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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.
111

Avaliação de novas progênies F6 de sorgo sacarino promissoras para a produção de etanol na Zona da Mata de Pernambuco / Evaluation of new F6 progenies promising sweet sorghum for ethanol production in the forest zone of Pernambuco

OLIVEIRA, Jonathas Rafael Moura de 03 February 2014 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-11-03T12:55:19Z No. of bitstreams: 1 Jonathas Rafael Moura de Oliveira.pdf: 1914760 bytes, checksum: 7b129e821da38e2d66a5ac9fc492da19 (MD5) / Made available in DSpace on 2016-11-03T12:55:19Z (GMT). No. of bitstreams: 1 Jonathas Rafael Moura de Oliveira.pdf: 1914760 bytes, checksum: 7b129e821da38e2d66a5ac9fc492da19 (MD5) Previous issue date: 2014-02-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Currently sweet sorghum (Sorghum bicolor (L.) Moench) has become very important for the energy sector and sugarcane in Brazil, which is constantly seeking alternatives to increase agricultural and industrial yields, especially in the off season of cane sugar, decreasing the idle time and production costs. It is a rustic agricultural species, with good adaptation to environmental stresses, such as those found in the Northeast, with features similar to stalks of sugarcane juice rich in fermentable sugars, and can be used to produce ethanol in the same facility used by the cane sugar. The culture is totally mechanized (by planting seeds, and harvesting), high productivity of green biomass (60-80 t ha-1), with high yields of ethanol (3000-6000 l.ha-1), bagasse usable as a source of energy (steam and electricity cogeneration industrialization). The present study was designed to indicate the most suitable for a probable launch as a variety to be grown in the Zona da Mata, Region of the State of Pernambuco, Northeast, Brazil genotypes. For this purpose, an experiment was carried out from February to June 2014 in the experimental field at the Pernambuco Agricultural Institute Enterprise - IPA, in Vitória de Santo Antão, Pernambuco. The study consisted of 65 progenies that are the result of segregation F6 a cross between two varieties (IPA467-4-2 X IPA 2502), where the first strain was used as male parent and the second as the female parent, were obtained in Vitória Santo Antão - PE in 2010, tested in Caruaru - PE in 2011 and retested in Vitória de Santo Antão - PE in 2013, more than 15 witnesses were commercial varieties in the region, including these two parental strains. The experiment was designed in randomized blocks, consisting of 80 plots and 3 replications, where each portion had dimensions of 6.0 x 0.8 m, with a total area of 4.80 m2 and is considered an area of 3.20 m² (0 , 8 x 4m), eliminating the first meter of each boundary. Variables according to the production characteristics presented in the field were analyzed: average height of plant (AMP); Days to flowering (FL); Total production of green matter (PMV); Production Shed (PCL) and Percentage of thatch to produce total green matter (% CL). Besides the agroindustrial features: Production of total dry matter (PMS); Percentage of total dry matter (% MST); Production Shed (PCL); Harvesting Brix (Brix); Extraction efficiency of broth (EEC) and theoretical Ethanol (ET). Means were compared by Scott - Knott test at 5% level of probability, genetic correlations being conducted to complement the study of these variables. / Atualmente o sorgo sacarino (Sorghum bicolor (L.) Moench) apresenta-se muito importante para o setor sucroalcooleiro e energético do Brasil, que vem buscando constantemente alternativas para aumentar rendimentos agrícolas e industriais, principalmente na entressafra da cana-de-açúcar, diminuindo o tempo ocioso e os custos de produção. É uma espécie agrícola rústica, com boa adaptação a estresses ambientais, tais como os encontrados na Região Nordeste, apresenta colmos com caldo semelhante ao da cana, rico em açúcares fermentescíveis, e pode servir para a produção de etanol na mesma instalação utilizada pela cana-de-açúcar. A cultura é totalmente mecanizável (plantio por sementes, tratos culturais e colheita), alta produtividade de biomassa verde (60 a 80 t.ha-1), com altos rendimentos de etanol (3.000 a 6.000 l.ha-1), com bagaço utilizável como fonte de energia (vapor para industrialização e cogeração de eletricidade). O presente trabalho teve como objetivo avaliar o potencial de novas progênies F6 de sorgo de duplo propósito (grão e forragem, incluindo colmo seco e sacarino), visando definição de aptidão e uso. Para tanto, foi conduzido um experimento nos meses de fevereiro a junho de 2014, no campo experimental no Instituto Agronômico de Pernambuco – IPA, no município de Vitória de Santo Antão-PE. O estudo foi composto por 65 progênies que são resultado da segregação F6 do cruzamento entre duas variedades (IPA 467-4-2 X IPA 2502), onde a primeira variedade foi utilizada como parental masculino e a segunda como parental feminino, sendo obtidas em Vitória de Santo Antão – PE em 2010, testadas em Caruaru – PE em 2011 e novamente testadas em Vitória de Santo Antão – PE em 2013, mais 15 testemunhas que foram variedades comerciais na região, incluindo nestas as duas variedades parentais. O experimento foi delineado em blocos casualizados, composto por 80 parcelas e 3 repetições, onde cada parcela teve dimensões de 6,0 x 0,8m, com 4,80m2 de área total, sendo considerada uma área útil de 3,20 m² (0,8 x 4m), eliminando o primeiro metro de cada bordadura. As variáveis foram analisadas de acordo com as características de produção apresentada em campo: Altura média de planta (AMP); Dias até o florescimento (FL); Produção de matéria verde total (PMV); produção de colmo (PCL) e Porcentagem de colmo na produção de matéria verde total (%CL). Além das características agroindustriais: Produção de matéria seca total (PMS); Porcentagem de matéria seca total (%MST); Produção de colmo (PCL); Brix na colheita (BRIX); Eficiência de extração de caldo (EEC) e Etanol teórico (ET). As médias foram comparadas pelo teste de Scott - Knott em nível de 5% de probabilidade, sendo realizada a correlação genotípica para complementar o estudo destas variáveis.
112

