O presente trabalho teve por objetivo estudar a resposta da cultura de melão conduzida em sistema orgânico a diferentes doses de substâncias húmicas extraídas de leonardita e esterco. Os tratamentos foram quatro doses de substâncias húmicas (0, 5, 10 e 20 mg.L-1 de solo) e esterco em combinação com dois biofertilizantes mais dois tratamentos adicionais utilizando fertilizantes convencionais com e sem esterco. O delineamento experimental foi em blocos ao acaso, com doze tratamentos e três repetições. Em função dos resultados obtidos, nas condições do experimento (solo com baixa CTC e baixo teor de matéria orgânica), pode-se concluir que: (i) a melhor resposta da cultura de melão (produtividade total e comercial, número de frutos comerciais e comprimento do fruto), conduzido em sistema orgânico de produção, na região de Petrolina-PE, é obtida com a adição de esterco; (ii) a produtividade total e comercial, o número total e comercial de frutos e a massa média de frutos de melão aumentaram com as doses de substâncias húmicas combinadas ao biofertilizante Agrobom; e (iii) não houve efeito da adição de esterco e das doses de substâncias húmicas, em combinação com caldas biofertilizantes aplicadas via fertirrigação na firmeza, na espessura da casca e no diâmetro da cavidade do fruto. / The present experiment had the aim of studying organic melon crop response to different rates of humic substances extracted from leonardite and manure. The treatments were four rates of humic substances (0, 5, 10 and 20 mg.L-1) and manure combined with two biofertilizers and two additional treatments using conventional fertilizers with and without manure. The experimental design was randomized complete blocks, with twelve treatments and three replications. The results (under similar soil conditions: low CEC and low organic matter content) allowed the following conclusions: (i) for all tested organic production systems, carried out at Petrolina, Pernambuco State (Brazil), the higher total and commercial yield, and the number and length of commercial melon fruits were obtained with manure addition; (ii) the higher rates of humic substances, combined with Agrobom biofertilizers, increased the total and commercial yield, the total and the commercial number and the mean mass of melon fruits; and (iii) there was no effect of manure addition and humic substances application (combined with two biofertilizers applied by fertigation) on the hardness, rind thickness and socket diameter of melon fruit.

A vinhaça é um resíduo da produção de etanol e reutilizada nas áreas de cana-de-açúcar fornecendo nutrientes para cultura, principalmente potássio. Gerada na proporção de 10 a 13 litros para cada litro de etanol produzido, a vinhaça representa uma excelente alternativa aos fertilizantes químicos e apresenta desafios ambientais e técnicos para sua aplicação nos solos agrícolas. O manejo inadequado da aplicação de vinhaça pode acarretar, além dos problemas ambientais, pior qualidade da matéria prima para indústria. Esta pesquisa teve como objetivo estudar o efeito da aplicação de diferentes doses de vinhaça via gotejamento subsuperficial no desenvolvimento, na produtividade agrícola, nos parâmetros tecnológicos (oBrix, Pol, pureza, fibra, açúcar redutor, açúcar redutor toral, açúcar total recuperável e teor de cinzas), na produção de bioprodutos da cana-de-açúcar e nas alterações do pH e da condutividade elétrica da solução do solo, além da avaliação do sistema de irrigação por gotejamento subsuperficial. O experimento foi instalado na área experimental do Departamento de Engenharia de Biossistemas - USP/ESALQ, situada em Piracicaba-SP. Foi adotado o delineamento estatístico inteiramente casualizado com 6 tratamentos e 4 repetições, sendo o tratamento 1 sem irrigação e com adubação convencional junto ao plantio, tratamento 2 fertirrigado convencional, e os tratamentos de 3 a 6 fertirrigados com diferentes doses de vinhaça. O tratamento 4 recebeu a dose (DCETESB) calculada segundo os critérios da norma técnica P4.231/2005 da CETESB, e os tratamentos 3, 5 e 6 receberam, ½ DCETESB, 2xDCETESB e 3xDCETESB, respectivamente. Dois ciclos, cana-planta e primeira soca, foram avaliados. O acompanhamento do pH e da condutividade hidráulica do solo, o desenvolvimento vegetativo, a análise nutricional das folhas e o desempenho do sistema de irrigação foram avaliados no primeiro ciclo. A produção de biomassa, a produção de açúcar, a produção de etanol foram avaliados nos dois ciclos. Os resultados mostraram que houve um aumento dos valores de pH e CE no solo, diante do aumento do volume aplicado, mas evidenciou-se a necessidade de um maior intervalo de tempo para a percepção de suas diferenças. Os tratamentos 4, 5 e 6 apresentaram maiores valores de área foliar e altura de planta em relação ao tratamento 1, enquanto que os outros dados de biometria não apresentaram diferença entre os tratamentos. As análises foliares realizadas mostraram que não houve influência das doses de vinhaça no estado nutricional das plantas. Dentre os parâmetros tecnológicos avaliados o teor de cinzas no caldo foi influenciado pela aplicação de diferentes doses nas duas colheitas realizadas, já os outros parâmetros não foram influenciados. A produtividade de cana-de-açúcar apresentou diferença entre os tratamentos apenas na primeira colheita, sendo que aplicação de vinhaça resultou no aumento de produção. Esse aumento de produtividade ocorrido no primeiro ciclo resultou diretamente em um aumento do etanol de segunda geração (E2G), enquanto que a produção de açúcar, etanol de primeira geração (E1G) e etanol total (E1G+E2G) não apresentaram diferença significativa entre os tratamentos. / Vinasse is a by-product from ethanol production and reused in sugarcane fields providing nutrients to the plants, mainly potassium. Generated at a rate of 10-13 liters for every liter of ethanol, the vinasse represents an excellent alternative to chemical fertilizers and it also presents environmental and technical challenges for its applications on agricultural soils. Mismanagement of vinasse can cause environmental impacts and lower the quality of sugarcane production. This study had as aim to study the effect of application of different doses of vinasse by a subsurface drip irrigation system in sugarcane vegetative development, sugarcane yields, technological parameters, bio-products production, changes in pH and electrical conductivity (EC) of the