290 research outputs found
Análise de características da cortiça amadia relevantes para a sua qualidade industrial
Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de AgronomiaIn this work it was studied the quality of cork from the industrial point of view. A group of
cork planks was boiled during one hour, and it resulted in an average thickness increase of
12,5%. It was studied the morphology of the main defects that cork generally presents, as
the “nail” and lenticular chanels. Porosity was measured by means of an image analysis
software, first considering only pores larger than 300 pixels (1,15mm2) and then considering
pores larger than 1000 pixels (3,84mm2). Porosity measurement of corks with higher quality
showed to be more affected by the minimum area considered as a pore. It was tried to find a
relation between porosity in tangencial and non-tangencial sections, for each one of the
following minimum pore areas: 200, 400, 600, 800 and 1000 pixels. No significant correlation
was found. Nevertheless, the best correlation results were obtained when the porosity
coefficient in non-tangencial section was ploted against the pores average area in tangencial
section. It was also created an expression with the objective to quantify cork quality in terms
of its porosity coefficient, pores average area and pores frequency.
---------------------------------------------Neste trabalho procurou-se estudar a qualidade da cortiça do ponto de vista industrial.
Cozeu-se um conjunto de cortiças, donde resultou um aumento médio em espessura de
12,5%. Estudou-se a morfologia dos principais defeitos das cortiças, nomeadamente o
“prego” e os canais lenticulares. Mediu-se a porosidade das cortiças cozidas com recurso a
um software de análise de imagem considerando apenas os poros de área superior a 300
pixeis (1,15mm2) e de seguida considerando apenas os poros de área superior a 1000 pixeis
(3,84mm2). As cortiças de melhor qualidade foram as mais afectadas pela alteração da área
mínima detectável. Procurou-se encontrar uma relação entre a porosidade nos planos
tangencial e não-tangencial, quando a área mínima detectável dos poros foi 200, 400, 600,
800 e 1000 pixeis. A correlação entre aquelas variáveis mostrou-se ser muito baixa para
qualquer um dos crivos utilizados. No entanto, a relação entre o coeficiente de porosidade
na secção não-tangencial e a área média dos poros na secção tangencial foi a que
apresentou os melhores valores de R2. Também foi criado um algoritmo que pretende
quantificar a qualidade da cortiça em termos do coeficiente de porosidade, área média dos
poros e frequência dos poros
Study of soils from two trenches opened in a slope of the Serra do Mar for the sliding analysis
The landslides are mass gravitational movements induced by gravitational force and by the action of water. This event is the most recurrent and the largest producer of damages in Brazil. The objective of this research was to characterize soils from two trenches opened in a slope ot the Serra do Mar susceptible to landslides. Soil samples were collected and submitted to the geotechnical and physicoqchemical tests, which followed the Brazilian standards. A micro aggregation of the soil from both trenches was found on the basis of the granulometry analysis performed with and without deflocculant26XXVI Congresso de Iniciação Científica Unicam
Desiccation, storage and physiological quality of Phoenix roebelenii O’Brien (Arecaceae) seeds
Phoenix roebelenii is a palm species widely used in Brazil due to its exuberant leaves and adaptability to different climatic variations. For proper propagation, detailed information about seed viability, vigor and longevity subjected to dehydration and storage is yet to be obtained. For this purpose, the present research comprised two stages. The first one aimed at evaluating the response of seeds to desiccation and storage based on formal protocols. In the second stage, seeds were desiccated to 33, 30, 25, 23, 20, 18, 16, 12, 10 and 7% of water content by monitoring water loss in a convection oven at 35±2°C. After reaching each established water content, the seeds were subjected to germination tests. At 65 days after sowing, root length, root area, volume and diameter, shoot and eophyll length, and total seedling fresh and dry weights, were measured. Significant increases in germination and eophyll length were observed for lower seed water contents. Aversely, collar diameter decreased with seed desiccation.
Highlights:
Phoenix roebelenii seeds are orthodox.
Reduced seed water content increased the percentage of germination, the germination speed index, and eophyll length of Phoenix roebelenii seedlings.
Significant increases in germination and eophyll length were observed for lower seed water contents.