Resistência de cultivares de batata (Solanum tuberosum) à sarna comum (Streptomyces spp.) e mecanismo de ação da fitotoxina taxtomina A em sorgo (Sorghum bicolor ): aspectos bioquímicos e ultraestruturais / Resistance of potato cultivars (Solanum tuberosum) to common scabies (Streptomyces spp.) and action mechanism of the phytotoxin thaxtomin A in sorghum (Sorghum bicolor): biochemical and ultrastructural aspects

Ely Oliveira Garcia 01 August 2008 (has links)
O gênero Streptomyces constitui-se em um grupo diferenciado de procariotos fitopatogênicos, por serem morfologicamente similares aos fungos e produzirem diversos importantes metabólitos secundários. A sarna comum da batata é principal doença causada pelo gênero. O principal agente causal da doença, Streptomyces scabies, produz fitotoxinas denominadas concanamicinas, porém, não foi comprovada a importância da produção das mesmas na agressividade dos isolados de S. scabies. Dessa forma, neste trabalho procurouse avaliar a reação dos cultivares mais plantados no Brasil a isolados de S. scabies exibindo diferentes níveis de produção de concanamicinas. O nível de produção de concanamicinas A e B de dez isolados de Streptomyces spp. foi avaliado por cromatografia líquida de alta pressão (HPLC) e dois isolados (produtor de alto nível da toxina; baixo produtor) foram selecionados e utilizados na avaliação da resistência de seis cultivares de batata em casa de vegetação. Vasos contendo o substrato esterilizado receberam a suspensão de esporos bacterianos junto com os tubérculos sadios no momento do plantio e após quatro meses, a severidade da doença foi avaliada. Os resultados demonstraram aumento na agressividade do isolado produtor de elevadas quantidades de concanamicinas apenas sobre os cultivares Mondial, Monalisa e Asterix. Por sua vez, os resultados da avaliação do nível de resistência ao patógeno demonstraram que os cultivares Monalisa, Ágata, Asterix e Cupido são suscetíveis e os cultivares Atlantic e Mondial mostraram-se resistentes aos dois isolados de Streptomyces spp. avaliados. Por outro lado, a fitotoxina taxtomina A é a toxina mais frequentemente produzida pelas espécies fitopatogênicas de Streptomyces spp. O estudo do mecanismo de ação desta fitotoxina poderá auxiliar no entendimento de sua contribuição no desenvolvimento da doença. A taxtomina A é uma fitotoxina não específica e causa efeitos semelhantes em plantas de diferentes famílias botânicas. Desta forma, modificações citológicas, ultraestruturais e bioquímicas induzidas pela taxtomina A foram analisadas em plântulas de sorgo. Os tecidos foram tratados com taxtomina A e avaliados após sete dias do tratamento. Observou-se desorganização em todas as células dos tecidos tratados com a taxtomina A. A membrana plasmática das células do mesofilo foliar foi retraída e destacada da parede celular em diversos pontos. Entretanto, o plasmalema não pareceu rompido. O efeito sobre a permeabilidade seletiva da membrana plasmática também foi avaliado bioquimicamente, onde foi observado aumentos na saída de eletrólitos. Os cloroplastos apresentaram deformações na superfície e perda de turgidez. Estas deformações provavelmente contribuíram para a redução do teor de clorofilas A e B. As plântulas também apresentaram elevado acúmulo de fitoalexinas do tipo deoxiantocianidinas. Desta forma, conclui-se que a taxtomina A age principalmente sobre a membrana plasmática e organelas membranosas. Em contrapartida, o acúmulo de fitoalexinas evidencia que concentrações mínimas desta toxina podem ser exploradas como eliciador da resposta de defesa em plantas. / The genus Streptomyces is a different prokaryote phytopathogen group, being morphologically similar to fungi and able to produce several important secondary metabolites. The potato common scabies is the main plant disease caused by the members of the genus. The main causal agent of the plant disease, Streptomyces scabies, is able to produce the phytoxins concanamycins. However, the importance of these toxins in the aggressiveness of S. scabies strains was not proven. This research aimed to evaluate the reaction of main potato cultivars used in Brazil to Streptomyces spp. strains, exhibiting different levels of concanamycins production. The toxin production by several strains was quantified by high performance liquid chromatography (HPLC) and two strains (higher