soil, evaluation of potential to use of drip irrigation to apply vinasse. A completely randomized design with 6 treatments and 4 repetitions was conducted at experimental area of Bio systems Engineering Department of USP/ESALQ, placed in Piracicaba-SP. The treatment 1 was performed in dry land system with chemical fertilization at planting; treatment 2 was fertigated with chemical fertilizers (no vinasse); treatments from 3 to 6 received different levels of vinasse. Treatment 4 received the dose (DCETESB) calculated in according to criteria from technical standard P4.231/2005 of CETESB, and treatments 3, 5 and 6 received ½ DCETESB, 2xDCETESB and 3xDCETESB, respectively. Two cycles of sugarcane were evaluated, first year and firs ratoon. The monitoring of pH and EC of the soil, vegetative development, leaf nutrional analysis and drip irrigation performance were evaluated at first cycle. Biomass, sugar and ethanol production were evaluated at first and second cycles. The results showed that an increase of pH and EC occurred due to the vinasse application, however, was evident the need of a higher interval of time to see the differences. Treatments 4, 5 and 6 showed higher values of leaf area and plant height when compared to treatment 1, while the another biometric data did not show difference between the treatments. Leaf nutritional analysis showed that did not have effect of vinasse doses in nutritional status of the plants. Among technological parameters just as content was affected by the application of different doses of vinasse at two harvests, and the another parameters were not affected. Sugarcane yields showed difference between treatments just at first year when vinasse application resulted in production increasing. This increase caused an increase of second generation ethanol production (E2G), while the sugar, first generation ethanol (E1G) and total ethanol (E1G+E2G) did not show significance difference between treatments.

A concentração de sais na água é um dos principais aspectos a ser observado para se definir uma estratégia de manejo da irrigação, podendo levar a prejuízos pela salinização do solo, com conseqüente redução do rendimento das culturas. Visto que culturas tolerantes à salinidade apresentam maiores teores foliares de certos nutrientes, então a adubação em culturas sensíveis poderia ser conduzida de modo a elevar os teores destes nutrientes nas folhas, promovendo aumento da tolerância da cultura aos sais. Este trabalho teve o objetivo de estudar os efeitos de três doses de N e K na tolerância da cultura do tomateiro à salinidade, bem como avaliar a performance de medidores de íons específicos (MIE) na determinação de nutrientes na solução do solo e na seiva da planta. Mudas de tomateiro, híbrido Facundo, foram transplantadas em 23/10/2001 em vasos contendo 60 kg de solo franco-argilo-arenoso, no espaçamento de 1,0 x 0,5 m, em um ambiente protegido com cobertura de polietileno. Os tratamentos foram compostos pela combinação de três níveis de N (7,5; 15,0 e 22,5 g planta-1) e três níveis de K (8, 16 e 24 gK2O planta-1) aplicados via fertirrigação por gotejamento, no esquema fatorial 3x3 com cinco repetições, sendo que à água de irrigação foram adicionados os sais cloreto de sódio e cloreto de cálcio para obtenção de condutividade elétrica da água de 9,5 dS m-1. Foram realizadas coletas da solução do solo e da seiva do pecíolo para determinações dos nutrientes pelos MIE, cujos valores foram comparados com as determinações pelos métodos-padrões. Não foram observados efeitos significativos dos tratamentos sobre o desenvolvimento e a produtividade das plantas, bem como sobre a qualidade dos frutos. As concentrações de nutrientes na solução do solo determinadas com os MIE apresentaram boa correlação com as determinações pelos métodos-padrões, e as concentrações de nutrientes na seiva do pecíolo foram bem correlacionadas aos teores na matéria seca das folhas. A condutividade elétrica e a concentração iônica na solução do solo não puderam ser estimadas a partir dos valores medidos no extrato de saturação ou na solução 1:2 apenas pela correção de umidade, com exceção do K e Na, cujas estimativas foram satisfatórias para baixas concentrações destes elementos na solução do solo. / The concentration of salts in the water is one of the main aspects to be observed to define a strategy of irrigation management, which could take to damages due to the soil salinization, with consequent reduction of crops yield. Once tolerant crops to salinity present larger tenors of some nutrients in the leaves, then the fertilizing in sensitive crops could be conducted in order to increase the tenors of these nutrients in the leaves to increase the crop tolerance to salts. This work had the objective of studying the effects of three doses of N and K in the tomato tolerance to salinity, as well as to evaluate the performance of cardy-ion meters (CIM) in the determination of nutrients in the soil solution and in the sap of the plant. Tomato seedlings, hybrid Facundo, were transplanted in 10/23/2001 in vases containing 60 kg of a sandy-clay-loam soil, spaced 1.0 x 0.5 m, in a greenhouse covered with polyethylene film. The treatments were composed by the combination of three levels of N (7.5; 15.0 and 22.5 g plant-1) and three levels of K (8, 16 and 24 gK2O plant-1) applied by drip fertigation, in the 3x3 factorial scheme with five replications. Salts (sodium chloride and calcium chloride) were added to the irrigation water for obtaining an electric conductivity of 9.5 dS m-1. Soil solution and petiole sap were collected for determinations of the nutrients with the CIM, whose values were compared with the determinations by the standard methods. Significant effects of the treatments were not observed for the development and yield of the plants, as well as for the fruits quality. The concentrations of nutrients in the soil solution determined with CIM showed good correlations with the determinations by the standard methods, and the concentrations of nutrients in the petiole sap were well correlated to the tenors in the dry matter of the leaves. The electric conductivity and the ionic concentration in the soil solution could not be estimated from the measured values in the saturation extract or in the solution 1:2 only by the correction of the water content, except for K and Na, whose estimates were satisfactory for low concentrations of these elements in the soil solution.

