismo de aminoácidos e na determinação da estrutura da parede celular no tomateiro / Study of genomic regions involved in the metabolism of amino acids and in determining cell wall structure in tomato

Fabiana de Godoy 07 June 2013 (has links)
Embora o cultivo de tomate seja muito antigo e amplamente distribuído, ainda enfrenta desafios para o melhoramento dos níveis de produção e, da qualidade para o processamento e consumo fresco. A grande maioria das características de interesse agronômico está determinada por loci de caracteres quantitativos (QTL), dificultando ainda mais a identificação e transferência gênica. Diversas características tornam o tomateiro um bom modelo para estudos de dissecação dos determinantes genéticos de QTL. Primeiro, a disponibilidade de fontes de germoplasma selvagens ainda inexploradas que podem aumentar a variabilidade genética, somada à possibilidade de cruzamento entre espécies não simpátricas e à autogamia. Segundo, a grande quantidade de informação genética como mapas, coleções de ESTs, QTL, e populações de mapeamento. Terceiro, o genoma de S. lycopersicum está completamente sequenciado. Por fim, devido a suas diferenças morfogenéticas em relação à espécie modelo Arabidopsis thaliana, o tomate se torna uma alternativa para estudos de eudicotiledonias, principalmente em estudos relacionadas a metabolismo de frutos carnosos. A partir da abundante plataforma de dados disponível e por meio de ferramentas de genômica, e genética reversa, este trabalho aborda o estudo de duas regiões do genoma do tomateiro envolvidas no metabolismo de aminoácidos e na determinação da estrutura da parede celular. O estudo de genômica comparativa de uma região do cromossomo 7 permitiu revelar a perfeita sintenia existente entre S. lycopersicum e a espécies selvagem S. pennellii e estimar o tempo de divergência em 2,7 MAA. Complementarmente, foi possível determinar que as diferenças fenotípicas entre as espécies são maiormente devidas a mudanças nas regiões regulatórias e à presença de SNPs. O estudo funcional do gene LFP (Low Free Putrescine) permitiu caracterizar uma proteína plastidial, até o momento desconhecida em tomateiro, que participa do metabolismo de poliaminas. O silenciamento de LFP resultou na redução da disponibilidade de putrescina livre e no aumento da biomassa vegetativa. Por outro lado, os resultados obtidos do estudo do gene GAUT4 (galacturonosiltransferase 4) demonstraram que a enzima codificada se localiza em Golgi e participa do metabolismo das pectinas. Em frutos, a redução dos níveis de GAUT4 resultou na diminuição de pectina e na alteração da sua composição, porém estes se apresentaram mais firmes. Adicionalmente, o silenciamento do gene GAUT4 modificou o particionamento de açúcares provocando o aumento de massa vegetativa em detrimento do índice de colheita, revelando assim um mecanismo regulatório que comunica o metabolismo da parede celular ao controle da relação fonte-dreno. Desta forma, os resultados obtidos aportam dados fundamentais para a melhor compreensão de caracteres de interesse agronômico, assim como de processos fisiológicos complexos e pouco explorados até o momento no tomateiro / Although tomato is an old and widely distributed culture, it still faces challenges to improve production levels and quality for processing and consumption. The vast majority of agronomical important characteristics are determine by quantitative trait loci (QTL), further hindering the gene identification and transfer. Several features make tomato a good model for studying the genetic determinants underneath QTL. First, the availability of unexploited sources of wild germplasm that can increase genetic variability, coupled with the possibility of interbreeding between no sympatric species and autogamy. Second, the large amount of available genetic information as maps, EST collections, QTL, and an extensive collection of mapping populations. Third, the genome of S. lycopersicum is completely sequenced. Finally, due to their morphogenetic differences in relation to model species Arabidopsis thaliana, tomato becomes an alternative to eudicotyledons studies, especially in studies related to fleshy fruits metabolism. From the abundant data platform available and by means of genomic tools, and reverse genetics, this work addresses the study of two tomato genomic regions involved in amino acids and cell wall metabolisms. The comparative genomic study in a region of chromosome 7 has revealed the perfect synteny between S. lycopersicum and the wild species S. pennellii, and estimated the time of divergence between both species in 2.7 MYA. Additionally, it was possible to determine that the phenotypic differences between species are mostly due to changes in regulatory regions and the presence of SNPs. The functional study of LFP gene (Low Free Putrescine) allowed us to characterize a plastid protein, yet unknown in tomato, which participates in the metabolism of polyamines. The LFP silencing resulted in reduced availability of free putrescine and increased vegetative biomass. Furthermore, the functional characterization of the GAUT4 (galacturonosyltransferase 4) gene demonstrated that the encoded enzyme is located in the Golgi apparatus and participates in the pectin metabolism. In fruits, the reduced levels of GAUT4 resulted in decreased pectin and in the change of its composition. Additionally, GAUT4 gene silencing modified sugars partitioning leading to an increased vegetative biomass together with a drastic reduction of the harvest index. Thus, revealing a regulatory mechanism that communicates the cell wall metabolism to source-sink relationship control. Concluding, the results obtained contribute to a better understanding of agronomical important traits, as well as of complex physiological processes little explored in tomato so far
76

