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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 ingredientes alternativos na alimentação de frangos de corte com a adição de enzimas / Evaluation of alternative ingredients in diets of broilers with the addition of enzymes

Bozutti, Samuel Real de Azevedo 02 March 2009 (has links)
Realizaram-se dois experimentos com o objetivo de avaliar a inclusão dos ingredientes alternativos farelo de girassol e sorgo na alimentação de frangos de corte adicionando-se enzimas. Os experimentos foram divididos em três ensaios independentes, os quais corresponderam a cada fase de criação: fase inicial (1 a 21 dias), onde foram avaliadas as características de desempenho; fase de crescimento (22 a 42 dias), onde foram avaliadas as características de desempenho e as características da carcaça e fase final (43 a 49 dias), onde foram avaliadas as características de desempenho e as características da carcaça. Para cada ensaio foram utilizadas 1.280 aves de ambos os sexos avaliando-se: desempenho (consumo, ganho de peso, conversão alimentar, rendimento de carcaça e rendimento dos cortes comerciais (peito, coxa + sobrecoxa, asa e dorso)), umidade da cama, viscosidade da digesta. Os dados foram submetidos à análise de variância utilizandose o procedimento do programa SAS (Statistic Analisys System, 2001) e como teste de comparação de médias foi utilizado o Teste de Tukey. No primeiro experimento, com farelo de girassol, o delineamento foi o inteiramente casualizado, com 8 tratamentos, em esquema fatorial 2 X 2 X 2 (2 critérios de formulação aminoácidos digestíveis e totais; 2 níveis de inclusão do farelo de girassol 0% e 15%; 2 formas de utilização das enzimas: com adição e sem adição), com 4 repetições de 40 aves cada. Concluiu-se que a utilização de 15% do farelo de girassol na dieta de frangos de corte prejudicou o desempenho dos animais, não afetando o rendimento de carcaça. Nas fases de crescimento e final, o melhor desempenho foi encontrado quando as dietas foram formuladas com base em aminoácidos digestíveis e com adição de enzimas; não influenciando a umidade do material da cama, aumentando a viscosidade da digesta. No segundo experimento com sorgo utilizou-se o mesmo delineamento com 8 tratamentos, em esquema fatorial 2 X 2 X 2 (2 critérios de formulação aminoácidos digestíveis e totais; 2 níveis de substituição do milho pelo sorgo 0% e 100%; 2 formas de utilização das enzimas: com adição e sem adição), com 4 repetições de 40 aves cada. O sorgo demonstrou ser um grande substituto do milho nas dietas, pelo fato de não alterar o desempenho das aves, umidade da cama e viscosidade da digesta. Com os dois ensaios realizados concluiu-se que ingredientes alternativos são viáveis na alimentação das aves, não restringindo a criação das mesmas somente no milho e na soja. / Two experiments were conduced to evaluate the inclusion of alternative ingredients, sunflower meal and sorghum, in diet of broilers with the addition of enzymes. The experiments were divided into three independent trials, which corresponded to each phase of raising: initial phase (1 21 days), where the performance characteristics were evaluated; growing phase (22 42 days), where the performance and the carcass characteristics were evaluated, and the final phase (43 49 days), where the performance and the carcass characteristics were also evaluated. For each trial 1,280 birds of both sexes were used to evaluate: performance (feed intake, wheight gain, feed conversion, carcass yield, and comercial cuts yield (breast, thigh, thigh + thigh of any fowl, wings and back)), litter humidity, digest viscosity. The data were submitted to variance analisys using the procedure of the program SAS (Statistc Analisys System, 2001) and the Tukey Test. In the first experiment, with sunflower meal, with 8 treatments,in factorial study, 2 x 2 x 2 ( 2 formulation digestible and total aminoacids; 2 levels of sunflower meal inclusion 0% and 15%; and enzyme use: with and without addition), with 4 repetitions of 40 poultries each. It was concluded that the use of 15% of the sunflower meal in the broiler´s diet harmed the animals´ performance, not affecting the carcass yield. In the growing and final phases, the best performance was found when the diets were made based on digestible aminoacids and with addition of enzymes; not influencing the humidity of the litter, increasing the digest viscosity. In the second experiment with sorghum 8 treatments were also used, in factorial study 2 x 2 x 2 (2 formulation digestible and total aminoacids; 2 levels of substitution from the corn to the sorghum 0 % and 100%; and enzyme use: with and without addition), with 4 repetitions of 40 poultries each. The sorghum has shown to be a great replacement of the corn in the diets, because it does not alter the poultry performance, bed humidity and digest viscosity. With both experiments performed, it was concluded that the alternative ingredients are feasible in the poultry feeding, not restricting their raising solely on corn and soybeans.
112

Disponibilidade de níquel no sistema solo-planta: efeito de doses e saturações por bases / Nickel availability on soil-plant system: effects of Ni rates and saturations base

