Nas últimas duas décadas a produção de alimentos utilizando menos insumos sintéticos tem atraído a atenção em muitos campos, como indústria e pesquisa. Esta forma de produção é conhecida como agricultura orgânica e enaltece a ausência de produtos químicos industrializados no sistema produtivo agropecuário. Uma prática útil e de baixo custo é o emprego de biofertilizantes, principalmente pelo fato da crescente procura por tecnologias de produção que apresentem redução de custos e uma melhora na qualidade de vida. Esses fatos, contudo, têm incentivado pesquisadores e produtores rurais a experimentarem biofertilizantes preparados a partir da digestão aeróbia ou anaeróbia de materiais orgânicos em substituição aos fertilizantes minerais. Biofertilizante é a designação dada ao efluente líquido obtido da fermentação aeróbia ou anaeróbia da matéria orgânica e água, cujo produto final contém células vivas ou latentes de microrganismos. Assim, neste trabalho, os biofertilizantes foram preparados a partir dos resíduos orgânicos em quatro misturas (esterco bovino + bagaço de laranja (M1); cama de frango + bagaço de laranja (M2); esterco bovino + cama de frango (M3) e esterco bovino + cama de frango + bagaço de laranja (M4), que foram caracterizados em diversas etapas quanto à acidez, condutividade elétrica, concentração de macro e micronutrientes, teor de matéria orgânica e de substâncias húmicas, atributos de qualidade sanitária (coliformes termotolerantes, totais e E. colli) dentre outros e foi testado o potencial agronômico de biofertilizantes associados ao sistema convencional de manejo e a técnica do cultivo hidropônico, com o objetivo de contribuir para o menor consumo de reservas naturais de nutrientes do planeta. Os resultados mostraram que a mistura M3 produziu o melhor biofertilizante por obter os melhores resultados biométricos quando aplicado à cultura, demonstrando que foi possível a produção de um bom biofertilizante em relação ao potencial agronômico. / In the last two decades, there has been a worldwide trend in producing food using less synthetic inputs. This form of production is known as organic agriculture and it praises the absence of industrialized chemicals in the agricultural production system. A useful and low-cost practice is the use of biofertilizers, mainly due to the growing demand for production technologies that reduce costs and provide a better quality of life. However, those facts have encouraged researchers and farmers to experiment biofertilizers prepared from aerobic or anaerobic digestion of organic materials instead of mineral fertilizers. Biofertilizer is the name given to the liquid effluent obtained from aerobic or anaerobic fermentation of organic material and water, and the final product contains live cells or latent microorganisms. In this work, the biofertilizers were prepared from the organic residues in four mixtures (cow manure + orange bagasse (M1), poultry + orange bagasse (M2), cow manure + poultry (M3) and cow manure + poultry + orange bagasse (M4)), which were characterized in several stages regarding acidity, electrical conductivity, concentration of macro and micronutrients, organic material and humic substances content, antibacterial activity (thermotolerant coliforms, total and e-coli) among others, to test the agronomic potential of biofertilizers associated with the conventional management system and the hydroponic cultivation technique, in order to contribute to a lower consumption of natural nutrients reserves from the planet. The results showed that the mixture M3 produced the best biofertilizer, because of the biometric results when it was applied to the crop, demonstrating to be a successful biofertilizer in terms of agronomic potential.

