Made available in DSpace on 2014-06-11T19:30:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-10-10Bitstream added on 2014-06-13T19:00:35Z : No. of bitstreams: 1 foloni_jss_dr_botfca.pdf: 804895 bytes, checksum: eed8c0d64df6ac23a2b7d1aa9d626398 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Objetivou-se com este trabalho avaliar a dinâmica do potássio no sistema solo-palha-planta, com a rotação das culturas milheto, soja e aveia preta conduzidas em semeadura direta, em função do manejo da adubação potássica ao longo de três anos agrícolas. O experimento foi conduzido na Fazenda Experimental Lageado da FCA/UNESP, em Botucatu-SP, nos anos agrícolas de 2000/2001, 2001/2002 e 2002/2003. O solo foi classificado como Latossolo vermelho distroférrico de textura média (770 g kg-1 de areia, 210 g kg-1 de argila e 20 g kg-1 de silte). A área vinha sendo cultivada com soja em semeadura direta por um ano agrícola antes da instalação do experimento. No primeiro ano de condução do experimento, o milheto (Pennisetum glaucum, var. BN-2) foi semeado em Setembro/2000, sobre a palha de aveia preta (Avena strigosa). A adubação nesta semeadura foi de 20 kg ha-1 de P2O5 (Superfosfato Simples) e 15 kg ha-1 de N (Nitrocálcio). O milheto foi dessecado por ocasião da semeadura da soja (Glycine max L. Merrill, var. IAC-17), que foi semeada em Dezembro/2001, com 60 kg ha-1 de P2O5 . Em Abril/2001, fez-se a semeadura da aveia preta sem o uso de fertilizantes. A aveia preta foi dessecada na semeadura do milheto (Setembro/2001), que por sua vez foi dessecado na semeadura da soja (Dezembro/2001). As adubações do milheto e da soja foram as mesmas utilizadas no ano anterior. O delineamento experimental foi em blocos ao acaso, num esquema fatorial 4 x 4 ( 0, 30, 60 e 90 Kg ha-1 de K2O aplicados na semeadura do milheto x 0, 30, 60, 90 Kg ha-1 de K2O aplicados na semeadura da soja), constituindo 16 tratamentos, com quatro repetições. A palha da superfície do solo foi coletada na semeadura do milheto, na semeadura da soja, e aos 25, 50, 75 e 100 dias após a emergência da soja (DAE da soja), nos dois primeiros anos agrícolas. O solo foi coletado nas mesmas épocas de coleta... / The objective of this experiment was to study the potassium dynamics in no-tillage system, crop development and soybean yields, in different rates of potassic fertilization. The experiment was carried out in Fazenda Experimental Lageado in FCA/Unesp, in São Paulo state, Brazil, for 3 years. The soil was classified like Latossolo red distroférrico with medium texture (770 g kg-1 of sand, 210 g kg-1 of clay and 20 g kg-1 of silt ). The area had been cropped to soybean in no-tillage for one year before the experiment. In the first year, Pearl millet (Pennisetum glaucum, var. BN-2) was planted in September, over black oat (Avena strigosa) straw, receiving 20 kg ha-1 of P2O5 (Simple super phosphate) and 15 kg ha-1 of N (Calcium Nitrate). earl millet was desiccated at the same time that soybean (Glycine max L. Merrill, var. IAC-17) was planted, in December/2001, using 60 kg ha-1 of P2O5. In Abril/2001, black oat was planted without fertilizers. Black oat was desiccated at the same time that Pearl millet was planted (September/2001), and was desiccated at the next soybean planting (December/2001). Pearl millet and soybean fertilizations were the same as those used in the previous year. The experiment was carried out in a 4 x 4 factorial design with randomized complete blocks (0, 30, 60 and 90 Kg ha-1 of K2O applied at Pearl millet planting x 0, 30, 60, 90 Kgha-1 of K2O applied to soybean), with four replications. The soil surface straw was collected at Pearl millet planting and at soybean planting, at 25, 50, 75 and 100 days after soybean emergence (DAE), in both years. Soil samples were taken at the same times as straw samplings, in the layers 0-5, 5-10, 10-20, 20-40 and 40-60 cm deep, in both years. Soybean shoots were collected at 25, 50, 75 and 100 DAE, in both years. Roots were sampled at 50 DAE, in the same depths as soil was sampled. At harvest yields were determined... (Complete abstract click electronic access below)