Macedo, Fernando Giovannetti de 24 March 2016 (has links)
Por se tratar de um elemento essencial às plantas e um metal pesado ao mesmo tempo, o níquel requer atenção quanto aos aspectos da fisiologia de plantas e ambiental. Além disso, existe um intervalo estreito entre as exigências nutricionais e os teores tóxicos às plantas. Neste contexto, objetivou-se avaliar o efeito do Ni no sistema solo-planta, com foco no ciclo do N e a disponibilidade do elemento no solo, por meio de experimento em condições controladas, utilizando vasos distribuídos inteiramente ao acaso, utilizando-se esquema fatorial 2 x 5, com sete repetições cada tratamento. O primeiro fator foi constituído de duas saturações por base (50 e 70%) e o segundo de cinco doses de Ni (0; 0,1; 0,5; 1,0 e 10,0 mg dm-3 de solo). Os vasos foram preenchidos com 8 dm3 de terra e cultivados com soja [Glycine max (L.) Merrill] sucedida por girassol (Helianthus annuus L.). Os parâmetros qualitativos e quantitativos: altura de plantas (AP), diâmetro do caule (DC), número de nós (NN), estádio fenológico (EF), índice SPAD e, diâmetro do capítulo (DCap) (para girassol) foram avaliadas aos 30 e 60 dias após a emergência (d.a.e.) de cada cultivo. Plantas inteiras de soja, amostradas em quatro vasos de cada tratamento, foram coletadas no estádio R1. Na mesma ocasião foram coletadas amostras de solo da rizosfera. Em seguida, as plantas coletadas foram divididas em: folhas; raízes (nódulos na soja) e parte aérea. Foram determinados nas folhas utilizadas para diagnose em soja e girassol: os teores de macro e micronutrientes, as atividades da redutase do nitrato e da urease e as concentrações dos ácidos orgânicos: oxálico, malônico, succínico, málico, tartárico, fumárico, oxaloacético, cítrico e lático. Os mesmos ácidos orgânicos foram determinados em raízes secundárias de girassol e nódulos de soja. Foram realizadas avaliações ultraestruturais por meio de microscopia eletrônica de transmissão (MET) em raízes de girassol, e estruturais e de tonalidade em nódulos de soja, por meio de microscopia de luz. No solo, foram determinadas: atividade urease, desidrogenase, Ni total e fitodisponível pelos métodos: Mehlich-1, Mehlich-3 e DTPA. No período de maturidade fisiológica de cada cultura foi realizada a colheita das plantas dos vasos restantes para determinação de produção de grãos, teores de Ni na planta inteira e Ni e N nos grãos. Ao final dos dois experimentos foi realizada nova coleta de solo para extração sequencial de Ni. O índice SPAD em soja aos 60 d.a.e., a produção de massa seca da parte aérea da soja e da raiz de girassol foram influenciados pela saturação por bases, doses de níquel e pela a interação destes. Foram influenciados pelas saturações por base e doses de níquel (fatores isolados): para soja: AP aos 60 d.a.e., NN aos 30 e 60 d.a.e., SPAD aos 30 d.a.e.; para girassol: AP e NN aos 30 e 60 d.a.e., DC e SPAD aos 30 d.a.e. As demais variáveis avaliadas aos 30 e 60 d.a.e. foram influenciadas apenas pela saturação por bases, ou doses de Ni separadamente. As plantas de soja e girassol apresentaram maiores teores de Ni nos diferentes tecidos avaliados (exceto grãos) quando cultivadas sob V50%. A produção de grãos de soja e girassol não foi influenciada pelos tratamentos, porém o teor de N dos grãos de soja influenciado pelas doses de Ni na V70%. A atividade da enzima urease nas folhas de soja e girassol foi responsiva positivamente ao aumento das doses de Ni. Quatro dos ácidos orgânicos avaliados e o teor de N nas folhas e nos grãos foram maiores nas plantas cultivadas sob V70% com a dose de 0,5 mg dm-3 de Ni. As doses de Ni bem com as saturações por bases influenciaram diretamente o balanço de nutrientes das plantas. Os extratores Mehlich-1, Mehlich-3 e DTPA apresentaram elevado coefienciente de correlação entre a fração de Ni disponível no solo e a concentração do elemento nas plantas de soja e girassol, sendo o extrator DTPA o que apresentou maior coeficiente de correlação. O Ni apresentou distribuição variável entre as diferentes frações do solo em função dos tratamentos. Os solos dos tratamentos com saturação por bases de 70% apresentaram maior concentração de Ni ligado a carbonato, comparado aos tratamentos sob saturação por bases de 50%. A distribuição do Ni entre as frações do solo seguiu a seguinte orgem: ligado a carbonato < trocável < ligado a óxidos < matéria orgânica < residual. A saturação por bases exerceu efeito diferenciado para a atividade da urease no solo em função da cultura avaliada. Por sua vez, o Ni exerceu efeito diferenciado sobre a atividade de desidrogenase em função da cultura estudada / As an essential element for plants and a heavy metal at the same time, nickel requires attention on the aspects of the physiology of plants and environmental. Furthermore, there is a narrow range between nutritional requirements and toxic levels to plants. In this context, the aim was to evaluate the effect of Ni in soil-plant system through experiment under controlled conditions, using soil pots distributed entirely at random, using a factorial 2 x 5, with seven repetitions each treatment. The first factor was formed of two saturations base (50 and 70%) and the second of five Ni rates (0, 0.1, 0.5, 1.0 and 10.0 mg dm-3 of soil). The pots were filled with 8 dm3 of soil and sown with soybean [Glycine max (L.) Merrill] succeeded by sunflower (Helianthus annuus L.). The agronomic traits: plant height (PH), stem diameter (SD), number of nodes (NN), phenological stage (PS), SPAD index, head diameter (HD) (Sunflower) were evaluated at 30 and 60 days after emergence (dae) of each crop. Whole soybean plants, sampled in four pots of each treatment were collected at the R1 stage for analysis of soil samples from the rhizosphere. Then, the collected plants were divided into: sheets; roots (nodules on soybean) and shoot. Were determined in the leaves used for diagnosis in soybean and sunflower: macro and micronutrients, activities of nitrate reductase, and urease and concentrations of organic acids: oxalic, malonic, succinic, malic, tartaric, fumaric, oxaloacetic, citric and lactic. The same organic acids were determined in secondary roots of sunflower and nodules of soybean. They were conducted ultrastructural evaluations by means of transmission electron microscopy (TEM) in sunflower roots, and color in soybean nodules, using light microscopy. In the soil were determined: urease activity dehydrogenase, the total Ni and available by methods: Mehlich-1, Mehlich-3 and DTPA. At physiological maturity period of each culture was performed to harvest the plants of other pots in order to determine grain dry matter yield, Ni content in the whole plant and Ni and N content in grains. At the end of the two experiments it were carried out new soil sampling for Ni sequential extraction. The SPAD index taken on soybean leaves at 60 d.a.e., the dry matter production of the aerial part of soybean and sunflower root were influenced by the base saturation, nickel doses and the interaction among them. They were influenced by the saturation for base and nickel doses (single factor): soybean: HP d.a.e. to 60, NN at 30 and 60 d.a.e., SPAD to 30 d.a.e.; Sunflower: PH and NN at 30 and 60 d.a.e., HD and SPAD to 30 d.a.e. The other variables assessed at 30 and 60 d.a.e. They were influenced only by base saturation, or Ni doses separately. Sunflower soybean plants had higher Ni contents at the different tissues (except grain) when grown under V50%. The production of soybean and sunflower grains was not affected by the treatments, but the N content of the soybeans was changed by Ni rates V70%. The urease enzyme activity in soybean and sunflower leaves was responsive to increased doses of Ni. Four of the organic acids and the N content in leaves and grains were higher in plants grown under V70% at the dose of 0.5 mg dm-3 Ni. Ni rates as well as the cation base saturation directly influenced the balance of plant nutrients. The Mehlich-1, Mehlich-3 and DTPA presented higher coefiencient correlation between available Ni soil fraction with nutrient concentrations in both soybean and sunflower, with the DTPA solution showing the highest correlation coefficient in this analysis. Ni showed variable distribution among different soil fractions in the treatments. The treatments presented soil under cation bases saturation of 70% showed higher Ni concentration linked to carbonate, as compared to treatments under cation base saturation of 50%. The distribution of Ni between the soil fractions followed the following order: bound to carbonate <exchangeable < bound to oxides <organic matter <residual. The cation base saturation showed different effects on the urease activity according to the plant evaluated. Ni exerted on the differential effect dehydrogenase activity according to the plant specie
113

Contribution des pollinisateurs dans la production de colza et de tournesol en zone atelier « Plaine et Val de Sèvre » / Contribution of pollinators to oilseed rape and sunflower production in the zone atelier « Plaine and Val de Sèvre ».