Nas últimas duas décadas a produção de alimentos utilizando menos insumos sintéticos tem atraído a atenção em muitos campos, como indústria e pesquisa. Esta forma de produção é conhecida como agricultura orgânica e enaltece a ausência de produtos químicos industrializados no sistema produtivo agropecuário. Uma prática útil e de baixo custo é o emprego de biofertilizantes, principalmente pelo fato da crescente procura por tecnologias de produção que apresentem redução de custos e uma melhora na qualidade de vida. Esses fatos, contudo, têm incentivado pesquisadores e produtores rurais a experimentarem biofertilizantes preparados a partir da digestão aeróbia ou anaeróbia de materiais orgânicos em substituição aos fertilizantes minerais. Biofertilizante é a designação dada ao efluente líquido obtido da fermentação aeróbia ou anaeróbia da matéria orgânica e água, cujo produto final contém células vivas ou latentes de microrganismos. Assim, neste trabalho, os biofertilizantes foram preparados a partir dos resíduos orgânicos em quatro misturas (esterco bovino + bagaço de laranja (M1); cama de frango + bagaço de laranja (M2); esterco bovino + cama de frango (M3) e esterco bovino + cama de frango + bagaço de laranja (M4), que foram caracterizados em diversas etapas quanto à acidez, condutividade elétrica, concentração de macro e micronutrientes, teor de matéria orgânica e de substâncias húmicas, atributos de qualidade sanitária (coliformes termotolerantes, totais e E. colli) dentre outros e foi testado o potencial agronômico de biofertilizantes associados ao sistema convencional de manejo e a técnica do cultivo hidropônico, com o objetivo de contribuir para o menor consumo de reservas naturais de nutrientes do planeta. Os resultados mostraram que a mistura M3 produziu o melhor biofertilizante por obter os melhores resultados biométricos quando aplicado à cultura, demonstrando que foi possível a produção de um bom biofertilizante em relação ao potencial agronômico. / In the last two decades, there has been a worldwide trend in producing food using less synthetic inputs. This form of production is known as organic agriculture and it praises the absence of industrialized chemicals in the agricultural production system. A useful and low-cost practice is the use of biofertilizers, mainly due to the growing demand for production technologies that reduce costs and provide a better quality of life. However, those facts have encouraged researchers and farmers to experiment biofertilizers prepared from aerobic or anaerobic digestion of organic materials instead of mineral fertilizers. Biofertilizer is the name given to the liquid effluent obtained from aerobic or anaerobic fermentation of organic material and water, and the final product contains live cells or latent microorganisms. In this work, the biofertilizers were prepared from the organic residues in four mixtures (cow manure + orange bagasse (M1), poultry + orange bagasse (M2), cow manure + poultry (M3) and cow manure + poultry + orange bagasse (M4)), which were characterized in several stages regarding acidity, electrical conductivity, concentration of macro and micronutrients, organic material and humic substances content, antibacterial activity (thermotolerant coliforms, total and e-coli) among others, to test the agronomic potential of biofertilizers associated with the conventional management system and the hydroponic cultivation technique, in order to contribute to a lower consumption of natural nutrients reserves from the planet. The results showed that the mixture M3 produced the best biofertilizer, because of the biometric results when it was applied to the crop, demonstrating to be a successful biofertilizer in terms of agronomic potential.

The long-term effects of low and high NH4+/ NO3- uptake ratios in a system with rigorous control of pH and nitrogen concentration are poorly understood. In two replicate studies, two cultivars of wheat (Triticum aestivum) were grown to maturity with three NH4+/ NO3- ratios in hydroponic solution: 0/100, 25/75, and 85/15%. Nitrogen was controlled at ample levels throughout the 70-d life cycle and pH was controlled at 5.8 ± 0.2. An equimolar ratio of NH4+ to Cl- was used to facilitate charge balance. Nitrogen consumption and transpiration were measured daily. Flag leaves were analyzed at 10-d intervals for total nitrogen, NO3--N, and essential elements. Essential nutrient elements in the biomass and seeds were measured at harvest. Yield components , nitrogen recovery, and nitrogen assimilation were calculated. There was no difference between the NO3- only (0/100) and the low NH4+ (25/75) treatments . The high NH4+ treatment (85/15) did not reduce vegetative biomass, but decreased seed yield and harvest index by 20%. The decrease was associated with a 23% reduction in seed number head-1. The high NH4+ treatment increased percent root mass by 50% and percent sterile heads by 800%, but increased assimilated N in the seeds by 30% and in the biomass by 130%. Supplemental additions of K were effective in preventing the reduction of K concentration in the wheat tissues typically caused by high NH4+, but the high NH4+ treatment decreased the concentrations of Ca, Mn, and Zn, and increased the concentrations of S, P, Fe, and B in the wheat tissue . The uptake of Mg and Cu was similar among all three treatments. Chloride concentrations in the flag leaves increased from 0.8% in the NO3- only treatment to 2.0% in the two NH4+ treatments. This research indicates that hydroponic wheat can be grown to maturity with high levels of NH4+ with a small reduction in grain yield.

