A busca por embalagens flexíveis rapidamente degradáveis tem sido intensa nos anos mais recentes. Amidos de variadas fontes têm sido avaliados para a produção de filmes, sendo que a maioria destes apresenta boas características mecânicas e de barreira ao oxigênio, entretanto, uma série de limitações é observada com relação às suas características hidrofílicas e permeabilidade ao vapor d´água. O amido de ervilha normalmente apresenta teores mais elevados de amilose, o que pode melhorar a obtenção da rede formadora de filmes. Além disto, as associações amido-goma podem modificar a gelatinização e retrogradação do amido, processos que interferem na formação de filmes. O acréscimo de plastificantes também tem se mostrado de importância para melhorar as propriedades mecânicas dos filmes. Assim, o objetivo do presente trabalho foi avaliar o efeito da adição de goma xantana e de glicerol ao amido de ervilha verde de alto teor de amilose (cv. Utrillo) na elaboração de filmes e em suas características. Soluções filmogênicas (SF) com diferentes teores de amido de ervilha (3, 4 e 5%), de goma xantana (0, 0,05 e 0,1%) e de glicerol (proporção glicerol-amido de 1:5 p/p) foram estudadas. As SF foram obtidas por ebulição (5 min.), seguida de autoclavagem por 1h. a 120°C. Os filmes foram prepa rados segundo a técnica de casting. O aumento da concentração de amido na solução filmogênica aumentou a espessura, fator de ruptura, resistência à perfuração e solubilidade dos filmes em água. O aumento da concentração da goma xantana interferiu apenas nas propriedades associadas à cor dos filmes, aumentando os valores da tonalidade e decrescendo o croma a* e a transparência. O aumento da concentração do glicerol interferiu nas propriedades mecânicas dos filmes, gerando redução dos valores de resistência máxima à tração, tensão na ruptura, resistência à perfuração e fator de ruptura. O plastificante também gerou aumento do alongamento na ruptura, redução da transparência e aumento da espessura e da solubilidade do filme em água. / In the past few years, the attempt to obtain degradable flexible packaging has increased considerably. In this sense, starches obtained from different botanical sources have been evaluated to produce films. Most of these films present good mechanical characteristics and provide a good barrier to oxygen. Nevertheless, some limitations have been observed in relation to their hydrophilic properties and permeability to water vapor. Studies using starch from green peas with high levels of amylose to produce films were not found in the literature. The higher levels of amylose can improve the achievement of the matrix that forms films. In addition, starch-gum associations can modify starch gelatinization and retrogradation, processes which interfere with film formation. The addition of plasticizers has also been considered important to improve the mechanical properties of films. The aim of this study was to evaluate the effect of the addition of xanthan gum and glycerol to the starch of green peas with high content of amylose (cv. Utrillo) in the preparation of films and in their features. Filmogenic solution (FS) with different levels of pea starch (3, 4 and 5%), xanthan gum (0, 0.05 and 0.1%) and glycerol (glycerol-starch ratio of 1:5 p/p) were tested. The FS was obtained by boiling (5 min.), followed by autoclaving for 1h. at 120°C. The films were prepared by casting. The increased concentration of starch in the solution increased the thickness, factor of rupture, puncture force and solubility of films in water. Increasing amounts of xanthan affected only the properties associated with the color of the films, increasing the values of hue angle and decreasing the chroma a* and transparency. The increased concentration of glycerol interfered in the mechanical properties of the films, causing reduction of the maximum values of tensile strength, strain at break, puncture force and factor of rupture. The plasticizer also caused an increase of elongation at break, reduced transparency and increased thickness of the film and the solubility in water.

L'objectif de cette thèse est l'étude par la technologie des puces à ADN, du transcriptome de la bactérie Buchnera aphidicola, qui vit en symbiose avec le puceron du pois Acyrthosiphon pisum. Le génome extrêmement réduit de Buchnera a perdu l'essentiel de ses gènes de régulation, mais conserve les voies de biosynthèse permettant la production des acides aminés essentiels pour son hôte. La première partie de cette thèse concerne le développement du logiciel ROSO, qui permet de déterminer les sondes oligonucléotidiques destinées aux puces. Une interface a été conçue pour son utilisation en ligne (http://pbil.univ-lyon1.fr/roso). Dans une seconde partie, la conception et l'utilisation d'une puce dédiée à Buchnera ont permis d'étudier le transcriptome de la bactérie, lorsque son hôte subit un stress nutritionnel et osmotique. Cette analyse montre que Buchnera est capable de réguler son expression génique et de réorienter son métabolisme, pour répondre à la demande changeante de son hôte.

