-The objective of this work was to evaluate the development and quality of clonal seedlings of teak (Tectona grandis) grown in substrate with two types of biochar. The assay was carried out in a randomized complete block design, with ten treatments and four replicates: CS, commercial substrate, composed of pine bark and vermiculite at a ratio of 4:1; NS, nursery substrate composed of carbonized rice husk and coconut fiber at 1:1; and the remaining treatments were composed of the inclusions of biochar (BC) or activated biochar (BCA) in the CS, at the proportions of 25, 50, 75, and 100%. The development and quality parameters of seedlings were evaluated 90 days after striking the minicuttings in the substrates. BCA substrate additions at 25, 50, and 100% allowed for a development of height and stem diameter comparable to that of the NS. Biochar without the activation procedure does not improve quality parameters of seedlings, in comparison with the commercial substrate. The use of 25% activated biochar added to the commercial substrate is enough to improve seedling growth performance to the same level as that provided by the already validated NS.Index terms: Tectona grandis, agroindustrial waste, biochar activity, pyrolysis, seedling quality. Biochar na composição de substratos para a produção de mudas de tecaResumo -O objetivo deste trabalho foi avaliar o desenvolvimento e a qualidade de mudas clonais de teca (Tectona grandis) cultivadas em substrato com dois tipos de biochar. O ensaio foi realizado em delineamento de blocos ao acaso, com dez tratamentos e quatro repetições: SC, substrato comercial, composto de casca de pinus e vermiculita à proporção de 4:1; SV, substrato do viveiro, composto de casca de arroz carbonizada e fibra de coco a 1:1; e o restante dos tratamentos foi composto de inclusões de biochar (B) e biochar ativado (BA), nas proporções de 25, 50, 75 e 100% do SC. Os parâmetros de desenvolvimento e qualidade das mudas foram avaliados 90 dias após o plantio das estacas nos substratos. A adição de 25, 50 e 100% de BA possibilitou o desenvolvimento em altura e diâmetro do coleto comparável ao proporcionado pelo SV. O biochar sem o procedimento de ativação não melhora os parâmetros de qualidade das mudas, em comparação ao substrato comercial. A adição de biochar ativado na proporção de 25% já é suficiente para melhorar o crescimento das mudas para o mesmo nível proporcionado pelo já validado SV.Termos para indexação: Tectona grandis, resíduo agroindustrial, atividade do biochar, pirólise, qualidade de mudas.

Great part of solid waste are deposited inappropriately near cities or in rural areas, contributing to negative environmental impacts. There are numerous forms of waste processing, one of them is pyrolysis to produce biochar and subsequent use in agricultural systems. The objective of this study was to evaluate different substrates with activated biochar (AB) and biochar (B) in substrate and its effect on the growth of passion fruit seedlings. The test was conducted in a nursery, located in Sinop/MT, May to July 2013, designed in four blocks with ten treatments: commercial substrate (CS), composed by pine bark and vermiculite 4:1; nursery substrate (NS) composed by carbonized rice husk and coconut fiber 1:1; and the eigth treatments represented were B and AB additions of 25; 50; 75; and 100% in CS, (B25, B50, B75, B100, AB25, AB50, AB75 and AB100, respectively). After 60 days sowing the stem diameter, plant height, leaf number was evaluated and at the end of the experiment the fresh and dry weight of shoots and roots, and Dickson Quality Index (DQI) were assessed. AB at concentrations of 25, 50 and 75% combined with commercial substrate showed increases in parameters fresh and dry biomass weight, height, stem diameter and number of leaves. The dose of 25% AB is presented as the best dose to be adopted in commercial crops. The sawdust processed into AB is an alternative in the production of passion fruit system and the reintegration of this raw material to the productive sector.

Resumo -O uso de fertilizantes com eficiência aumentada tem crescido nos últimos anos, e o setor de produção de mudas florestais pode ser um dos beneficiados por essas tecnologias. Este estudo teve o objetivo de avaliar a eficiência de fertilizantes organominerais fosfatados sobre o desenvolvimento inicial de mudas de eucalipto. O experimento foi realizado em viveiro florestal localizado no município de Sinop(MT), em tubetes de 50 cm³. Foram avaliados três fertilizantes organominerais fosfatados, em um delineamento em blocos casualizados, formulados a partir da mistura e granulação, em diferentes proporções, de superfosfato triplo, fosfato natural reativo de Bayovar, conteúdo ruminal de bovinos de corte, biochar e cama-de-aviário. Essas fontes foram granuladas e aplicadas em um substrato comercial, em quatro níveis de fósforo (1,4; 2,5; 3,6 e 4,7 mg planta -1 ) mais um tratamento referência. As parcelas experimentais foram compostas por 16 mudas do clone de eucalipto (Urograndis -I144), com quatro repetições. Aos 70 dias foi determinada a massa seca da parte aérea (MSPA), massa seca de raízes (MSR), teor de fósforo na parte aérea e o índice de eficiência agronômica. A produção de MSPA e MSR foi superior nas mudas com aplicação de fertilizante organomineral granulado com fosfato natural reativo de Bayovar e conteúdo ruminal. Esse fertilizante apresentou eficiência similar ao tratamento referência, podendo ser uma alternativa para a utilização na produção de mudas de eucalipto. O fertilizante organomineral granulado com superfosfato triplo, biochar e cama-deaviário não foi eficiente para o desenvolvimento inicial de mudas de eucalipto. Palavras-chave: conteúdo ruminal, fosfato de Bayovar, biochar.Abstract -The use of fertilizers more efficient has grown in the last years, and the seedlings production sector can be one of those benefited by these technologies. The objective of this study was to evaluate the efficiency of phosphate organomineral fertilizers on eucalyptus seedlings development. The experiment was set up in a nursery located in Sinop, state of Mato Grosso, Brazil, in 50 cm³ tubes. Three phosphate organomineral fertilizers were evaluated in a randomized block design, formulated from the mixture and granulation, in different proportions, of triple superphosphate, reactive natural phosphate from Bayovar, ruminal content of beef cattle, biochar and poultry. These sources were granulated and applied in a commercial substrate in four phosphorus levels (1.4, 2.5, 3.6 and 4.7 mg plant -1 ) plus a reference treatment. The experimental plots were composed of 16 seedlings of eucalyptus clone (Urograndis -I144), with four replications. At 70 days the shoot and root dry mass, phosphorus content in shoot and the agronomic index were determined. Root and shoot production was higher in the seedling fertilized with Bayovar reactive natural phosphate granulated with ruminal content. This fertilizer could be use in seedling production. The organomineral fertilizer granulated with triple superphosphate, biochar and poult...