Soil salinity affects over 20% of the worlds irrigated land. Potato (Solanum tuberosum L.), the most important vegetable crop worldwide, is relatively salt sensitive. However, relatively little work has been done on salt tolerance of the potato plant. This thesis investigated the methodology of treatment application and scion/rootstock effects on subsequent salt stress responses of four contrasting potato genotypes: Norland, 9506, 9120-05 [ABA-deficient mutant], and 9120-18 [ABA-normal sibling] grown hydroponically in sand. The effect of incremental salt stress were studied, using NaCl, CaCl2 and combined NaCl + CaCl2 pre- treatments as well as varying methods of ABA application with a specific focus on the role of rootstock and scion. Physiological responses of various potato genotypes to salt stress differed depending on how the salt stress was applied. An incremental salt stress regime was able to more effectively differentiate genotypes based on salt stress resistance and greater salt tolerance compared to a sudden salt shock. Generally, the ability to produce ABA was positively related to the degree of salt stress resistance, with higher ABA levels induced under incremental salt stress treatments compared to salt shock. The method of ABA application also had a marked effect on potato responses to salt stress. Slowly increasing concentrations of exogenous ABA maintained growth rates, enhanced root water content and induced more lateral shoot growth compared to a single ABA dose. The degree of salt tolerance induced by the grafted rootstock was primarily modulated by salt acclimation and was manifested in the scion as increased water content, stem diameter, dry matter accumulation, stomatal conductivity, and osmotic potential and was associated with reduced leaf necrosis. Using the salt-resistant 9506 line as a scion also significantly increased root fresh and dry weight and stem diameter as well as root water content of salt-sensitive ABA-deficient mutant rootstocks. Exogenous ABA appeared to enhance plant water status via the roots under salt stress beyond that of grafting alone. This was verified by more positive stomatal conductivity and greater upward water flow in ABA treated grafted and non-grafted plants as compared to the absence of upward water flow in non-treated grafted plants as measured via micro NMR imaging. NaCl pre-treatment produced greater salt stress resistance compared to pre-treatment with CaCl2 and was associated with a specific Na+ ion effect rather than a non-specific EC-dependent response. However, the presence of both ABA and CaCl2 appears to be necessary in order to enhance Na+ exclusion from the shoot and increases the K+/Na+ ratio.

Soil salinity affects over 20% of the worlds irrigated land. Potato (Solanum tuberosum L.), the most important vegetable crop worldwide, is relatively salt sensitive. However, relatively little work has been done on salt tolerance of the potato plant. This thesis investigated the methodology of treatment application and scion/rootstock effects on subsequent salt stress responses of four contrasting potato genotypes: Norland, 9506, 9120-05 [ABA-deficient mutant], and 9120-18 [ABA-normal sibling] grown hydroponically in sand. The effect of incremental salt stress were studied, using NaCl, CaCl2 and combined NaCl + CaCl2 pre- treatments as well as varying methods of ABA application with a specific focus on the role of rootstock and scion. Physiological responses of various potato genotypes to salt stress differed depending on how the salt stress was applied. An incremental salt stress regime was able to more effectively differentiate genotypes based on salt stress resistance and greater salt tolerance compared to a sudden salt shock. Generally, the ability to produce ABA was positively related to the degree of salt stress resistance, with higher ABA levels induced under incremental salt stress treatments compared to salt shock. The method of ABA application also had a marked effect on potato responses to salt stress. Slowly increasing concentrations of exogenous ABA maintained growth rates, enhanced root water content and induced more lateral shoot growth compared to a single ABA dose. The degree of salt tolerance induced by the grafted rootstock was primarily modulated by salt acclimation and was manifested in the scion as increased water content, stem diameter, dry matter accumulation, stomatal conductivity, and osmotic potential and was associated with reduced leaf necrosis. Using the salt-resistant 9506 line as a scion also significantly increased root fresh and dry weight and stem diameter as well as root water content of salt-sensitive ABA-deficient mutant rootstocks. Exogenous ABA appeared to enhance plant water status via the roots under salt stress beyond that of grafting alone. This was verified by more positive stomatal conductivity and greater upward water flow in ABA treated grafted and non-grafted plants as compared to the absence of upward water flow in non-treated grafted plants as measured via micro NMR imaging. NaCl pre-treatment produced greater salt stress resistance compared to pre-treatment with CaCl2 and was associated with a specific Na+ ion effect rather than a non-specific EC-dependent response. However, the presence of both ABA and CaCl2 appears to be necessary in order to enhance Na+ exclusion from the shoot and increases the K+/Na+ ratio.

