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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.
81

Increasing the Sustainability of Utah Farms by Incorporating Quinoa as a Novel Crop and Protecting Soil Health

Buckland, Kristine R. 01 May 2016 (has links)
Most of the western United States faces increasing water shortages in the coming years, which will prove a major challenge for maintaining sustainable farms. Incorporating an alternative crop that is well adapted to the projected climate could be a successful approach to increasing the sustainability of farms in the region. Quinoa, Chenopodium quinoa Willd., may be an ideal alternative crop to meet the demands of the Intermountain West. Before widespread adoption of this novel crop can occur, best management strategies need to be documented. This paper provides research on cropping systems, irrigation rates, and weed competition with quinoa. Additionally, the impacts of prior cropping history and compost addition on soil health parameters are presented. Quinoa responded to compost addition in an organic cropping system trial where low soil phosphorous was a limiting nutrient. Cover crops, 70% hairy vetch (Vicia villosa Roth.) and 30% winter wheat (Triticum aestivum L.), provided sufficient nitrogen inputs for the following quinoa crop. In response to a line source irrigation trial, varieties showed optimal irrigation rate from 23- 42 cm of water for biomass accumulation, although no seed was produced by any variety. In a greenhouse weed trial, quinoa was less impacted by the presence of any other species, lambsquarters (Chenopodium album L.), red root pigweed (Amaranthus retroflexus) and green foxtail (Setaria viridis), suggesting a high competitive advantage. Finally, organically managed soil increased soil health indicators, including microbial biomass and resistance to stress, regardless of compost addition. In addition, compost increased soil health indicators in conventionally managed soil. Seed set across all field trials was hindered by peak summer temperatures above 32°C, a known temperature sensitivity threshold during flowering for the varieties tested. Therefore, further work to select adapted varieties for the region must be accomplished before widespread adoption is feasible. An integrated approach involving a locallyadapted novel crop and soil health protection promises to increase future farm sustainability.
82

Assessment of Chenopodium quinoa Willd. Genetic Diversity in the USDA and CIP-FAO Collections Using SSR?S and SNP?S

Christensen, Shawn A. 23 November 2005 (has links) (PDF)
Quinoa (Chenopodium quinoa Willd.) is a staple grain for the indigenous people of the Andean region of South America with excellent nutritional qualities, including protein content. The objective of this study is to report on the development of fluorescence-tagged simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs) to (1) genetically characterize the inherent diversity of 152 accessions of C. quinoa; (2) determine to what degree the CIP-FAO collection represents the range of genetic diversity in quinoa; and (3) test four hypotheses regarding quinoa?s center of diversity, Highland and Lowland clustering patterns, origin of Lowland varieties, and the origin of domestication. Thirty-five SSR loci comprising 432 alleles ranging from 5 (QAAT10) to 28 (QAAT50) alleles per locus (mean=13) were used to survey the 152 accessions of quinoa from the USDA and CIP-FAO collections. Heterozygosity was detected in 14.25% of the accessions for SNP loci and in at least one locus for 51% of the accessions. Both UPGMA and PCA analyses partitioned the quinoa accessions into two main clusters. The first major cluster consisted of accessions from the Andean highlands of Peru, Bolivia, Ecuador, Argentina, and extreme northeastern Chile. The other main cluster contained accessions from both the Lowlands of Chile and those collected by Emigdio Ballón The CIP-FAO collection appears to give a good representation of quinoa's genetic diversity within these two main clusters. The significance of patterns of genetic diversity within C. quinoa is discussed.
83

Application of different levels of byproducts from quinua (Chenopodium quinoa Willd.) in the preparation of rations for guinea pigs (Cavia porcellus L.) in the growing and fattening stages

Aduviri Paredes, Grover Antonio 01 January 2006 (has links) (PDF)
From quinua crop residue it is possible to obtain byproducts that can be used to feed small animals, especially guinea pigs. These byproducts can become an alternative feed to ameliorate food deficiencies generally present in the Altiplano. This study compared the effect of consumed quinua meal rations on guinea pig body weight increase and food and economic conversion. This project was developed in two phases: pre-experimental and experimental. In the first phase, genetic material appropriate for the project and the initial rations for consumption was acquired. The second phase included the experimental design where the treatments were developed. The study concluded that a diet of 30% of dry quinua residue completely substituted a diet of wheat meal. This study also presented information on a bactericidal effect of consumed quinua in the digestive tract, resulting in improved weight increase and feed conversion.
84

