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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

Qualifica??o da severidade da requeima em tomateiro por escalas diagram?ticas e suas correla??es com a fluoresc?ncia da clorofolifa A e ac?mulo de biomassa e nutrientes / Quantification of tomato late blight by diagrammatic grading keys and their correlations with chlorophyll A and biomass and nutrients accumulation

COSTA, Evandro Silva Pereira 21 September 2009 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-02-09T19:14:10Z No. of bitstreams: 1 2009 - Evandro Silva Pereira Costa.pdf: 2009437 bytes, checksum: cf64a3e8f7e3e004841a52c65f4c6626 (MD5) / Made available in DSpace on 2017-02-09T19:14:10Z (GMT). No. of bitstreams: 1 2009 - Evandro Silva Pereira Costa.pdf: 2009437 bytes, checksum: cf64a3e8f7e3e004841a52c65f4c6626 (MD5) Previous issue date: 2009-09-21 / CNPq / Defining methods of quantification of tomato late blight, caused by Phytophthora infestans, is important to many researches about strategies of management of the disease. The aim of this present study was to assess and to validate the diagrammatic grading keys - Simplified, James-modified and Broad - and to determinate the possible correlations between the measures of severity and plants? physiological and nutritional state and biomass accumulation. Two simultaneous experiments were carried out: one in greenhouse and the other in field conditions. Two cultivars were studied in greenhouses, Super Sweet and ?Perinha ?gua Branca?, a resistant and a susceptible to late blight genotypes, respectively. The plants were inoculated or not with a sporangia suspension, and submitted to ten evaluations: 1, 2, 3, 4, 6, 7, 9, 10, 17 and 24 days after inoculation. The avaliations were performed in the fifth oldest leaf, and eighth and eleventh leaves, by visual estimation of severity, using three diagrammatic grading keys, Simplified, Broad and James-modified, but also measuring photosynthetic potential (Fv/Fm), by chlorophyll ?a? fluorescence emission. In field conditions, four cultivars were evaluated ? ?Perinha ?gua Branca?, Super Sweet, Santa Clara and Carmen F1. Periodically, late blight severity was quantified using the same three grading keys in leaves of different plant parts, at 51, 62, 74, 94 and 102 days after transplant (DAT). At the day following each severity disease evaluation, one plant was harvested per plot to measure the accumulation of biomass and macronutrients of different plant organs. Fruit yield was determined by summing fruits harvested between 68 and 114 DAT. In greenhouse conditions, the estimative of late blight severity with the three diagrammatic grading keys proved to be adequate to the disease?s quantification, enabling the discrimination between inoculation effects and differences between the cultivars in four and in nine days after inoculation, respectively, which were confirmed by measures of the photosynthetic potential of the leaves. In field conditions, the diagrammatic grading keys Simplified and Broad were more adequate to tomato late blight quantification. Quantifications in the youngest leaves, in the medium and superior third part of the plant, were the most representative of the disease progress and also discriminated the cultivars regarding disease resistance. Negative correlations were observed between severity, estimated with the three grading keys considering the whole plant and its medium third part, and leaf dry mass and leaf concentrations of K and P. The