Perrot, Thomas 15 June 2018 (has links)
La pollinisation entomophile est essentielle pour la production de 70% des cultures à travers le monde. Cependant la contribution des pollinisateurs dans la production agricole reste peu renseignée ainsi que les insectes qui sont impliqués. De plus, lorsque la contribution des pollinisateurs est quantifiée, le bénéfice est calculé à des échelles biologiques ou dans des conditions simplifiées qui peuvent être non représentatifs des bénéfices à l’échelle de la parcelle. Par ailleurs, les possibles interactions entre les pollinisateurs et les pratiques agricoles ne sont généralement pas pris en compte. L’objectif général de cette thèse était donc de quantifier la contribution des pollinisateurs directement dans les parcelles agricoles dans deux cultures fréquemment retrouvées en Europe, le colza et le tournesol. Ces estimations sont réalisées à l’échelle de la parcelle ainsi qu’à l’échelle de la plante pour comprendre les mécanismes qui permettent l’augmentation de la production agricole. Ces études nous ont permis aussi d’identifier les principaux pollinisateurs de ces deux cultures.Dans un premier temps, nous avons quantifié le bénéfice des pollinisateurs dans les rendements de tournesol et de colza. Nous montrons que le colza et le tournesol partagent une même guilde de pollinisateurs, les abeilles domestiques. Les abeilles sauvages sont aussi d’importants pollinisateurs pour le colza. Les pollinisateurs augmentent les rendements de colza de plus de 35% et ceux du tournesol de 40%, à l’échelle de la parcelle. A l’échelle de la plante, que ce soit pour le colza et le tournesol, les pollinisateurs augmentent le succès de pollinisation et donc le nombre de graines par plante.Dans un deuxième temps, nous avons comparé le bénéfice des pollinisateurs par rapport à ceux des pratiques agricoles en termes de rendement et de gain monétaires dans les parcelles de colza, tout en regardant plus précisément leurs possibles interactions. Nous montrons que le bénéfice des pollinisateurs dans les rendements s’additionnent à ceux des pratiques agricoles excepté avec les insecticides qui réduisant la contribution des pollinisateurs. De plus, nous montrons que les pollinisateurs sont d’importants contributeurs du rendement et des revenus agricoles en augmentant le bénéfice des agriculteurs de 250 € par hectare alors qu’au contraire plusieurs pratiques peuvent être très couteuses pour ces mêmes agriculteurs. Finalement, nous étudions l’effet des pollinisateurs sur la qualité lipidique des graines de colza qui est une autre facette de la production agricole. Nous montrons que les abeilles domestiques améliorent la qualité des graines en augmentant le pourcentage d’acides gras insaturés tout en réduisant les acides gras trans- et saturés. Pour certaines années, les abeilles domestiques augmentent aussi le pourcentage de lipide par graine.En conclusion, nous montrons que les pollinisateurs sont essentiels à la production agricole à la fois sur le rendement, les revenus agricoles et sur la qualité. Plusieurs mesures doivent être mises en place pour promouvoir les pollinisateurs dans les milieux agricoles dans le but de les préserver et d’assurer une production agricole durable pour ces deux cultures. / Insect pollination is essential for over 70% of crops around the world. However, the contribution of pollinators to crop production and the insects involved in crop pollination have rarely been studied. Moreover, assessments of pollinator contributions have mostly been conducted on a small scale or under simplified conditions, which do not represent the real contributions at the field scale and do not take into account possible interactions between pollinators and farming practices. The aim of this study is to quantify directly under field conditions, the contribution of pollinators in two crops frequently cultivated in Europe: oilseed rape and sunflower. Estimations are realized both at the plant and at the field scale to understand mechanisms that increase crop production. Our studies identify also these crops’ pollinators.In a first step, we quantified the contributions of pollinators to oilseed rape and sunflower yield. Oilseed rape and sunflower share a pollinator guild - the honeybee. Wild bees also increase oilseed rape yield. Pollinators increase the yield of oilseed rape by up to 35% and of sunflower by up to 40%. At the plant scale, pollinators increase pollination success and consequently the number of seeds per plant.In a second step, we compared for oilseed rape the yield and the monetary contributions of pollinators and farming practices by taking their potential interactions more accurately into account. We show that the benefits of pollinators and farming practices on yield were additive except for insecticide use, which decreased the contribution of pollinators. In addition, we show that pollinators were important contributors to the farmers’ incomes by increasing gain by 250 € per hectare while some practices were very expensive for farmers.Finally, the effect of pollinators was studied on oilseed rape seed quality - another component of crop production. We show that honeybees improve seed quality by increasing the percentage of unsaturated fatty acids in seeds and decreasing trans-saturated and saturated fatty acids. In some years, honeybees increased also the percentage of lipids per seed.We conclude, pollinators are essential for crop production by increasing both yield, monetary gain and quality. Several measures must be taken to promote pollinators in agricultural land in order to conserve them and ensure sustainable crop production for these two crops.
114

Síntese e caracterização de biodiesel obtido via catálises homogênea e heterogênea de óleo extraído de sementes de Helianthus annuus / Synthesis and characterization of biodiesel produced via homogeneous and heterogeneous catalysis of oil extracted from the feel of Helianthus annuus

Viviane Fernandes da Silva 29 March 2011 (has links)
O biodiesel é definido como um mono alquil éster de ácidos graxos de cadeia longa derivado de fontes renováveis tais como óleos vegetais e gorduras animais. Sua importância esta associada ao uso como um combustível alternativo para motores do ciclo Diesel podendo ser utilizado puro ou em misturas com o diesel representando economia de petróleo e menor poluição ambiental. Em geral é obtido por meio da reação de transesterificação na qual os triacilgliceróis, principais constituintes dos óleos e gorduras reagem com álcool, em presença de um catalisador ácido ou básico, produzindo ésteres de ácidos graxos e glicerol. A transesterificação pode ser conduzida por catálise homogênea ou heterogênea. O grande desafio da indústria é otimizar o processo a fim de alcançar um produto e uma rota de produção tecnologicamente eficiente e ambientalmente correta. O objetivo desta pesquisa foi estudar a síntese do biodiesel utilizando o processo de transesterificação do óleo de girassol por catálises homogênea e heterogênea. Foram realizadas reações de transesterificação via rotas metílica e etílica, empregando como catalisador homogêneo alcóxido de potássio e como catalisador heterogêneo a resina comercial de troca iônica Amberlyst 26 / Biodiesel is defined as a long-chain mono alkyl (methyl, ethyl or propyl) ester of fat acids obtained from renewable sources, like vegetable oil and animal fat. It has been used as an alternative fuel of Diesel cycle engines. It can be used blended with diesel oil or in the pure form, decreasing the use of petroleum derivates, resulting in a less environmental pollution, diminishing the green house effect. Biodiesel is obtained by transesterification reactions (alcoholysis of triglycerides with ethanol or methanol) of triacylglycerides, the main constituents of oil and fats, with alcohols and acids or alkalines catalysts. The main obtained products are the esters of fat acids and glycerol. The transesterification can be carried out under homogeneous or heterogeneous catalysis systems. The industry biggest challenge is to create a technological synthetic route that produces a pure product without causing a major environmental pollution. The aim of this work was to obtain sunflower biodiesel by transesterifications reactions carried out under homogeneous and heterogeneous catalysts. The transesterification reactions were performed by methyl and ethyl route, using as homogeneous catalysts, potassium hydroxide and as heterogeneous catalysts the ion exchange commercial resin Amberlyst 26
115