and lower producers) were chosen and used for resistance evaluation of six potato cultivars under greenhouse. Pots containing sterile substratum received a suspension of bacterial spores and the healthy seed tubers at the same time. After four months, the level of disease was evaluated and the results showed increasing in aggressiveness for the higher concanamycins producer only in the Mondial, Monalisa and Asterix cultivars. For the two strains, the cultivars Atlantic and Mondial were resistant and the cultivars Monalisa, Cupido, Ágata and Asterix were susceptible. On the other hand, the thaxtomin A is the main phytotoxin of plant pathogenic Streptomyces spp. Therefore, the study of the thaxtomin A action mechanism is important to explain its contribution to disease development. The thaxtomin A is not a specific toxin and causes similar effect in several plants of different botanical families. Thus, the cytological, ultrastructural and biochemical modifications induced by thaxtomin A were evaluated in sorghum seedlings. Leaf tissues of seedlings were treated with high levels of thaxtomin A and evaluated 7 days after treatment. Cytological disorganization was observed in all treated cells. The plasmma membrane of the cells of immature leaves was detached from the wall in several places. However, plasmmalema did not seem degraded. The chloroplasts had showed significant deformations in the surface and volume reduction. Theses changes in chloroplasts probably contributed for the reduction of chlorophylls A and B levels. The sorghum seedlings also showed high phytoalexin accumulation (deoxiantocianydins) in response to thaxtomin A treatment. Thus, the thaxtomin A acts mainly on plasmma membrane and membranous organelles, causing plasmolises, cell disorganization, deformations in chloroplasts and chlorophyll reduction in sorghum seedlings. Finally, the accumulation of phytoalexins in response to thaxtomin A treatment points out it potential to induce resistance in plants.
113

Genomic and proteomic analysis of drought tolerance in Sorghum (Sorghum bicolor (L.) Moench)

Woldesemayat, Adunga,Abdi January 2014 (has links)
Philosophiae Doctor - PhD / Drought is the most complex phenomenon that remained to be a potential and historic challenge to human welfare. It affects plant productivity by eliciting perturbations related to a pathway that controls a normal, functionally intact biological process of the plant. Sorghum (Sorghum bicolor (L.) Moench), a drought adapted model cereal grass is a potential target in the modem agricultural research towards understanding the molecular and cellular basis of drought tolerance. This study reports on the genomic and proteomic findings of drought tolerance in sorghum combining the results from in silica and experimental analysis. Pipeline that includes mapping expression data from 92 normalized cDNAs to genomic loci were used to identify drought tolerant genes. Integrative analysis was carried out using sequence similarity search, metabolic pathway, gene expression profiling and orthology relation to investigate genes of interest. Gene structure prediction was conducted using combination of ab initio and extrinsic evidence-driven information employing multi-criteria sources to improve accuracy. Gene ontology was used to cross-validate and to functionally assign and enrich genes. An integrated approach that subtly combines functional ontology based semantic data with expression profiling and biological networks was employed to analyse gene association with plant phenotypes and to identify and genetically dissect complex drought tolerance in sorghum. The gramene database was used to identify genes with direct or indirect association to drought related ontology terms in sorghum. Where direct association for sorghum genes were not available, genes were captured using Ensemble Biomart by transitive association based on the putative functions of sorghum orthologs in closely related species. Ontology mapping represented a direct or transitive association of genes to multiple drought related ontology terms based on sorghum specific genes or orthologs in related species. Correlation of genes to enriched gene ontology (GO)-terms (p-value < 0.05) related to the whole-plant structure was used to determine the extent of gene-phynotype association across-species and environmental stresses.
114