Evaluation of quinoa (Chenopodium quinoa Willd) at different spacings between furrows and plants in the Mamani community

Ferrufino Miranda, José 01 January 2003 (has links) (PDF)
This study addressed spacing between furrows and plants in the cultivation of the quinoa variety Patacamaya. This study took place from 1999 to 2000 in the Mamani community, Ingavi, La Paz, Bolivia. The Patacamaya variety is a cross between Samaranti (sweet) and Kaslala (bitter), with a vegetative cycle of 145 days (semi-early). It has large grains, is sweet, and has a high grain yield. The spaces between furrows were 40, 60, and 80 cm in an experimental design of randomly divided plots with four repetitions. The spaces between furrows were implemented in large plots and the plant spaces as sub-treatments in small plots. The results showed that the height of the plants were similar in all treatments except for T1 that was 35% lower compared with the other treatments. The highest grain yields occurred in treatment T6 with a value of 2,708.5 kg/ha, followed by T1 and T11. The lowest grain yields occurred in treatments T15, T10, and T5 with values of 1,124.3, 1561.4, and 1653.3 kg/ha, respectively.
85

Characterization of the Granule-Bound Starch Synthase I Gene in Chenopodium

Brown, Douglass C 01 June 2014 (has links)
Chenopodium L. is a relatively under-studied genus that includes the cultivated seed crop quinoa (Chenopodium quinoa Willd.). Quinoa is an allotetraploid (2n=4x=36, AABB genomes) that is cultivated by subsistence farmers and commercial growers in the Andean regions of South America. Approximately 60% of a quinoa seed is starch, a glucose polymer that is an important carbohydrate energy source in the human diet. Seed starch is normally comprised of amylose and amylopectin in a 1:3 ratio, but starches with different amylose:amylopectin ratios have different properties and potential uses. The accumulation of the amylose fraction of starch is controlled by a single dominant gene in quinoa, GBSSI. We report the sequencing and characterization of the GBSSI gene in 18 accessions of Chenopodium, including Andean quinoa and the related Mesoamerican chenopod grain species, C. berlandieri subsp. nuttalliae Saff. Two distinct homoeologs (GBSSIa and GBSSIb) were identified in the tetraploid accessions, and 19 different alleles were identified, including three null mutants – one in an accession of quinoa and two in a waxy landrace of C. berlandieri subsp. nuttalliae, referred to as ‘H02’. Expression analysis of the null mutants revealed that GBSSIa and GBSSIb were both strongly expressed late in quinoa and C. berlandieri subsp. nuttalliae seed development. Starch phenotyping indicated that ‘H02’ produced no amylose, likely due to its having two mutated copies of GBSSI. GBSSI sequences were used to analyze the phylogenetic relationships between quinoa and other members of the Chenopodium genus. This study and the discovery of Chenopodium GBSSI null-mutants will assist in the development of new Chenopodium crops with novel starches.
86

Effect of heat stress on in vitro pollen germination and pollen tube elongation of Chenopodium quinoa and wild relatives

Morris, Angel 11 1900 (has links)
Climate change is one of the biggest challenges facing agriculture today. Transient or prolonged heat stress can be detrimental to plant reproductive development. The male gametophyte, pollen, is particularly sensitive to heat stress, resulting in sterile pollen (pre-anthesis) or deformed/stunted pollen tubes (post-anthesis). Quinoa (Chenopodium quinoa Willd.) has recently seen a rise in global interest due to its nutritional qualities, but global expansion of quinoa is partially hindered by its susceptibility to heat. It has been hypothesized that introgression of heat tolerance traits from wild relatives that occupy warmer environments can increase thermotolerance in quinoa. The goal of this research was to investigate the effect of heat stress on mature pollen grains from quinoa and its wild relatives, C. berlandieri and C. hircinum. To answer this question, several experiments were performed: 1. The nuclear number of the pollen of wild relatives was assessed to determine whether mature pollen grains were released at the trinucleate stage. All pollen was found to be trinucleate. 2. Pollen germination medium was optimized for four accessions: C. quinoa (QQ74; PI 614886), C. berlandieri var. zschackei (CB; BYU14118), and C. hircinum (CHA; Hircinum-069 and CHC; BYU17105). Optimal sucrose and PEG concentrations were determined to be: 5% sucrose/20% PEG for QQ74 and CB; 20% sucrose/0% PEG for CHA; and 10% sucrose/20% PEG for CHC. 3. Temperature optima for pollen germination for QQ74 was 32°C-36°C; CB was 30°C-34°C; CHA was 36°C; and CHC was 32°C -34°C. Overall, pollen from wild relatives was not found to be more heat-tolerant than pollen from domesticated quinoa. 4. Pollen tube elongation over time was observed for all four accessions at 34°C and 38°C, with CHA and QQ74 having the lowest decrease in rate at 38°C (35 and 45%, respectively). This study provides a new method for pollen collection for quinoa and its wild relatives, further optimizes the pollen germination media for QQ74, introduces pollen germination media for three wild accessions, and investigates the effect of heat stress on mature pollen grains. These observations can be employed in future studies investigating heat stress response of pollen in quinoa and its wild relatives.
87

