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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.
1

Kerndeeling en synapsis bij Spinacia oleracea L.

Stomps, Theodoor Jan, January 1910 (has links)
Thesis (Ph. D.)--Universiteit te Amsterdam, 1910. / Includes bibliographical references.
2

Relações hídricas em espinafre (Spinacia oleracea L.) cultivado com águas salobras sob sistemas hidropônico e solo com e sem cobertura

LEAL, Lucas Yago de Carvalho 09 August 2018 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2018-11-14T12:05:54Z No. of bitstreams: 1 Lucas Yago de Carvalho Leal.pdf: 2074366 bytes, checksum: f35b2c0d597b9e78f6ffe1d859ea7745 (MD5) / Made available in DSpace on 2018-11-14T12:05:54Z (GMT). No. of bitstreams: 1 Lucas Yago de Carvalho Leal.pdf: 2074366 bytes, checksum: f35b2c0d597b9e78f6ffe1d859ea7745 (MD5) Previous issue date: 2018-08-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Due to the water scarcity, common in arid and semiarid regions, the use of brackish water in irrigation is common. However, the inadequate management of these waters, coupled with the climatic characteristics of the region, leads to soil salinization. This process causes a number of deleterious effects that affect the chemical, physical and biological characteristics of soil and, consequently, of crop itself. In general, vegetables are sensitive to abiotic stresses, while at the same time they play an important socioeconomic. Spinach (Spinacia oleracea L.) has high nutritional contents and is a crops that has been growing in the production of family agriculture, either by conventional or hydroponic cultivation. In this work, the objective was to compare the water, physiological and productive aspects of spinach (Spinacia oleracea L.) cultivated with and without soil, arrogating brackish water in the growing process. For this, an experiment was carried out with a randomized block design, with four replications in a 6 x 3 factorial arrangement, with six (6) levels of sodium chloride concentrations in terms of electrical conductivity of 0; 1.5; 3.0; 4,5; 6 and 7 dSm-1 and 3 (three) cultivation systems, two of them in soil, one with plastic mulching and the other without cover, and the third cropping system was represented by the floating type hydroponic model. The potentials of water in the three cropping systems and in spinach were determined, besides associating them with variables of growth and water consumption (discussed in chapter II), as well as parameters of gas exchange, chlorophyll fluorescence and photosynthetic pigments of spinach (Chapter III). The data were submitted to analysis of variance by the F-test (0.05) and when a significant effect was verified, the regression analysis was performed in relation to the different levels of salinity and the analysis of means comparison by the Tukey test at 5 % probability. The main variables analyzed were soil (osmotic), plant potential (leaf and osmotic water potential) and nutrient solution (osmotic potential), leaf area, biomass, gas exchange parameters, chlorophyll fluorescence and photosynthetic pigments. The results showed that there was a reduction in potentials of spinach and soil with an increase in electrical conductivity, being the smallest reductions for the hydroponic system. The three systems showed increased osmotic adjustment with increased salinity of water. The relative water content reduced linearly for the three systems adopted, while there was an increase in leaf succulence due to the reduction of the systems potentials. The hydroponic system showed higher efficiency of water use followed by soil with plastic mulching and soil without cover. There was a reduction of the photosynthetic pigments, as well as the parameters of gas exchange of the spinach due to the increase of the salinity. The chlorophyll a fluorescence only showed a difference between the systems adopted. The potentials of water in the system and spinach is an important tool for monitoring the water status of the crop and the use of techniques such as hydroponics and plastic mulching are important to reduce the effects of the use of brackish water in spinach, in addition to providing greater efficiencies of water use. / Devido à escassez hídrica, comum em regiões de clima árido e semiárido, o uso de águas salobras na irrigação é cada vez mais comum. Entretanto, o manejo inadequado destas águas atrelado as características climáticas da região propicia a salinização do solo. Este processo causa uma série de efeitos deletérios que afetam características químicas, físicas e biológicas do solo e, consequentemente, do próprio cultivo. As hortaliças, de maneira geral, são culturas sensíveis aos estresses abióticos, ao mesmo tempo em que desempenham importante papel socioeconômico. O espinafre (Spinacia oleracea L.) apresenta altos teores nutricionais e é uma das culturas que vem crescendo na produção da agricultura familiar, seja pelo cultivo convencional ou hidropônico. Neste trabalho, objetivou-se comparar aspectos hídricos, fisiológicos e produtivos de espinafre (Spinacia oleracea L.) cultivada com e sem solo arrogando águas salobras no processo de cultivo. Para isso, foi realizado um experimento com delineamento em blocos ao acaso, com quatro repetições em arranjo fatorial 6 x 3, sendo 6 (seis) níveis de concentrações de cloreto de sódio representados em termos de condutividades elétrica de 0; 1,5; 3,0; 4,5; 6,0 e 7,5 dSm-1 e 3 (três) sistemas de cultivo, sendo dois deles em solo, um com cobertura plástica e o outro sem cobertura e o terceiro sistema de cultivo foi representado pelo modelo hidropônico tipo floating. Determinaram-se os potenciais da água nos três sistemas de cultivo e em espinafre, além de associa-los com variáveis de crescimento e consumo de água (abordados no capítulo II), como também, foi analisado parâmetros de trocas gasosas, fluorescência da clorofila e pigmentos fotossintéticos do espinafre (capítulo III). Os dados obtidos foram submetidos a análise de variância pelo teste F (0,05) e quando constatado efeito significativo, realizou-se à análise de regressão em relação aos diferentes níveis de salinidade e à análise de comparação de médias pelo teste de Tukey a 5% de probabilidade. As principais variáveis analisadas foram os potenciais do solo (osmótico), da planta (potencial hídrico foliar e osmótico) e da solução nutritiva (potencial osmótico), além da área foliar, biomassa, parâmetros de trocas gasosas, fluorescência da clorofila e pigmentos fotossintéticos. Os resultados demonstraram que houve redução dos potenciais do espinafre e do solo com aumento da condutividade elétrica, sendo as menores reduções para o sistema hidropônico. Os três sistemas apresentaram aumento do ajustamento osmótico com o aumento da salinidade da água. O Teor Relativo de Água reduziu linearmente para os três sistemas adotados, ao mesmo tempo que houve aumento da suculência foliar em decorrência da redução dos potenciais dos sistemas. O sistema hidropônico apresentou maior eficiência do uso da água seguido pelo solo com cobertura plástica e o solo sem cobertura. Houve redução dos pigmentos fotossintéticos, bem como dos parâmetros de trocas gasosas do espinafre em decorrência do aumento da salinidade. A fluorescência da clorofila a só apresentou diferença entre os sistemas adotados. Os potenciais de água no sistema e no espinafre é uma importante ferramenta para o monitoramento do status hídrico da cultura e o uso de técnicas como hidroponia e cobertura plástica são importantes para redução dos efeitos do uso da água salobra no espinafre, além de propiciarem maiores eficiências do uso da água.
3