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The search for new substrates for the production of seedlings is of great importance for the evolution of the nursery sector. Biochar is an alternative for the use of plant residues, both in soils and as a component of substrates. The main objective of the study was to correlate substrates using biochar (B) and substrates using activated biochar (AB) in different concentrations with biometric and nutritional variables, aside from its effect on the growth of Eucalyptus seedlings. The experiment was conducted in a nursery, located in Sinop, MT, Brazil. The experiment was design in four blocks of ten treatments; commercial substrates (CS), nursery substrate (NS-50% CS and 50% carbonized rice husk and coconut fiber) and eight treatments represented by B and AB additions to each commercial substrate (concentration of 25; 50, 75 and 100%-determined as B25, B50, B75, B100, AB25, AB50, AB75, AB100). At the end of a 90 days cycle after staking, plant height, stem diameter, leaf number and Dickson Quality Index (DQI), fresh and dry biomass accumulation and nutrient concentration in the aerial part were determined. The substrates with activated biochar and the nursery substrate presented superior results for biometric variables.

Leaching and nitrous oxide (N2O) emissions can represent substantial nitrogen (N) losses from chemical fertilizers, and slow-release fertilizers (SRFs) can mitigate these effects. Thus, biochar can be an alternative from an agronomic and environmental point of view to synthesize SRFs due to its physicochemical characteristics. We investigated the effect of nitrogenous organomineral fertilizers (OMF-N) formulated based on activated biochar on N losses by leaching and N2O emissions. The OMF-N were developed from a dry mechanical pelleting process with different biochar and urea proportions (2:1; 1:2, and 1:4). Three experiments were conducted using four fertilizer sources (urea, OMF-N 2:1, OMF-N 1:2, and OMF-N 1:4): i. to analyze the kinetics of N release from OMF-N at times: 5, 15, 30, 60, 90, and 120 min; ii. for N2O emission analysis determined at 3, 6, 10, 14, 24, 44, 54, 64, 74, 84, 104, and 118 days after application to the soil; and iii. for a double factorial design that was adopted to analyze N leaching, consisting of the combination of applying 160 kg N ha−1 of fertilizers in PVC columns at different depths (20, 40, 60, and 80 cm) and analyzed at five times (1, 7, 14, 21, and 28 days). FTIR spectroscopic analysis, specific surface area, porosity, and surface morphology showed physicochemical interactions of N of the OMF with biochar; the N from the OMF interacts physically and chemically binds to the functional surfaces of biochar, delaying the dissolution flow. The OMF-N proved capable of retaining 48% to 60% more NH4+ and reduced the release of Ntotal from urea from 27% to 60%, as well as reduced N2O emissions from 47% to 66%. Although absolute CO2 emissions intensified with the application of OMF-N, its use provides C sequestration in the soil to due to the recalcitrant C of the biochar, which results in a positive input-output balance in the system. The NO3− concentration profiles revealed that the OMF-N application was able to reduce leaching in the soil to a depth of 80 cm. These studies enabled better understanding of the processes involved in the biochar:urea interaction and revealed that biochar can be used as an organic matrix in the synthesis of SRF.

A preocupação mundial, relativa à busca de alternativas aos combustíveis fósseis, vem encontrando soluções nos campos agrícolas e no uso de resíduos para produção de biodiesel. Objetivou-se com este trabalho verificar a melhor composição de substratos para compostagem da borra resultante da extração do biodiesel de gorduras e óleos residuários de frituras de alimentos. Dois experimentos foram realizados, um em campo e outro em casa de vegetação. O experimento de campo foi implantado a fim de obter composto orgânico a partir de capim napier picado, adicionado ao esterco bovino ou resíduo de mamona, utilizando diferentes doses da borra de óleos de frituras de alimentos. O experimento em estufa foi realizado a fim de testar os compostos provenientes da etapa de campo, a planta teste utilizada foi sorgo. A borra, nas doses utilizadas, pode ser reciclada por meio de compostagem sem afetar o produto final. Compostos de capim napier com esterco de bovinos apresentam condutividade eletrolítica mais adequada que compostos de capim napier com torta de mamona. Adição de torta de mamona ao composto resultou em produtos finais mais ricos nutricionalmente. Compostos de capim napier com torta de mamona, propiciaram maior produção de biomassa que os de capim napier com esterco.