cultivar ?Perinha ?gua Branca? showed the lowest stem and leaf dry mass at the beginning of plant evaluations, and also late fruit yield, but had the higher stem and leaf mass and at the end of the experiment. The cultivar Perinha ?gua Branca and the hybrid Carmen F1 had higher commercial fruit yield. Based in the results, it is recommended the use of Simplified diagrammatic grading key and evaluations in the medium or superior tomato third to quantify the late blight disease. / A defini??o de m?todos de quantifica??o da requeima no tomateiro, causada por Phytophthora infestans, ? importante para v?rias pesquisas sobre estrat?gias de manejo da doen?a. Esse trabalho teve como objetivo aferir e validar as escalas diagram?ticas, Simplificada, James-modificada e Detalhada e determinar as poss?veis correla??es entre as medidas de severidade e o estado fisiol?gico e nutricional da planta e o ac?mulo de biomassa. Realizaram-se dois experimentos simult?neos, um sob condi??es de ambiente protegido e o outro sob condi??es de campo. Em casa de vegeta??o, utilizaram-se duas cultivares de tomate cereja, ?Perinha ?gua Branca? e Super Sweet, suscet?vel e resistente ? requeima, respectivamente. As plantas foram inoculadas ou n?o com suspens?o de espor?ngios de P. infestans e em seguida, avaliadas aos 1, 2, 3, 4, 6, 7, 9, 10, 17 e 24 dias ap?s a inocula??o. As avalia??es foram feitas na quinta, oitava e d?cima primeira folha, contadas do ?pice para a base, usando as tr?s escalas acima citadas e medi??es do potencial fotossint?tico (Fv/Fm) pela emiss?o da clorofila ?a?. No campo, utilizaram-se quatro cultivares, ?Perinha ?gua Branca?, Super Sweet, Santa Clara e Carmen F1. Periodicamente, quantificou-se a severidade da requeima utilizando-se as mesmas escalas acima citadas em folhas de diferentes partes da planta, aos 51, 62, 74, 94 e 102 dias ap?s o transplante (DAT). No dia seguinte a cada avalia??o de severidade, foi coletada uma planta por parcela para mensurar o ac?mulo de biomassa e de macronutrientes nos diferentes ?rg?os da planta. A produ??o de frutos foi determinada pelo somat?rio das colheitas realizadas entre 68 e 114 DAT. Em condi??es de casa de vegeta??o, a estimativa da severidade da requeima com as tr?s escalas se mostrou adequada para quantifica??o da doen?a tendo permitido discriminar efeito de inocula??o e diferen?as entre as cultivares aos quatro e nove dias ap?s a inocula??o, respectivamente, que foram confirmadas pelas medidas do potencial fotossint?tico das folhas. Em condi??es de campo, as escalas Simplificada e Detalhada, foram mais adequadas para a quantifica??o da requeima do tomateiro. Quantifica??es feitas nas folhas mais jovens, no ter?o m?dio e superior da planta, foram as que melhor representaram o progresso da doen?a e discriminaram as cultivares quanto a resist?ncia ? doen?a. Observaram-se correla??es negativas entre a severidade, estimada com as tr?s escalas, considerando a planta inteira e o ter?o m?dio, e a massa seca de folhas e os teores foliares de K e P nas quatro cultivares. A cultivar ?Perinha ?gua Branca? apresentou menor massa seca de caule e de folha no in?cio das avalia??es e produ??o de frutos mais tardia, por?m ao final do ciclo destacou-se pela maior massa seca de caule e de folha. A cultivar ?Perinha ?gua Branca? e o h?brido Carmen F1 apresentaram maior produ??o de frutos comerciais. Com base nos resultados pode-se recomendar o uso da escala simplificada e avalia??es no te?o m?dio ou superior do tomateiro para quantifica??o da requeima.