Ascophyllm nodosum Extracts Improve Shelf Life and Nutritional Quality of Spinach (Spinacia oleracea L.)

Fan, Di 29 September 2010 (has links)
In order to develop an environmentally friendly seaweed extract treatment which will benefit both pre- and post-harvest qualities of vegetables, the effects of pre-harvest application of the brown algae Ascophyllum nodosum extracts on the nutritional quality and post-harvest storability of spinach (Spinacia oleracea L.) was investigated. Plants treated with A. nodosum extracts accumulated higher concentrations of iron, potassium, total soluble protein, and total phenolics as compared to untreated controls. 1H NMR and LC-MS analysis revealed a roughly 50% enhanced accumulation of the 9 flavonoids identified, which is partially confirmed by the elevated chalcone isomerase activity. A. nodosum extract treatment caused an increase in transcription of the genes related to plant growth, osmolyte accumulation, and antioxidative activities. Post-harvest analysis revealed that A. nodosum extract treatment caused an enhanced storability of spinach leaves in terms of visual quality, weight loss, and senescence. Lipid peroxidation and ascorbate content were correlated with visual quality during storage. Animal experiments using the Caenorhabditis elegans nematode model revealed that spinach extracts prolonged the life span of C. elegans, and A. nodosum extract-enhanced polyphenols exerted improved beneficial effects in C. elegans against oxidative and heat stresses. Taken together, the results suggest that A. nodosum extracts enhance both pre- and post-harvest quality of spinach through stimulation of flavonoid pathways, thus leading to accumulation of flavonoids and promotion of anti-radical capacity in spinach leaves, which may protect the plant tissue against reactive oxygen species and subsequent decay. Furthermore, the increased flavonoid content in spinach exerted beneficial effects in C. elegans against oxidative and heat stresses via different mechanisms.
4

