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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.
121

Bee pollination of strawberries on different spatial scales – from crop varieties and fields to landscapes

Klatt, Björn Kristian 14 March 2013 (has links)
No description available.
122

Braškių vandens poreikio tyrimai Lietuvos Vidurio zonoje / Strawberry water requirements in Middle Lithuania

Taparauskienė, Laima 09 February 2006 (has links)
Restoration of Lithuanian independence, land reform, radically changed farming structure and strawberry growing potential has conditioned an increase of modern strawberry plantation. Irrigation is a rather important precondition for the commercial cultivation of fruit and berries in Lithuania. The new farm structure requires new, mainly small-scale irrigation systems. Strawberry water consumption and the soil water dynamics during strawberry growing period stated performing pilot research and additional yield which had been got because of the irrigation influence allows to measure optimal irrigation regime of the strawberry based on research. The aim of the work was to investigate dynamics of strawberry evapotranspiration in the Middle Lithuania and in the course of experiments, with respect to development peculiarities and productivity, to determine optimal irrigation regime for the strawberry grown in loamy soils. In the summary is presented strawberry evapotranspiration results maintaining optimal soil moisture conditions with irrigation; analysis of reference evapotranspiration methods; determination of their interaction degree and evaluation of the possibilities to introduce reference evapotranspiration models in calculation of the evapotranspiration of strawberries; quantitative evaluation of the influence of meteorological factors on the amount of the water consumed by strawberries and analysis of strawberry evapotranspiration calculation methods; evaluation of soil... [to full text]
123

The historical archaeology of the Old Farm on Strawberry Hill : a rural estate 1827-1889, Albany, Western Australia

Gardos, Amy January 2004 (has links)
This thesis presents the results of historical archaeological research at the Old Farm on Strawberry Hill in Albany, Western Australia. The site is an important colonial farm in Western Australia’s history; the location for the first farm in Western Australia (1827) and linked to many important individuals in the state’s colonial past. The site is owned and managed by the National Trust of Australia (W.A.) and is registered on both the West Australian, Heritage Council Register of Historical Places and the Australian Heritage Commission’s National Estate. Past historical and cultural biases had created an incomplete interpretation of this site that did not represent all social groups, including indentured servants, convict and Aboriginal labourers and women. The research has provided a holistic site interpretation that identified all social groups living and working on this site in the 1800s by analysing historical documents and archaeological excavated materials. The historical documentary record included both personal and official correspondence, diaries and drawings, as well as two valuable farm log books that documented the day to day events on the farm in the early to mid 1800s. The archaeological excavation was restricted to small area excavations in habitation areas still present on the site or in areas identified from 19th century surveyor maps. Both of these data sources were analysed to identify social and economic relationships, such as gender, status, class and ethnicity so that a comparison could be made between historical and archaeological data and a complementary interpretation created. The research was divided into three main periods of site occupation, firstly by convict gardeners during the government farm period from 1827 to 1832. The Spencer family period from 1833 to 1889, which is further defined by two phases, the six years from their arrival until Richard Spencer’s death in 1839 and the dispersal of the family and the property decline until it was sold in 1889. The third period of occupation by the Bird family was not discussed due to the discontinuation of a farming subsistence that distinguished it from a rural rather than an urban property. This study provides the current heritage managers with an updated interpretation of the site’s past and changing social and economic relationships on site and with the early town of Albany. It is hoped that this interpretation will be used to improve the site’s current representation and becomes the basis for a heritage conservation plan which not only recognises the importance of existing site structures, but also sub surface remains. This thesis also identifies a number of avenues for future research that will further enhance the site’s interpretation.
124

Etudes comparatives de différents processus de séchage de fraise par air chaud, lyophilisation et autovaporisation instantanée : application à la préservation des contenus biologiques / Comparatives studies of different drying process of strawberry hot air drying freeze-drying and swell-drying : application on the biological compounds preservation

