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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.
421

Efeito do consumo de frutas, legumes e verduras na saúde cardiovascular em adolescentes: uma revisão sistemática / Effect of fruit and vegetable consumption on cardiovascular health in adolescents: a systematic review

Collese, Tatiana Sadalla 10 February 2017 (has links)
Introdução: O consumo de frutas, legumes e verduras é pouco frequente entre os adolescentes, e o possível efeito deste consumo na saúde cardiovascular durante esta faixa etária é indefinido. Objetivo: Verificar se existe associação entre o consumo de frutas, legumes e verduras e indicadores de risco cardiovascular em adolescentes (obesidade abdominal, hiperglicemia, hipertrigliceridemia, dislipidemia, hipertensão arterial sistêmica, e síndrome metabólica). Métodos: Registrou-se esta revisão sistemática no PROSPERO (CRD42013004818) para realizar uma revisão sistemática em seis bases de dados eletrônicas (Biomed Central, CINAHL, MEDLINE, PsycINFO, Scopus, Web of Science). Considerou-se o período desde a criação destas bases de dados até sete de Dezembro de 2015 como data mais recente para a atualização das buscas. A estratégia de busca utilizou os seguintes grupos de descritores: faixa etária; frutas, legumes e verduras; indicadores de risco cardiovascular; estudos transversais ou coorte. Os critérios de elegibilidade foram: Artigos em Inglês, Espanhol e Português? estudos originais? amostra composta de adolescentes (dez a 19 anos de idade segundo a organização mundial de saúde); descritores de acordo com os indicadores de risco cardiovascular estabelecidos para adolescentes. Artigos potencialmente elegíveis foram selecionados por dois revisores separadamente. Resultados: Foram identificados 5632 artigos. Após a leitura dos títulos e resumos, 102 artigos potencialmente relevantes permaneceram para a leitura na íntegra. Após seleção, 11 artigos preencheram os critérios de elegibilidade e foram incluídos (dez transversais, uma coorte). As principais razões para a exclusão dos estudos foram classificação da adolescência diferente da preconizada pela Organização Mundial de Saúde, o consumo de frutas, legumes e verduras analisado como parte de um padrão alimentar (por exemplo, juntamente com peixes, laticínios ou cereais), e os indicadores de risco cardiovascular que não foram especificados ou que diferiram das definições estabelecidas. Os artigos avaliaram a ingestão de frutas, legumes e verduras em diversas unidades de medida, utilizando-se questionários de frequência de consumo alimentar (54.5%), recordatório alimentar de 24 horas (27.3%) e registro alimentar (18.2%). Além disso, o consumo de frutas, legumes e verduras foi avaliado separadamente (54.5%), em conjunto (36.4%), apenas legumes e verduras (9.1%), e um estudo incluiu suco de frutas (9.1%). Um terço dos estudos mostraram associações significativas entre o consumo de frutas, legumes e verduras e a pressão arterial sistólica, obesidade abdominal, triglicérides, HDL colesterol e síndrome metabólica. Conclusão: As associações entre o consumo de frutas, legumes e verduras e indicadores de risco cardiovascular em adolescentes são inconsistentes. Isto se deve provavelmente à heterogeneidade nos métodos utilizados para avaliar/classificar o consumo e/ou definir o risco cardiovascular neste grupo etário. Uma vez que os benefícios deste consumo já são bem estabelecidos na saúde cardiovascular de adultos, ainda são necessários estudos adicionais que abordem alta qualidade metodológica para melhor compreender esse fenômeno nos adolescentes / Background: Fruit and vegetable consumption is infrequent among adolescents, and the possible effect of this consumption on cardiovascular health during this age group is undefined. Aim: To investigate the association between fruit and vegetable consumption on cardiovascular risk indicators in adolescents (abdominal obesity, hyperglycemia, hypertriglyceridemia, dyslipidemia, hypertension and metabolic syndrome). Methods: This systematic review was registered in PROSPERO (CRD42013004818), and a systematic review searching electronic databases (Biomed Central, CINAHL, MEDLINE, PsycINFO, Scopus, Web of Science) from inception to December 7, 2015 was conducted. The search strategy used the following sets of descriptors related to: age group; fruits and vegetables; cardiovascular risk indicators; cross-sectional and cohort studies. Eligibility criteria were: Articles in English, Spanish and Portuguese; original studies; sample of adolescents (10-19 year-old according to World Health Organization); descriptors according to the cardiovascular risk indicators. Potentially eligible articles were selected by two reviewers separately. Results: A total of 5632 articles were identified. After reading the titles and abstracts, 102 potentially relevant articles remained for full reviewed. After selection, 11 articles meeting the inclusion criteria were included (10 cross-sectional; 1 cohort). The main reasons for study exclusion were misclassifying adolescence, assessing fruits and vegetables as part of a food pattern (for example, together with fish, dairy, or cereal), and cardiovascular risk indicators that were not specified or that differed from the definitions established. Articles evaluated fruit and vegetable intake in diverse units, using food frequency questionnaires (54.5%), 24-hour-dietary-recalls (27.3%), and food records (18.2%). In addition, fruit and vegetable consumption were assessed separately (54.5%), together (36.4%), or only vegetables (9.1%); and 1 article included fruit juice (9.1%). A third of the studies showed significant inverse associations of fruit and vegetable intake with systolic blood pressure, abdominal obesity, triglycerides, HDL cholesterol, and metabolic syndrome. Conclusion: The associations between fruit and vegetable consumption and adolescent cardiovascular risk indicators are inconsistent. Since the benefits of this consumption are well established in adult cardiovascular health, further studies are necessary, addressing high methodological quality to better understand this phenomenon in adolescents
422