Substituição parcial de farinha de trigo por farinha de amaranto (Amaranthus cruentus L.), quinoa (Chenopodium quinoa W.) e maca (Lepidium meyenii W.) na elaboração de panetone / Partial substitution of wheat flour by amaranth (Amaranthus cruentus L.), quinoa (Chenopodium quinoa W.) and maca (Lepidium meyenii W.) flours in the preparation of panettone

Valcarcel Yamani, Beatriz 02 June 2015 (has links)
O aumento da demanda por alimentos saudáveis está estimulando inovações e o desenvolvimento de novos produtos na indústria de alimentos. O amaranto (Amaranthus cruenthus L.) e a quinoa (Chenopodium quinoa W.) são pseudocereais que apresentam proteínas de elevado valor biológico e ácidos graxos insaturados além de outros compostos que atuam como antioxidantes. A maca (Lepidium meyenii W.), uma raiz anual ou bienal, é usada como ingrediente alimentar devido ao seu valor nutricional e conteúdo de fitoquímicos. Neste trabalho, objetivou-se avaliar o efeito da adição das farinhas destas cullturas em diferentes níveis sobre as propriedades físico-químicas, reológicas e sensoriais de panetone. Farinhas mistas de trigo e amaranto, quinoa ou maca nas porcentagens de 10 %, 20 %, 30 % e 40 % de adição, foram avaliadas durante as diferentes etapas de produção: misturas de farinhas, massa fermentada, massa assada e produto acabado. A adição favoreceu o escurecimento gradual das farinhas e variação no tamanho médio das partículas. Nas massas, foi observada a diminuição gradativa dos valores de estabilidade ao amassamento e tempo de desenvolvimento com diminuição da extensibilidade e aumento da resistência das massas. Nas massas fermentadas, a adição de 10 e 20 % de farinha de amaranto ou quinoa e 30 % de farinha de amaranto, não incrementou significativamente (p > 0,05) a firmeza da massa. No entanto, as formulações contendo farinha de maca mostraram aumento significativo (p < 0,05) no ponto de quebra, firmeza, consistência, coesividade e viscosidade da massa. O aumento da resistência com diminuição gradativa da extensibilidade das massas também foi observado. Nas massas assadas, houve diminuição da área total de células com aumento no número de células de gás de menor tamanho em amostras com adição de farinha de maca e amaranto. As formulações com 10 % de farinha de maca, 10 e 20 % de farinha de amaranto ou quinoa e 30 % de farinha de amaranto, apresentaram os melhores resultados, com valores de volume, altura, cor e firmeza próximos à formulação controle. A análise sensorial mostrou que o produto elaborado com adição de 30 % de farinha de amaranto apresentou a melhor aceitabilidade e intenção de compra. Dentro das condições experimentais, o panetone contendo 30 % de farinha de amaranto foi o mais promissor pela boa aceitabilidade do consumidor, podendo contribuir para incrementar a qualidade do produto. O panetone com 10 % de adição de farinha de maca também apresentou valores interessantes com pouca diferença se comparado com aquele enriquecido com farinha de amaranto. Na amostra contendo farinha de quinoa, a substituição com menos de 20 % de adição melhoraria a aceitabilidade do panetone enriquecido. / The increased demand for healthy foods is stimulating innovation and new product development in the food industry. Amaranth (Amaranthus cruenthus L.) and quinoa (Chenopodium quinoa W.) are pseudocereals which have proteins with high biological value and unsaturated fatty acids, as well as other compounds which act as antioxidants. Maca (Lepidium meyenii W.), an annual or biennial root, is used as a food ingredient for human consumption due to its nutritional value and phytochemical content. The objective of this study was to evaluate the effect of amaranth, quinoa and maca flour addition at different levels on the physical-chemical, rheological and sensory properties of panettone. Composite flours of wheat and amaranth, quinoa or maca flours in percentages of 10 %, 20 %, 30 % and 40 % addition were evaluated during the different stages of production: flour blends, fermented dough, baked dough and finished product. The addition promoted a gradual flour darkening and tendency to yellow and red colors. In the dough, the gradual decrease in stability values to kneading and development time with decreased extensibility and increased dough resistance, were observed. In fermented doughs, the addition of 10 % - 20 % amaranth or quinoa flour and 30 % amaranth flour, did not increased significantly (p > 0.05) the dough firmness. However, formulations containing maca flour showed a significant increase (p < 0.05) of break point, firmness, consistency, cohesiveness and viscosity of the dough. Furthermore, it was also observed an increase in dough resistance with a gradual decrease in extensibility. In baked samples, there was a decrease of the total cell area with increased number of smaller gas cells in samples with maca and amaranth flour addition. Better results were observed in formulations with 10% maca flour, 10 - 20 % amaranth or quinoa flour and 30 % amaranth flour with values of volume, height, color and firmness close to the control. Sensorial analysis showed that sample containing 30 % addition of amaranth flour showed the better acceptability and purchase intention by consumers. Within these experimental conditions, panettone containing 30 % amaranth flour was the most promising for the good acceptability of the consumer and may contribute to improve the quality of the product. Sample with 10 % maca flour addition also showed interesting values with few differences when compared to that enriched with amaranth flour. In sample containing quinoa flour, wheat flour substitution with less than 20 % would improve the acceptability of the enriched panettone.
88

