RESUMO
In addition to playing a key role in the response to environmental changes, cell walls are also considered as a valuable feedstock for cellulosic ethanol. Here we explored the effects of the stress-response hormones, salicylic acid and methyl jasmonate, on cell wall biosynthesis and biomass digestibility in Brachypodium distachyon, a species recently considered as a suitable model for biomass conversion. We found that in response to salicylic acid or methyl jasmonate treatment, plant growth was reduced coupled with significant changes in cell wall composition. Cellulose content increased in response to methyl jasmonate whereas a reduction in lignin content was found after salicylic acid application. Moreover, hemicellulose composition was altered and increases in caffeic acid, ferulic acid and p-coumaric acid content were detected in response to both treatments. The hormonal profile and the expression pattern of genes involved in cell wall biosynthesis were also modified. Biomass digestibility was reduced in leaf tissue after salicylic acid treatment and was negatively correlated with ferulic acid and p-coumaric acid content. The results obtained here aid in our understanding of cell wall dynamics in response to stress and will enable the development of new strategies to improve cell wall digestibility in bioenergy feedstock.
Assuntos
Acetatos/farmacologia , Brachypodium/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Ácido Salicílico/farmacologia , Biomassa , Brachypodium/crescimento & desenvolvimento , Brachypodium/fisiologia , Parede Celular/química , Parede Celular/metabolismo , Celulose/metabolismo , Ácidos Cumáricos/metabolismo , Lignina/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Caules de Planta/efeitos dos fármacos , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/fisiologia , Polissacarídeos/metabolismo , Propionatos/metabolismo , Estresse FisiológicoRESUMO
The aim of this study was to evaluate the phosphorus (P) mobility in a tropical Brazilian soil type red Oxisol treated with three different forms of granular fertilizer. Total Reflection X-Ray Fluorescence (TXRF) was applied to determine the concentration of P at different distances from granular fertilizer application point. The results showed that most of the P from fertilizers tends to concentrate in a region of up to 10mm around the place of the fertilizer deposition.
RESUMO
RESUMO O objetivo deste estudo de caso único é descrever e avaliar a aplicação de um modelo de Intervenção Comportamental Intensiva, realizado por meio da capacitação dos cuidadores, com uma criança com autismo gravemente comprometida e não falante. A intervenção ocorreu por 40 horas semanais em ambiente domiciliar e escolar, ao longo de cinco anos consecutivos. Instrumentos padronizados foram utilizados para medir o desenvolvimento da criança. Os resultados gerais indicaram ganhos no desenvolvimento da criança e a viabilidade da capacitação dos cuidadores para esse tipo de intervenção.
ABSTRACT The purpose of this single case study is to describe and evaluate the application of an Intensive Behavioral Intervention model, carried out through the training of caregivers, with a child with severely compromised and non-speaking autism. The intervention occurred for 40 hours a week in a home and school environment, during five consecutive years. Standardized instruments were used to measure child development. Overall results indicated gains in child development and the feasibility of training of caregivers for this type of intervention.