Fatores associados aos gastos com alimentos marcadores de dieta saudável e não saudável: o papel da preocupação com a saúde / Factors related to expenses with indicators to healthy and unhealthy diets: the role of health concern

Murino, Glaucia Barrizzelli 27 February 2015 (has links)
Objetivo: Este trabalho Investigou a associação dos gastos com frutas, legumes e verduras (marcadores de dieta saudável) e com carnes e carnes processadas (marcadores de dieta não saudável) com fatores socioeconômicos, demográficos e com preocupação com a saúde. Métodos: Trata-se de um estudo de análise transversal que utiliza dados secundários da Pesquisa de Orçamento Familiar (POF) 2008-2009 do IBGE, e investiga os fatores associados aos gastos com alimentos marcadores ou não de dieta saudável por meio de um modelo Tobit de regressão múltipla, determinando-se os efeitos marginais das variáveis explicativas. Assim, foi investigada a influência da preocupação com a saúde e de variáveis socioeconômicas e demográficas sobre gastos com dois grupos de alimentos: (a) frutas, legumes e verduras e (b) carnes e carnes processadas. Resultados: O presente estudo mostrou que os gastos com alimentos marcadores de dieta saudável (FLV) e com alimentos marcadores de dieta não saudável (CCP) estão associados a variáveis econômicas e sócio demográficas e à preocupação com a saúde, conforme a expectativa baseada na literatura sobre o tema. Há, no entanto, uma única exceção: o efeito dos gastos preventivos com a saúde sobre os gastos com FLV. Tal achado merece investigação adicional, em termos da constituição da variável proxy da preocupação com a saúde, adotada neste estudo. / Objective: This paper strives to identify how the expenses with fruits and vegetables (healthy diet markers), meats and processed meats (unhealthy diets markers) are influenced by the presence of health seeking behavior, socioeconomic and regional factors. Methods: A cross-sectional analysis study based on secondary data from \"Household Budget Survey 2008-2009,\" IBGE, using the multiple regression TOBIT model. The analysis was about how one\'s concern with health influences the expenses with two food groups: (a) fruits and vegetables and (b) meats and processed meats. Health seeking behavior and socioeconomic characteristics were included as variables. The marginal effect of each explanatory variable over the probability of expenses with the food groups studied was determined. Results: The study shows that the expenses with fruits and vegetables (healthy diet markers) and meats and processed meats (unhealthy diet markers) are related to economical, socio demographic variables and to the concern for health, just as expected based on previous studies. There is, however, one exception: the effect of preventive expenses with health over the expenses with fruits and vegetables. Such finding requires additional investigation regarding the constitution of the concern for health\'s proxy variable.
423