Orientador: Edson Eiji Matsura / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-20T08:31:34Z (GMT). No. of bitstreams: 1 Elaiuy_MarceloLeiteConde_M.pdf: 2524526 bytes, checksum: 84d50a1f8818194cd8b6d4600d61a6be (MD5) Previous issue date: 2012 / Resumo: O uso de efluente de esgoto tratado (EET) na agricultura combinado com o método de irrigação por gotejamento subsuperfical (IGS) pode reduzir os custos de produção agrícola, fertirrigando de maneira eficiente as culturas. O conhecimento da dinâmica da água e do soluto no solo ao redor do gotejador contribui para o dimensionamento da IGS. Neste estudo, comparou-se as dimensões do bulbo úmido formado pela aplicação de EET e água de abastecimento municipal (AAM) em um Latossolo Vermelho distroférrico, para verificar o efeito da qualidade da água e da vazão entre gotejadores utilizados na cultura da cana-de-açúcar. O experimento de campo foi conduzido na Faculdade de Engenharia Agrícola da Unicamp aonde foram instaladas sondas de TDR, utilizadas para estimar a distribuição do conteúdo de água no solo e a condutividade elétrica (CE). Três trincheiras foram abertas e as sondas foram dispostas a 0,15; 0,25; 0,35; 0,45; 0,55 e 0,65 m de profundidade, e a 0,05; 0,15; 0,25 e 0,35 m de distância do gotejador, totalizando 21 sondas em malha por trincheira. Em duas paredes opostas de cada trincheira utilizou-se um gotejador enterrado a 0,30 m para cada uma das vazões constantes, 1,0 L h-1 e 1,6 L h-1. O volume molhado no solo foi observado ao longo do tempo em cada aplicação de 1,0 L de AAM, totalizando 10 aplicações. Após um período de 15 dias foi adotada a mesma metodologia de aplicação, e observado o volume molhado no solo com EET. Os resultados dos diferentes perfis de umidade do solo mostraram que as dimensões vertical e horizontal do bulbo úmido são similares para a AAM e para o EET, sendo peculiares de acordo com as vazões utilizadas e volume aplicado. Observou-se também para o EET uma maior concentração de soluto próximo ao gotejador decaindo progressivamente com a frente de molhamento / Abstract: The use of treated sewage effluent (TSE) in agricultural combined with the subsurface drip irrigation (SDI) method may decrease the costs in agricultural production, in attempts to fertigate crops more efficiently. The precise knowledge about the dynamic of water and solute in the soil around the emitters contribute for a proper design of SDI. In this study, we compared the dimensions of the wet bulb formed by the application of TSE and municipal water supply (MWS) in a dusk red latosol, to evaluate the effect of water quality and discharge between drippers, used in sugar cane crop. The field experiment was conducted at the College of Agricultural and Engineering/State University of Campinas, where TDR probes were used to monitor the distribution of soil water content and electrical conductivity (EC). Three trenches were opened and 21 three-rod TDR probes were installed, placed at 0.15, 0.25, 0.35, 0.45, 0.55 and 0.65 m - in depth, and 0.05, 0.15, 0.25 and 0.35 m - distance from the dripper, totaling 21 probes in mesh per trench. In two opposite walls of each trench this procedure was replicated using a dripper buried at 0.30 m for each constant discharge of 1.0 L h-1 and 1.6 L h-1. The wetted soil volume was observed over time in each application with 1 L of MWS, totaling 10 applications. After a period of 15 days, was adopted the same methodology of application and the wetted soil volume was observed with TSE. The results from different wetted soil profiles indicated that dimensions vertical and horizontal of the wet bulb are similar for the MWS and TSE, being peculiars according to the discharges used and volume applied. We also observed for the TSE greater solute concentration near the emitter decreasing progressively towards the wetting front / Mestrado / Agua e Solo / Mestre em Engenharia Agrícola