Fontes de lipídios poliinsaturados na nutrição e saúde da tilápia do nilo (oreochromis niloticus)

Araujo, Daniel de Magalhães [UNESP] 02 July 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-02Bitstream added on 2014-06-13T19:01:12Z : No. of bitstreams: 1 araujo_dm_dr_botfmvz.pdf: 484269 bytes, checksum: 933bc4b7d427c7cb581da5c913261ca6 (MD5) / Fundação de Amparo à Pesquisa do Estado de Alagoas (FAPEAL) / Universidade Estadual Paulista (UNESP) / Os ácidos graxos poliinsaturados (PUFAs) exercem importantes funções metabólicas no organismo animal, sendo indispensáveis ao crescimento e higidez em peixes. Foram avaliados os efeitos de diferentes relações entre PUFAs ômega-6 e ômega-3 sobre o desempenho, composição químico-bromatológica da carcaça e índices corporais de tilápias do Nilo. Foram utilizados alevinos revertidos (7,5g±0,21), distribuídos em 40 aquários, sendo oito peixes por aquário. Foram confeccionadas oito rações (tratamentos) experimentais: basal (sem adição de óleo); 6% de óleo de girassol (OG); 5% de OG + 1% de óleo de linhaça (OL); 4% de OG + 2% de OL; 3% de OG + 3% de OL; 2% de OG + 4% de OL; 1% de OG + 5% de OL; 6% de OL. O arraçoamento foi feito até aparente saciedade quatro vezes ao dia (8:30, 11:30, 14:30 e 17:30 horas). Ao final de 85 dias, foram determinados o peso final, ganho de peso, consumo alimentar aparente, conversão alimentar aparente, taxa de eficiência protéica, retenção de proteína e retenção de energia.Foram avaliados também a composição químico-bromatológica da carcaça, os índices corporais e a deposição de gordura visceral. Não houve efeito das dietas sobre o desempenho produtivo e composição corporal de tilápias do Nilo. Apenas a gordura visceral foi alterada dentre os índices corporais. Todas as relações entre PUFAs ômega-6 e ômega-3 proporcionaram desempenho zootécnico semelhante em tilápias do Nilo. Recomenda-se escolher a dieta de acordo com o custo de produção. / The polyunsaturated fatty acids (PUFAs) have indispensable metabolic function in fish growth and health. This study was set out to determine the effect of eight diets with different omega-6 and omega-3 PUFAs ratios in performance index, body chemical composition and body indexes of Nile tilapia juveniles. Fish (320 male of 7.50±0,21 g mean) were totally randomly distributed, with five replicates, into 40 plastic aquaria (250 L; 8 fish per aquarium). Eight diets were formulated: basal (with no oil supplementation); 6% sunflower oil (SO); 5% SO + 1% linseed oil (LO); 4% SO + 2% LO; 3% SO + 3% LO; 2% SO + 4% LO; 1% SO + 5% LO; and 6% LO. Fish were fed four times per day (8:30; 11:30; 14:30; and 17:30 hours) for 85 days. At the 85th day, performance index, body chemical composition and body indexes were evaluated. There were no significant differences in fish productive performance and body chemical composition. Visceral fat index in fish fed 6% oils diets contend were high. All diets provided equal tilapia growth performance.
116

Perfil de ácidos graxos e energia metabolizável aparente de diferentes fontes lipídicas para galinhas poedeiras / Fatty acid profile and apparent metabolizable energy of differents lipid sources for laying hens

Araujo, Robert Guaracy Aparecido Cardoso [UNESP] 17 January 2017 (has links)
Submitted by Robert Guaracy Aparecido Cardoso Araujo null (roberty_kadu@hotmail.com) on 2017-02-04T14:33:13Z No. of bitstreams: 1 Dissertação.pdf: 1123603 bytes, checksum: 04494f1c8cf34365a9d7ad9cb0ffd4de (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-02-07T13:05:58Z (GMT) No. of bitstreams: 1 araujo_rgac_me_dra.pdf: 1123603 bytes, checksum: 04494f1c8cf34365a9d7ad9cb0ffd4de (MD5) / Made available in DSpace on 2017-02-07T13:05:58Z (GMT). No. of bitstreams: 1 araujo_rgac_me_dra.pdf: 1123603 bytes, checksum: 04494f1c8cf34365a9d7ad9cb0ffd4de (MD5) Previous issue date: 2017-01-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / É importante a determinação atualizada dos valores nutricionais dos alimentos para a prática de formulação de rações para aves. O objetivo desta pesquisa foi avaliar o perfil de ácidos graxos e energia metabolizável aparente corrigida pelo balanço de nitrogênio (EMAn) de diferentes fontes de óleos (soja, girassol, linhaça e peixe) para galinhas poedeiras da linhagem Hysex White, com 24 semanas de idade. As dietas experimentais consistiram de: T1 – ração basal, T2 – ração basal + 10% de inclusão de óleo de soja, T3 – ração basal + 10% de inclusão de óleo de girassol, T4 – ração basal + 10% de óleo de linhaça e T5 – ração basal + 10% de óleo de peixe, distribuídas num delineamento inteiramente casualizado com sete repetições e oito aves por unidade experimental. O perfil de ácidos graxos das fontes lipídicas foi analisado por cromatografia gasosa. O ensaio de digestibilidade foi realizado pelo método de coleta total de excretas, utilizando-se 280 poedeiras em 35 gaiolas experimentais, incluindo aves do grupo controle. Os resultados foram submetidos à análise de variância e as médias dos tratamentos foram comparadas pelo teste de tukey à 5% de probabilidade. Os maiores níveis de ácidos graxos insaturados foram encontrados nas fontes de origem vegetal, com mais de 80% enquanto o óleo de peixe apresentou 58,38%. Os valores de EMAn na matéria natural foram: 9.334 kcal/kg para o óleo de soja; 10.533 kcal/kg para o óleo de girassol; 10.928 kcal/kg para o óleo de linhaça e 9.005 kcal/kg para o óleo de peixe. Os valores de EMAn entre as fontes lipídicas foram diferentes entre si, ressaltando a importância de haver uma matriz nutricional individual para cada óleo nos livros e tabelas sobre informações nutricionais dos ingredientes. / It is important to determine the current nutritional values of ingredients for the practice of feed formulations for birds. The objective of this research was to determine the fatty acid profile and evaluate the apparent metabolizable energy corrected for nitrogen balance (AMEn) of different lipid sources (soybean, sunflower, linseed and fish) for laying hens of Hysex White at 24 weeks of age. The experimental diets were: T1 – basal diet, T2 - basal diet + 10% soybean oil addition, T3 - basal diet + 10% sunflower oil addition, T4 - basal diet + 10% linseed oil and T5 - basal diet + 10% fish oil, in a completely randomized design with seven replicates with eight birds per experimental unit. The fatty acid profile of lipid sources was analyzed by gas chromatography. The digestibility trial was held by the total excreta collection method, using 280 birds in 35 experimental cages, including the birds of the control group. The results were submitted to analysis of variance and the means of treatments were compared by the tukey test at 5% probability. The highest levels of unsaturated fatty acids among the four lipid sources were found in sources of vegetable origin, with more than 80% while fish oil had 58.38%. The AMEn in natural matter were: 9.334 kcal / kg for soybean oil; 10.533 kcal / kg for sunflower oil; 10.928 kcal / kg for linseed oil and 9.005 kcal / kg for fish oil. The AMEn values among the lipid sources were different, emphasizing the importance of having an individual nutritional matrix for each oil in the books and tables on nutritional information of the ingredients. / FAPESP: 2015/14423-6
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Disponibilidade de níquel no sistema solo-planta: efeito de doses e saturações por bases / Nickel availability on soil-plant system: effects of Ni rates and saturations base