Avaliação da ação de antimicrobianos naturais no controle de Salmonella Enteritidis em salada de legumes com maionese / Evaluation of the activity of natural antimicrobials on the control of Salmonella Enteritidis in mayonnaise-based legume salad

Silva, Janine Passos Lima da 20 August 2007 (has links)
Salmonella Enteritidis (SE) é um enteropatógeno de grande preocupação para indústria de alimentos, principalmente de produtos que não podem ser submetidos a tratamento térmico, como as saladas à base de maionese, freqüentemente envolvidas em surtos de salmonelose. O uso de antimicrobianos naturais nesses produtos pode ser um método alternativo para o controle de SE. Assim, o objetivo deste trabalho foi avaliar o efeito antimicrobiano de óleo essencial de orégano, EDTA e nisina individualmente e a combinação de nisina com EDTA e nisina com óleo essencial de orégano no controle da multiplicação SE em salada de legumes com maionese. A atividade inibitória foi inicialmente avaliada in vitro e posteriormente em salada preparada com legumes, experimentalmente contaminados com SE, misturados à maionese, na concentração de 103 UFC/g, e armazenados em refrigeração (8°C) e em temperatura ambiente (30°C). Os resultados da avaliação in vitro indicaram que o OEO usado individualmente tem melhor efeito antimicrobiano contra SE do que quando empregado em combinação com nisina. Nem a nisina nem o EDTA, quando testados isoladamente ou combinados apresentaram efeito sobre SE. Na salada de legumes com maionese preparada artesanalmente, a presença de 0,2% de OEO resultou em redução na contagem de SE, constituindo-se em uma barreira adicional para a multiplicação do patógeno nesse produto. A análise sensorial da salada de legumes com maionese contendo 0,2% de OEO indicou que houve 95% de aceitação do aroma, 93% de aceitação do sabor e 74% de intenção de compra. A análise sensorial da maionese contendo 0,5% ou 1% de OEO indicou a inviabilidade de se aumentar a concentração do OEO na maionese como alternativa para melhorar o efeito antimicrobiano. / Salmonella Enteritidis (SE) is an enteropathogen relevant for the food industry, especially in foods that do not require heat treatment before consumption such as salads prepared with mayonnaise, frequently associated to outbreaks of salmonellosis. Natural antimicrobials can be used as an alternative procedure to control SE in these foods. The aim of the present study was to evaluate the effect of origanum essential oil (OEO), nisin and EDTA, used individually and in combination, on the growth of SE in mayonnaise and in mayonnaise-based legume salad. The inhibitory activity was evaluated in vitro, in home made mayonnaise and in mayonnaise-based legume salad experimentally contaminated with SE at 103 CFU/g, stored under refrigeration (8°C) and at room temperature (30°C). The results of the in vitro tests indicated that a better antimicrobial effect of OEO on SE was achieved when OEO was used individually than when used combined with nisin or EDTA. Nor nisin nor EDTA, used individually, presented any effect against SE. The presence of OEO in mayonnaise did not add any additional effect to the antimicrobial activity of the intrinsec parameters in this food. In mayonnaise-based legume salad, 0.2% of OEO caused a reduction in the counts of SE, and was an additional hurdle for the growth of the pathogen in this product. The sensorial testing of mayonnaise-based legume salad containing 0.2% OEO indicated an acceptance of 95% for the aroma and 93% for the taste and 74% of purchasing intention. The sensorial testing of mayonnaise containing 0.5% or 1% OEO indicated that the increase in the content of OEO to increase the antimicrobial activity is not feasible.
424

Yield, nutritive value and effects on soil fertility of forage grasses and legumes cultivated as ley pastures in the Borgou region of Benin/Production, valeur alimentaire et effets sur la fertilité des sols de graminées et de légumineuses fourragères cultivées comme jachère fourragère dans la region du Borgou au Bénin