The goal of this work was to determine the N requirements of the muskmelon crop and adjusting a method for diagnosis of the plant nutritional status, for estimations of fertilization rates to be used during growth and development of this crop. The experiment was carried out at Departamento de Fitotecnia - UFSM, inside a 500m2 screenhouse. Muskmelon plantlets, hybrid Magelan, were planted at September 30th, 2004, in 4.5dm3 plastic bags containing a commercial substrate. Plant density was 3.3 plants m-2. Water and nutrients were supplied by fertigation. Treatments were five nutrient solutions with N concentrations (NO3 - /NH4 + ) of 8 (T1), 11 (T2), 14 (T3), 17 (T4) and 20mmol.L-1 (T5). The other nutrients were supplied at standard concentrations of 0.9 H2PO4 - ; 2.25 SO4 -- ; 10.0 Ca++; 6.0 K+ and 5.0mmol.L-1 Mg++, with micronutrients. Four plants were weekly harvested from 33 to 99 days after planting (DAP) to determine dry mass (DM), number of fruits (NF), leaf area index (LAI) and N content in tissues. Ripe fruits were harvested at the peduncle abscission stage and fresh weight, flesh firmness, fraction of flesh, skin, mucilage and seeds, titratable acidity and soluble solids were determined. The N content in leaf, stem, petiole and fruit tissues was determined by the Kjeldahl method. The vegetative and total dry mass, leaf area, number and fruit yield increased linearly by effect of treatments. For fruit quality variables, only the titratable acidity decreased by increasing N concentrations. The N dilution was observed during growth of tissues upon all treatments and data fitted the potential model %N = aMS-b described in the literature. The N critical dilution curve was adjusted, with values of 5.16 and 0.63 for model coefficients a and b, respectively. It was concluded that N affects the yield of the crop and can be supplied at rates estimated from the critical dilution curve until fruit setting was attained. After this stage, N fertilization rates can be adjusted in order to avoid any restrictions in the leaf area growth. / Os objetivos deste trabalho foram determinar as necessidades de N pela cultura do melão e ajustar um método de diagnóstico das doses de adubação no decorrer do ciclo de crescimento e desenvolvimento. O experimento foi conduzido no Departamento de Fitotecnia da UFSM, no interior de um abrigo de 500m2, coberto com polietileno aditivado de 150μm de espessura. Mudas de melão do híbrido Magelan foram plantadas em 30/09/2004 em sacolas de polietileno com 4,5dm3 de substrato comercial, na densidade de 3,3 plantas.m-2 as quais foram fertirrigadas com solução nutritiva completa. Os tratamentos consistiram por cinco concentrações de nitrogênio (NO3 -/NH4) de 8 (T1), 11 (T2), 14 (T3), 17 (T4) e 20mmol. L-1 (T5). Os demais nutrientes foram fornecidos nas mesmas concentrações para os cinco tratamentos, sendo de 0,9 de H2PO4 - ; 2,25 de SO4 -- ; 10,0 de Ca++; 6,0 de K+ e 5,0mmol L-1de Mg++, complementadas por micronutrientes. Para determinação da massa seca (MS), número de frutos (NF), índice de área foliar (IAF) e o teor de Nitrogênio nas folhas, haste, pecíolos e frutos, foram coletadas semanalmente quatro plantas de cada tratamento no período entre 33 e 99 dias após o plantio (DAP). A massa seca de cada órgão foi moída em moinho tipo Willey e a concentração de N determinada pelo método Kjeldah. A colheita foi feita diariamente quando os frutos evidenciaram a zona de abscisão completa em torno do pedúnculo. As características avaliadas foram o peso de fruto, firmeza da polpa, as frações da polpa, casca, mucilagem e sementes, acidez titulável (AT) e o teor de sólidos solúveis totais (TSS). Os resultados foram submetidos à análise da variância e os dados das variáveis que apresentaram diferenças significativas entre os tratamentos foram submetidos à análise de regressão. Foi observada resposta linear dos tratamentos na massa seca vegetativa e total, área foliar, número de frutos e produtividade. Quanto às características qualitativas dos frutos, somente a acidez titulável apresentou diferença significativa, decrescendo com o aumento da concentração de N. Foi observada a diluição da concentração de N na massa seca em todos os tratamentos e os dados ajustaram-se ao modelo potencial %N = aMS-b descrito na literatura. A curva crítica de diluição do N foi ajustada, com coeficientes a e b iguais a 5,16 e 0,63, respectivamente. Concluiu-se que o N interfere na produtividade e deve ser fornecido em doses não superiores à curva crítica de diluição até a que a fixação dos frutos tenha sido atingida. Após essa fase doses devem ser ajustadas de forma a evitar restrições no crescimento da área foliar e dos frutos.