Substituição parcial de farinha de trigo por farinha de amaranto (Amaranthus cruentus L.), quinoa (Chenopodium quinoa W.) e maca (Lepidium meyenii W.) na elaboração de panetone / Partial substitution of wheat flour by amaranth (Amaranthus cruentus L.), quinoa (Chenopodium quinoa W.) and maca (Lepidium meyenii W.) flours in the preparation of panettone

Beatriz Valcarcel Yamani 02 June 2015 (has links)
O aumento da demanda por alimentos saudáveis está estimulando inovações e o desenvolvimento de novos produtos na indústria de alimentos. O amaranto (Amaranthus cruenthus L.) e a quinoa (Chenopodium quinoa W.) são pseudocereais que apresentam proteínas de elevado valor biológico e ácidos graxos insaturados além de outros compostos que atuam como antioxidantes. A maca (Lepidium meyenii W.), uma raiz anual ou bienal, é usada como ingrediente alimentar devido ao seu valor nutricional e conteúdo de fitoquímicos. Neste trabalho, objetivou-se avaliar o efeito da adição das farinhas destas cullturas em diferentes níveis sobre as propriedades físico-químicas, reológicas e sensoriais de panetone. Farinhas mistas de trigo e amaranto, quinoa ou maca nas porcentagens de 10 %, 20 %, 30 % e 40 % de adição, foram avaliadas durante as diferentes etapas de produção: misturas de farinhas, massa fermentada, massa assada e produto acabado. A adição favoreceu o escurecimento gradual das farinhas e variação no tamanho médio das partículas. Nas massas, foi observada a diminuição gradativa dos valores de estabilidade ao amassamento e tempo de desenvolvimento com diminuição da extensibilidade e aumento da resistência das massas. Nas massas fermentadas, a adição de 10 e 20 % de farinha de amaranto ou quinoa e 30 % de farinha de amaranto, não incrementou significativamente (p > 0,05) a firmeza da massa. No entanto, as formulações contendo farinha de maca mostraram aumento significativo (p < 0,05) no ponto de quebra, firmeza, consistência, coesividade e viscosidade da massa. O aumento da resistência com diminuição gradativa da extensibilidade das massas também foi observado. Nas massas assadas, houve diminuição da área total de células com aumento no número de células de gás de menor tamanho em amostras com adição de farinha de maca e amaranto. As formulações com 10 % de farinha de maca, 10 e 20 % de farinha de amaranto ou quinoa e 30 % de farinha de amaranto, apresentaram os melhores resultados, com valores de volume, altura, cor e firmeza próximos à formulação controle. A análise sensorial mostrou que o produto elaborado com adição de 30 % de farinha de amaranto apresentou a melhor aceitabilidade e intenção de compra. Dentro das condições experimentais, o panetone contendo 30 % de farinha de amaranto foi o mais promissor pela boa aceitabilidade do consumidor, podendo contribuir para incrementar a qualidade do produto. O panetone com 10 % de adição de farinha de maca também apresentou valores interessantes com pouca diferença se comparado com aquele enriquecido com farinha de amaranto. Na amostra contendo farinha de quinoa, a substituição com menos de 20 % de adição melhoraria a aceitabilidade do panetone enriquecido. / The increased demand for healthy foods is stimulating innovation and new product development in the food industry. Amaranth (Amaranthus cruenthus L.) and quinoa (Chenopodium quinoa W.) are pseudocereals which have proteins with high biological value and unsaturated fatty acids, as well as other compounds which act as antioxidants. Maca (Lepidium meyenii W.), an annual or biennial root, is used as a food ingredient for human consumption due to its nutritional value and phytochemical content. The objective of this study was to evaluate the effect of amaranth, quinoa and maca flour addition at different levels on the physical-chemical, rheological and sensory properties of panettone. Composite flours of wheat and amaranth, quinoa or maca flours in percentages of 10 %, 20 %, 30 % and 40 % addition were evaluated during the different stages of production: flour blends, fermented dough, baked dough and finished product. The addition promoted a gradual flour darkening and tendency to yellow and red colors. In the dough, the gradual decrease in stability values to kneading and development time with decreased extensibility and increased dough resistance, were observed. In fermented doughs, the addition of 10 % - 20 % amaranth or quinoa flour and 30 % amaranth flour, did not increased significantly (p > 0.05) the dough firmness. However, formulations containing maca flour showed a significant increase (p < 0.05) of break point, firmness, consistency, cohesiveness and viscosity of the dough. Furthermore, it was also observed an increase in dough resistance with a gradual decrease in extensibility. In baked samples, there was a decrease of the total cell area with increased number of smaller gas cells in samples with maca and amaranth flour addition. Better results were observed in formulations with 10% maca flour, 10 - 20 % amaranth or quinoa flour and 30 % amaranth flour with values of volume, height, color and firmness close to the control. Sensorial analysis showed that sample containing 30 % addition of amaranth flour showed the better acceptability and purchase intention by consumers. Within these experimental conditions, panettone containing 30 % amaranth flour was the most promising for the good acceptability of the consumer and may contribute to improve the quality of the product. Sample with 10 % maca flour addition also showed interesting values with few differences when compared to that enriched with amaranth flour. In sample containing quinoa flour, wheat flour substitution with less than 20 % would improve the acceptability of the enriched panettone.
89