Alonzo Macias, Maritza 14 May 2013 (has links)
La présente étude concerne l’évaluation de l’impact du séchage par air chaud (HAD), lyophilisation (FD) et « swell drying » (SD), procédé couplant le séchage par air chaud avec le procédé de Détente Instantanée Contrôlée (DIC), sur les fraises (Fragaria var. Camarosa). Il s’agit de comparer et de contraster les performances des procédés et la qualité du produit fini séché en termes des cinétiques de séchage et de réhydratation, de contenus en molécules bioactives et activité antioxydante, et des paramètres caractéristiques de texture comme croquant et croustillant. Les résultats obtenus ont montré que le procédé de SD comparé aux procédés classiques de séchage et de lyophilisation, réduit d’une façon importante le temps de séchage ainsi que les coûts d’opération. D’autre part, SD conserve la qualité nutritionnelle des fraises en gardant leur contenu en composants bioactifs et en augmentant leur disponibilité. De plus, une corrélation importante entre la capacité antioxydante et le contenu total d’anthocyanes a été établie. D’autre part, les fraises séchées par SD ont montré une très intéressante macro et micro-structure. Les produits ont présenté une haute expansion et une croustillance significative due au phénomène de micro-alvéolation par décompression instantanée par DIC. D’ailleurs, il a été possible de mesurer les caractéristiques instrumentales de croustillance/croquance des échantillons finaux séchés. Grâce à la possibilité de modifier, contrôler et optimiser les paramètres opératoires du procédé DIC, il a été possible d’obtenir un produit du type « snack » croustillant avec une très haute valeur nutritionnelle. / The aim of this study was to evaluate the effect of hot air drying (HAD), freeze-drying (FD) and swell drying (SD), which is a coupling of hot air drying to instant controlled pressure drop, (DIC) on the strawberry (Fragaria var. Camarosa) to compare and to contrast its quality in terms of drying and rehydration kinetics, bioactive compounds and its antioxidant activity, and texture parameters as crunchy and crispy features. The obtained results shown that SD method helped to reduce the drying time leading to a low-cost processing compared with classical hot air drying and freezedrying. SD globally preserved the strawberry’s nutritional value and bioactive compounds, increasing their availability. Moreover, a strong correlation between antioxidant activity and total anthocyanin content was established in SD strawberries. On the other hand, the swell-dried strawberries showed an interesting macro and micro-structure. They presented a high expansion ratios and significant crispness provoked by the micro-alveolation phenomenon induced as consequence of the instant decompression process in the DIC treatment. Moreover, it was possible to instrumentaly measure the crispy/crunchy features of the final dried samples. By assessing such crispy and healthy contents of fruit “snacking”, it was possible to modify, control, and optimize DIC operating parameters. And, it can be designed according to the industrial or consumer needs.
125

Okrasné parkové dřeviny zásobárnou virů čeledi Rhabdoviridae / The ornamental park tree species as a resource of the Rhabdoviridae family viruses

PECKOVÁ, Lucie January 2012 (has links)
Rhabdoviridae family viruses attacking the plant hosts were only described at the angiosperms. In this work, a gymnosperm rhabdoviridae infection was described for the first time ever ? specifically at Ginkgo biloba. Even though there were not observed any kinds of obvious infection symptoms on any of randomly chosen plant samples, through the molecular methods and detection primers the rhabdoviridae infection was proved at six of the plant samples. The acquired nucleotide and amino acid sequences, which were compared with the GenBank sequences, confirm the Rhabdoviridae family viruses occurrence. These given sequences demonstrated a certain analogy with a Strawberry crinkle virus assigned to the genus of Cytorhabdoviruses. The analyses proved a different reciprocal homology among the nucleotide sequences of the individual isolates, and in all likelihood an occurrence of two up to now unknown viruses in the Ginkgo biloba samples was proved for the first time. A definite categorization will be dependent on an acquisition and comparison of other sequences from the isolates genome and also on certain biological characteristics observation.
126

Emisní zátěž při pěstování vybraných plodin / Emission load during growing of selected crops

MRÁČKOVÁ, Jana January 2013 (has links)
The thesis focuses on partial assessment of the life cycle of the strawberry plant (Fragaria), the breeding of which has a long tradition in the Czech Republic. The breeding technologies in conventional and ecological farming systems are compared, in relation to the greenhouse gases emission. The data from agriculture and transportation were accumulated by way of questionnaire survey and expert literature.The objective of this thesis was to assess the impact of individual agrotechnical factors on the pollution of the environment with greenhouse gases emissions in conventional and ecological farming systems, and also to test the hypothesis on whether it is better, from the environmental point of view, to consume locally produced or imported strawberries.The environmental impact was calculated with the SIMAPro software. This tool uses the Ecoinvent databases and enables to create a model of life cycle of the product in question according to the ČSN EN ISO 14040 and ČSN EN ISO 14044 standards. Theinputs and outputs were related to the unit of one hectare and the resulting value was converted as per 1 kg of strawberries. The input included technological operations, amount of fertilisers, and plant protection products; the output of the analysis was the emission load per1 kg of strawberries expressed in the CO2 equivalent.
127