2

Crescimento e produtividade de gr?os do feijoeiro comum sob inocula??o com Rhizobium e aduba??o nitrogenada / Growth and grain yield of common bean under inoculation with Rhizobium and nitrogen fertilization

Barros, Rodrigo Luiz Neves 11 October 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-12T13:51:57Z No. of bitstreams: 1 2016 - Rodrigo Luiz Neves Barros.pdf: 1569971 bytes, checksum: bebc280a379491b5d376031d5427175e (MD5) / Made available in DSpace on 2017-05-12T13:51:57Z (GMT). No. of bitstreams: 1 2016 - Rodrigo Luiz Neves Barros.pdf: 1569971 bytes, checksum: bebc280a379491b5d376031d5427175e (MD5) Previous issue date: 2016-10-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The average productivity of common bean (Phaseolus vulgaris L.) in Brazil is one of the lowest in the world. Alternatives that can increase yield in a sustainable manner should be preconized, such as reducing the use of nitrogen fertilizers through the adoption of biological nitrogen fixation. Therefore, the objective of this study was to evaluate the influence of rhizobia inoculation and sowing nitrogen fertilization on growth and common bean yield (Phaseolus vulgaris L.). Four experiments were conducted in the field, at the Experimental Station of the Department of Crop Science at the Federal Rural University of Rio de Janeiro, Serop?dica, Brazil. So that each experiment was repeated twice in the same growing season. The experiments were conducted in the dry season and rainy the years 2013 and 2014, In a soil classified as Kanhapudalf. For both experiments, we used the common bean cultivar Carioca, indeterminate growth and high yield potential. In the first year of cultivation in the dry season and rainy the experiments were composed of three treatments: only fertilized with 20 kg N ha-1 at sowing and with 40 kg N ha-1 at 25 DAE (A); only inoculated with Rhizobium at sowing and fertilized with 40 kg N ha-1 at 25 DAE (I+N); and inoculated and fertilized with 20 kg N ha-1 at sowing and with 40 kg N ha-1 at 25 DAE (IA); and an additional treatment only inoculated with Rhizobium with no N fertilization at any phase (I-N), only evaluated in the second year of both growing seasons. The experimental design used was in randomized blocks, with four replications in both years. Each plot consisted of 6 rows of 5 m spaced 0,5 m apart. At pollination, it was evaluated the number of nodules (NN), nodules dry weight (MSN), shoot dry weight (MSPA) and root dry weight (MSR). However, was observed the highest NN and MSN in treatments without nitrogen fertilization at sowing in both years. Also, it was determinate the leaf soluble proteins content (TPSF) in four developmental stages vegetative, pollination, flowering and grain filling), with higher values for the TPSF in the treatment IA flowering stage. Moreover, for the growth analysis, three plants were collected on the second line of each side of the plot, weekly from 14 DAE until physiological maturation. At physiological maturation all the plants of the two central rows were collected from each plot to evaluate the crop yield components: number of pods per plant (NV), number of grains per pod (NGV), 100 grain matter (MS100G) and grain yield (PG). As for the production of components, there was a significant difference only for PG, with IA producing the highest PG in both years. Therefore, based on these results, it can be concluded that the inoculation with Rhizobium may replace the nitrogen fertilization (20 kg ha-1) at planting without yield loss, however, the nitrogen fertilization (20 kg ha-1) combined with inoculation with Rhizobium at sowing partly inhibit the root nodulation of the common bean plants and increased its total dry weight and grain yield, in both season. However, more studies are needed to recommend these agronomic practices / A produtividade m?dia de feij?o comum (Phaseolus vulgaris L.) no Brasil ? uma das mais baixas do mundo. Alternativas que possam aumentar a produtividade de forma sustent?vel devem ser preconizadas, tais como a redu??o do uso de fertilizantes nitrogenados pela ado??o da fixa??o biol?gica de nitrog?nio (FBN). Assim, o objetivo deste estudo foi avaliar a influ?ncia da inocula??o de riz?bios e, ou da aduba??o nitrogenada de semeadura no crescimento e produtividade do feijoeiro comum. Foram instalados quatro experimentos no campo experimental do Departamento de