Desenvolvimento de pão de forma com adição de quinoa

Gewehr, Márcia Flach January 2010 (has links)
A quinoa é um grão andino com elevado potencial de ser considerada como cultura mundial devido a quantidade e variedade de nutrientes existentes. Este pseudocereal enquadra-se no contexto do mercado consumidor que almeja produtos diferenciados, especialmente com aspectos nutricionais relevantes. Este trabalho teve por objetivo analisar a composição dos flocos de quinoa utilizados, uma vez que fatores genéticos, climáticos, entre outros, interferem na composição dos nutrientes, além de elaborar e avaliar pães de forma adicionados desse pseudocereal. Determinou-se umidade, cinzas, lipídios, composição de ácidos graxos, proteínas, composição em aminoácidos, fibras e suas frações, tocoferóis e minerais (sódio, cálcio, ferro, zinco e fósforo). Em virtude dos flocos apresentarem alto teor protéico, perfil aminoacídico condizente com a recomendação da FAO, elevado teor de fibras, fósforo, ferro, além de maior quantidade de lipídios como ácidos graxos insaturados e quantidades apreciáveis de α, β, γ, e δ-tocoferóis, elaborou-se pães de forma com substituição da farinha de trigo por zero, 10, 15 e 20% de flocos de quinoa, utilizando-se o método esponja de panificação e mantendo-se os parâmetros de processo constantes. Análises físico-químicas foram realizadas na farinha de trigo e nos flocos de quinoa. Determinou-se o volume específico, a cor do miolo e a composição nutricional dos pães. Observou-se que, a adição progressiva de flocos de quinoa, tornou o miolo mais escuro, reduziu o volume específico do pão, elevou de forma crescente o teor de proteína, de fibras totais e insolúveis e de tocoferóis. Pela análise sensorial verificou-se boa aceitabilidade para os pães com substituição da farinha de trigo por 15% e 20% de quinoa e estes foram utilizados para avaliar, através de experimento biológico, os possíveis benefícios à saúde. O aumento de tocoferóis (α, γ, e δ-tocoferóis) no pão com 20% de quinoa melhorou o perfil lipídico do sangue e da gordura do fígado dos animais experimentais, em relação ao pão padrão. Estes resultados indicaram que, possivelmente, os flocos de quinoa poderão ser adicionados em alimentos para agregar valor ao produto. No entanto, novos estudos, envolvendo tipo de processamento e as perdas nutricionais decorrentes destes, devem ser feitos para melhor avaliação. / Quinoa is a grain from the Andes with a high potential as a world wide crop due to the quantity and variety of existing nutrients. This pseudocereal fits into the consumer market context that looks for differentiated products, especially having relevant nutritional aspects. The purpose of this work was to analyze the composition of quinoa flakes used, once genetic and climate factors, among others, interfere in the composition of the nutrients; as well as to develop and evaluate bread loaves with the addition of this pseudocereal. The humidity, ashes, lipid, composition of fat acids, proteins, amino acid composition, fibers and their fractions, tocopherols and minerals (sodium, calcium, iron, zinc and phosphorous) were determined. Due to the fact that the flakes present high protein level, amino acid profile that meets guidelines from FAO, high levels of fibers, phosphorous, iron, besides a higher quantity of lipids as unsaturated fat acids and valuable quantities of α, β, γ, and δ-tocopherols, white bread loaves were developed, substituting quinoa flakes for zero, 10, 15 and 20% of the flour, using the sponge method and maintaining the process parameters constant. Physicochemical analyses were performed both with the flour and quinoa flakes. The specific volume, color of the inner part and nutritional composition of the bread loaves were determined. It was noticed that the progressive addition of quinoa flakes made the inner part become darker, reduced the specific volume of the loaf, and gradually increased the protein level and the level of total and insoluble fibers and the tocopherols. Through sensorial analysis it was observed a good acceptance for the loaves of bread with the replacement of 15% and 20% of flour by quinoa and these were used to evaluate, through a biological experiment, the possible benefits for the health. The increase of tocopherols (α, γ, and δ- tocopherols) in the 20% bread loaf improved the lipid profile of the blood and of fat in the liver of the trial animals, when compared with standard bread. These results indicated that, very likely, the quinoa flakes can be added to food in order to add value to the product. However, further studies, involving the processing and the nutritional loss due to it, must be carried out to perform a better evaluation.
90

Respostas fisiológicas e bioquímicas de plantas de quinoa cv. BRS PIABIRU cultivadas sob condições de salinidade / Physiological and biochemical responses of quinoa cv. BRS Piabiru cultivated under saline conditions