Studies for implementation of Neozygites floridana as control agent of two-spotted spider mite in strawberry / Estudos para implementação de Neozygites floridana como agente de controle do ácaro rajado em morangueiro

Vanessa da Silveira Duarte 28 May 2013 (has links)
Neozygites floridana is an important natural enemy of Tetranychus urticae in many crops, including strawberry. In this crop there has been some changes in the production system from open field to low tunnel. This new system presents benefits to strawberry production, moreover this system increases problems with spider mites and some fungal plant pathogens; consequently increasing the use of pesticides. In order to integrate N. floridana in the management of spider mites in strawberry there are still many important aspects to be revealed on the biology, epizootiology of the fungus and the effect of crop systems on its prevalence in the field. For this, three studies were performed, being the first one about the effect of strawberry production systems (low tunnel and open field) and pesticide application on population dynamics of two-spotted spider mite T. urticae, its natural enemies (N. floridana and predatory mites), and plant diseases, the experiment was performed in Inconfidentes-MG. The population of T. urticae attained the highest level in treatments with chemical control of pest, independently of the crop system, low tunnel or open field. The fungus N. floridana was observed late in both crop seasons, in treatments with and without inoculative releases, and has suggested that it might be a natural occurrence of the fungus. The highest prevalence of the fungus were observed in treatments with high densities of T. urticae. The predatory mites occurred naturally during the two crop seasons, and the most abundant species was Neoseiulus anonymus (Chant) (57.5%). The incidence of fungal plant diseases are greater in the open field than in low tunnel, however it seems that the crop system do not affect the new disease \"vermelhao\". The second study aimed to reveal the abiotic and biotic factors involved in the regulation of resting spores formation in the hosts T. urticae and T. evansi. The Brazilian isolate ESALQ1420 produced a large number of resting spores (51.5%) in T. urticae at a temperature 11 °C, photoperiod of 10L:14D, light intensity of 42-46 (?mol m-2s-1), on non-senescent plants. Small percentages of mites with resting spores (0-5 %) were found for the Norwegian isolate NCRI271/04 under the conditions tested, and very low percentages of resting spores (up to 1%) were observed in T. evansi infected by the Brazilian isolate ESALQ1421.The third study was therefore conducted phylogenetic analysis of isolates of N. floridana and develops efficient real-time PCR-based analysis for detection and quantification of N. floridana propagules from the soil. The phylogenic three showed that Neozygites is a fungal group far from other Entomophthoromycota and that N. floridana present high intra-specific variability. This data indicates that the isolates from different Tetranychus species may be in fact different Neozygites species, not described yet. We developed a real-time PCR probe for detection and quantification of N. floridana in the soil. This molecular probe was successful in quantifying N. floridana at relatively high DNA concentrations seeded into the soil. / Neozygites floridana é um importante inimigo natural de Tetranychus urticae em diversas culturas, incluindo morango. Nesta cultura tem havido uma mudança no sistema de produção, passando de cultivo em campo aberto para túnel baixo. Este novo sistema apresenta benefícios na produção de morango, no entanto pode aumentar problemas com ácaros fitófagos e algumas doenças fúngicas, consequentemente aumentando o uso de agrotóxicos. Para a integração de N. floridana no manejo de ácaros fitófagos em morango, existem ainda muitos aspectos importantes a serem conhecidos sobre a biologia, epizootiologia do fungo e efeito dos sistemas de cultivo sobre a sua prevalência em campo. Para isso três estudos foram realizados, sendo o primeiro estudo sobre o efeito de sistemas de produção de morango (túnel baixo e campo aberto) e da aplicação de agrotóxicos sobre a dinâmica populacional do acaro rajado T. urticae, seus inimigos naturais (N. floridana e ácaros predadores) e doenças de plantas, o experimento foi realizado em Inconfidentes-MG. A população de T. urticae atingiu altos níveis em tratamentos com controle químico de pragas, independente do sistema de cultivo, túnel baixo ou campo aberto. O fungo N. floridana foi observado no final de ambos os ciclos de cultivos, nos tratamentos com e sem liberações inoculativas, sugerindo que houve incidência natural do fungo. As maiores prevalências do fungo foram observadas em tratamentos com altas densidades de T. urticae. Os ácaros predadores ocorreram naturalmente durante os dois ciclos de cultivo, sendo Neoseiulus anonymus (Chant) a espécie mais abundante (57.51%). A incidência de doenças fúngicas foi maior em campo aberto do que em túnel baixo, no entanto parece que o sistema de cultivo não afetou a incidência da nova doença vermelhão. No segundo estudo objetivou-se conhecer os fatores abióticos e bióticos envolvidos na formação de esporos de resistência nos hospedeiros T. urticae e Tetranychus evansi. O isolado brasileiro ESALQ1420 produziu um grande número de esporos de resistência (51.5%) em T. urticae, a uma temperatura de 11 ° C, fotoperíodo de 10F:14E, intensidade de luz de 42-46 (?mol m-2s-1), em plantas senescentes. Pequenas percentagens de ácaros com esporos de resistência (0-5%) foram encontrados para o isolado Norueguês NCRI271/04 sob as condições testadas, e muito baixas percentagens de esporos de resistência (ate 1%) foram observados em T. evansi infectados pelo isolado brasileiro ESALQ1421. O terceiro estudo objetivou analisar filogeneticamente os isolados de Neozygites patogênicos a ácaros, e desenvolver ferramenta utilizando PCR em tempo real para a detecção e quantificação de propágulos de N. floridana a partir do solo. A arvore filogenética mostrou que Neozygites e um grupo de fungos distante dos demais Entomophthoromycota, e que estes fungos apresentaram alta variabilidade intraespecífica entre isolados de N. floridana. Estes resultados indicam que isolados provenientes de diferentes espécies hospedeiras do gênero Tetranychus podem ser de fato diferentes espécies de Neozygites não descritas ainda. Desenvolveu-se uma sonda molecular para detecção e quantificação de N. floridana no solo utilizando PCR em tempo real. Esta sonda foi eficiente na quantificação de N. floridana, em concentrações relativamente altas de DNA inoculado no solo.
128