Adjolohoun, Sébastien 26 May 2008 (has links)
Summary In the Sudanian zone of West Africa like in the Borgou region of Benin, agricultural and livestock systems face more and more difficulties linked to climatic changes, the decrease in soil fertility and the degradation of natural grasslands. This leads to a decrease in agricultural yields and feeding resources for livestock. On another hand, the socio-economical conditions of the small-holders dont allow them to invest in mineral fertilisers to remedy to soil fertility decrease. The introduction of ley pastures in crop rotations may be an affordable solution to increase available feeds for livestock and to improve soil fertility. The first part of this work reviews the potentialities of various local and exotic grasses and legumes which could be cultivated in the Borgou region. The choice of these species take into consideration the pedo-climatic conditions of the region, their aptitude for production, their nutritive value and their contribution to soil fertility. In the second and third parts of the thesis, the results of experimental 3-year ley pastures using 4 grasses (Panicum maximum Jacq cv. C1, Andropogon gayanus Kunth with broad leaves, A. gayanus with narrow limbs and Pennisetum purpureum Schumach.) and 6 légumineuses (Aeschynomene histrix Poir, Stylosanthes fruticosa (Retz.) Alson, Centrosema pubescens Benth., Mucuna pruriens (L.) DC. var. utilis Wall. Ex Wight) Baker ex Burck, Cajanus cajan (L.) Millsp. and Leucaena leucocephala (Lam.) De Wit) and exploited without any supply in mineral fertilisers are described concerning their yields and nutritive values. The grasses productions varied between 2 200 and 4 600 forage units (UF, in French unites fourragères)/ha/year and between 170 and 450 kg digestible crude protein/ha/year according to species and years (P<0.05). The forage legumes produced between 1 400 and 4 800 kg dry matter (DM)/ha/year according to species and years (P<0.05) with crude protein contents ranging from 16 to 27 %. Except Na and Zn, the combination of these two forage groups can satisfy the ruminant needs in macro and micro-minerals. The fourth part of the manuscript presents a soil-fertility balance under the different ley pastures after 3 years of exploitation. At the end of this study, it appears that in the experimental conditions (cut-and-carry system without fertilisers) Andropogon gayanus with broad leaves and the ligneous legume species Cajanus cajan and Leucaena leucocephala ensure the highest DM yields and are the less exhausting for soil fertility due to deeper root systems enabling to bring up to the surface mineral elements from deep layers / Résumé Dans la région soudanienne de lAfrique de lOuest comme dans le Borgou au Bénin, les systèmes de production agricole et délevage connaissent de plus en plus de difficultés liées aux aléas climatiques, à lappauvrissement rapide des sols et à la dégradation des végétations naturelles. Il en résulte une baisse des rendements agricoles et des ressources alimentaires pour le bétail. Par ailleurs, les conditions socio-économiques des producteurs limitent leurs possibilités dachat d'engrais en vue de remédier à la baisse de fertilité des sols. Dans ce contexte lintroduction de jachères fourragères dans les rotations culturales constitue une solution pour augmenter les disponibilités alimentaires destinées au bétail et enrichir le sol. La première partie de ce travail présente un inventaire de graminées et de légumineuses locales ou exotiques qui peuvent être implantées dans le Borgou. Le choix de ces espèces tient compte des conditions pédo-climatiques de la région, de leur aptitude à la production, de leur valeur alimentaire et de leur contribution à la fertilité des sols. Dans les deuxième et troisième parties de la thèse, les résultats de jachères expérimentales de trois ans comprenant 4 graminées (Panicum maximum Jacq var. C1, Andropogon gayanus Kunth à larges feuilles, A. gayanus à fines feuilles et Pennisetum purpureum Schumach.) et 6 légumineuses (Aeschynomene histrix Poir, Stylosanthes fruticosa (Retz.) Alson, Centrosema pubescens Benth., Mucuna pruriens (L.) DC. var. utilis Wall. Ex Wight) Baker ex Burck, Cajanus cajan (L.) Millsp. et Leucaena leucocephala (Lam.) De Wit) et exploitées sans apports de fumure minérale sont décrits en ce qui concerne leurs rendements et leurs valeurs alimentaires. Les productions des graminées ont varié entre 2 200 et 4 600 unités fourragères/ha/an et 170 à 450 kg de protéines brutes digestibles/ha/an selon les espèces et les années (P<0,05). Les légumineuses ont produit entre 1 400 et 4 800 kg de matière sèche/ha/an selon les espèces et les années (P<0,05), avec des teneurs en protéines variant entre 16 et 27 %. A lexception du Na et du Zn, lutilisation combinée des fourrages de ces espèces peut satisfaire les besoins en minéraux et oligo-éléments des ruminants. La quatrième partie du manuscrit présente un bilan de fertilité des sols sous ces différentes cultures après 3 années de jachère. Au terme de cette étude, il apparaît que dans les conditions expérimentales (affouragement en vert sans fumure minérale) la graminée Andropogon gayanus à larges feuilles et les légumineuses arbustives Cajanus cajan et Leucaena leucocephala sont les plus productives et les moins épuisantes pour le sol, eu égard à leur enracinement profond, capable de ramener des éléments minéraux en surface.
425