Fernando Giovannetti de Macedo 24 March 2016 (has links)
Por se tratar de um elemento essencial às plantas e um metal pesado ao mesmo tempo, o níquel requer atenção quanto aos aspectos da fisiologia de plantas e ambiental. Além disso, existe um intervalo estreito entre as exigências nutricionais e os teores tóxicos às plantas. Neste contexto, objetivou-se avaliar o efeito do Ni no sistema solo-planta, com foco no ciclo do N e a disponibilidade do elemento no solo, por meio de experimento em condições controladas, utilizando vasos distribuídos inteiramente ao acaso, utilizando-se esquema fatorial 2 x 5, com sete repetições cada tratamento. O primeiro fator foi constituído de duas saturações por base (50 e 70%) e o segundo de cinco doses de Ni (0; 0,1; 0,5; 1,0 e 10,0 mg dm-3 de solo). Os vasos foram preenchidos com 8 dm3 de terra e cultivados com soja [Glycine max (L.) Merrill] sucedida por girassol (Helianthus annuus L.). Os parâmetros qualitativos e quantitativos: altura de plantas (AP), diâmetro do caule (DC), número de nós (NN), estádio fenológico (EF), índice SPAD e, diâmetro do capítulo (DCap) (para girassol) foram avaliadas aos 30 e 60 dias após a emergência (d.a.e.) de cada cultivo. Plantas inteiras de soja, amostradas em quatro vasos de cada tratamento, foram coletadas no estádio R1. Na mesma ocasião foram coletadas amostras de solo da rizosfera. Em seguida, as plantas coletadas foram divididas em: folhas; raízes (nódulos na soja) e parte aérea. Foram determinados nas folhas utilizadas para diagnose em soja e girassol: os teores de macro e micronutrientes, as atividades da redutase do nitrato e da urease e as concentrações dos ácidos orgânicos: oxálico, malônico, succínico, málico, tartárico, fumárico, oxaloacético, cítrico e lático. Os mesmos ácidos orgânicos foram determinados em raízes secundárias de girassol e nódulos de soja. Foram realizadas avaliações ultraestruturais por meio de microscopia eletrônica de transmissão (MET) em raízes de girassol, e estruturais e de tonalidade em nódulos de soja, por meio de microscopia de luz. No solo, foram determinadas: atividade urease, desidrogenase, Ni total e fitodisponível pelos métodos: Mehlich-1, Mehlich-3 e DTPA. No período de maturidade fisiológica de cada cultura foi realizada a colheita das plantas dos vasos restantes para determinação de produção de grãos, teores de Ni na planta inteira e Ni e N nos grãos. Ao final dos dois experimentos foi realizada nova coleta de solo para extração sequencial de Ni. O índice SPAD em soja aos 60 d.a.e., a produção de massa seca da parte aérea da soja e da raiz de girassol foram influenciados pela saturação por bases, doses de níquel e pela a interação destes. Foram influenciados pelas saturações por base e doses de níquel (fatores isolados): para soja: AP aos 60 d.a.e., NN aos 30 e 60 d.a.e., SPAD aos 30 d.a.e.; para girassol: AP e NN aos 30 e 60 d.a.e., DC e SPAD aos 30 d.a.e. As demais variáveis avaliadas aos 30 e 60 d.a.e. foram influenciadas apenas pela saturação por bases, ou doses de Ni separadamente. As plantas de soja e girassol apresentaram maiores teores de Ni nos diferentes tecidos avaliados (exceto grãos) quando cultivadas sob V50%. A produção de grãos de soja e girassol não foi influenciada pelos tratamentos, porém o teor de N dos grãos de soja influenciado pelas doses de Ni na V70%. A atividade da enzima urease nas folhas de soja e girassol foi responsiva positivamente ao aumento das doses de Ni. Quatro dos ácidos orgânicos avaliados e o teor de N nas folhas e nos grãos foram maiores nas plantas cultivadas sob V70% com a dose de 0,5 mg dm-3 de Ni. As doses de Ni bem com as saturações por bases influenciaram diretamente o balanço de nutrientes das plantas. Os extratores Mehlich-1, Mehlich-3 e DTPA apresentaram elevado coefienciente de correlação entre a fração de Ni disponível no solo e a concentração do elemento nas plantas de soja e girassol, sendo o extrator DTPA o que apresentou maior coeficiente de correlação. O Ni apresentou distribuição variável entre as diferentes frações do solo em função dos tratamentos. Os solos dos tratamentos com saturação por bases de 70% apresentaram maior concentração de Ni ligado a carbonato, comparado aos tratamentos sob saturação por bases de 50%. A distribuição do Ni entre as frações do solo seguiu a seguinte orgem: ligado a carbonato < trocável < ligado a óxidos < matéria orgânica < residual. A saturação por bases exerceu efeito diferenciado para a atividade da urease no solo em função da cultura avaliada. Por sua vez, o Ni exerceu efeito diferenciado sobre a atividade de desidrogenase em função da cultura estudada / As an essential element for plants and a heavy metal at the same time, nickel requires attention on the aspects of the physiology of plants and environmental. Furthermore, there is a narrow range between nutritional requirements and toxic levels to plants. In this context, the aim was to evaluate the effect of Ni in soil-plant system through experiment under controlled conditions, using soil pots distributed entirely at random, using a factorial 2 x 5, with seven repetitions each treatment. The first factor was formed of two saturations base (50 and 70%) and the second of five Ni rates (0, 0.1, 0.5, 1.0 and 10.0 mg dm-3 of soil). The pots were filled with 8 dm3 of soil and sown with soybean [Glycine max (L.) Merrill] succeeded by sunflower (Helianthus annuus L.). The agronomic traits: plant height (PH), stem diameter (SD), number of nodes (NN), phenological stage (PS), SPAD index, head diameter (HD) (Sunflower) were evaluated at 30 and 60 days after emergence (dae) of each crop. Whole soybean plants, sampled in four pots of each treatment were collected at the R1 stage for analysis of soil samples from the rhizosphere. Then, the collected plants were divided into: sheets; roots (nodules on soybean) and shoot. Were determined in the leaves used for diagnosis in soybean and sunflower: macro and micronutrients, activities of nitrate reductase, and urease and concentrations of organic acids: oxalic, malonic, succinic, malic, tartaric, fumaric, oxaloacetic, citric and lactic. The same organic acids were determined in secondary roots of sunflower and nodules of soybean. They were conducted ultrastructural evaluations by means of transmission electron microscopy (TEM) in sunflower roots, and color in soybean nodules, using light microscopy. In the soil were determined: urease activity dehydrogenase, the total Ni and available by methods: Mehlich-1, Mehlich-3 and DTPA. At physiological maturity period of each culture was performed to harvest the plants of other pots in order to determine grain dry matter yield, Ni content in the whole plant and Ni and N content in grains. At the end of the two experiments it were carried out new soil sampling for Ni sequential extraction. The SPAD index taken on soybean leaves at 60 d.a.e., the dry matter production of the aerial part of soybean and sunflower root were influenced by the base saturation, nickel doses and the interaction among them. They were influenced by the saturation for base and nickel doses (single factor): soybean: HP d.a.e. to 60, NN at 30 and 60 d.a.e., SPAD to 30 d.a.e.; Sunflower: PH and NN at 30 and 60 d.a.e., HD and SPAD to 30 d.a.e. The other variables assessed at 30 and 60 d.a.e. They were influenced only by base saturation, or Ni doses separately. Sunflower soybean plants had higher Ni contents at the different tissues (except grain) when grown under V50%. The production of soybean and sunflower grains was not affected by the treatments, but the N content of the soybeans was changed by Ni rates V70%. The urease enzyme activity in soybean and sunflower leaves was responsive to increased doses of Ni. Four of the organic acids and the N content in leaves and grains were higher in plants grown under V70% at the dose of 0.5 mg dm-3 Ni. Ni rates as well as the cation base saturation directly influenced the balance of plant nutrients. The Mehlich-1, Mehlich-3 and DTPA presented higher coefiencient correlation between available Ni soil fraction with nutrient concentrations in both soybean and sunflower, with the DTPA solution showing the highest correlation coefficient in this analysis. Ni showed variable distribution among different soil fractions in the treatments. The treatments presented soil under cation bases saturation of 70% showed higher Ni concentration linked to carbonate, as compared to treatments under cation base saturation of 50%. The distribution of Ni between the soil fractions followed the following order: bound to carbonate <exchangeable < bound to oxides <organic matter <residual. The cation base saturation showed different effects on the urease activity according to the plant evaluated. Ni exerted on the differential effect dehydrogenase activity according to the plant specie
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Aplica??o de metodologias pedag?gicas utilizando a irriga??o como instrumento no processo de ensino-aprendizagem: estudo de caso no IFS / Irrigation as instrument in the teach-learning process. Study of Case: Instituto Federal de Educa??o, Ci?ncia e Tecnologia de Sergipe ? IFS/Campus S?o Crist?v?o.