Orientador: Antonio Baldo Geraldo Martins / Coorientador: Manoel Evaristo Ferreira / Banca: Aparecida Conceição Boliani / Banca: Adriana de Castro Correia da Silva / Banca: Rita de Cássia Panizzi / Banca: Mara Cristina Pessôa da Cruz / Resumo: O plantio de abacaxi no Brasil é direcionado para o consumo in natura. Produzido principalmente no Norte e Nordeste, as variedades mais plantadas é o Pérola (com mais de 80% da área produzida) e o Smooth Cayenne. Este estudo evidenciou o efeito de diferentes densidades e doses de potássio na planta e no fruto de abacaxi Pérola em sistema irrigado, no Tocantins. O delineamento fez-se em blocos casualizados com parcelas subdivididas com quatro repetições. Os tratamentos principais constitui-se das doses de K (0, 8, 16 24 e 32 g planta - 1 de K2O) e os tratamentos secundários compostos das densidades de plantio que diferenciaram o espaçamento de plantas na mesma linha (30, 40, 50 e 60 cm). O plantio foi realizado em linhas duplas utilizando irrigação por gotejamento e as adubações de K executadas por fertirrigação. Avaliou- se a folha "D" do abacaxizeiro (comprimento, massa fresca da folha, composição mineral) e dos frutos (massa fresca com coroa, sem coroa e produtividade). Verificou-se que a folha "D" estava acima de 90 g e com mais de 100 cm, após 10 meses do plantio, estando apta a indução floral, concluindo-se que os tratamentos não interferiram no desenvolvimento do abacaxizeiro. Na avaliação química da folha "D", houve significância na concentração de K, conforme se aumentou a dose de K no solo. Assim, as doses de K influenciaram na massa fresca do fruto sem coroa. As diferentes densidades influenciaram na massa fresca do fruto com e sem coroa e na produtividade. Portant... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The pineapple planting in Brazil is destined for fresh consumption. Produced mainly in the North and Northeast, the most planted varieties is the Pérola (with over 80% of the area produced) and the Smooth Cayenne. This study showed the effect of different densities and potassium levels in plant and pineapple fruit (Pérola) in the irrigation system in the Tocantins. The project was done in blocks with parcels subdivided design with four replications. The main treatments are K doses (0, 8, 16 24 and 32 g plant - 1 K2O) and compound secondary treatments of population densities that differentiated the spacing between plants on the same line (30, 40, 50 and 60 cm). The seedlings were planted in double rows using drip irrigation and fertilization of K performed by fertigation. Was evaluated sheet "D" pineapple (length, fresh weight of leaf mineral composition) and fruit (fresh pasta with the crown without crown and productivity). It was found that the "D" sheet was above 90 g and over 100 cm after 10 months of planting, before floral induction, concluding that the treatments did not affect the development of pineapple. In the chemical evaluation of "D" sheet had a significant concentration of K with increasing dose of K in the soil. Thus, the amount of K influences the fresh weight of fruit without a crown. The different densities influenced the mass of fresh fruits with and without crown and productivity. Therefore, the range Pérola can be used for densification up to 41,000 plants ha-1 without altering the desired main characteristic as well as obtaining fruit above 1500 g using 8 g plant - 1of K2O fertigation / Doutor

Un approvisionnement stable en fourrage est important pour la pérennité des fermes laitières dans l'Est du Canada. En plus de l'azote, la croissance optimale des cultures fourragères nécessite un apport adéquat en potassium (K) et en phosphore (P), dont la disponibilité pourrait être influencée par les pratiques culturales. L'objectif principal de cette thèse était d'évaluer la stabilité des rendements fourragers sous des pratiques culturales contrastées, mais également de comprendre comment ces pratiques influent sur la dynamique du K et du P dans un sol argileux de l'Est canadien. Un dispositif de longue durée a été initié en 1989 dans la région du Saguenay Lac St-Jean. Il s'agissait d'une rotation fixe orge-fourrage-fourrage établie sur un Gleysol humique sous labour conventionnel (MP) ou chisel (CP) et recevant une fertilisation minérale (MIN) ou organique (fumier liquide de bovins laitiers, LDM). Nous avons identifié que les rendements étaient plus stables cycliquement (par cycle de trois ans) qu'annuellement. L'indice de stabilité du rendement a été réduit d'un facteur de 1.86 ± 0.57 pour les grains, de 1.87 ± 0.24 pour les pailles et de 2.00 ± 0.25 pour les fourrages en utilisant l'évaluation cyclique. Le LDM a permis d'obtenir des rendements en fourrage et en paille plus élevés que MIN. Cependant, le travail du sol n'a pas influencé les rendements. Le bilan cumulé de K était en moyenne de −579 kg K ha⁻¹ cycle⁻¹ avec MIN et +69 kg K ha⁻¹cycle⁻¹ avec LDM. L'accumulation de K échangeable dans les couches supérieures du sol était plus élevée avec LDM qu'avec MIN. Toutefois aucune relation significative entre le bilan cumulé de K et le K échangeable n'a été observée à travers les cycles. Les fractions de K échangeable et non échangeable entre 2001 et 2016 ont augmenté avec MIN malgré un bilan K déficitaire, mettant en évidence l'équilibre dynamique entre les formes de K du sol. Pour le P, le bilan cyclique cumulé variait de –20 à +150 kg P ha⁻¹ avec LDM, et de –33 à +3 kg P ha⁻¹ avec MIN, alors que des réserves plus élevées de P Mehlich-3 ont été mesurées dans la couche arable (0–15 cm) avec MIN qu'avec LDM. Une relation négative entre le bilan cumulé de P et le P Mehlich-3 a été observée soulignant la complexité des mécanismes contrôlant la disponibilité du P dans le sol. L'analyse de la couche 0–15 cm avait montré un P total plus faible sous LDM par rapport à MIN pour deux dates (2001 et 2016), et une diminution de P organique entre 12 et 27 ans sous LDM probablement due à une minéralisation ou à une perte de P organique. Les résultats obtenus avaient également montré que le travail du sol a eu un effet significatif sur la répartition de K et de P dans le sol. En raison de la différence de profondeur de labour entre CP (15 cm) et MP (20 cm), le CP avait conduit à une plus grande accumulation de K et de P dans la couche 0−15 cm, tandis que l'inverse a été constatée dans la couche 15−30 cm. Les résultats semblaient également indiquer qu'un prélèvement de K et de P par les plantes a eu lieu dans la profondeur 15−30 cm. Dans l'ensemble, cette étude a permis de démontrer que la stabilité cyclique des rendements ouvrait une nouvelle perspective de gestion des terres et de stockage des foins et de souligner la forte capacité tampon en K et en P des sols à texture fine. Avec un suivi régulier des cultures, et du statut potassique et phosphaté du sol, le CP et le LDM pourraient assurer la durabilité des systèmes fourragers dans l'Est du Canada. Toutefois, l'approche reliant les bilans de K et de P à leurs formes disponibles pour soutenir le concept d'accumulation et de maintien de la fertilité du sol s'est révélée peu fiable dans ce sol argileux. Enfin, nous recommandons de revisiter localement la stratégie de fertilisation des systèmes fourragers composés de légumineuses et de graminées établis sur un Gleysol humique afin d'inclure la teneur en K non échangeable dans la recommandation en K et la teneur en argile du sol dans la recommandation en P. / A stable supply of forages is important to ensure sustainability of the dairy farms in Eastern Canada. In addition to nitrogen, optimal forage growth requires an adequate supply of potassium (K) and phosphorus (P), whose availability could be influenced by agricultural practices. The main objective of this thesis was to assess forage yields stability under contrasting management practices, but also to understand how these practices influence K and P dynamics in clayey soils of Eastern Canada. We used along-term experiment established in 1989 in the region of Saguenay Lac St-Jean. This was a fixed barley-forage-forage rotation established on a humic Gleysol under moldboard plow (MP) or chisel (CP) plowing and supplied by mineral (MIN) or organic (liquid dairy manure, LDM) fertilizers. We found that crop yields were more stable cyclically (per three-year cycle) than annually. Yield stability index was reduced by factor of 1.86 ± 0.57 for grains, 1.87 ± 0.24 for straw and 2.00 ± 0.25 for forage using cyclic assessment. The LDM returned higher forage and straw yields than MIN. However, yields were not influenced by the tillage practice. Cumulative K budget averaged −579 kg K ha⁻¹ cycle⁻¹ with MIN and +69 kg K ha⁻¹ cycle⁻¹ with LDM. Exchangeable K accumulation in upper soil layers was higher with LDM than MIN. Nevertheless, no significant relationship between cumulative K budget and exchangeable K was observed across cycles. Exchangeable and non-exchangeable K fractions between 2001 and 2016 increased under MIN (deficit K budget), underlying the dynamic equilibrium between soil K forms. For P, cumulative cyclic budget varied from –20 to +150 kg P ha⁻¹ with LDM, and –33 to +3 kg P ha⁻¹ with MIN, while higher reserves of Mehlich-3 P were measured in topsoil (0–15 cm) with MIN than LDM. The negative relationship between cumulative P budget and Mehlich-3 P highlighted the complex mechanisms controlling