COMPOSIZIONE NUTRIZIONALE DI LEGUMINOSE TRADIZIONALI PER L'ALIMENTAZIONE DEI RUMINANTI / Nutritional composition of traditional grain legumes in ruminant feeding.

PRIMI, RICCARDO 22 April 2010 (has links)
L’alimentazione proteica risulta di fondamentale importanza per l’ottimizzazione della produttività e per il benessere degli animali di interesse zootecnico. L’identificazione di fonti vegetali alternative e/o complementari a quelle attualmente utilizzate (soia in primis) nel razionamento degli animali si rende necessaria per motivi economici, ambientali e legislativi, cercando di evitare, tuttavia, penalizzazioni sull’appetibilità della razione e sulla risposta produttiva. La ricerca condotta ha riguardato lo studio della composizione nutrizionale di semi di cece (Cicer arietinum) e lupino azzurro (Lupinus angustifolius), con approfondimenti sul contenuto di composti nutrizionalmente attivi e/o antinutrizionali, la valutazione della fermentescibilità ruminale mediante tecniche in vitro, anche alla luce di possibili interazioni genetiche (varietà e linee genetiche) e colturali (epoca e densità di semina). I risultati ottenuti hanno permesso di comprendere eventuali limiti di utilizzo di tali leguminose per l’alimentazione degli animali, in particolar modo dei ruminanti, e di attribuire le fonti di variabilità per la massimizzazione produttiva e qualitativa. / Ruminants protein nutrition is an essential item for optimizing the productivity and welfare of animals. The identification of pulses sources as alternative or complementary to those currently used (primarily soya) in the ration of ruminants is necessary for economic, environmental and legislative reasons, trying to avoid, however, penalties on palatability and productive response. The research focused on the study of the nutritional composition of seeds of chickpea (Cicer arietinum) and blue lupine (Lupinus angustifolius), with insights on the content of nutritionally active compounds and / or antinutritionals, the evaluation of the ruminal fermentability using in vitro techniques, also considering possible genetic interactions (varieties and genetic lines) and farming practices (time and density of sowing). The results of the present study suggest that these pulses could be a potentially good feedstuff contributing at the same time to the energy and protein balance of animal diet. Moreover, the presence of active compounds like tannins at levels that should not be regarded as anti-nutritional, can be useful in ruminant feeding due to the moderating activities exerted by those compounds toward the ruminal degradation of proteins.
426

Influence of residual flucarbazone-sodium on inoculation success measured by growth parameters, nitrogen fixation, and nodule occupancy of field pea