Oliveira, Jac? Ara?jo de 08 December 2009 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-09-12T11:45:07Z No. of bitstreams: 1 2009 - Jac? Ara?jo de Oliveira.pdf: 4244721 bytes, checksum: 02cc9649b101c305bf9e67e48d13be0b (MD5) / Made available in DSpace on 2018-09-12T11:45:07Z (GMT). No. of bitstreams: 1 2009 - Jac? Ara?jo de Oliveira.pdf: 4244721 bytes, checksum: 02cc9649b101c305bf9e67e48d13be0b (MD5) Previous issue date: 2009-12-08 / Ahead of the recent and accented technological scientific innovations that play a significant role in the society, either in the politics, in the economy, in the culture or in the education, it is need to redefine the educational practices. In this context, it was objectified to evaluate the performance of the 3rd grade students in the Integrated Technical Course on Agricultural, applying the traditional pedagogy methods and the project pedagogy methods, using as instrument the aspersion irrigation systems, dripping and microaspersion, in the sunflower culture (Helianthus annus L). The present work was developed in 2008, in IFS/Campus S?o Crist?v?o, in S?o Crist?v?o city-SE. It were selected the classes A and C of the 3rd grade, with 28 students each ones, in a random drawing, so the class C was contemplated with the project pedagogy. Initially a first questionnaire was applied to the 56 students that contain questions about irrigation and sunflower culture. Six months after be taught theoretical and practical lessons, it was repeated the first questionnaire. The didactic activities had continued for more six months and, after this period, it was applied the second questionnaire that contend questions about irrigation emphasizing hydraulic. The data had been priced and analyzed statistically by test t with 5% of probability. It was made the first questionnaire application, and the classes A and C have average 6.8 and 6.3, respectively, being statistically equal to the research continuity. On the other hand, when the first questionnaire was applied again, the class C students obtained notes statistically higher when it was compared with the class A students (8.6 and 6.0). The statistics superiority of the class C notes was maintained when the second questionnaire was applied (6.5 and 3.0), proving that the project pedagogy provides a better learning. It is concluded that the project pedagogy is superior to the traditional pedagogy, not only by the grades, but also by the different behavior observed in the students, that were more participatory, questioning and critical. / Diante das recentes e acentuadas inova??es cient?ficas e tecnol?gicas que na sociedade desempenham papel expressivo, seja na pol?tica, na economia, na cultura ou na educa??o, urge redefinir pr?ticas pedag?gicas. Neste contexto, objetivou-se avaliar o desempenho dos alunos da 3?. s?rie do Curso T?cnico Integrado em Agropecu?ria, aplicando-se as metodologias das pedagogias tradicional e de projetos, por interm?dio da utiliza??o dos sistemas de irriga??o por aspers?o, gotejamento e microaspers?o, na cultura do girassol (Helianthus annus L). O presente trabalho foi desenvolvido no ano de 2008, no IFS/Campus S?o Crist?v?o, no munic?pio de S?o Crist?v?o ? SE. Foram selecionadas as turmas A e C da 3? s?rie, com 28 alunos cada, e em sorteio aleat?rio, a turma C foi contemplada com a Pedagogia de Projetos. Inicialmente foi aplicado aos 56 alunos um primeiro question?rio contendo quest?es da ?rea de irriga??o e da cultura do girassol. Seis meses depois de ministradas aulas te?ricas e pr?ticas, repetiu-se o primeiro question?rio. As atividades did?ticas continuaram por mais dois meses e, ap?s esse per?odo, aplicou-se um segundo question?rio contendo quest?es de irriga??o com ?nfase em hidr?ulica. Os dados foram tabelados e analisados estatisticamente pelo teste t ao n?vel de 5% de probabilidade. Feita a aplica??o do primeiro question?rio, as turmas A e C apresentaram m?dias 6.8 e 6.3, respectivamente, estatisticamente iguais para a continuidade da pesquisa. Por outro lado, quando o primeiro question?rio foi novamente aplicado, os alunos da turma C obtiveram notas estatisticamente superiores aos da turma A (8.6 e 6.0). A superioridade estat?stica das notas da turma C manteve-se quando se aplicou o segundo question?rio (6.5 e 3.0), comprovando que a Pedagogia de Projetos proporciona uma melhor aprendizagem. Conclui-se que esta pedagogia ? superior ? tradicional, n?o somente pelas notas obtidas, mas tamb?m pelo comportamento diferenciado observado nos alunos, que se mostraram mais participativos, questionadores e cr?ticos.
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Uticaj dodatka biljnih proteinskih koncentrata u hranu za životinje na kvalitet peleta / The effect of addition of plant protein concentrates in animal feed on pellet quality