Fitotecnia da Universidade Federal Rural do Rio de Janeiro, Serop?dica, Brasil, de modo que cada experimento fosse repetido duas vezes na mesma ?poca de cultivo. Os experimentos foram instalados nas ?pocas da seca e das ?guas dos anos de 2013 e 2014, em um solo classificado como Argissolo Vermelho Amarelo. Para ambos os experimentos, foi utilizado o cultivar de feijoeiro comum Carioca, de crescimento indeterminado e alto potencial produtivo. No primeiro ano de cultivo das ?pocas da seca e das ?guas os experimentos foram compostos por tr?s tratamentos: apenas adubado com 20 kg N ha-1 na semeadura e 40 kg N ha-1 aos 25 dias ap?s a emerg?ncia (DAE) (A), inoculado com Rhizobium e adubado com 40 kg N ha-1 aos 25 DAE (I+N), inoculado com Rhizobium e adubado com 20 kg N ha-1 na semeadura e 40 kg N ha-1 aos 25 DAE (IA) e um tratamento adicional somente inoculado com Rhizobium sem aduba??o nitrogenada em nenhum est?dio (I-N), apenas avaliado no segundo ano de ambas as ?pocas de cultivo. O delineamento experimental utilizado foi em blocos ao acaso, com quatro repeti??es em ambos os anos. Cada parcela foi constitu?da por 6 linhas de 5 m, espa?adas de 0,5 m de dist?ncia. No est?dio de poliniza??o, avaliou-se o n?mero de n?dulos (NN), massa seca de n?dulos (MSN), massa seca de parte a?rea (MSPA) e massa seca raiz (MSR), sendo observado o maior NN e MSN nos tratamentos que n?o receberam aduba??o nitrogenada na semeadura em ambos os anos. Tamb?m foram realizadas coletas de tecido foliar para determina??o do teor de prote?nas sol?veis (TPSF) em quatro est?dios de desenvolvimento (vegetativo, poliniza??o, florescimento pleno e enchimento de gr?os), com valores mais elevados para o TPSF no tratamento IA no est?dio de florescimento. Al?m disso, para an?lise de crescimento, foram coletadas tr?s plantas por parcela, semanalmente dos 14 DAE at? a matura??o fisiol?gica. Na matura??o fisiol?gica foram coletadas todas as plantas das duas linhas centrais de cada parcela, desprezando-se o meio metro final de cada extremidade, para avaliar os componentes de produ??o: n?mero de vagens por planta (NV), n?mero de gr?os por vagem (NGV), massa seca de 100 gr?os (MS100G) e produtividade de gr?os (PG). Quanto aos componentes de produ??o, ocorreu diferen?a significativa apenas para PG, com o tratamento IA apresentando rendimentos mais elevados em ambos os anos. Portanto, segundo os resultados obtidos, a inocula??o de riz?bios pode substituir a aduba??o nitrogenada com 20 kg N ha-1 na semeadura sem perda de produtividade. Al?m disso, a inocula??o com riz?bios, acrescida da aduba??o com 20 kg N ha-1 na semeadura, inibiu parcialmente a nodula??o e propiciou acr?scimo de produtividade em ambas as ?pocas. No entanto, mais estudos s?o necess?rios para recomenda??o dessas pr?ticas agron?micas.
3

Crescimento, composição química e desempenho fisiológico de sementes de trigo submetido a regulador de crescimento / Growth, chemical composition and physiological performance of wheat seeds subjected to growth regulator

Koch, Felipe 28 September 2015 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-04-07T12:30:41Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_felipe_koch.pdf: 799099 bytes, checksum: 5d61cb7ae229b25b533d3f35001c2acc (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-12T18:07:39Z (GMT) No. of bitstreams: 2 dissertacao_felipe_koch.pdf: 799099 bytes, checksum: 5d61cb7ae229b25b533d3f35001c2acc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-12T18:09:51Z (GMT) No. of bitstreams: 2 dissertacao_felipe_koch.pdf: 799099 bytes, checksum: 5d61cb7ae229b25b533d3f35001c2acc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-04-12T18:10:04Z (GMT). No. of bitstreams: 2 dissertacao_felipe_koch.pdf: 799099 bytes, checksum: 5d61cb7ae229b25b533d3f35001c2acc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-09-28 / Sem bolsa / Este trabalho teve por objetivo avaliar o crescimento de plantas de trigo submetidas a aplicação de regulador de crescimento vegetal e adubação para altos rendimentos, assim como, a composição química e a qualidade fisiológica de sementes produzidas. A cultivar utilizada foi a OR Topázio e o regulador de crescimento foi o trinexapac-ethyl, aplicado via foliar. No capítulo I, o experimento foi conduzido em casa de vegetação e o delineamento experimental foi o inteiramente casualisado, em esquema fatorial 5x8 (cinco doses e oito épocas de