Niina, Kuni 22 September 2008
Herbicides have become a key component in modern agricultural production. Meanwhile, there is a concern that some herbicides persist past the growing season of the treated crop, and negatively influence the production of the subsequently planted crops. Amongst various herbicides used in western Canada, acetohydroxyacid synthase (AHAS)-inhibiting herbicides warrant special attention given their residual properties and acute plant toxicity at low concentrations in soil. Soil residual AHAS inhibitors have the potential to influence both leguminous host plants and their bacterial symbiotic partners; consequently, the use of an AHAS inhibitor in a given year can negatively influence the inoculation success and grain yield of legumes cropped in the following year. <p>The present thesis project focused on one of the AHAS inhibiting herbicides (flucarbazone) and studied its potential for carryover injury and negative influence on the success of inoculation in field pea. A series of growth chamber and field experiments were conducted to test the following null hypothesis: the presence of residual flucarbazone in soil does not affect nodulation of field pea by inoculum rhizobia. <p>A growth chamber experiment clearly demonstrated the susceptibility of field pea to the presence of flucarbazone in soil where the lowest concentration of flucarbazone amendment (5 ìg kg1) significantly reduced the crop growth. In contrast, a field study failed to reveal any negative effects of flucarbazone use on crop growth and N2 fixation. <p>It was concluded that if the weather and soil conditions favour decomposition of flucarbazone as described in the present study, flucarbazone applied at the recommended field rate will not persist into the following season at high enough concentrations to negatively influence field pea growth, grain yields, and inoculation success. To ensure safety of rotational crops, it is important to strictly adhere to the herbicide application guidelines. Additionally, producers are cautioned to be particularly aware of the environmental and soil conditions that may reduce the rate of herbicide degradation.
427

Influence of residual flucarbazone-sodium on inoculation success measured by growth parameters, nitrogen fixation, and nodule occupancy of field pea

Niina, Kuni 22 September 2008 (has links)
Herbicides have become a key component in modern agricultural production. Meanwhile, there is a concern that some herbicides persist past the growing season of the treated crop, and negatively influence the production of the subsequently planted crops. Amongst various herbicides used in western Canada, acetohydroxyacid synthase (AHAS)-inhibiting herbicides warrant special attention given their residual properties and acute plant toxicity at low concentrations in soil. Soil residual AHAS inhibitors have the potential to influence both leguminous host plants and their bacterial symbiotic partners; consequently, the use of an AHAS inhibitor in a given year can negatively influence the inoculation success and grain yield of legumes cropped in the following year. <p>The present thesis project focused on one of the AHAS inhibiting herbicides (flucarbazone) and studied its potential for carryover injury and negative influence on the success of inoculation in field pea. A series of growth chamber and field experiments were conducted to test the following null hypothesis: the presence of residual flucarbazone in soil does not affect nodulation of field pea by inoculum rhizobia. <p>A growth chamber experiment clearly demonstrated the susceptibility of field pea to the presence of flucarbazone in soil where the lowest concentration of flucarbazone amendment (5 ìg kg1) significantly reduced the crop growth. In contrast, a field study failed to reveal any negative effects of flucarbazone use on crop growth and N2 fixation. <p>It was concluded that if the weather and soil conditions favour decomposition of flucarbazone as described in the present study, flucarbazone applied at the recommended field rate will not persist into the following season at high enough concentrations to negatively influence field pea growth, grain yields, and inoculation success. To ensure safety of rotational crops, it is important to strictly adhere to the herbicide application guidelines. Additionally, producers are cautioned to be particularly aware of the environmental and soil conditions that may reduce the rate of herbicide degradation.
428

Die Bedeutung der CO2-Fixierung von Leguminosenknöllchen für ihre Aktivität und Effizienz / The importance of nodule CO2 fixation for their activity and efficiency

Fischinger, Stephanie A. 28 May 2009 (has links)
No description available.
429

Performance of underutilized forage legumes as an alternative to Trifolium repens under drought stress: yield, water utilization and nutritive value