Čolović Radmilo 19 July 2013 (has links)
<p>Suncokretova sačma ima manju zastupljenost u peletiranim sme&scaron;ama za<br />ishranu životinja od sojine sačme zbog većeg udela sirovih vlakana. Sirova<br />vlakna depresivno deluju na svarljivost obroka i proizvodne rezultate, a mogu<br />da imaju negativan uticaj na fizički kvalitet peleta. Pri peletiranju sme&scaron;a za<br />ishranu životinja u poslednje vreme značajna pažnja se posvećuje<br />funkcionalnim promenama makronutrijenata, jer se smatra da ove promene<br />pozitivno utiču na fizički kvalitet peleta. Razvojem modernih analitičkih tehnika,<br />posebno termalne analize, moguće je opisati promene na skrobu u procesu<br />peletiranja, nastale usled uticaja toplote i vlage. Sa druge strane, promene na<br />proteinskoj komponenti u procesu peletiranja nisu dovoljno obja&scaron;njene.<br />Najče&scaron;će se tumačenja svode na pretpostavke, bez obja&scaron;njenja o promenama<br />u veličini molekula proteina, kao i njihovoj koncentraciji. Inovativan pristup ove<br />doktorske disertacije je usmeren na opisivanje uticaja dodatka sojine i<br />suncokretovih sačmi različitog sadržaja proteina u sme&scaron;e na bazi kukuruza na<br />tehnolo&scaron;ke parametre procesa peletiranja, funkcionalne promene<br />makronutrijenata (želatinizaciju skroba i denaturaciju i degradaciju proteina) i<br />fizički kvalitet peleta. U okviru svake sme&scaron;e takođe je ispitivan uticaj procesnih<br />parametara, prečnika otvora sita mlina čekićara (2, 3 i 4 mm), vremena<br />produženog kondicioniranja parom (bez produženog kondicioniranja, 5 i 10<br />minuta) na fizički kvalitet peleta. Istraživanja su pokazala da temperatura<br />peletiranja, specifična potro&scaron;nja električne energije i udeo pra&scaron;ine u peletama<br />zavise od sirovinskog sastava sme&scaron;a, prečnika otvora sita mlina čekićara i<br />vremena zadržavanja u kondicioneru, pri čemu temperatura peletiranja i<br />specifična potro&scaron;nja električne energije rastu, a udeo pra&scaron;ine u peletama<br />opada sa porastom koncentracije proteina u sme&scaron;ama. Dokazano je i da<br />proces peletiranja utiče na funkcionalne promene makronutrijenata,<br />želatinizaciju skroba i strukturne promene na proteinima. Takođe je dokazano i<br />da za optimalno vreme zadržavanja materijala u kondicioneru, smanjenje<br />prečnika otvora sita mlina čekićara i povećanje sadržaja proteina u sme&scaron;ama<br />utiču na pobolj&scaron;anje fizičkog kvaliteta peleta, tj. tvrdoće peleta i stepena<br />otiranja peleta. Optimalni uslovi procesa peletiranja određeni su metodom<br />željene funkcije. Dat je predlog opsega procesnih parametara za dobijanje<br />peleta minimalnog stepena otiranja uz optimalnu specifičnu potro&scaron;nju<br />električne energije.<br />Istraživanja u ovoj doktorskoj disartaciji dala su doprinos novim saznanjima o<br />uticaju dodatka sačme različitog sadržaja proteina (37,3, 40,3 i 42,6 %) na<br />fizički kvalitet peleta. Kvalitet peleta sa dodatkom suncokretove sačme je<br />poređen sa kvalitetom peleta sa dodatom sojinom sačmom, kao i kvalitetom<br />peleta od čistog kukuruza, u cilju obja&scaron;njenja uticaja izvora i koncentracije<br />proteina. Ispitivanja su vr&scaron;ena ne samo za standardno vreme kondicioniranja,<br />nego uz primenu najsavremenijih postupaka termičke obrade hrane za<br />životinje, tj. uz upotrebu produženog kondicioniranja od 5 i 10 minuta.<br />Doprinos nauci je dat i time &scaron;to je pokazano da proces peletiranja utiče ne<br />samo na denaturaciju i degradaciju proteina, nego i na njihovo povezivanje.</p> / <p>Sunflower meal has a lesser presence in pelleted compound feed than<br />soybean meal due to a higher proportion of raw fiber. Raw fiber has<br />depressing effect on the digestibility and production results, and can have a<br />negative impact on the physical quality of the pellets. Lately, considerable<br />attention is paid to the functional changes of macronutrients in pelleting of<br />animal feed. It is believed that these changes have a positive impact on the<br />physical quality of the pellets. With the development of modern analytical<br />techniques, especially the thermal analysis, it is possible to describe the<br />changes of starch in pelleting process, caused by the impact of heat and<br />moisture. On the other hand, changes of the protein components in the<br />pelleting process are not sufficiently explained. The most common<br />interpretation is reduced to the presumption, with no explanation of changes in<br />the size of protein molecules, as well as in their concentration. The innovative<br />approach of this dissertation is focused on describing the effect of the addition<br />of soybean meal and sunflower meals, with different protein content, in<br />mixtures based on corn, on the technological parameters of the pelleting<br />process, functional changes of macronutrients (starch gelatinization, and<br />protein denaturation and degradation), and physical quality of the pellets.<br />Within each of the mixtures, the influence of process parameters, the diameter<br />of the hammer mill sieve openings (2, 3 and 4 mm), duration of long term<br />steam conditioning (without extended conditioning, 5 and 10 minutes) on the<br />physical quality of the pellets was also investigated. Studies have shown that<br />pelleting temperatures, the specific power consumption and the proportion of<br />dust in pellets were dependent of composition of the mixtures, the diameter of<br />the hammer mill sieve openings, and residence time in the conditioner.<br />Pelleting temperature and specific power consumption increased, and the<br />extent of fines in pellets decreased with increasing of concentration of protein<br />in the diets. Additionally, it is proved that pelleting process affects functional<br />changes of macronutrients, starch gelatinization and structural changes in<br />proteins. It is also proved that for the optimal retention time of material in<br />conditioner, decrease of diameter of the hammer mill sieve openings and<br />increase of protein content in the diets had positive effect on the physical<br />quality of pellets, i.e. pellet hardness and degree of abrasion of pellets. The<br />optimum process conditions in pelleting process were determined by the<br />method of desired function. A proposal has been made for setting the range of<br />process parameters for obtaining the minimum degree of abrasion of pellets,<br />with optimal specific energy consumption.<br />The research within this Ph.D. thesis contributed to the knowledge about the<br />effects of addition of sunflower meal with different protein content (37.3, 40.3<br />and 42.6 %) on the physical quality of the pellets. Quality of pelleted mixtures<br />with sunflower meal added were compared with the quality of pelleted mixtures<br />with soybean meal added and quality of pelleted corn, in order to explain the<br />effects of starch concentration, protein concentration and protein source.<br />Studies were performed not only for the standard time of conditioning, but with<br />the use of modern techniques for heat treatment of animal feed, i.e. with the<br />use of long term conditioning process for a 5 or 10 minutes. Additional<br />contribution to science has been given with showing that the pelleting process<br />causing not only the denaturation and degradation of proteins, but also<br />synthesis of proteins.</p>
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Mechanised Intercropping and Double Cropping in Southern Queensland