Evaluation of Management Strategies for the Headworm Complex in Grain Sorghum

Dobbins, Christopher Scott 07 May 2016 (has links)
During 2013 and 2014, studies were conducted to determine the effects of Helicoverpa zea and Spodoptera frugiperda on both damage and yield of Sorghum bicolor. Results from damage ratings suggest that the amount of damage per single larva decreases as population density increases. Also, yield results suggest that one H. zea and one S. frugiperda larva per panicle results in a 3.6 and 4 percent yield loss, respectively. Additionally, a dynamic EIL was determined using crop value along with various yield potentials and control costs. Other research studies were conducted to determine the efficacy of diamide and pyrethroid insecticides on headworms when applied at midge timing for different locations and planting dates. Results suggest that diamides provide longer and better control of headworms than do pyrethroids. However, applying diamides as a preventative application at midge timing may not be economically feasible when grain prices are low.
115

Caratterizzazione di genotipi di sorgo in funzione di tratti legati alla tolleranza alla siccità / CHARACTERIZATION OF SORGHUM GENOTYPES FOR TRAITS RELATED TO DROUGHT TOLERANCE

FRACASSO, ALESSANDRA 28 January 2015 (has links)
L’incessante aumento della popolazione mondiale ed il conseguente incremento della richiesta di risorse alimentari ed energetiche, congiuntamente al mutevole scenario climatico, sempre più incline a periodi di siccità prolungata in misura sempre maggiore in alcune zone del pianeta, fa sì che sempre più attenzione sia rivolta allo sviluppo ed all’implementazione di risorse energetiche rinnovabili a bassi input. Il sorgo zuccherino (Sorghum bicolor Moench) è una coltura bioenergetica in grado di fornire cibo, bioetanolo e biogas. Lo studio di tale coltura in risposta al deficit idrico promuove una più approfondita conoscenza dei meccanismi alla base dei processi fotosintetici, e di come, e quanto, questi possano essere influenzati dall’assenza temporanea, o più o meno prolungata, di disponibilità idrica. La produzione di biomassa e la sua composizione chimica sono state valutate per genotipi di nuova costituzione in confronto a quelli già disponibili in commercio, ai fini della produzione di biogas e bioetanolo. Una più approfondita analisi fisio-fenologica e molecolare è stata condotta su sei genotipi di sorgo con lo scopo di combinare in una visione di insieme più integrata la risposta alla siccità in sorgo. Due genotipi (uno sensibile e l’altro tollerante la siccità) sono stati selezionati per l’analisi trascrittomica in risposta allo stress idrico al fine di individuare geni candidati potenzialmente utili ai fini di una selezione assistita da marcatore. / Due to the increasing human population and the consequent surging energy and water demand, it is necessary to implement energy and fuel production from low input renewable sources. Sweet sorghum (Sorghum bicolor Moench) is a low input multipurpose crop that provides food, feed and bioethanol from conversion of sugars accumulated in the stalk and biogas from anaerobic digestion of whole aboveground dry biomass. This multipurpose crop was studied in response to water deficit. In particular, the biomass production and its composition were evaluated in response to drought for new developed and commercial genotypes for biogas and bioethanol production. The physiologic and molecular approaches were combined in order to provide an integrated view on drought tolerance in sorghum enabling to know which are the mechanisms and with which extent they were affected by drought in this bioenergy crop. The transcriptomic analysis was performed on two sorghum genotypes (one sensitive and the other one tolerant to drought) with RNA-Seq technology in order to evaluate the diversity existing in the sorghum transcriptome that could be related to drought tolerance and to identify candidate genes that could be used as potentially marker for the marker assisted selection.
116

Analýza parametrů, u nichž se předpokládá souvislost se suchovzdorností, u různých genotypů čiroku / Analysis of parameters presumably associated with drought-resistance in various sorghum genotypes