Estudo de agentes polinizadores em cultura de morango (Fragaria x ananassa Duchesne - Rosaceae) / Pollinators in strawberry crop(Fragaria x ananassa Duchesne - Rosaceae)

Katia Sampaio Malagodi Braga 10 December 2002 (has links)
Os objetivos deste estudo foram: avaliar a fauna de polinizadores potenciais do morangueiro em campos de produçaõ comercial; verificar a contribuição de diversos agentes de polinização na produtividade do morangueiro, conhecendo a biologia floral e reprodutiva dos cultivares mais utilizados para o plantio; testar, em cultivo fechado (estufa), diversas espécies de Meliponini (abelhas sem ferrão)como polinizador do morangueiro, avaliando a sua adaptação ao cultivo e sua efetividade nesta cultura. Os resultados obtidos revelaram que as flores do dos cultivares "Sweet Charlie" e "Oso Grande" necessitam de um polinizador para a produção de frutos sem deformação pois a morfologia de suas flores e o amadurecimento de suas estruturas reprodutivas não favorecem a ocorrência da autopolinização, nem a distribuição homogênea do pólen pelos estigmas da flor, resultando em frutos deformados que não alcançam o seu potencial máximo de desenvolvimento. A abelha jataí (Tetragonisca angustula) adaptou-se bem ás condições do cultivo fechado (estufa) e mostrou-se efetiva na polinização do morangueiro, resultando em frutos mais pesados e em uma porcentagem mais elevada de frutos bem formados. / The aims of this study were: to investigate potencial pollinators of strawberry crops in commercial fields; to verify the contribution of several pollination agents on strawberry productivity, studying the floral and reproductive biology of some commercial cultivars; to evaluate the possibility of the rational use of stingless bees in strawberry pollination inside greenhouses. The results showed that the floral morphology of "Sweet Charlie" and Oso Grande" cultivars and the maturation pattern of their stamens and pistils nor favour the occurrence of self pollination neither the regular pollen distribuction among stigmata, yielding deformed fruits that don´t complete their development. Therefore these cultivars need pollinators to commercial production. Tetragonisca angustula (Apinae, Meliponini)was remarkable for its relatively quick adaptation inside greenhouses and for its effectivity as strawberry pollinator, resulting in heavier berries and high percentage of marketable fruits.
129

Morango processado minimamente e conservado sob refrigeração e atmosfera controlada / Fresh-cut strawberry stored under refrigeration and controlled atmosphere