This thesis is the first report linking differential distribution of cadmium (Cd) among tissues of hydroponically-grown soybean with Cd amendments – lower seed Cd-accumulating OAC Champion and higher seed Cd-accumulating OAC Bayfield – and the mechanisms responsible for these differences. OAC Champion retains 94% (64% for OAC Bayfield) of accumulated Cd in the root stock and Cd in its xylem sap is eleven-fold less concentrated than OAC Bayfield by seed fill. Though the movement of Cd to shoots is more restricted in OAC Champion, the concentration in some seed still approximates or exceeds 0.1 mg Cd • kg-1, indicating that in soils with elevated available Cd, there is potential for many cultivars of soybean to exceed the new suggested maximum for soybean, under an amendment to regulation (EC) No 1881/2006. Phytic acid was also assayed in seed tissue and OAC Bayfield was found to contain the highest concentrations.

Traditionally, the condition of hydroponic nutrient solutions used in controlled environment or greenhouse plant production is obtained by monitoring solution pH and electrical conductivity. These parameters provide greenhouse operators with an overall sense of the solution quality, but do not provide information on individual components of the fertilizer solution. Considering that plant nutrient uptake requirements vary with crop, growth phase and environment, real-time ion-selective measurements represent a significant technological advance in the management of recirculating nutrient solutions. The capacity for the monitoring and control of individual ions in the nutrient solution is the last remaining environment variable for which reliable feedback control does not exist in controlled environment plant production. This technology development study focussed on optical ion-selective sensors, termed ‘optrodes’, for potassium and calcium sensing within nutrient solution. Bulk optrode absorption-based sensors, tailored explicitly for nutrient ion activities within typical hydroponic solutions were theoretically modelled, fabricated and experimentally tested. Experimental data on sensor response time, measuring range, selectivity, repeatability, lifetime and influence of temperature were compiled. These ion-selective bulk optrode membranes were integrated into a custom instrument combining a light source, mini-spectrometer, optical fibres and other associated components. Monitoring and control software was written that collected and converted optical measurements into estimated nutrient ion activities for use in managing nutrient solution quality. Implemented spectral averaging, normalization and ratiometric computations and techniques resulted in sensors that offered the advantage of auto-calibration. The sensors met selectivity requirements in half strength Hoagland nutrient solution and provided repeatable measurements in solutions of different ion activity levels. Potassium and calcium selective membranes demonstrated lifetimes of 30 to 50 hours when constantly immersed in nutrient solution. Strategies for their operational implementation in plant growth systems based upon experimental testing are proposed as are suggestions for future study. The low mass, low volume, low cost and robust nature of these optrodes offer a promising technology for future space-based plant production systems and give them excellent terrestrial technology transfer potential.