Panchártek, Daniel January 2013 (has links)
The aims of this work were 1) to assess whether sorghum (Sorghum bicolor (L.) Moench) genotypes originating from the India can be grown and analyzed in the climatic conditions of central Europe and 2) to find out the utilization potential of selected non- destructive and destructive methods based mostly on the chlorophyll a fluorescence measurements and the determination of photosynthetic pigments' content for the differentiation of sorghum genotypes based on their presumed drought tolerance. Field experiments made during 2 years compared 15 genotypes of this species (2 stay-green parental lines, 2 senescent parental lines and 11 introgression lines with stay-green loci), 2 of these genotypes were further analyzed in greenhouse conditions where the water deficit was induced by a cessation of watering for 12 days. The field-grown plants showed some differences between individual genotypes in all measured parameters; however, for the majority of the genotypes these differences were not statistically significant. The stay-green parental genotype B35 differred the most from the other ones in both field seasons, but the other stay-green genotypes usually did not differ from the senescent genotypes. No significant differences between both greenhouse-tested genotypes (presumably contrasting in their...
117

Qualidade fisiológica e associação de Fusarium spp. a sementes de sorgo sacarino / Physiological quality and association of Fusarium spp. With seeds of sweet sorghum

Müller, Juceli 07 April 2017 (has links)
The present work aims to determine the physiological and sanitary quality of Sweet sorghum (Sorghum bicolor (L.) Moench) seeds, as well as to identify pathogens associated with seed, their transmission to seedlings and the subsequent pathogenicity of isolates obtained, In addition, molecularly identify the fungal species pathogenic to this crop. The experiments were carried out in the Teaching and Seed Research Laboratory (TSRL), of the Plant Engineering Department; In the Elocy Minussi Phytopathology Laboratory, Department of Plant Protection, and at the Biological Institute of São Paulo. Sweet sorghum seeds were used, all without chemical treatment. Sanitary quality was evaluated by sanity test, and physiological characteristics by germination and vigor tests (seedling length, dry mass, emergence, rate of emergence and accelerated aging). It was performed the test of transmission of the pathogens associated to the seeds and the subsequent pathogenicity of the obtained isolates, culminating with the molecular characterization of the identified pathogens, in which were sequenced the Internal Transcribed Spacer (ITS) genomic regions and the Elongation Factor 1 - alpha (TEF1-α) gene. The design used was the completely randomized design, with four cultivars of Sweet sorghum (BRS 506, F19, BRS 511 and BRS 509); For the evaluation of pathogenicity, the factorial scheme is represented by four cultivars and three isolates of Fusarium spp., besides the witness. The seeds of the BRS 509 cultivar were considered to have lower physiological quality than the other cultivars. The DNA sequencing allowed identifying the Fusarium thapsinum species as a pathogenic agent in the sweet sorghum crop, and proven its transmission via seeds. / O presente trabalho teve como objetivo determinar a qualidade fisiológica e sanitária de sementes de cultivares de sorgo sacarino (Sorghum bicolor (L.) Moench), bem como identificar os patógenos associados à semente, sua transmissão às plântulas e a posterior patogenicidade de isolados obtidos, além disso, identificar molecularmente as espécies fúngicas patogênicas a esta cultura. Os experimentos foram realizados no Laboratório Didático e de Pesquisas em Sementes (LDPS), do Departamento de Fitotecnia; no Laboratório de Fitopatologia Elocy Minussi, do Departamento de Defesa Fitossanitária e, no Instituto Biológico de São Paulo. Foram utilizadas sementes de sorgo sacarino, todas sem tratamento químico. A qualidade sanitária foi avaliada pelo teste de sanidade, e as características fisiológicas por meio dos testes de germinação e de vigor (comprimento de plântulas, massa seca, emergência, índice de velocidade de emergência e envelhecimento acelerado). Foi realizado o teste de transmissão dos patógenos associados à semente e a posterior patogenicidade dos isolados fúngicos obtidos, culminando com a caracterização molecular dos patógenos identificados, na qual foram sequenciadas as regiões genômicas Internal Transcribed Spacer (ITS) e o gene do fator de elongação 1-α (TEF1α). O delineamento utilizado foi o inteiramente casualizado com quatro cultivares de sorgo sacarino (BRS 506, Fepagro 19, BRS 511 e BRS 509); já para a avaliação da patogenicidade, o esquema fatorial foi representado pelas quatro cultivares e três isolados de Fusarium sp., além da testemunha. As sementes da cultivar BRS 509 foram consideradas de qualidade fisiológica inferior as demais cultivares. O sequenciamento de DNA permitiu identificar a espécie Fusarium thapsinum como agente patogênico na cultura do sorgo sacarino, sendo comprovada sua transmissão via sementes.

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