Moraes, Ingrid Vieira Machado de, 1977- 11 July 2005 (has links)
Orientador: Benedito Carlos Benedetti / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-06T12:39:45Z (GMT). No. of bitstreams: 1 Moraes_IngridVieiraMachadode_M.pdf: 1083227 bytes, checksum: f6970cba937a018276285532776da269 (MD5) Previous issue date: 2005 / Resumo: O morango é uma hortaliça de clima temperado e tem atração peculiar por sua coloração vermelha brilhante, odor característico, textura macia e sabor levemente acidificado. Dada à sua grande demanda para utilização na culinária nacional e internacional, é desejável o desenvolvimento de tecnologia para o seu processamento mínimo. O presente trabalho teve como objetivo avaliar a qualidade físico-química, sensorial e microbiológica de morangos processados minimamente e mantidos sob refrigeração e atmosfera controlada. Morangos da cultivar Oso Grande foram colhidos em campo de produção comercial, localizado no município de Pouso Alegre, MG, e transportados para o Laboratório de Pós-Colheita da Embrapa Agroindústria de Alimentos, localizada no município do Rio de Janeiro, RJ, sendo mantidos por aproximadamente 10 horas em câmara fria a 5ºC e 85% de umidade relativa, até o início do processamento. Após seleção e classificação, os frutos foram processados minimamente retirando-se o cálice e o pedúnculo dos frutos. A sanificação foi feita em água a 5ºC/10 minutos, com 150 µL L-1 de cloro ativo e o enxágüe em água a 5ºC/5 minutos, contendo 5 µL L-1 de cloro ativo. Depois de secos, os morangos foram pesados, acondicionados em bandejas plásticas do tipo polietileno tereftalato (PET) e mantidos sob atmosfera controlada durante 10 dias, a 5ºC e a 10ºC. O controle da atmosfera foi feito em microcâmaras e as seguintes composições atmosféricas foram estabelecidas: AC1 ¿ 3 % O2 + 10 % CO2 (balanço N2), AC2 ¿ 3 % O2 + 15 % CO2 (balanço N2), AA ¿ Atmosfera ambiente (controle). Os frutos foram avaliados nos dias 0, 3 e 7 e 10 quanto à perda de massa, firmeza, pH, acidez titulável, sólidos solúveis, açúcares (sacarose, frutose e glicose), teor de antocianinas totais, cor (valores L e a) e qualidade microbiológica. A análise sensorial foi realizada nos dias 3, 7 e 10 do armazenamento, com a avaliação dos atributos de aparência, textura e sabor. Não houve diferenças significativas entre as temperaturas de armazenamento 5ºC e 10ºC para a maioria das variáveis físico-químicas avaliadas. A atmosfera de armazenamento influenciou significativamente a perda de massa, a firmeza, o teor de frutose, de antocianinas totais. As atmosferas de armazenamento contendo 3% O2 + 10% CO2 e 3% O2 + 15% CO2 foram mais eficientes para a manutenção da firmeza dos frutos minimamente processados, bem como foram mais efetivas no controle da perda de massa que a atmosfera ambiente. Todavia, os frutos MP mantidos nestas atmosferas apresentaram menor teor de antocianinas que os mantidos em atmosfera ambiente, embora não se tenha observado mudanças significativas ao longo do período de armazenamento em nenhum dos tratamentos. A presença de sabores estranhos nos morangos processados minimamente e mantidos sob 3% O2 + 10% CO2 e 3% O2 + 15% CO2, quando avaliados sensorialmente, fez com que o produto fosse rejeitado pelos provadores a partir do 3º dia de armazenamento, quando a aparência ainda era adequada. A temperatura de 5ºC foi mais efetiva que a temperatura de 10ºC na manutenção da aparência, na retenção do sabor característico e na prevenção do surgimento de sabores estranhos. O tempo de armazenamento não afetou os atributos de textura e sabor