soil P availability. Soil analysis in 0–15 cm layer showed lower total P with LDM than MIN for two dates (2001 and 2016), and a decline of organic P between 12 and 27 years under LDM probably due to organic P mineralization or loss. Tillage practices had significant effect on soil K and P distribution. Due to the difference in plowing depth between CP (15 cm) and MP (20 cm), the CP led to greater K and P accumulation than MP in the 0−15 cm layer, while the reverse was observed in 15−30 cm layer. The results also indicated that K and P uptakes by plants occurred in the 15−30 cm depth. Overall, this study showed that cyclic yield stability opened up a new perspective for land allocation and forage storage, and underlined the high buffer capacity in K and P of fine-textured soils. With regular monitoring of crops, and soil K and P status, CP and LDM could ensure the sustainability off orage production systems in Eastern Canada. However, the approach relating K and P budget to their available forms to support soil fertility buildup and maintenance appeared to be wrong in this clayey soil. Finally, we suggest to revisit local fertilization strategy of forage legume and grass mixtures in rotation with cereal established on a humic Gleysol in order to include non-exchangeable K content in K fertilizer recommendation and soil clay content in P fertilizer recommendation.

Orientador: Ciro Antonio Rosolem / Banca: Leandro Borges Lemos / Banca: Carlos Alexandre Costa Crusciol / Banca: Silvestre Bellettini / Banca: José Antonio Quaggio / Resumo: Objetivou-se com este trabalho avaliar a dinâmica do potássio no sistema solo-palha-planta, com a rotação das culturas milheto, soja e aveia preta conduzidas em semeadura direta, em função do manejo da adubação potássica ao longo de três anos agrícolas. O experimento foi conduzido na Fazenda Experimental Lageado da FCA/UNESP, em Botucatu-SP, nos anos agrícolas de 2000/2001, 2001/2002 e 2002/2003. O solo foi classificado como Latossolo vermelho distroférrico de textura média (770 g kg-1 de areia, 210 g kg-1 de argila e 20 g kg-1 de silte). A área vinha sendo cultivada com soja em semeadura direta por um ano agrícola antes da instalação do experimento. No primeiro ano de condução do experimento, o milheto (Pennisetum glaucum, var. BN-2) foi semeado em Setembro/2000, sobre a palha de aveia preta (Avena strigosa). A adubação nesta semeadura foi de 20 kg ha-1 de P2O5 (Superfosfato Simples) e 15 kg ha-1 de N (Nitrocálcio). O milheto foi dessecado por ocasião da semeadura da soja (Glycine max L. Merrill, var. IAC-17), que foi semeada em Dezembro/2001, com 60 kg ha-1 de P2O5 . Em Abril/2001, fez-se a semeadura da aveia preta sem o uso de fertilizantes. A aveia preta foi dessecada na semeadura do milheto (Setembro/2001), que por sua vez foi dessecado na semeadura da soja (Dezembro/2001). As adubações do milheto e da soja foram as mesmas utilizadas no ano anterior. O delineamento experimental foi em blocos ao acaso, num esquema fatorial 4 x 4 ( 0, 30, 60 e 90 Kg ha-1 de K2O aplicados na semeadura do milheto x 0, 30, 60, 90 Kg ha-1 de K2O aplicados na semeadura da soja), constituindo 16 tratamentos, com quatro repetições. A palha da superfície do solo foi coletada na semeadura do milheto, na semeadura da soja, e aos 25, 50, 75 e 100 dias após a emergência da soja (DAE da soja), nos dois primeiros anos agrícolas. O solo foi coletado nas mesmas épocas de coleta... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this experiment was to study the potassium dynamics in no-tillage system, crop development and soybean yields, in different rates of potassic fertilization. The experiment was carried out in Fazenda Experimental Lageado in FCA/Unesp, in São Paulo state, Brazil, for 3 years. The soil was classified like Latossolo red distroférrico with medium texture (770 g kg-1 of sand, 210 g kg-1 of clay and 20 g kg-1 of silt ). The area had been cropped to soybean in no-tillage for one year before the experiment. In the first year, Pearl millet (Pennisetum glaucum, var. BN-2) was planted in September, over black oat (Avena strigosa) straw, receiving 20 kg ha-1 of P2O5 (Simple super phosphate) and 15 kg ha-1 of N (Calcium Nitrate). earl millet was desiccated at the same time that soybean (Glycine max L. Merrill, var. IAC-17) was planted, in December/2001, using 60 kg ha-1 of P2O5. In Abril/2001, black oat was planted without fertilizers. Black oat was desiccated at the same time that Pearl millet was planted (September/2001), and was desiccated at the next soybean planting (December/2001). Pearl millet and soybean fertilizations were the same as those used in the previous year. The experiment was carried out in a 4 x 4 factorial design with randomized complete blocks (0, 30, 60 and 90 Kg ha-1 of K2O applied at Pearl millet planting x 0, 30, 60, 90 Kgha-1 of K2O applied to soybean), with four replications. The soil surface straw was collected at Pearl millet planting and at soybean planting, at 25, 50, 75 and 100 days after soybean emergence (DAE), in both years. Soil samples were taken at the same times as straw samplings, in the layers 0-5, 5-10, 10-20, 20-40 and 40-60 cm deep, in both years. Soybean shoots were collected at 25, 50, 75 and 100 DAE, in both years. Roots were sampled at 50 DAE, in the same depths as soil was sampled. At harvest yields were determined... (Complete abstract click electronic access below) / Doutor

Made available in DSpace on 2014-06-11T19:22:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-05-04Bitstream added on 2014-06-13T20:28:25Z : No. of bitstreams: 1 zoca_sm_me_botfca.pdf: 788377 bytes, checksum: 4401184098c735dfc2400f9bbe8ce950 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O Brasil é o maior produtor mundial de café, com uma produção estimada em 43,5 milhões de sacas beneficiadas na safra 2011, uma vez que, o processamento do café gera grandes quantidades de resíduos sólidos, e também, esses resíduos podem proporcionar problemas ambientais, torna-se de grande importância o estudo de alternativas de utilização desses materiais, sendo assim, objetivou-se nesse experimento caracterizar cinco tipos de resíduos do benefício de café e avaliar seu valor como fertilizante potássico, estudando a liberação do nutriente. O experimento foi realizado em colunas com solo, em casa de vegetação, na Faculdade de Ciências Agronômicas Botucatu (SP). Foi utilizada a camada superficial (0-20 cm) de um Latossolo Vermelho distroférrico de textura média. Os materiais estudados foram cinco tipos de resíduos do benefício de café, sendo eles, a casca do café cereja despolpado, casca do café “boia” separado no lavador, casca do café “natural” seco em coco sem passagem pelo lavador, casca de café um ano compostada e casca de café enriquecida e compostada por três anos. Os resíduos foram aplicadas sobre o solo das colunas em quatro doses baseadas no teor total de potássio de cada material com testemunhas sem e com aplicação de fertilizante potássico mineral em quantidade equivalente à 300 kg ha-1 de K2O. O experimento foi conduzido pelo período de 10 meses. A água percolada foi coletada semanalmente e foram analisados pH, condutividade elétrica e K. Ao término do ensaio foram coletadas amostras de solo e analisados os teores de K nas diferentes profundidades do solo das colunas. Paralelamente ao ensaio foram confeccionados sacos de nylon para avaliar as alterações dos cinco tipos de resíduos do benefício de café utilizando o método do litterbag. Foram realizadas amostragens dos sacos... / Brazil is the world’s largest coffee producer. The estimated production in 2011 was 2.6 million tons of coffee beans, since the coffee processing generates large amounts of solid waste, and also, these residues can provide environmental problems, the study of coffee processing residues has great social, economic and environmental importance. The aim of the experiment was characterize five types of coffee processing residues and assess its value as a potassium fertilizer, studying the nutrient release. The experiment was carried out in columns with soil in a greenhouse at Agricultural Sciences College – UNESP - Botucatu – SP. The surface layer (0-20 cm) of a medium texture of an Oxisol was used. Five types of coffee processing residues were studied, which were the coffee cherry husk, the “float” coffee husk, the natural coffee husk, one year composted coffee husk and three years enriched and composted coffee husk. Four rates of residues were applied on the column’s considering the total potassium content and two controls with and without mineral potassium were used. The experiment was conducted for 10 months. The leached was collected every week and pH, K, and EC was analyzed. Soil samples were collected in the end of the period and K was analyzed in four layers. In parallel were made litterbags to assess the changes of the five types of coffee processing residues during the 10 months. The husks were sampled at 15, 45, 90, 150, 210 and 300 days. The samples were analyzed to total potassium, water soluble potassium, total... (Complete abstract click electronic access below)