coleta) com quatro repetições. Foram avaliados a matéria seca total, a taxa de produção de matéria seca, as taxas de crescimento relativo e assimilatória liquida, a razão de área e massa foliar, o índice de área foliar. Foi determinada a eficiência de conversão da energia solar, a partição de assimilados, o índice de colheita, a altura das plantas, a emergência e o índice de velocidade de emergência de plântulas. No capítulo II, o experimento foi conduzido em delineamento experimental inteiramente casualisado com cinco tratamentos e quatro repetições, sendo avaliados a germinação e primeira contagem de germinação, índice de velocidade de germinação, matéria seca de plântulas, condutividade elétrica e envelhecimento acelerado. No capítulo I, a alocação de matéria seca total, a taxa de crescimento relativo, a altura de plantas e o índice de colheita foram reduzidos, com intensidade variável, conforme a dose do regulador de crescimento. A taxa assimilatória líquida foi reduzida em plantas submetidas a doses de 400, 600 e 800 mL ha-1, a razão de massa e de área foliar foram superiores quando utilizadas as doses de 400 e 800 mL ha-1. A emergência e índice de velocidade de emergência não foram afetados pela ação do regulador de crescimento. No capítulo II, a primeira contagem de germinação aumentou até a maior dose. A condutividade elétrica após três horas de embebição foi reduzida, a partir da dose de 600 mL ha-1. Os teores de amido aumentaram até a dose de 448 mL ha-1; o de aminoácidos até a dose 243 mL ha-1 e os teores de proteína até a dose de 417 mL ha-1. Houve redução no teor de açúcares solúveis totais ao aumentar a dose do regulador. Portanto, plantas submetidas à aplicação do trinexapac-ethyl apresentam respostas diferenciais no crescimento e partição de assimilados, menor índice de colheita e altura de plantas. Já, as sementes possuem maior vigor e teores de amido, proteína e aminoácidos, contudo, menor teor de açúcares solúveis totais. / This work aimed to evaluate the growth of wheat plants subjected to the application of growth regulator and fertilization for high yields, as well as, chemical composition and physiological quality of seeds produced. The variety used was OR Topázio and the growth regulator was trinexapac-ethyl, via leaf application. On chapter I, the experiment was performed on greenhouse and the experimental design was completely randomized, factorial 5x8 (five doses and eight harvest dates) with four repetitions. Total dry matter, dry matter production rate, relative growth and net assimilation rates, leaf mass ratio, leaf area ratio and leaf area index were evaluated. The conversion efficiency of solar energy, assimilate partitioning, harvest index, plant height, seedling emergence and speed of emergence index were determined. On chapter II, the experiment was performed under completely randomized experimental design using five treatments and four repetitions, being evaluated germination and first count of germination, speed of germination index, seedling dry matter, electrical conductivity and accelerated aging. On chapter I, total dry matter allocation, relative growth rate, plant height and harvest index were reduced, with variable intensity, according to the growth regulator dose. The net assimilation rate was reduced in plants subjected to 400, 600 e 800 mL ha-1; leaf mass ratio and leaf area ratio were superior when doses of 400 and 800 mL ha-1 were used. The seedling emergence and the speed of emergence index were not affected by the action of the growth regulator. On chapter II, germination and first count of germination increased until the higher dose. Electrical conductivity after three hours of imbibition was reduced starting from the dose of 600 mL ha-1. The starch content increased until the dose of 448 mL ha-1; the amino acids up to the dose of 243 mL ha-1 and the protein content to the dose of 417 mL ha-1. There was a decrease on total soluble sugars content with the increase of growth regulator dose. Therefore, plants subject to the application of trinexapac-ethyl feature differential responses on growth and assimilate partitioning, lower harvest index and plant height. Seeds produced by these plants possess higher germination, vigor expression and starch, protein and amino acids contents, however, lower content of total soluble sugars.

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