Made available in DSpace on 2014-06-11T19:34:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-12-17Bitstream added on 2014-06-13T19:24:04Z : No. of bitstreams: 1 correa_eb_dr_botfca.pdf: 989982 bytes, checksum: 71fbc2f45208972feb39e1343c4e6620 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O cultivo hidropônico de hortaliças vem crescendo e se tecnificando no Brasil. No entanto, podridões radiculares causadas por espécies de Pythium constituem um sério problema para a sua expansão. Uma vez o patógeno instalado no sistema, esse pode ser suprimido por meio da adição de microrganismos antagônicos. Além de suprimirem a podridão radicular, esses microrganismos introduzidos na solução nutritiva podem promover o crescimento das plantas, aumentando a receita do produtor. Entretanto, muitas vezes verifica-se baixa sobrevivência dos microrganismos adicionados na solução nutritiva. O desenvolvimento de formulações de agentes de controle biológico, principalmente de bactérias do gênero Pseudomonas, é um fator chave para a sua utilização em escala comercial. Devido à importância da podridão radicular em cultivos hidropônicos e o potencial de utilização do controle biológico da doença, os objetivos do presente trabalho foram (i) selecionar microrganismos residentes do manguezal como agentes de biocontrole da podridão radicular e promotores de crescimento em pepino hidropônico; (ii) avaliar o controle biológico da podridão radicular e a promoção de crescimento por Pseudomonas chlororaphis 63-28 e Bacillus subtilis GB03 em pimentão e alface cultivados em hidroponia; (iii) desenvolver uma formulação de Pseudomonas spp.. Em condições de casa de vegetação, Bacillus cereus AVIC-3-6, isolado de manguezal, protegeu as plantas de pepino do subdesenvolvimento causado pelo patógeno; Gordonia rubripertincta SO-3B-2 e Pseudomonas stutzeri MB-P3A-49, também isolados de manguezal, promoveram o crescimento de plantas de pepino não inoculadas com o patógeno. A adição de P. chlororaphis 63-28 e B. subtilis GB03 na solução nutritiva de pimentão cultivado em hidroponia e inoculado com P. aphanidermatum teve efeito positivo na supressão dos danos causados... / Hydroponic production of vegetables and flowers is increasing in Brazil, and the production technology is improving. A major factor constraining crop productivity is root rot caused by Pythium spp. Root rot severity can be reduced by the application of appropriate antagonistic microbes into the hydroponic nutrient solution or root zone of the crops. When in the root zone beneficial microbes may suppress progress of the root rot and increase crop productivity. However some beneficial microbes are not well-adapted to hydroponic environments and do not survive well in plant nutrient solutions. Ecologically-adapted microbes that are effective against root rot are a key factor for successful root rot control in hydroponic crops. The need for effective biological agents that are adapted to hydroponic systems and appropriately formulated for commercial use prompted investigations with the following aims: i) to select bacterial strains from among isolates obtained from mangrove swamps for effectiveness in controlling Pythium root rot in hydroponic cucumber; ii) to evaluate Pseudomonas chlororaphis 63-28 and Bacillus subtilis GB03 for controlling root rot and promoting growth of hydroponic lettuce and pepper; and iii) to assess formulations of Pseudomonas spp. for long-term shelf life. Bacillus cereus AVIC -3-6 from a mangrove reduced stunting of hydroponic cucumbers associated with Pythium root rot. Gordonia rubripertincta SO-3B-2 and Pseudomonas stutzeri MB-3PA-49 from a mangrove increased growth of healthy cucumber plants. Application of Pseudomonas chlororaphis 63-28 and Bacillus subtilis GB03 into the nutrient solution of hydroponic pepper suppressed root rot and increase the plant growth. Among tested formulations of Pseudomonas chlororaphis 63-28, a formulation with coconut fibre of 80% moisture content had the longest shelf life (up to 32 weeks) when kept at at 3ºC. We conclude that a)... (Complete abstract click electronic access below)