Bioactive compounds in baby spinach (Spinacia oleracea L.) : effects of pre- and postharvest factors /

Bergquist, Sara, January 2006 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
5

Persistencia de Halosulfuron-metil en cultivos de lechuga (Lactuca sativa L.) y espinaca (Spinacia oleracea L.)

Grez González, Javiera Patricia January 2008 (has links)
Memoria para optar al título profesional de Ingeniero Agrónomo Mención Fitotecnia / Durante la temporada agrícola 2007/2008 en el Campus Antumapu de la Facultad de Ciencias Agronómicas de la Universidad de Chile, (32° 40' lat. sur y 70° 32' long. oeste), se realizó un estudio para determinar la persistencia del herbicida halosulfuron-metil para el posterior establecimiento de lechuga (Lactuca sativa L.) y espinaca (Spinacia oleracea L.). El herbicida fue aplicado en dosis de 75 g·ha-1 de ingrediente activo y se utilizaron plantines de lechuga var. capitata cv. Sahara y semillas de espinaca cv. Callas F1. Se realizaron dos ensayos independientes: Ensayo 1: Persistencia de halosulfuron-metil para el posterior establecimiento de lechuga y Ensayo 2: Persistencia de halosulfuron-metil para el posterior establecimiento de espinaca. Para ambos ensayos se establecieron 7 tratamientos que correspondieron al tiempo transcurrido entre la aplicación del herbicida y el establecimiento de cada cultivo, es decir, los tratamientos correspondieron a la plantación de lechuga o siembra de espinaca en suelos tratados 0, 30, 45, 60, 75 y 90 días antes con halosulfuron-metil, más un tratamiento testigo sin la aplicación del herbicida. Para cada ensayo se evaluaron semanalmente la fitotoxicidad visual, altura y número de plantas, días de siembra o transplante a cosecha, peso fresco, rendimiento; mientras que para el ensayo 1 se evaluó adicionalmente el diámetro de lechugas. Según el análisis estadístico realizado, todas estas variables analizadas se vieron afectadas por halosulfuron-metil. En el ensayo 1 la fitotoxicidad fue de carácter temporal, registrándose en algunos tratamientos un aumento de ésta en las primeras evaluaciones. Debido a esto la variable más afectada fue el número de plantas, influyendo directamente en el rendimiento obtenido. En el ensayo 2 la fitotoxicidad fue temporal y en descenso. De igual forma que en la lechuga, el número de plantas fue el parámetro más afectado y el rendimiento del tratamiento testigo resultó ser estadísticamente distinto del resto de los tratamientos. Los resultados y análisis desarrollados permiten concluir que la persistencia de halosulfuron-metil para el establecimiento de lechuga es de 76 días y para el establecimiento de espinaca es superior a los tres meses. / The persistence of halosulfuron-methyl herbicide for the subsequent establishment of lettuce (Lactuca sativa L.) and spinach (Spinacia oleracea L.) was studied during the 2007- 2008 agricultural season at the Antumapu Campus of the College of Agricultural Sciences, University of Chile (32º40’ South lat. And 70º32’ West long.) The herbicide was applied at doses of 75 g/ha active ingredient to soil where lettuce, var. capitata L., cv. Sahara, seedlings were planted and spinach, cv. Callas F1, seeds were sown. Two independent trials were conducted as follows: trial 1, persistence of halosulfuron-methyl for subsequent lettuce establishment; trial 2, persistence of halosulfuron-methyl for subsequent spinach establishment. For both trials seven treatments were established, involving the length of time elapsed between herbicide application and each crop’s establishment, i.e. treatments corresponded to spinach sowing or lettuce planting in soils which had previously (0, 30, 45, 60, 75 and 90 days before) been treated with halosulfuron-methyl, plus a control treatment with no herbicide application. For each trial, weekly evaluations of phytotoxic visual symptoms, plant number and height, days from sowing or transplanting to harvest, fresh weight, and yield were made; for trial 1 lettuce diameter was evaluated as well. According to the statistical analyses carried out, all variables were affected by halosulfuron-methyl. Phytotoxicity in trial 1 was temporary, with an increase being recorded in some treatments in the first evaluations. Because of this, the most affected variable was number of plants, which directly influenced the yield obtained. In trial 2, phytotoxicity was temporary and decreasing. As it occurred with lettuce, the number of plants was the most affected parameter. The yield of the control treatment proved to be statistically different from the rest of treatments. These results allow to conclude that halosulfuron-methyl persistence for establishing a lettuce crop is 76 days while for a spinach crop it is over three months.
6