Fever tea is one of the important medicinal plants belonging to the family Verbenaceae. The leaves of the plant are used as a remedy to treat malaria, stomach pains, colds and fever. There are different clones of Lippia species available with different medicinal value. Therefore, the purpose of this study was to determine protocols for propagation of fever tea so as to multiply an ideal clone. Vegetative propagation of this plant species by stem cuttings, requirements for seed germination and response of fertigation frequencies and growing medium to growth, yield and quality has not been studied. In this study, factors influencing effective propagation of fever tea were studied. Those factors were: cutting position (apical vs. basal), media (pine bark vs. sand), hormone (seradix No. 2 vs. no hormone) light and temperature requirement for fever tea seed germination and effect of fertigation frequencies (0.4 L/day, 1L/day, 2L/day, 2L/2nd day and 2L/week) and growing media (pine bark vs. sand) on growth, oil yield and oil quality. In vegetative propagation by stem cuttings, measurements made were number of roots per rooted cutting, fresh mass, stem circumference and number of leaves and the rate of rooting during four consecutive sampling dates (5, 10, 15 and 20 days after planting). Apical cuttings rooted earlier by 5 days than basal cuttings at 10 days but at 15-20 days after establishment, both cuttings had good rooting. Fresh mass was not affected by cutting position and rooting media, but cuttings performed slightly better when propagated in pine bark medium than sand medium. Basal cuttings resulted in thicker stems and more leaves as compared to apical cuttings. Seradix No.2 (0.3% IBA) hormone increased the fresh mass, stem circumferences, root number and leaf numbers on both apical and basal cuttings. For the establishment of fever tea stem cuttings, both apical and basal cuttings can be used but pine bark is the ideal medium. The cuttings can be ready for transplanting in 15-20 days after establishment and Seradix No. 2 (0.3% IBA) promotes rooting of fever tea cuttings. The ideal combination of light and temperature for seed germination of fever tea was investigated. Germination was tested at constant temperature regimes (15, 20, 25 and 30¨¬C with continuous light or dark period and alternating temperatures of 20:30 and 16L: 8D (light: dark) combinations respectively. Seeds started to germinate after 8 days from incubation and the last germination was observed at 30 days from incubation. Germination percentages increased at 20-30 constant temperatures and 20/30 alternating temperatures but the difference amongst them was not significant. Higher germination of 86% were achieved when seeds were exposed to continuous light than alternating light and dark. Seeds failed to germinate in continuous darkness. Fever tea seeds were positively photoblastic. The effect of fertigation frequency and growing medium on the growth, yield and quality of fever tea were investigated in a tunnel. Treatments used were five fertigation frequencies (0.5L/day, 1L/day, 2L/day, 2L/2nd day, and 2L/week) and two growing media (pine bark and sand). Measurements made were plant height, stem circumference and number of branches at 8, 16 and 32 weeks after planting. At 8 weeks after planting all fertigation frequencies improved fever tea growth except fertigation frequency of 2L/week. All the fertigation frequencies were ideal to sustain the growth and development of fever tea plants except 2L/week. At 16 weeks after planting there were interactive effects between fertigation frequencies and the growing medium for the plant height of fever tea. Plants fertigated with 2L/day grown in sand media grew taller than all the other fertigation frequencies. At 32 weeks after planting there was a significant effect on the plant height from the main effects of fertigation frequency and growing medium. Plants fertigated with 2L/day were significantly the tallest followed by plants fertigated with 0.5L/day, 1L/day, 2L/2nd day and 2L/week. When plants were younger better plant growth was obtained in pine bark media. Stem circumference and number of branches of fever tea were significantly affected by fertigation frequency and growth medium. At 16 and 32 weeks after planting, plants grown in sand media had thicker stems and more branches as compared to plants grown in pine bark media. The essential oil of fever tea was extracted using hydro-distillation. Fertigation frequency did not affect oil yield. Plants grown in pine bark media yielded more oil than plants grown in sand medium. Microscopical studies using scanning electron microscope were investigated to determine the development of oil glands and trichomes on the abaxial (upper) and adaxial (lower) surfaces of the leaves as affected by fertigation frequency and the growing medium. There were no significant effects on the number of oil glands and trichomes developed on both surfaces of the leaves. Pine bark medium resulted in larger oil glands than sand medium regardless of the treatments, and pine bark also yielded more oil percentages than sand medium. Based on this investigations for commercial production of fever tea essential oil pine bark media is recommended. Chemical compounds of fever tea oil were also not affected by fertigation frequency or growth medium. In this study the chemical compounds detected from essential oils of fever tea were monoterpenes (i.e. ¥á-pinene, sebinen, 1.8 cinede, myrcene, ipsenone and ipsedienone) and the sesquiterpenes (i.e. ¥â-caryophyllene and germacrene-D). Compounds that gave the smallest chemical percentages and the shortest time to be detected were ¥á-pinene, sebinen, 1.8 cinede, myrcene, ipsenone and ipsedienone. Compounds found with the highest chemical percentages with highest peaks were ¥â-caryophyllene and germacrene-D. / Dissertation (MSc (Horticulture))--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted

Orientador: Roberto Lyra Villas Bôas / Coorientador: Thais Regina de Souza / Banca: João Carlos Cury Saad / Banca: Rafael Damatto Júnior / Resumo: A citricultura é um segmento de grande importância para o Brasil, que é o maior produtor mundial de laranja. A fertirrigação é uma prática que está cada vez mais se expandindo no cenário da citricultura, sendo esta técnica geralmente realizada através de doses preestabelecidas, sem qualquer monitoramento do estado nutricional da planta e do solo. O manejo inadequado da fertirrigação pode ocasionar certos desequilíbrios nas condições de solo e no estado nutricional da planta ao longo do tempo. As técnicas tradicionais de monitoramento da condição do solo e da planta não permitem o fornecimento de dados com rapidez, para que possa ser realizada uma alteração na adubação, desperdiçando assim este grande potencial da fertirrigação. O objetivo deste trabalho foi de avaliar o efeito de cinco doses de N e K sobre a produção e estado nutricional de plantas cítricas, correlacionando os resultados de análise da seiva, análise do teor de clorofila e solução do solo com os resultados da análise do solo e foliar, assim observando a sensibilidade destes métodos com relação à variação das doses destes nutrientes. Para isso foi conduzido um experimento em campo, na cidade de Reginópolis-SP/Brasil, utilizando-se laranjeiras da variedade 'Hamlin', sobre portaenxerto citrumelo Swingle. Os tratamentos consistiram de cinco doses de N e K, aplicadas via fertirrigação: T1 - controle (sem nutriente); T2 - 25%; T3 - 50%; T4 - 100% e T5 - 200% da dose de N e K. A dose 100%, oficialmente recomendada, foi definida com base no histórico de análises de solo e folhas e também em função da produtividade esperada. A partir desta dose foram calculadas as outras. Para monitorar o estado nutricional das plantas foram realizadas análises de folha e seiva e também foi determinada a medida indireta da clorofila. A dinâmica... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The citrus industry is a segment of great importance to Brazil, which is the world largest producer of orange. Fertigation is a technique that is increasingly expanding in the citriculture, but this technique is usually performed using predetermined doses without monitoring the nutritional status of plant and soil. The mismanagement of fertigation can cause imbalances in soil conditions and plant nutritional status over time. Traditional techniques for monitoring the condition of the soil and the plant does not allow the provision of data quickly, wasting this great potential of fertigation. This research aimed to evaluate the effect of five N and K rates on the yield and nutritional status of citrus plants, correlating the results of sap analysis, indirect measurement of the chlorophyll and soil solution analysis with the results of the leaf and soil analysis, thereby observing the sensitivity of these methods. The experiment occurred out in the city of Reginópolis-SP/Brasil, using 'Hamlin' trees, grafted on citrumelo Swingle rootstock. The treatments consisted of five N and K rates, applied through fertigation: T1 - control (no nutrient), T2 - 25%, T3 - 50%, T4 - T5 and 100% - 200% of N and K. The 100% rate, officially recommended, was established based on historical of soil and leaf analysis and also in accordance with the expected productivity. The remaining rates was calculated from it. To monitor the nutritional status of the plants, leaf analysis, sap analysis and the indirect measurement of the chlorophyll were employed. The nutrients dynamics in the soil was evaluated by soil sampling and by the soil solution analysis, with the help of porous covering soil solution extractors. The yield was also quantified. In the soil solution was observed decrease in pH and increase in electrical conductivity and in ammonium, nitrate, potassium... (Complete abstract click electronic access below) / Mestre

Bush tea (Athrixia phylicoides) is a medicinal herbal tea, which is used for cleansing or purifying the blood, treating boils, bad acne as well as infected wounds and cuts. A. phylicoides also has the potential to be used as an ornamental cut flower due to its beautiful flowers. Because of the many uses of bush tea, it faces problems of being over harvested and exploited. Therefore, there is a need to study more about the plant for possible domestication. A questionnaire survey was conducted in selected villages of Thohoyandou and Nzhelele in Venda, Limpopo Province, by means of personal interviews. The aim of the survey was to gather indigenous knowledge and validate the uses of bush tea from the local people. Interviews were conducted on three types of respondents, viz. traditional healers (31%), street sellers (25%) and bearers of indigenous knowledge (44%). A total of one hundred respondents were interviewed. One important finding of the study was that people from the area of study possess a remarkable knowledge of the plant and its uses to treat a wide range of physical ailments. The bush tea plant is used as medicine, health tea as well as a traditional broom. Some of these ailments that could be treated using bush tea were headaches, stomachache, influenza and leg wounds. It is known to have aphrodisiac properties and it can also be used to cleanse the womb, kidney, and veins and to purify blood. The plant was harvested in different ways depending on the reason for harvesting. Results from the survey indicated that the majority of the respondents had no interest in propagating the bush tea plant, few respondents showed interest in propagating the plant. They also showed enhanced knowledge about the uses of other medicinal plants. A tunnel experiment was also conducted at the Hatfield Experimental Farm of the University of Pretoria in South Africa. The effects of growing media (pine bark and sand) and fertigation frequencies (0.4 ℓ/day, 1 ℓ/day, 2 ℓ/day, 2 ℓ/2nd day and 2 ℓ/ week) on growth and yield of bush tea were studied. Growing media and fertigation frequencies significantly affected the growth performance and yield of bush tea. The growth rate of bush tea between the autumn season and winter season was higher than between winter and spring season. Greater number of stems and shoots were observed in sand grown plants as compared to pine bark grown plants. Sand grown plants had a higher root mass as compared to those of pine bark grown plants over both seasons, with nonsignificant differences in the dry root mass in winter (90 days after planting). Plants grown in sand had significantly longer roots (P≤ 0,05) than plants grown in pine bark at 90 days after planting. However, at 180 days after planting the differences in root lengths were no longer significant. Fertigation frequencies caused significant differences in growth performance and yield of bush tea. Plants fertigated with 1 ℓ/day were significantly the tallest, followed by plants fertigated with 0.4 ℓ/day, 2 ℓ/day, 2 ℓ/2nd day and 2 ℓ/ week. Our results confirmed that bush tea could grow up to 1 metre high (1.08 m). In addition, fertigation frequency of 1 ℓ/day resulted in plants with greater stem and leaf mass (both fresh and dry), thus higher yields. Fertigation frequency of 2 ℓ/day was found to be too high and hence reduced oxygen supply to the roots and consequently retarded above plant growth. Sand grown plants also produced more flowers than pine bark grown plants. Overall, plants grown in sand media had superior stem and shoot mass, leaf mass, root mass and flower mass compared to plants grown in pine bark. Plants that received insufficient amount of water (2 ℓ /week) resulted in stunted growth and produced the least yield. In conclusion, bush tea plants performed better in sand growth media than in pine bark growth media. An optimum application rate of 1 ℓ/day was ideal for growth and performance of bush tea as the plant performed better under this fertigation frequency. / Dissertation (MInstAgrar)--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted

As plantas tropicais vêm ocupando uma parcela crescente do setor de floricultura, tanto no mercado nacional quanto no internacional, por apresentarem formas exuberantes e coloridas. Neste sentido, o Costus lasius Loes. tem se destacado entre as plantas ornamentais por possuir, como característica mais atraente, pequenas inflorescências amarelo-ouro e caule pouco espiralado, marcas que dão leveza à combinação de plantas de vaso. Entretanto, esta espécie é pouco pesquisada no Brasil, principalmente quanto às condições ambientais de cultivo, de nutrição e de manejo da fertirrigação. O presente trabalho tem como objetivo avaliar o efeito de diferentes malhas fotoconversoras de sombreamento e diferentes concentrações de potássio, no cultivo de Costus lasius em ambiente protegido. O experimento foi conduzido em uma área experimental do Departamento de Produção Vegetal da Escola Superior de Agricultura \"Luiz de Queiroz\", em Piracicaba, SP. Os tratamentos foram constituídos da combinação de cinco concentrações de potássio na solução de fertirrigação (40, 80, 120, 160 e 200 mg L-1), com três diferentes colorações de cobertura Chromatinet (Polysak Plastic Industries Ltd), nas cores vermelha, azul e preta, com índice de sombreamento de 50%. Foram utilizados 25 vasos \"pote 19\" por malha, em um total de 75, com um número de duas plantas por vaso, dispostos em bancadas de alumínio já disponíveis no local. Foram avaliados o crescimento das plantas, o número de folhas, de hastes e de inflorescências, as dimensões das hastes e das inflorescências, a sanidade das folhas e das inflorescências, o índice de preenchimento de vaso, a matéria fresca e seca, o índice de área foliar, o índice de estresse hídrico da cultura, o índice de clorofila e o acúmulo das concentrações de macronutrientes no tecido vegetal. O sombreamento com a malha vermelha melhorou as características de crescimento, número de folhas e aumentou a produção de massa fresca e seca de costus. A concentração de 200 mg L-1 de K+, na solução de fertirrigação, é a recomendada para aumentar a massa fresca e o maior número das inflorescências, características relevantes para a espécie Costus lasius como planta ornamental. Os maiores teores de potássio acumulados nas inflorescências do costus são proporcionados pela concentração 200 mg L-1 sobre as malhas vermelha e azul; e pela concentração 160 mg L-1 no ambiente sombreado com a malha preta. A dose de 200 mg L-1 de K+ associada a malha preta conduzem aos melhores resultados em termos de produção de hastes e inflorescências. O cultivo de costus sobre a malha azul tem maior eficiência no aproveitamento da clorofila e no processo fotossintético, indicando a camada basal das folhas como referência para esse tipo de avaliação. O IEHC apresenta grande variabilidade durante todo o ciclo e indica o ambiente de malha vermelha como o mais passível de causar estresse hídrico para as plantas na maioria dos meses estudados. / Tropical plants have been participating of a growing portion in brazilian floriculture and in international markets, because of its exuberant and colorful forms. In this sense, the Costus lasius Loes. has stood out among ornamental plants because of its more attractive characteristics: small yellow-gold inflorescences and slightly spiraled stem, attributes that give lightness to the potted plants. However, there are few studies about this species in Brazil and mainly regarding the environmental conditions of cultivation, nutrition and fertirrigation management. The goal of this work is to evaluate the effect of different photoconverters meshes and different concentrations of potassium in the cultivation of Costus lasius in greenhouse. The experiment was conducted in an experimental area of the Plant Production Department at the School of Agriculture \"Luiz de Queiroz\", in Piracicaba, SP. Treatments were composed by a combination of five potassium concentrations in the fertigation solution (40, 80, 120, 160 and 200 mg L-1) in three different meshes (Polysak Plastic Industries Ltd): red, blue and black, with shading capacity of 50%. For each meshe color twenty-five pots were used, 75 pots in total, with two plants per pot, arranged in aluminum benches already available at the place. In this experiment were evaluated the plants growth, number of leaves, stems and inflorescences, dimensions of stems and inflorescences, leaves and inflorescences health, vessel filling index, fresh and dry matter, leaf area index, crop water stress index, chlorophyll index and accumulation of macronutrients concentrations in plant tissue. The shading with the red mesh improved the growth characteristics, number of leaves and increased the production of fresh and dry mass of costus. The K+ concentration of 200 mg L-1 in the fertigation solution is recommended to increase the fresh mass and to achieve the highest number of inflorescences, which are relevant characteristics for the specie Costus lasius as ornamental plant. The highest levels of accumulated potassium in costus inflorescences are provided by the concentration of 200 mg L-1 on the red and blue meshes; and by the concentration of 160 mg L-1 in the environment shaded with the black mesh. The dose of 200 mg L-1 of K+ associated with black mesh leads to the best results in terms of stem and inflorescence production. The cultivation of costus on the blue mesh has greater efficiency in the use of chlorophyll and in the photosynthetic process, indicating the basal layer leaves as reference for this type of evaluation. The CWSI shows great variability throughout the cycle and indicates the red mesh environment as the most likely to cause hydric stress to plants in most of the months studied.