Made available in DSpace on 2016-06-02T18:55:29Z (GMT). No. of bitstreams: 1 6677.pdf: 2112250 bytes, checksum: 23a60ac90f07a90b3b304868be4c948b (MD5) Previous issue date: 2015-02-06 / The water for many years was considered inexhaustible, and only in recent decades, became aware of the shortage and the need to rationalize their use, look for ways to reuse and recovery of its quality. In this search context for reuse alternatives, the use of treated sewage sludge in agriculture can become an important tool in water management. Therefore this study evaluated the production of lettuce (Lactuca sativa L.) using hydroponic reuse water from sewage treatment plant. The experiment was conducted at Agricultural Science Center - UFSCar, in Araras, SP, in the greenhouse. Crops occurred from February to March (summer) and July-August (winter) 2014. The hydroponic system adopted was the Nutrient Film Technique (NFT), three treatments, with the first supply of water and fertilizers (TA ), the second with sewage treated and supplemented with fertilizers according to results of previous chemical analysis (TRA), and the third only treated sewage (TR), distributed in four randomized blocks. Each treatment consisted of four plots (stands), a 500 L tank for storing the nutrient solution, a motor pump assembly and a timer. Four polypropylene hydroponic profiles with 3 meters long were used in each bench, with 48 plants per plot, totaling 192 plants per treatment. We evaluated the fresh weight, nutritional status and the microbiological quality culture, and the amount of fertilizer used in the treatments. The fresh weights were subjected to analysis of variance and means compared by Tukey test at 5% probability. Only the TR treatment showed a significant difference compared to the other, in which the plants showed symptoms of deficiency and have significant reduction in fresh weight (p <0.01). There was no detectable presence of E.coli in any treatment, and it was possible to obtain a saving of fertilizers in some of TRA compared to TR. These results suggest the feasibility of reusing water application as a water source for hydroponics, with the necessary corrections, and that the hydroponic profile can act as a barrier to prevent contact of the effluent with the lettuce leaves, according to the conditions and care adopted in handling. / A água durante muitos anos foi considerada inesgotável, e, somente nas últimas décadas, tomou-se consciência da situação de escassez e da necessidade de racionalizar seu uso, procurar formas de reúso e recuperação da sua qualidade. Neste contexto de busca por alternativas de reúso, o uso de efluentes de esgotos tratados na agricultura pode se tornar importante ferramenta no gerenciamento da água. Portanto este trabalho avaliou a produção de alface (Lactuca sativa, L.) hidropônica usando água de reúso proveniente de estação de tratamento de esgoto. O experimento foi realizado no Centro de Ciências Agrárias - UFSCar, no município de Araras, SP, em casa de vegetação. Os cultivos ocorreram de fevereiro a março (verão) e de julho a agosto (inverno) de 2014. O sistema hidropônico adotado foi a Técnica do Fluxo de Nutrientes (NFT), sendo três tratamentos, o primeiro com água de abastecimento e fertilizantes (TA), o segundo com água de esgoto tratada e complementada com fertilizantes de acordo com resultados de análise química prévia (TRA), e o terceiro somente água de esgoto tratada (TR), distribuídos em quatro blocos ao acaso. Cada tratamento foi composto por quatro parcelas (bancadas), um reservatório de 500 L para armazenar a solução nutritiva, um conjunto moto bomba e um temporizador. Foram utilizados quatro perfis hidropônicos de polipropileno com 3 metros de comprimento em cada bancada, com 48 plantas por parcela, totalizando 192 plantas por tratamento. Avaliou-se a massa fresca, o estado nutricional e a qualidade microbiológica cultura, e a quantidade de fertilizantes usados nos tratamentos. Os valores de massa fresca foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Apenas o tratamento TR apresentou diferença significativa em relação aos demais, no qual as plantas apresentaram sintomas de deficiência e tiverem redução na massa fresca significativa (p<0,01). Não foi detectado presença de E. coli em nenhum dos tratamentos, e foi possível obter uma economia de alguns de fertilizantes no TRA em comparação ao TA. Esses resultados sugerem a viabilidade da aplicação de água de reúso como fonte de água para a hidroponia, com as correções necessárias, e que o perfil hidropônico pode atuar como uma barreira para impedir o contato do efluente com as folhas de alface, de acordo com as condições e cuidados adotados na manipulação.