avaliados sensorialmente, porém afetou todos os atributos de aparência, especialmente no 10º dia a 10ºC. A redução da temperatura de 10ºC para 5ºC e a utilização das atmosferas com 3% O2 + 10% CO2 e 3% O2 + 15% CO2 diminuiu o crescimento de bactérias psicrotróficas e de fungos filamentosos e leveduras, aumentando a vida útil dos morangos processados minimamente / Abstract: Strawberries are a temperate vegetable crop highly appreciated by consumers due to their unique characteristics such as bright red color, soft texture and slightly acidified flavor. Due to their high demand both at national and international level, the development of fresh-cut technology for strawberries is highly desirable. The present work was carried out aiming at evaluating physico-chemical, sensorial and microbiological characteristics of fresh-cut strawberries kept under refrigeration and controlled atmosphere. Strawberries 'Oso Grande¿ were harvested at a commercial field located at Pouso Alegre, MG, and transported to the Postharvest Laboratory at Embrapa Agroindústria de Alimentos, Rio de Janeiro, RJ, and were stored for approximatelly 10 hours in cold rooms at 5ºC and 85% relative humidity until processing. After grading and sizing fruits were minimally processed and the calyx and peduncle were removed. Sanitation was done in a solution of chlorine (150 µL L-1) at 5°C for 10 min. Rinsing was carried in a solution of chlorine of 5 µL L-1 at 5°C for 5 min. After room drying, fruits were weight, placed in plastic trays polyethylene tereftalato type (PET) and kept under controlled atmosphere conditions for 10 days at 5 and 10°C. Atmosphere control was accomplished in micro-chambers where the following atmospheric combinations were established: 3% O2 + 10% CO2 (N2 balance), 3% O2 + 15% CO2 (N2 balance), and Ambient atmosphere (control). Fruits were evaluated at 0, 3, 7 and 10 days for mass loss, firmness, pH, titratable acidity, soluble solids, sugars (sucrose, fructose and glucose), total anthocyanins, color (L-value, a-value), and microbiological quality. Sensory analysis was performed at 3, 7 and 10 days of storage, and appearence, texture and flavor were evaluated. There were no significant differences among most of the variables studied both at 5ºC and 10°C. Storage atmosphere had a significant effect in mass loss, firmness, levels of fructose and total anthocyanins and luminosity at the cut site. Atmospheres with 3% O2 + 10% CO2 and 3% O2 + 15% CO2 were more efficient in firmness maintenance for fresh-cut fruits as well as were more effective to control mass loss at normal atmosphere (air). However, fresh cut fruits kept in these atmospheres showed a lower content of total anthocyanins, although no significant changes were observed throughout the storage period. The presence of off-flavors detected by the taste panel in the fresh-cut strawberries stored under 3% O2 + 10% CO2 and 3% O2 + 15% CO2 made with that the product was rejected by the provers from 3rd day of storage, when the appearance was still adequate. Storage at 5°C was more effective in the maintenance of appearance, flavor retention and in the prevention of off-flavors. Storage length did not affect texture and flavor attributes evaluated by the sensory panel, but affected visual attributes. Temperature reduction from 10ºC to 5°C and the utilization of 3% O2 + 10% CO2 and 3% O2 + 15% CO2 concentrations reduced the growth of psycotrophic bacteria, molds and yeasts, increasing the shelf life of fresh-cut strawberries / Mestrado / Tecnologia Pós-Colheita / Mestre em Engenharia Agrícola
130