Em busca da máxima produtividade das culturas em ambiente protegido, muitos agricultores aplicam doses excessivas de adubos. Isto, na maioria das vezes, acarreta no aumento dos custos de produção, no baixo rendimento das culturas, contaminação ambiental e acúmulo de sais no solo, podendo torná-lo impróprio para o cultivo. Neste sentido, são realizados estudos para desenvolver um manejo da fertirrigação que propicie maior eficiência produtiva da cultura do pimentão em ambiente protegido. Neste contexto, este trabalho foi desenvolvido com o objetivo de avaliar a eficiência de manejos da fertirrigação e níveis de nitrogênio e de potássio na cultura do pimentão em ambiente protegido. O delineamento utilizado foi blocos casualizados, em esquema fatorial 3 x 6, totalizando 18 tratamentos, com quatro repetições. Os tratamentos resultaram da combinação de três manejos de fertirrigação (M1 - Fertirrigação a partir da marcha de absorção de nutrientes pela cultura; M2 - Fertirrigação a partir do monitoramento da concentração de íons de N e K na solução do solo; M3 - Fertirrigação a partir do monitoramento da condutividade elétrica da solução do solo), com seis níveis de nitrogênio e de potássio (0, 50, 100, 150, 200 e 300% da recomendação padrão para a cultura cultivada no sistema hidropônico). Para o manejo M1 foi adotada como dose padrão de N e K a recomendação destes nutrientes para a cultura do pimentão em condições de campo (100% de NK, sendo N = 16,1 e K = 23,5 g planta-1). Para os manejos M2 e M3, utilizou-se como dosagem padrão a recomendação de N e K para o cultivo hidropônico no sistema NFT (100% NK, sendo N = 152 e K = 245 mg L-1). Ao longo do ciclo da cultura foi realizado o monitoramento da concentração dos íons de N e K (M2) e da condutividade elétrica (M3) da solução coletada. Os resultados eram analisados e utilizados na tomada de decisão quanto ao momento de se fazer a fertirrigação e as quantidades de N e K a serem aplicadas. Os parâmetros avaliados foram produtividade e qualidade de frutos, além do consumo de nutrientes e de água. Avaliaram-se também, ao final do experimento, as características químicas do solo, bem como os principais índices de eficiência nutricional de N e K na cultura do pimentão. Os resultados demonstraram que a resposta das plantas à adubação mineral depende do manejo de fertirrigação. Os tratamentos afetaram a absorção de nutrientes no tecido vegetal, mas, na maioria dos casos, as concentrações de nutrientes estavam dentro da faixa considerada adequada para a cultura. Observouse também que o manejo da fertirrigação a partir do monitoramento da concentração dos íons de N e K, ou da condutividade elétrica da solução do solo foi mais eficiente que a fertirrigação realizada com base na marcha de absorção de nutrientes da cultura do pimentão, proporcionando em plantas mais desenvolvidas, mais produtivas e com maior eficiência no uso de fertilizantes. / Looking for maximum crop yield in greenhouse, several growers apply excessive nutrient doses. This behavior frequently brings increase in production costs, lower crop yields, environmental contamination and salt buildup in the soil, which can became inappropriate for cropping. With this concern, studies are made for developing fertirrigation management that improves Sweet Pepper crop efficiency in greenhouse. For these reasons, this work was carried out with the objective of evaluating fertirrigation management efficiency as well as levels of nitrogen and potassium for Sweet Pepper grown in greenhouse. Experimental design was a randomized blocks in a 3x6 factorial scheme, totaling 18 treatments, with four replications. Treatments resulted from the combination of three fertirrigation managements (M1 - Fertirrigation based on the curve of nutrient absorption of the crop; M2 - Fertirrigation based on monitoring of ions N and K in soil solution; M3 - Fertirrigation based on monitoring of electrical conductivity of soil solution) with six levels of nitrogen and potassium (0; 50; 100; 150; 200 and 300% of standard recommendation for Sweet Pepper grown in hydroponics). Standard dose of N and K adopted for M1 management was the recommendation of these nutrients for Sweet Pepper in field conditions (100% NK was: N = 16.1 and K = 23.5 g plant-1). For M2 and M3, the standard dose was the N and K recommendation for hydroponics in the NFT system (100% NK was: N = 152 e K = 245 mg L-1). During crop cycle were monitored the concentrations of N and K ion (M2) and the electric conductivity of sampled solution (M3). After analyzed, results were used for decision making on the moment of application and amounts of N and K to be applied. Parameters evaluated were those related to fruit yield and quality, as well as nutrient and water consumption. At the end of the trial were also analyzed soil chemical characteristics and the main indexes of nutritional efficiency for N and K in Sweet Pepper crop. Results showed that plant response to mineral fertilization depended on fertirrigation n management. Treatments influenced absorption of nutrients by plant tissue, but, in most cases, nutrient concentrations were in the range considered adequate for the crop. It was also observed that fertirrigation managements based on monitoring of concentration of ions N and K, or of electrical conductivity of soil solution were more efficient than the management based on nutrient absorption curve of Sweet Pepper, because they provided plants more developed and productive, with higher fertilizer use efficiency.