Küchenmeister, Kai 07 May 2013 (has links)
Grünland mit hoher Produktivität und Futterqualität bildet die Grundlage der Wiederkäuerernährung. In Grünlandbeständen mit ausbleibender oder geringer Stickstoffdüngung sind Leguminosen unerlässlich für Produktivität und Futterqualität, was auf die Fähigkeit von Leguminosen Luftstickstoff zu binden zurückzuführen ist. Gegenwärtig ist Trifolium repens L. eine der wichtigsten Futterleguminosen im Grünland der gemäßigten Zonen Europas. Es ist allerdings bekannt, dass T. repens eine gute Wasserversorgung benötigt, um einen hohen Ertrag zu erzielen. Verringerte Niederschlagsmengen in der Vegetationsperiode, die unter Klimawandelbedingungen vorausgesagt werden, könnten somit die Ertragsleistung von T. repens verringern. In Zukunft steigt dadurch möglicherweise auch die Bedeutung anderer Futterleguminosen, die besser an trockenere Bedingungen angepasst sind und somit als Alternative für T. repens dienen könnten. Da die Kenntnisse über das agronomische Potenzial solcher möglichen alternativen Leguminosen begrenzt sind, haben wir in dieser Studie fünf vielversprechende und wahrscheinlich besser an Trockenheit angepasste Leguminosen untersucht. Für unsere Versuche haben wir Lotus corniculatus L., L. uliginosus Schkuhr, Medicago lupulina L., M. falcate L. und Onobrychis viciifolia Scop. ausgewählt. In einem ersten Schritt wurde das agronomische Potenzial der Leguminosen im Hinblick auf Etablierung und frühe Ertragsentwicklung mit nicht limitierter Wasserversorgung getestet. Weiterhin wurden der Ertrag und die Ertragsstabilität sowie die Wassernutzung der alternativen Leguminosen bei temporärer Trockenheit untersucht und mit der von T. repens verglichen. Der Einfluss von Trockenstress auf wichtige Futterwert bestimmende Inhaltsstoffe der Leguminosen (Rohprotein, neutrale Detergenzienfasern, saure Detergenzienfasen und wasserlösliche Kohlenhydrate) war überdies Gegenstand der Betrachtungen. Um die oben genannten Parameter zu untersuchen, wurde von 2009 (Einsaatjahr) bis 2011 ein Experiment in Großgefäßen in einer Vegetationshalle durchgeführt. In diesem Versuch wurden alle Leguminosen sowohl in Monokultur als auch in einer praxisüblichen Mischung mit Lolium perenne L. angesät. Im Versuchszeitraum folgten die klimatischen Bedingungen in der Vegetationshalle einem normalen jahreszeitlichen Verlauf, der Frost im Winter und höhere Temperaturen im Sommer umfasste. Der für den Versuch notwendige Trockenstress wurde in drei Aufwüchsen innerhalb von zwei Jahren durch temporären Bewässerungsstopp erzeugt. Dabei wurde im Frühjahr 2010 (April/Mai) ein moderater und im Sommer 2010 (Juli/August) sowie im Frühjahr 2011 (April/Mai) je ein starker Trockenstress induziert. Mit Ausnahme von M. falcata, welches eine verzögerte Anfangsentwicklung zeigte, waren die Keimung und die Etablierung von allen alternativen Leguminosen vergleichbar mit der von T. repens. Die Ertragsleistung von M. lupulina und L. corniculatus in Monokultur war ähnlich hoch wie die von T. repens. In Mischung zeigten beide alternativen Leguminosen zwar Potenzial, aber die Ertragsleistungen waren dennoch geringer als die der T. repens/L. perenne Mischung. In unserem Versuch führte Trockenstress zu verringertem Ertrag und er beeinflusste auch die agronomische Wassernutzungseffizienz (Verhältnis von Ertrag zu Wasserverbrauch). Ausschlaggebend waren dabei die Stärke und die Dauer des Trockenstresses. Besonders starker, aber auch bereits moderater Trockenstress führten bei T. repens zu erheblichen Ertragsverlusten von bis zu 56%. Demgegenüber zeigten vor allem M. lupulina, aber auch L. corniculatus und M. falcata lediglich marginale Ertragsverluste bei moderatem Trockenstress und meist geringere Ertragsverluste als T. repens bei starkem Stress. Die agronomische Wassernutzungseffizienz war bei moderatem Stress verhältnismäßig stabil, wohingegen starker Stress im Vergleich zur Kontrolle meist zu einer geringeren agronomischen