Peter Michael Masasso Unknown Date (has links)
The potential for relay intercropping and double cropping was assessed in field trials over three consecutive years at Gatton, Queensland. The rationale was to use controlled traffic technology to facilitate relay and double cropping and thus research a cropping system that could exploit late winter crop rainfall. In Field Trial I, grain sorghum and sunflower, broadacre crops already grown within the Southern and Darling Downs regions of Queensland and New South Wales were intercropped into wheat; sunflower was intercropped with wheat in Field Trial II. Sole summer plantings were made at the same time as intercrops were planted. The wheat crop was cut and stubble removed to facilitate this. Various planting dates (three for Field Trial I; four for Field Trial II) for the relayed summer crops were used to determine if an optimum planting time existed. Plant height, tiller number, light interception, grain yield, soil moisture and economic return were used as parameters to compare the intercrop with sole plantings in Field Trial I. Grain yield, soil moisture, rainfall infiltration and economic return were measured in Field Trial II. Research also involved the modification and testing of a tractor to carry out the sowing of the intercrop. In Field Trial I, light interception was shown to vary at different stages of the wheat crop and the use of these stages to determine optimum planting dates of the relay crop is suggested. In both trials, no differences were recorded in the grain yield between intercropped and sole cropped wheat treatments suggesting the trafficking of the plot did not affect the wheat. As neither sorghum or sunflower established as intercrops, competition was not a factor in affecting wheat yields. Moisture readings in both trials showed little change below a depth of 100 cm; however some treatment differences were present at shallower depths. In Field ii Trial I, sole summer sorghum, especially the first planting date, showed reduced water capture/ higher soil evaporation due to wheat removal initially and later transpiration loss due to crop growth and increased weed pressure. Sole wheat treatments showed increased moisture storage after harvest due to lack of water use by the crop and increased infiltration/reduced runoff due to stubble retention. Improved soil moisture recharge after rainfall events was apparent in double cropped treatments suggesting not only improved water utilisation but also improved capture and storage is possible within this system. Sorghum, commonly used throughout south eastern Queensland as a summer crop option, proved unsuitable for relay intercropping in Field Trial I for Planting Dates 1 and 2. Minimum soil temperatures for these plantings were marginal as they were close to the 15o Celsius level recommended for sorghum. However, even though establishment was poor for the intercropped plantings, it was higher for sole sorghum plantings. Wheat allelopathic effects may be involved. To avoid the temperature limitations of sorghum, sunflower was selected as an alternative intercrop in the later planting dates of Field Trial I and all dates for Field Trial II. Reasons for the poor establishment and yield of sunflowers in the earlier intercrop planting dates compared to sole plantings remain unknown but also may be related to allelopathic effects from intercropped wheat. Low soil temperature was not a factor affecting establishment Yields for planting dates were recorded in the intercropped sunflower treatments for Field Trial II and the optimal planting time for sunflowers in a wheat/sunflower relay intercrop was identified as when physiological maturity of the wheat had occurred. This may relate to the wheat crop stage. In Field Trial II, no significant differences in soil moisture were recorded between treatments from overall water use for the trial period. There were differences in water use between intercropped and sole cropped treatments for iii some rainfall events. Three rainfall events were chosen for closer study in each of the field trials conducted. Each event varied in the length and time as well as the duration and intensity of the rain that fell for the period. For the first rainfall period the moisture content of the first planting date of the sole summer treatment and to a lesser extent the second planting date of the same treatment increased, most likely due to wheat removal. In the third rainfall period the double cropped sunflower treatment with stubble tended to store less moisture and this may be due to the active crop growth at this time. It was evident in both field trials of the need for an effective weed control program in the intercrop plots. Weeds were controlled in wheel tracks by glyphosate sprays. Cultural methods may help but a herbicide suitable for both components of the intercrop would be very useful. A tractor was successfully modified to a 3 metre wheelspace and a clearance of 70 cm. This proved sufficient for planting the relay intercrop in Field Trial II without negatively affecting the yield of the standing crop. The row spacing of 18 cm for wheat in a 3 metre fixed bed and wheeltrack configuration assisted with guidance and interplanting of the relay crop. The relay crop was sown as single alternating rows.

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