緑色植物型光化学系II超複合体におけるPsbPタンパク質の相互作用と分子機能

西村, 太志 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(生命科学) / 甲第20525号 / 生博第367号 / 新制||生||48(附属図書館) / 京都大学大学院生命科学研究科統合生命科学専攻 / (主査)教授 佐藤 文彦, 教授 河内 孝之, 教授 福澤 秀哉 / 学位規則第4条第1項該当 / Doctor of Philosophy in Life Sciences / Kyoto University / DFAM
7

Impatiens Necrotic Spot Virus Resistance in Transgenic Impatiens walleriana and Lycopersicon esculentum

Sears, Vicki P. 29 January 2018 (has links)
vegetable crops. Micro-Tom is a model tomato cultivar used for research due to its small size and short time to fruiting. This project evaluated I. walleriana and Micro-Tom transformed with Agrobacterium. The construct contained GFP (green fluorescent protein) and hygromycin antibiotic-resistant selectable markers, and the antisense sequence of open reading frame of INSV nucleocapsid protein (N). The N gene is expected to confer INSV resistance by RNA interference or gene silencing. The presence of transgenes was confirmed by PCR. Transgenic Impatiens was selfed for two generations. Transgenic Micro-Tom was selfed for 4 generations. Spinach was used as an INSV reservoir. Impatiens, spinach and Micro-Tom were mechanically inoculated with INSV and evaluated visually, with assay tests, ELISA testing, and PCR. Spinach was successfully infected with INSV six times of seven attempts. Impatiens and Micro-Tom had no successful inoculations of three and five attempts, respectively. / Master of Science / Impatiens walleriana, also known as impatiens or ‘Bizzy Lizzy,’ is a popular ornamental plant. It has a wide variety of flower colors and grows well in shade. Impatiens necrotic spot virus (INSV) is an incurable virus that causes disfiguring dead spots on plants. Micro-Tom is miniature tomato used for research due to its small size and short time to fruiting. This project tested impatiens and Micro-Tom transgenic plants that had been genetically modified using bacteria. The bacteria had been modified to contain ‘markers’ which allow researchers to confirm the modifications were successful. It also contained a small piece of genetic material from the virus, which was expected to make the plants resistant to the virus by interfering with virus movement and reproduction. These transgenic plants were self-pollinated for multiple generations and tested to confirm the transgene was present. “Wild-type” (not genetically modified) spinach was infected with the virus by hand and infected spinach leaves were used to try to infect impatiens and Micro-Tom. The plants were inspected visually and leaves were tested for presence of the virus. Spinach was successfully infected with INSV six times of seven attempts. Impatiens and Micro-Tom had no successful inoculations of three and five attempts, respectively.

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