Resumo: O cultivo hidropônico de hortaliças vem crescendo e se tecnificando no Brasil. No entanto, podridões radiculares causadas por espécies de Pythium constituem um sério problema para a sua expansão. Uma vez o patógeno instalado no sistema, esse pode ser suprimido por meio da adição de microrganismos antagônicos. Além de suprimirem a podridão radicular, esses microrganismos introduzidos na solução nutritiva podem promover o crescimento das plantas, aumentando a receita do produtor. Entretanto, muitas vezes verifica-se baixa sobrevivência dos microrganismos adicionados na solução nutritiva. O desenvolvimento de formulações de agentes de controle biológico, principalmente de bactérias do gênero Pseudomonas, é um fator chave para a sua utilização em escala comercial. Devido à importância da podridão radicular em cultivos hidropônicos e o potencial de utilização do controle biológico da doença, os objetivos do presente trabalho foram (i) selecionar microrganismos residentes do manguezal como agentes de biocontrole da podridão radicular e promotores de crescimento em pepino hidropônico; (ii) avaliar o controle biológico da podridão radicular e a promoção de crescimento por Pseudomonas chlororaphis 63-28 e Bacillus subtilis GB03 em pimentão e alface cultivados em hidroponia; (iii) desenvolver uma formulação de Pseudomonas spp.. Em condições de casa de vegetação, Bacillus cereus AVIC-3-6, isolado de manguezal, protegeu as plantas de pepino do subdesenvolvimento causado pelo patógeno; Gordonia rubripertincta SO-3B-2 e Pseudomonas stutzeri MB-P3A-49, também isolados de manguezal, promoveram o crescimento de plantas de pepino não inoculadas com o patógeno. A adição de P. chlororaphis 63-28 e B. subtilis GB03 na solução nutritiva de pimentão cultivado em hidroponia e inoculado com P. aphanidermatum teve efeito positivo na supressão dos danos causados... (Resumop completo, clicar acesso eletrônico abaixo) / Abstract: Hydroponic production of vegetables and flowers is increasing in Brazil, and the production technology is improving. A major factor constraining crop productivity is root rot caused by Pythium spp. Root rot severity can be reduced by the application of appropriate antagonistic microbes into the hydroponic nutrient solution or root zone of the crops. When in the root zone beneficial microbes may suppress progress of the root rot and increase crop productivity. However some beneficial microbes are not well-adapted to hydroponic environments and do not survive well in plant nutrient solutions. Ecologically-adapted microbes that are effective against root rot are a key factor for successful root rot control in hydroponic crops. The need for effective biological agents that are adapted to hydroponic systems and appropriately formulated for commercial use prompted investigations with the following aims: i) to select bacterial strains from among isolates obtained from mangrove swamps for effectiveness in controlling Pythium root rot in hydroponic cucumber; ii) to evaluate Pseudomonas chlororaphis 63-28 and Bacillus subtilis GB03 for controlling root rot and promoting growth of hydroponic lettuce and pepper; and iii) to assess formulations of Pseudomonas spp. for long-term shelf life. Bacillus cereus AVIC -3-6 from a mangrove reduced stunting of hydroponic cucumbers associated with Pythium root rot. Gordonia rubripertincta SO-3B-2 and Pseudomonas stutzeri MB-3PA-49 from a mangrove increased growth of healthy cucumber plants. Application of Pseudomonas chlororaphis 63-28 and Bacillus subtilis GB03 into the nutrient solution of hydroponic pepper suppressed root rot and increase the plant growth. Among tested formulations of Pseudomonas chlororaphis 63-28, a formulation with coconut fibre of 80% moisture content had the longest shelf life (up to 32 weeks) when kept at at 3ºC. We conclude that a)... (Complete abstract click electronic access below) / Orientador: Wagner Bettiol / Coorientador: John Clifford Sutton / Banca: Antonio Carlos Maringoni / Banca: Edson Luiz Furtado / Banca: Marcelo Augusto Boechat Morandi / Doutor