Atmosfera controlada na conservação de morango / Controlled atmosphere on the conservation of strawberry

Luis Carlos Cunha Júnior 01 April 2011 (has links)
Os objetivos deste trabalho foram avaliar os efeitos isolados de distintas concentrações de dióxido de carbono (CO2), de oxigênio (O2) e de óxido nitroso (N2O); e também as combinações dos melhores resultados para a conservação de morangos \'Oso Grande\'. Os frutos foram selecionados, resfriados e armazenados a 10 °C em câmaras herméticas, com fluxo contínuo de 150 mL min-1. Os frutos foram avaliados a cada dois dias até se tornarem impróprios para o consumo. Quanto maior as concentrações de CO2 (0,03 %; 10 %; 20 %, 40 % e 80 %) associadas a 20 % de O2 em atmosfera de armazenamento menor foi a incidência de doenças. Os morangos armazenados com 80 % de CO2 foram considerados inadequados para o consumo, por apresentarem teores elevados de acetaldeído (4,9 mg 100g-1) e de etanol (105,3 mg 100g-1). Já as concentrações de 20 % e de 40 % CO2 conservaram os frutos por até oito dias, com manutenção da cor e das características comerciais. As concentrações de O2 (1 %; 3 %; 20 %; 60 %; e 90 %) demonstraram que a atividade respiratória dos morangos foi menor nas atmosferas com 1 % e 3 % de O2. O tratamento com 90 % O2 proporcionou menor incidência de podridões (2,8 %). Os morangos armazenados com 60 e 90 % de O2 mantiveram suas características comerciais por 10 dias. No ensaio com diferentes concentrações de N2O (0 %; 10 %; 30 %; 60 %; e 80 %) associadas a 20 % de O2, observou-se que os frutos com esse gás obtiveram as melhores avaliações de aparência, e reduziu em 36,3 % a respiração dos mesmos após 24 horas de armazenamento, e manteve-se estável até o fim do período. As concentrações de 60 % e de 80 % N2O se mostraram adequadas para a conservação dos morangos, por apresentarem menor ocorrência de doenças e de taxa respiratória, e, portanto, mantendo as características comerciais. Neste experimento foram avaliadas novamente as atmosferas com 0,03 % CO2 + 20 % O2; 80 % N2O + 20 % O2 e 90 % O2; além de avaliar as combinações de 60 % O2 + 40 % CO2 e de 20 % O2 + 20 % CO2 + 60 % N2O. As menores incidências de podridões e as melhores notas de aparência foram nos frutos armazenados com 80 % N2O + 20 % O2 e 20 % O2 + 20 % CO2 + 60 % N2O. Os morangos sob 60 % O2 + 40 % CO2 foram considerados inadequados para o consumo, por apresentarem teores elevados de acetaldeído (54,8 mg 100g-1) e de etanol (42,4 mg 100g-1). Os morangos \'Oso Grande\' a 10 ºC, sob atmosfera controlada com 80 % N2O + 20 % O2; 90 % O2 ou 20 % O2 + 20 % CO2 + 60 % N2O, conservam sua coloração, reduziram a ocorrência de doenças e mantiveram a qualidade comercial por 14 dias. / The aim of this work were to evaluate the isolates effects of different concentrations of carbon dioxide (CO2), oxygen (O2) and nitrous oxide (N2O); and also the combinations of the best results for the conservation of strawberries \'Oso Grande\'. The fruit have been selected, cooled and stored to 10 °C in air tight chambers with continuous flow of 150 ml min-1. The fruits were evaluated every two days to become unfit for consumption. The higher concentrations of CO2 (0,03 %; 10 %; 20 %, 40 % and 80 %) associated with 20 % O2 in the atmosphere of storage, it smaller was the incidence of diseases. The strawberries stored with 80 % of CO2 were considered unsuitable for the consumption on the present high levels of acetaldehyde (4,9 mg 100 g-1) and the ethanol (105,3 mg 100 g-1). Already concentrations of 20 % and 40% of CO2 were conserved the fruit for up to 8 days, with maintenance of the color and the commercial characteristics. The concentrations of O2 (1 %; 3 %; 20 %; 60 %; and 90 %) showed that strawberry respiratory activity was lower in atmospheres with 1 % and 3 % of O2. The treatment with 90 % O2 provided the lower incidence of rotting (2,8 %). The strawberries stored with 60 and 90 % O2 maintained their commercial characteristics for 10 days. In the test with different concentrations of N2O (0 %; 10 %; 30 %; 60 %; and 80 %) associated with 20 % O2, observed that the fruit with this gas obtained the best results of appearance, and the respiratory rate of the fruit reduced in 36,3 % after 24 hours of storage, and maintained stable until the end of the period. The concentrations of 60 % and 80 % of N2O showed appropriate for the conservation of strawberries for presented a lesser occurrence of diseases and of respiratory rate, and therefore maintaining the commercial characteristics. In this experiment were evaluated again the atmospheres with 0,03 % CO2 + 20 % O2; 80 % N2O + 20 % O2 and 90 % O2; in addition to evaluating the combinations of 60 % O2 + 40 % CO2 and 20 % O2 + 20 % CO2 + 60 % N2O. The smallest incidences rotting and best notes of appearance were in the fruit stored with 80 % N2O + 20 % O2 and 20 % O2 + 20 % CO2 + 60 % N2O. The strawberries under atmosphere with 60 % O2 + 40 % CO2 were considered unsuitable for consumption to the showed high levels of acetaldehyde (54,8 mg 100 g-1) and of ethanol (42,4 mg 100 g-1). The strawberries \'Oso Grande\' at 10 ºC, under controlled atmosphere with 80 % N2O + 20 % O2; 90% O2 or 20 % O2 + 20 % CO2 + 60 % N2O maintained their color, reduced the occurrence of diseases and maintained the commercial quality for 14 days.

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