In Mediterranean-type climates, topsoil frequently dries out during spring. Problems associated with reduced nutrient (P, K) availability in dry topsoil may be overcome by placing fertilisers deeper in the soil, where the soil is more likely to remain moist for longer periods as opposed to conventional fertiliser placement. Deep-P placement has resulted in significant yield improvements for lupin crops in Mediterranean environments because lupin crops generally require soil P supply during spring (throughout the flowering stage); in contrast, wheat yields have seldom improved with deep P placement, presumably because plants have accumulated sufficient P prior to spring (grain filling stage) for maximum grain yields. The P and K accumulation patterns of canola had not been investigated, and therefore any potential yield benefits of deep placed fertilisers were unknown. This study aimed to define the P and K demands of canola throughout the growing season, and assess the viability of deep placement of fertiliser in matching soil P and K supply to crop demand. The study further investigated the impact of deep placement of P fertiliser on root growth and distribution throughout the soil profile. Initial glasshouse studies compared the P and K accumulation patterns of several canola cultivars with wheat, and found that the P and K demand of canola continued until later into the season than wheat, but there was little difference in the P and K accumulation patterns of the various canola cultivars. Further experiments in sand culture determined that regardless of the level of K supply, canola plants had accumulated sufficient K for maximum seed yields by early flowering. Under high P supply, canola plants had accumulated enough P for maximum seed yields by early flowering, but when P supply during vegetative growth was just adequate, plants required a continual P supply until mid silique-filling to attain maximum yields. Because plants had accumulated sufficient K for maximum seed yields by early flowering (therefore topsoil drying in spring was unlikely to affect yields), further field experiments examined only deep placement of P fertiliser to improve P uptake and yields.

Resumo: O Brasil é o maior produtor mundial de café, com uma produção estimada em 43,5 milhões de sacas beneficiadas na safra 2011, uma vez que, o processamento do café gera grandes quantidades de resíduos sólidos, e também, esses resíduos podem proporcionar problemas ambientais, torna-se de grande importância o estudo de alternativas de utilização desses materiais, sendo assim, objetivou-se nesse experimento caracterizar cinco tipos de resíduos do benefício de café e avaliar seu valor como fertilizante potássico, estudando a liberação do nutriente. O experimento foi realizado em colunas com solo, em casa de vegetação, na Faculdade de Ciências Agronômicas Botucatu (SP). Foi utilizada a camada superficial (0-20 cm) de um Latossolo Vermelho distroférrico de textura média. Os materiais estudados foram cinco tipos de resíduos do benefício de café, sendo eles, a casca do café cereja despolpado, casca do café "boia" separado no lavador, casca do café "natural" seco em coco sem passagem pelo lavador, casca de café um ano compostada e casca de café enriquecida e compostada por três anos. Os resíduos foram aplicadas sobre o solo das colunas em quatro doses baseadas no teor total de potássio de cada material com testemunhas sem e com aplicação de fertilizante potássico mineral em quantidade equivalente à 300 kg ha-1 de K2O. O experimento foi conduzido pelo período de 10 meses. A água percolada foi coletada semanalmente e foram analisados pH, condutividade elétrica e K. Ao término do ensaio foram coletadas amostras de solo e analisados os teores de K nas diferentes profundidades do solo das colunas. Paralelamente ao ensaio foram confeccionados sacos de nylon para avaliar as alterações dos cinco tipos de resíduos do benefício de café utilizando o método do litterbag. Foram realizadas amostragens dos sacos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Brazil is the world's largest coffee producer. The estimated production in 2011 was 2.6 million tons of coffee beans, since the coffee processing generates large amounts of solid waste, and also, these residues can provide environmental problems, the study of coffee processing