Wassernutzungseffizienz führte. Sowohl unter Kontroll- als auch unter Stressbedingungen zeigte speziell M. lupulina in Monokultur eine ähnliche oder sogar eine höhere agronomische Wassernutzugseffizienz als T. repens. Zudem war die agronomische Wassernutzungseffizienz der Mischungen mit M. lupulina, L. corniculatus und M. falcata weniger negativ von starkem Trockenstress betroffen als die Mischung mit T. repens. Dies bestätigte zum einen die Trockenheitsempfindlichkeit von T. repens und zum anderen die bessere Anpassung der alternativen Leguminosen an trockenere Bedingungen. Wir beobachteten, dass eine Änderung in der Stickstofffixierungsleistung der Leguminosen eine gute Erklärungsgröße für Änderungen des Ertrags und der agronomischen Wassernutzungseffizienz darstellt. Hohe Stickstofffixierungsleistung geht dabei meist mit höherem Ertrag und höherer agronomischer Wassernutzungseffizienz einher. Die intrinsische Wassernutzungseffizienz (Verhältnis von assimiliertem CO2 und stomatärer Leitfähigkeit), gemessen als 13C, war ein schlechterer Indikator für die agronomische Wassernutzungseffizienz: Obwohl die intrinsische Wassernutzungseffizienz unter starkem Trockenstress zunahm, sank die agronomische Wassernutzungseffizienz meist ab. Dennoch besitzt die Erhöhung der intrinsischen Wassernutzungseffizienz ein gewisses Potenzial als Anpassung an trockenere Bedingungen Der Trockenstresseffekt auf die Futterqualität war in unserer Studie generell deutlich geringer als der Effekt auf den Ertrag. Besonders moderater Stress hatte wenig Einfluss auf die Futterqualität, während sich die Effekte bei starkem Stress verstärkten. Starker Trockenstress führte meist zu einer Verringerung des Rohprotein- und Fasergehalts (neutrale und saure Detergenzienfasern), wohingegen sich der Gehalt an wasserlöslichen Kohlenhydraten erhöhte. Dies könnte ein Hinweis darauf sein, dass sich die Futterqualität bei Trockenstress sogar verbessert. Nichtsdestotrotz hatten in unserem Versuch die Leguminosenart und die Einsaat als Monokultur oder Mischung einen größeren Einfluss auf die Futterqualität als der Trockenstress. Der Einfluss von Trockenstress auf die Futterqualität ist deshalb bei der Wahl einer geeigneten Futterleguminose weniger von Bedeutung als andere agronomische Eigenschaften. Zusammenfassend ist zu sagen, dass besonders M. lupulina und in geringerem Maße auch L. corniculatus und M. falcata Potenzial als Alternative für T. repens bei Trockenstress zeigen. Nach ausreichender Etablierungszeit entwickeln sich besonders M. lupulina aber auch L. corniculatus und M. falcata stabiler und können sogar höhere Erträge als T. repens bei Trockenstress produzieren. Bezüglich der Futterqualität sind oben genannte alternative Leguminosen ebenfalls vergleichbar mit T. repens.
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Hodnocení semenářských vlastností hrachoru lučního a vikve ptačí a jejich uplatnění v trvalých travních porostech. / The evaluation of seed properties of Lathyrus pratensis and Vicia cracca and their employment in permanent grasslands.

KRATOCHVÍLOVÁ, Eva January 2015 (has links)
The theme of the thesis are climbing legumes meadow vetchling (Lathyrus pratensis) and tufted vetch (Vicia cracca). The literature search defines watched kinds of legumes and their occurence in permanent grassland. There is summarized seed growing of legumes because of its problematic production. Legumes are valuable components of grassland especially thanks to fixation of nitrogen and high capacity of proteins. The practical part is focused on observation of floristic compilation of watched locations for three years. Particular locations were compared from the point of view of changes in land management and weather. Pods and seeds of observed kinds were collected and evaluated in single years. Experiments of seed's field germination were done after different period from picking and in case of various treatment.

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