Regulated deficit irrigation in citrus: agronomic response and water stress indicators

Ballester Lurbe, Carlos 06 May 2013 (has links)
In the Mediterranean area water is a scarce natural resource and periods of drought are frequent. It is then important to increase water use efficiency of irrigated crops. In order to achieve this, one promising option is regulated deficit irrigation (RDI). RDI consists in reducing water application during stages of crop development when yield and fruit quality have low sensitivity to water stress. Full irrigation is provided during the rest of the season to maintain production and fruit quality at adequate levels (Behboudian and Mills, 1997). In citrus, flowering and fruit set are sensitive periods to water restrictions, because water stress during this period increases fruit drop (Ginestar and Castel 1996). The more appropriate phenological period for applying water restrictions seems to be the summer period providing that water applications returned at full dosage sufficiently before harvest in order to allow for compensation in fruit growth (Cohen and Goell 1988). Previous work by González-Altozano and Castel (1999) showed the feasibility of applying RDI in 'Clementina de Nules' and identified threshold values of plant water stress that allowed water savings of about 10-20% without any detrimental effect on yield or fruit size. It would be desirable now to study the extrapolation of these results to commercial orchards of citrus and assess the use of RDI in different citrus cultivars. Two RDI strategies (RDI-1, irrigated at 50% of crop evapotranspiration (ETc) during summer and; RDI-2, irrigated at 35% ETc during the same period to RDI-1) will be compared with a control treatment irrigated at full requirements. As the level of water stress reached by trees is the important factor when RDI strategies are applied, the study of accurate water stress indicators for citrus is also needed. Thus, during the period of water restrictions the use of sap flow and canopy temperature measurements, obtained by thermal imaging or by means of fixed infrared thermometer sensors, will be assessed and compared to classical methods like stem water potential and stomatal conductance. / Ballester Lurbe, C. (2013). Regulated deficit irrigation in citrus: agronomic response and water stress indicators [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/28582 / TESIS / Premios Extraordinarios de tesis doctorales
77