residues has great social, economic and environmental importance. The aim of the experiment was characterize five types of coffee processing residues and assess its value as a potassium fertilizer, studying the nutrient release. The experiment was carried out in columns with soil in a greenhouse at Agricultural Sciences College - UNESP - Botucatu - SP. The surface layer (0-20 cm) of a medium texture of an Oxisol was used. Five types of coffee processing residues were studied, which were the coffee cherry husk, the "float" coffee husk, the natural coffee husk, one year composted coffee husk and three years enriched and composted coffee husk. Four rates of residues were applied on the column's considering the total potassium content and two controls with and without mineral potassium were used. The experiment was conducted for 10 months. The leached was collected every week and pH, K, and EC was analyzed. Soil samples were collected in the end of the period and K was analyzed in four layers. In parallel were made litterbags to assess the changes of the five types of coffee processing residues during the 10 months. The husks were sampled at 15, 45, 90, 150, 210 and 300 days. The samples were analyzed to total potassium, water soluble potassium, total... (Complete abstract click electronic access below) / Orientador: Ciro Antonio Rosolem / Coorientador: Chad Penn / Banca: Roberto Lyra Villas Boas / Banca: José Antonio Quaggio / Mestre

Au Québec, la pomme de terre est cultivée sur des sols sableux favorisant les pertes par lixiviation de l’azote et du potassium. Selon le principe de réactions d’échanges cationiques, on a supposé que les doses et les sources d'azote puissent avoir un impact sur la lixiviation du potassium. Ainsi, une expérience a été menée, pendant trois années, dans un champ de pomme. Le dispositif expérimental est un bloc complet aléatoire de quatre répétitions constitué de 10 traitements qui sont un factoriel de trois sources d'azote (nitrate d’ammonium, sulfate d’ammonium et un engrais à libération lente) et trois doses (120, 200 et 280 kg N ha⁻¹) avec un traitement témoin. Des lysimètres ont été installés pour récupérer la solution du sol et doser sa concentration en potassium aux deux semaines. Les résultats ont révélé un effet non significatif de la source et de la dose de l'azote sur la lixiviation du potassium. Un modèle d’évolution de la lixiviation de potassium est obtenu pour aider les producteurs à mieux fractionner leurs engrais potassiques. Le bilan partiel de K montre une lixiviation nette pour les parcelles qui ont reçu une fertilisation azotée mais pas pour le témoin.

Baby spinach (Spinacia oleracea L.) is considered to be the one of the extremely nutritious vegetables, rich both in phytochemicals and core nutrients. Nowadays, phytochemicals in plants are raising interest in consumers for their roles in the maintenance of human health. Variation in content of bioactive compounds and core nutrients is the main concern in vegetable production. Factors such as cultural practices specially fertilization, may affect the nutritional and medicinal properties of the plants Therefore, three parallel trials for NPK to investigate the response of baby spinach leaves to nitrogen (N), phosphorus (P) and potassium (K) on chemical composition were conducted, with treatments arranged as follows: 0, 45, 75, 105, 120 kg·ha-1 N and P and 0, 60, 85, 106, 127, 148 kg·ha-1 K in a randomized complete block design (RCBD) with four replications. The results demonstrated that, application of nitrogenous, phosphorus, potassium fertilizers significantly increased the total phenolic content, total antioxidant activity, total flavonoid content and vitamin C while magnesium, iron, zinc and selenium did not exhibit significant response to all treatments applied. The increase in concentrations on total phenolic content, total antioxidant activity, total flavonoid content and vitamin C was observed, reaching maximum at 45 kg·ha-1 N, 75 kg·ha-1 P and 85 kg·ha-1 K. The optimum rates of 45 kg·ha-1 N, 75 kg·ha-1 P, 85 kg·ha−1 K were then used to formulate the NPK treatment combinations as follows: 0, 30: 30: 40, 45:45:60, 60:60:70, 75:75:90 kg·ha-1, arranged in a RCBD with three replicates. The results showed that total phenolic content, total antioxidant activity , total flavonoid content and vitamin C reached maximum in baby spinach leaves at N45:P45:K60 kg·ha-1 / Agriculture,  Animal Health & Human Ecology / M.Sc. (Agriculture)