Ávila, Gabriele Espinel 18 September 2015 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-06-22T16:33:35Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_gabriele_espinel_avila.pdf: 937823 bytes, checksum: 425729d85c0200d3520fa3c39b5b7aae (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-06-22T20:38:09Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_gabriele_espinel_avila.pdf: 937823 bytes, checksum: 425729d85c0200d3520fa3c39b5b7aae (MD5) / Made available in DSpace on 2017-06-22T20:38:09Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_gabriele_espinel_avila.pdf: 937823 bytes, checksum: 425729d85c0200d3520fa3c39b5b7aae (MD5) Previous issue date: 2015-09-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Classificada como halófita facultativa, a quinoa (Chenopodium quinoa Willd.) é reconhecida por tolerar elevados níveis de salinidade. No Brasil, a cv. BRS Piabiru é a primeira recomendada para o cultivo granífero, constituindo alternativa para diversificação dos sistemas agrícolas. Contudo, estudos relativos à adaptação dessa cultivar no estado do Rio Grande do Sul, bem como às condições de salinidade ainda são necessários. Portanto, o objetivo deste trabalho foi avaliar as respostas fisiológicas (pigmentos e trocas gasosas) e bioquímicas (atividade enzimática antioxidante, teores de peróxido de hidrogênio, peroxidação lipídica, prolina e potencial osmótico) de plantas de quinoa cv. BRS Piabiru cultivadas sob condições de salinidade. O experimento foi conduzido em casa de vegetação onde as sementes foram distribuídas em vasos plásticos, preenchidos com areia lavada. Após sete dias da germinação foi fornecida solução nutritiva, ministrada a cada quatro dias e, aos 30 dias, foi realizado o desbaste, mantendo-se quatro plantas por vaso. Neste período também foram aplicadas as soluções salinas, na forma de cloreto de sódio, nas concentrações de 100, 200, 300 e 400 mM, além do tratamento controle cuja as plantas foram cultivadas na ausência da salinidade. As soluções nutritiva e salina foram aplicadas intercaladamente, a cada dois dias, até o fim do experimento. Aos 30, 60 e 90 dias após indução dos tratamentos, as plantas foram avaliadas quanto a parâmetros fisiológicos e bioquímicos (análises não destrutivas e destrutivas, respectivamente). Os dados foram submetidos à análise de variância (p≤0,05), as médias comparadas pelo teste de Tukey ao nível de 5% de probabilidade de erro e analisados por regressão polinomial. Houve redução no índice de clorofila e índice de balanço de nitrogênio e, a partir de 60 dias, incremento no índice de flavonoides. Neste período, a taxa de assimilação líquida de CO2 seguiu tendência quadrática de elevação até a concentração de 250 mM e as variáveis eficiência de uso da água e eficiência de carboxilação aumentaram linearmente com o incremento da salinidade. A atividade enzimática antioxidante, através das enzimas superóxido dismutase, catalase e ascorbato peroxidase, demonstrou que a salinidade promoveu adaptação e tentativa de neutralização das espécies reativas de oxigênio produzidas durante o estresse salino, tanto na parte aérea quanto em raízes. Houve aumento no potencial osmótico em ambos órgãos