Les progrès fulgurants de ces dix dernières années réalisés dans les domaines de la microinformatique et de la microfluidique associés au génie génétique (PCR et séquençage) ont permis un changement d'échelle dans la quantité des données acquises au cours d'une même expérience. La transcriptomique est directement issue de ces avancées technologiques. Ce mémoire présenté pour l'obtention d'une Habilitation à Diriger des Recherdes porte sur l'analyse du transcriptome de la bactérie intracellulaire obligatoire des pucerons, Buchnera aphidicola. Dans la première partie, les principales méthodes d'analyses statistiques différentielles et d'intégration des données transcriptomiques sont présentées sous la forme d'une analyse bibliographique. La deuxième partie est consacrée au développement d'outils bioinformatiques : ROSO, un logiciel d'optimisation des sondes oligonucléotidiques, la puce Buchnera et SITRANS, un système d'information pour la gestion et la publication des données d'expression. Enfin, la dernière partie est consacrée à la caractérisation du transcriptome de Buchnera en condition de stress trophique de son hôte, le puceron du pois Acyrthosiphon pisum. La régulation transcriptionnelle chez les bactéries symbiotiques intracellulaires à génome réduit est encore actuellement très mal connue. Cette question sera abordée chez Buchnera tout d'abord au niveau évolutif par l'étude de la relation entre l'expression des gènes et leur organisation dans le génome, puis au niveau fonctionnel, par la caractérisation de la réponse de la bactérie à une diminution de la quantité d'acides aminés essentiels dans le substrat nutritif du puceron, combinée à un stress osmotique.

<p>This investigation addresses how photosynthetic efficiency is affected when pea (Pisum sativum) plants are restricted to a sole nitrogen source (i.e. ammonium or nitrate). The pea plants were watered with different nutrient solutions without NO3- or NH4+ for different time-periods in order to assay for nitrogen content. The soluble ammonium and nitrate content was measured throughout the entire growth period. No major differences were observed in nitrogen content during the starvation period up to 25 days. For technical reasons, cultivation of plants could not be extended beyond this time. The chloroplasts and thylakoids were isolated after 25 days and assayed for chlorophyll contents and photosynthetic activity.</p><p>The outcome of these tests indicates a small but unambiguous decrease in the photosynthesis activity for all treatments, relative the control.</p>

This investigation addresses how photosynthetic efficiency is affected when pea (Pisum sativum) plants are restricted to a sole nitrogen source (i.e. ammonium or nitrate). The pea plants were watered with different nutrient solutions without NO3- or NH4+ for different time-periods in order to assay for nitrogen content. The soluble ammonium and nitrate content was measured throughout the entire growth period. No major differences were observed in nitrogen content during the starvation period up to 25 days. For technical reasons, cultivation of plants could not be extended beyond this time. The chloroplasts and thylakoids were isolated after 25 days and assayed for chlorophyll contents and photosynthetic activity. The outcome of these tests indicates a small but unambiguous decrease in the photosynthesis activity for all treatments, relative the control.

Food allergy is an IgE-mediated immunological disease, which affects almost 4% of the adult population and up to 6% of children. Proteins from milk, egg, peanuts, soybean, wheat, fish and nuts are the main cause of food allergies. A less common allergen is pea protein. The National Food Administration analyses undeclared pea protein and contaminations of pea protein in foods using rocket immunoelectrophoresis and immunodiffusion. For both methods an antiserum against pea protein is needed. The aim of this study has been to characterize a newly developed rabbit-antiserum against pea protein. It is important to know if the antiserum is specific against peas, the detection as well as the quantification limits before it can be taken into use. The results of the study show that the antiserum was not absolutely specific, since it cross-reacted with chickpeas, fenugreek and lenses. However there is an "in-house" established PCR-method that can distinguish between chickpeas, fenugreek and peas and that method can be used as a complement to the rocket immunoelectrophoresis. The PCR-method cannot be used alone because it is not quantitative. Rocket immunoelectro¬phoresis detects 0,003% pea protein with purified IgG-antibodies from the antiserum.