Genetic Analysis of Black Raspberry Breeding Germplasm

Willman, Matthew 24 October 2019 (has links)
No description available.
78

Quality Changes in Grafted Pepper (Capsicum annumm L.) Scion Fruit

Fisk, Tylar S. January 2017 (has links)
No description available.
79

Selection of new eggplant (Solanum melongena, L.) lines

Arias, Iliana Corría 15 June 2011 (has links)
In den letzten Jahren ist das Interesse der Europäer am Verbrauch „Exotischer Gemüsearten“ gewachsen wie z.B. für asiatische Auberginengenotypen, die sich in der Farbe, im Geschmack und der Form von den standardmäßigen dunklen violetten Auberginenfrüchten unterscheiden. Diese Entwicklung kann die Einführung und die Kommerzialisierung neuer asiatischer Auberginensorten in Westeuropa beeinflussen und dadurch die Vielfalt des Angebots mit diesem Gemüse in den gemäßigten Regionen erhöhen. Aus diesem Grund bestand das Ziel dieser Arbeit darin, einige asiatische Genotypen (hauptsächlich vietnamesischen Ursprung) hinsichtlich ihres Wachstums und Ertrags zu untersuchen und diese mit typischen „europäischen“ Sorten bei einer Kultivierung im Gewächshaus zu vergleichen. Außerdem sollte geprüft werden, ob die genetische Variabilität von Samenherkünften verwendet werden könnte, um Klone zu selektieren, die den Wachstumsbedingungen in den Gewächshäusern unter den Klimabedingungen in Deutschland angepasst sind. In den in vitro Experimenten ist die Reaktion von 5 Auberginengenotypen auf die Mikrovermehrung und auf die in vitro Verfahren ausgewertet worden. Zusätzlich wurden die Einflüsse von Wachstumsregulatoren, NAA und 2.4D, auf die Kallus- und Organbildung und indirekte Pflanzenregeneration in vitro untersucht, um Aussagen hinsichtlich der Nutzbarkeit von biotechnologischen Züchtungsmethoden, zu erhalten. Das in vitro Klonen wurde mit dem Ziel durchgeführt, Klone von ausgewählten 5 asiatischen Auberginengenotypen zu erhalten, um Aussagen zu ihrer vegetativen und generativen Entwicklung sowie dem Ertrag zu erhalten, und mit typischen „europäischen“ Sorten unter Gewächshausbedingungen zu vergleichen. Alle Genotypen wurden einer der hydroponischen Substratkultur im Gewächshaus kultiviert. Die Entwicklung der Genotypen in organischen und mineralischen Substrat wurde verglichen. Das organische Substrat hat zum besseren Wachstum aller Auberginengenotypen geführt. Die aus der in vitro Vermehrung erhaltenen Klone der asiatischen Auberginengenotypen entwickelten sich zu normalen Pflanzen, die einen typischen Habitus erreichten und teilweise einen Ertrag hatten, der mit dem der Kontrolle vergleichbar war. Die besten asiatischen Auberginenklone hatten ähnliche Ergebnisse wie die der Kontrolle sowohl im Stadium des Blühbeginns, als auch im Ertrag. Ein wichtiges Merkmal für die Auswahl einiger asiatischer Klone war ihre Fähigkeit frühzeitig zu blühen, vergleichbar mit den „europäischen“ Sorten. Die asiatischen Genotypen waren charakterisiert durch schmalere und leichtere Früchte mit einem guten Geschmack, weniger Samen und einer guten Konsistenz des Fruchtfleisches im Vergleich mit den „europäischen“ Sorten. Ausgehend von den Ergebnissen die in den Untersuchungen erzielt wurden, scheint es möglich, neue stabile Genotypen zu erhalten, die geeignet sind für eine Kultivierung in der „Substratkultur“ im Gewächshäusern und die ein Potenzial für den Erwerbsanbau unter europäischen Bedingungen haben. Für eine Optimierung der Wachstumsbedingungen, insbesondere das Formierungssystem, sind weitere Forschungsarbeiten erforderlich zumal diese Genotypen sehr starkwüchsig sind. Des Weiteren sollte der optimale Erntezeitpunkt und die Fruchtqualität untersucht werden. / Recently, there has been a growing interest of the Europeans in the consumption of „exotic vegetables“ like those of Asian eggplant genotypes different in colour, taste and shape from the traditional dark violet eggplant fruits. This may influence the introduction and commercialisation of Asian eggplant types in Western Europe, which will contribute to increase the biodiversity of this crop in temperate regions. Therefore, this work aimed at screening 4 Asian eggplant genotypes (mainly of Vietnamese origin) concerning their growth and yield in greenhouses in comparison to „European“ breeds. Moreover, it should be tested whether the genetic variability of seed progenies could be used to select plants adapted to the growing conditions in greenhouses under the climatic peculiarities in Germany. In in-vitro experiments the response of 5 selected eggplant genotypes to micropropagation and in-vitro manipulation has been evaluated. Further on the influence of plant growth regulators, e.g. NAA and 2,4 D, on the callus and organ formation, and indirect plant regeneration in-vitro were studied in preparation of use of biotechnological breeding methods later on. The in-vitro cloning was carried out with the aim to produce clones of 5 Asian eggplant genotypes to evaluate their vegetative and generative development, as well as the yield, in comparison with typical „European“ varieties under greenhouse conditions. All genotypes were cultivated in „substrate culture“ with drip irrigation. The influence of organic and mineral substrates on the growth and development of the eggplant genotypes was compared. The organic substrate favoured better growth of all eggplant genotypes. The in-vitro derived clones of Asian eggplant genotypes developed to normal plants that reached full maturity and some of them had a yield comparable with that of the controls, the typical „European“ varieties. The best Asian eggplant clones gave similar results as the controls in the beginning of flowering and the yield. The early flowering feature characteristic of some clones of Asian origin comparable to that of the typical „European“ varieties is very important for selection. Asian genotypes were characterized by smaller and lighter fruits having good taste, less seeds and good consistency in comparison with the „European“ varieties used as control. Derived from the results obtained in this research, it seems possible to obtain new stable genotypes for „substrate culture“ system in greenhouse with a potential for commercial production under European conditions. The optimization of growing conditions especially the pruning system needs further research for these very vigorously growing plant types. Further on studies regarding optimal harvesting time and fruit quality shall be done.
80

Desenvolvimento do pessegueiro em função da intensidade de poda verde / Development of the peach tree related to green pruning intensity