aos 90 dias após indução dos tratamentos, contudo, nas raízes a síntese de prolina não seguiu a mesma tendência. Apesar da redução nos índices de clorofila e de balanço de nitrogênio, há manutenção da taxa fotossintética, a qual, associada a capacidade antioxidante e ao ajuste osmótico até a concentração de 250 mM de NaCl, caracteriza a cv. BRS Piabiru com potencial de cultivo em solos sujeitos a salinização. / Classified as optional halophyte, quinoa (Chenopodium quinoa Willd.) is recognized for tolerate high levels of salinity. In Brazil, the cv. BRS Piabiru is the first recommended for grain production, providing an alternative for diversification of agricultural systems. However, studies on the adaptation of this variety in the state of Rio Grande do Sul, as well as the salinity conditions are still needed. Therefore, the objective of this study was to evaluate the physiological responses (pigments and gas exchange) and biochemical (antioxidant enzyme activity, hydrogen peroxide levels, lipid peroxidation, proline and osmotic potential) of quinoa plants cv. BRS Piabiru cultivated under saline conditions. The experiment was conducted in a greenhouse where the seeds were distributed in plastic pots filled with washed sand. After seven days of germination was supplied nutrient solution administered every four days and at day 30, the trimming was carried out, keeping four plants per pot. During this period the salt solutions have also been applied in the form of sodium chloride at concentrations of 100, 200, 300 and 400 mM, beyond which the control treatment plants were grown in the absence of salinity. The nutrient and saline solutions were applied interchangeably, every two days until the end of the experiment. At 30, 60 and 90 days after induction of treatments, the plants were evaluated for physiological and biochemical parameters (non-destructive and destructive analysis, respectively). Data were subjected to analysis of variance (p≤ 0.05), the averages compared by Tukey test at 5% error probability and analyzed by polynomial regression. There was reduction in chlorophyll content and nitrogen balance index and from 60 days, an increase in flavonoid content. During this period, net assimilation rate of CO2 followed quadratic upward trend until the concentration of 250 mM and the conditions of water use efficiency and carboxylation efficiency increased linearly with increasing salinity. The antioxidant enzyme activity by the enzyme superoxide dismutase, catalase and ascorbate peroxidase showed that the salinity promoted adaptation and attempt to neutralize the reactive oxygen species produced during salt stress, both in shoots and in roots. There was an increase of osmotic potential in both organs 90 days after induction of treatment, however, the roots proline synthesis did not follow the same trend. Despite the reduction in levels of chlorophyll and nitrogen balance, there is maintenance of photosynthetic rate, that, associated with antioxidant capacity and osmotic adjustment, until the concentration of 250 mM of NaCl, featuring the cv. BRS Piabiru with growing potential subjects soil salinization.

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