Soilborne plant pathogens are responsible for many of the major crop diseases worldwide. However, plant root tips are generally resistant to pathogen infections. The goal of this dissertation research is to understand the mechanism of this natural resistance by testing the hypothesis that root caps and root border cells control the rhizosphere community through the biological products which they deliver to the soil. Specific objectives of this dissertation project are 1) identifying, isolating, and characterizing the genes important for border cell development and for root exudates delivery, and 2) analyzing the function of extracellular macromolecules in root exudates in root tip-fungal pathogen interaction. The expression of a primary cell wall synthesis gene, PsFut1, encoding Pisum sativum fucosyltransferase, was characterized during border cell production, and the impact of silencing this gene on border cell development was examined. Another gene, BRDgal1, encoding β-galactosidase, was identified and characterized in Pisum sativum during this study. It was shown that this β-galactosidase is specifically produced in and secreted from root border cells. The microarray transcriptional profiling in M. truncatula and mRNA differential display analysis in pea plants were carried out following the induction of border cell production to gain a broader understanding of the genes which potentially influence border cell development. In order to study the commonality of border cell production across different plant species, the expression of rcpme1, the marker gene for border cell production, was compared between the garden pea and a gymnosperm species, the Norway spruce (Picea abies). To accomplish the second objective, the focus of this study was shifted from border cell development to mucilaginous root exudates excreted by border cells and root cap cells. This resulted in a breakthrough in the understanding of the mechanisms of root tip resistance. The presence of extracellular DNA in the root mucilage was discovered and its requirement for root tip resistance to fungal infection was demonstrated. Extracellular proteins in the root mucilage were identified and they were shown to be also required for the root tip resistance to fungal infection. This work provided new insights into understanding plant defense mechanisms.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2008. / Härtill 4 uppsatser.

At the beginning, the plant domestication was probably a non-conscious process. Later, it changed to a targeted process, when the cultural crops were developed from wild species due to human activities. Some crops occurred as a weed of the first cultural species in the past and were selected for individual crops during the domestication. The very beginning of the domestication can be found in neolithic era, when humans chan- ged their way of life from picking & hunting to agriculture & shepherdy. Change of climate after the last ice age was probably one of the reasons. Wild plants as a whole differ from cultural crops in set of domestication characters. Domesticated crops have for example bigger fruits (tomato plant - Solanum lycopersicum L.), contain lower amount of toxic substances (solanine, potato - S. tuberosum L.), natural spreading of seeds and dormancy were inhibited (pea - Pisum L.) etc. Spontaneous releasing of seeds was a big issue already in the past, and is a big issue also now. Afford to avoid this behavior was exerted from the beginning of agriculture. Plants developed various mechanisms of seed spreading into their surroundings for the purposes of species preservation. Legumes developed explosive seed spreading. Shrinking pod valves exert tension on both junctions and once the critical force was reached, the pod suddenly opens. During this action, the pod orientation changes (the tip obliquely upwards) and the seeds are catapulted up to several meters into surroundings. The objective of this work was to narrow mapping interval of the pod shattering ge- ne (Dpo1) in pea (Pisum L.) and focus on evaluation of phenotype of recombinant in- bred lines (RILs). Several RILs formed by crossbreeding of contract parent genotypes of P. elatius were used Steven ex M. Bieb. JI64 × clutural pea P. sativum L. JI92 and reci- procal crossbreeding JI92 × JI64; P. elatius Steven ex M. Bieb. VIR320 × cultural pea P. sativum L. WL1238. Next objective was a comparison anatomical analysis of pod structure in the area of ventral and dorsal junction and endocarp structure.

The diploma thesis deals with the determination of mobile forms of mercury using the technology of diffusion gradient in thin-film. The theoretical part deals with the occurrence of chemical forms of mercury in the environment, mercury effects on plants and methods of determination of mercury's mobile forms. In the practical part, the accumulation of mercury from soils into various organs of garden pea (Pisum sativum L.) was observed. Soil samples were taken in Brno, in streets Opuštěná and Zvonařka. The contents of mercury in soils ranged from 0,32618 +- 0,02493 mg.kg-1 to 0,08382 +- 0,00255 mg.kg-1. Only 0,15 - 0,20 % of the mercury passed from the soil into the soil solution. Only 2,21 to 3,45 % of mercury was available for the soil solution for DGT units and therefore also for the plants. The mercury content in the soil influenced the amount of mercury in the garden pea. The highest concentrations of mercury were detected in the leaves and roots, the lowest concentrations were in the consumed parts of garden pea. The significant correlations were found out between the content of mercury's mobile forms provided by DGT method and the mercury content in roots, leaves and stem of garden pea (correlation coefficients from 0,913 to 0,984). Simulation of acid rains did not demonstrate the raise of mercury's mobility relating to the increase of the acidification of the soil.