Rodrigues, Alessandro 12 September 2005 (has links)
O Estado de São Paulo caracteriza-se como o principal produtor de pêssegos (Prunus persica (L.) Batsch) para consumo "in natura" do Brasil. Devido ao cultivo ser realizado em diferentes regiões e pelo uso de cultivares precoces e bem precoces, a maioria da safra ocorre na estação da primavera, antecipadamente à região Sul do Brasil. Um dos problemas decorrentes do plantio de pessegueiros em regiões mais quentes, como o Estado de São Paulo, foi o aumento considerável da ferrugem (Tranzschelia discolor). A poda verde, realizada após a colheita dos frutos, mostra-se como um dos métodos culturais utilizados pelos produtores para o manejo desta doença. O trabalho de pesquisa objetivou verificar o efeito de intensidades de poda verde após a colheita, no desenvolvimento do pessegueiro e na severidade de ferrugem. O trabalho experimental foi realizado no Campus "Luiz de Queiroz" da Universidade de São Paulo, em Piracicaba, Departamento de Produção Vegetal, sendo composto dos seguintes tratamentos: T1: poda verde de intensidade leve (PL) e T2: poda verde de intensidade drástica (PD). A área útil do ensaio foi de 345,6 m2, constituída de 96 plantas conduzidas no espaçamento de 3 x 1,2 m. O delineamento experimental utilizado foi inteiramente ao acaso, constituído de 2 tratamentos e 12 repetições. As variáveis analisadas foram: florescimento efetivo; densidade de brotação; crescimento dos ramos; desenvolvimento de frutos; qualidade dos frutos (massa, tamanho, coloração, firmeza de polpa, teor de sólidos solúveis); severidade de ferrugem e determinação das concentrações de carboidratos solúveis em raízes e ramos em diversos períodos. De acordo com os dados obtidos pelo presente trabalho, pode-se concluir que para a cultivar Flordaprince, nas condições de Piracicaba-SP, quanto mais intensa for a poda verde realizada em outubro: menor é a concentração de carboidratos solúveis nas raízes no período de dormência; maior é o crescimento de ramos após a sua execução; menor é a fixação de frutos no próximo ciclo; menores são os teores de sólidos solúveis nos frutos. A intensidade da poda verde realizada nas mesmas condições, não interfere: na concentração de carboidratos solúveis em ramos; no florescimento efetivo, densidade de brotação e crescimento de ramos após a poda seca; no desenvolvimento, na massa, na coloração e na firmeza de frutos; na severidade de ferrugem em folhas de pessegueiro. / Sao Paulo State has the major peach production area (Prunus persica (L.) Batsch) for fresh market in Brazil. It is characterized by early-maturing production comparing to southern states of Brazil, with harvest taking place from September to February due to the use of early-season varieties and different production areas in a warmer climate. Peach rust Tranzschelia discolor is a disease affecting peach production in Sao Paulo State and it is favored by warmer and humid conditions especially between September and April. After harvest, practices that delay peach leaf senescence are necessary because this is the period of reserve carbohydrates accumulation for next season. Drastic pruning after harvest is an important rust control method leading to new shoot sprouting and resuming vegetative growth and bud differentiation for next season. This research evaluated the effect of different intensity levels of green pruning after harvest in the development of peach trees and the rust severity. in early-maturing peach cultivar. Experimental work was carried out at "Luiz de Queiroz" campus of University of Sao Paulo, in Piracicaba, Brazil. The following treatments were used: T1 - low pruning (LP) and T2 - drastic pruning (DP), using 345,6 m2 of area with 96 plants in 3 m x 1,2 m spacing. Experimental arrangement used was total randomized plots, with 2 treatments and 12 repetitions. Biometric data collected were: effective blossom, shoot density, stem length, fruit development and quality (fruit weight, diameter, color, pulp firmness and soluble solids concentration), rust severity and total soluble carbohydrate concentrations in roots and stems. In agreement with the data obtained by the present work, it can be ended that for to cultivate Flordaprince, in the conditions of Piracicaba-SP, the more intense it is the green pruning accomplished in october: minor is the concentration of soluble carbohydrates in the roots in the dormancy period; larger is the stem length after his execution; minor is the fixation of fruits in the next cycle; minor are the concentrations of soluble solids in the fruits. The intensity of the green pruning accomplished in the same conditions, it doesn't interfere in the concentration of soluble carbohydrates in stems; in the effective blossom; in the shoot density; in the stem lenght after the dry pruning; in the development; weight, color and the pulp firmness of fruits; in the rust severity in the peaches tree leaves.

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