Aversely, collar diameter decreased with seed desiccation.Phoenix roebelenii is a palm species widely used in Brazil due to its exuberant leaves and adaptability to different climatic variations. For proper propagation, detailed information about seed viability, vigor and longevity subjected to dehydration and storage is yet to be obtained. For this purpose, the present research comprised two stages. The first one aimed at evaluating the response of seeds to desiccation and storage based on formal protocols. In the second stage, seeds were desiccated to 33, 30, 25, 23, 20, 18, 16, 12, 10 and 7% of water content by monitoring water loss in a convection oven at 35±2°C. After reaching each established water content, the seeds were subjected to germination tests. At 65 days after sowing, root length, root area, volume and diameter, shoot and eophyll length, and total seedling fresh and dry weights, were measured. Significant increases in germination and eophyll length were observed for lower seed water contents. Aversely, collar diameter decreased with seed desiccation.
Highlights:
Phoenix roebelenii seeds are orthodox.
Reduced seed water content increased the percentage of germination, the germination speed index, and eophyll length of Phoenix roebelenii seedlings.
Significant increases in germination and eophyll length were observed for lower seed water contents.
Aversely, collar diameter decreased with seed desiccation
Pós-Café: um sistema de apoio a decisão para o cálculo do custo da pós-colheita do café
Various computer programs were developed to calculate the cost of the coffee harvest. However, few address the costs of coffee in its post-harvest stage. This study was aimed to develop a system for calculating the cost of the coffee postharvest to facilitate decision making regarding the most cost-effective post-harvest processes. Thirty-four farmers in southern Minas Gerais state answered a questionnaire designed to validate this system. The use of a decision support system showed that the simulated costs in the post-harvest stage were not statistically different from the costs informed by the representatives of the selected farms.Vários programas computacionais foram desenvolvidos para calcular o custo da colheita do café. No entanto, poucos abordam os custos da fase de pós-colheita do café. Objetivou-se, neste trabalho, desenvolver um sistema de cálculo do custo da pós-colheita do café para facilitar a tomada de decisão quanto aos processamentos de melhor custo-benefício. Trinta e quatro fazendas do sul de Minas Gerais responderam a um questionário elaborado para validar esse sistema. Ao empregar o sistema de apoio à decisão, foi constatado que os custos simulados na fase de pós-colheita não diferem estatisticamente dos custos informados pelos responsáveis das fazendas entrevistadas
AGRONOMIC PERFORMANCE OF CHIA UNDER DIFFERENT SPATIAL ARRANGEMENTS
The nutritional benefits and functional potential of chia seeds have been highlighted in the literature. However, few studies address the planting system of the species, especially its spatial arrangement. Thus, this study proposes to evaluate chia cultivation under different spatial arrangements, aiming at its agronomic performance. The experimental design was randomized in blocks in a 3×2 factorial scheme, with three inter-row spacings (0.30, 0.45, and 0.60 m), two plant densities per linear meter (7.5 and 15 plants m−1), and four replications. Plant height, stem diameter, leaf area index, dry matter, chlorophyll index, leaf nitrogen content, panicle size, harvest index, and yield were evaluated. The evaluated spatial arrangements did not influence plant height, stem diameter, dry matter, leaf nitrogen content, panicle size, and harvest index. However, the spatial arrangement with the narrowest spacing and the highest population density was more suitable for obtaining a higher leaf area index and yield, with values of 5.96 and 2,507.44 kg ha−1, respectively. Therefore, a higher leaf area index and chia seed yield are obtained with an inter-row of 0.30 m and a population density of 15 plants m−1, that is, 500 thousand plants ha−1.Na literatura são destacados os benefícios nutricionais e o potencial funcional das sementes de chia, entretanto, ainda são poucos os trabalhos que abordam o sistema de plantio, em especial o arranjo espacial. Dessa forma, propôs-se no presente trabalho avaliar o cultivo da chia em diferentes arranjos espaciais, visando o seu desempenho agronômico. O delineamento experimental foi em blocos ao acaso, em esquema fatorial 3x2, sendo três espaçamentos entre linhas (0,30, 0,45 e 0,60 m) e duas densidades de plantas por metro linear (7,5 e 15 plantas m-1) com quatro repetições. Foram avaliadas altura de planta, diâmetro de caule, índice de área foliar, matéria seca, índice de clorofila, teor de nitrogênio foliar, tamanho da panícula, índice de colheita e produtividade. Os arranjos espaciais avaliados não influenciam a altura de plantas, diâmetro do caule, matéria seca, teor de nitrogênio foliar, tamanho da panícula e índice de colheita, sendo que o arranjo espacial composto pelo espaçamento mais estreito e a maior densidade populacional mostrou-se mais adequado para obtenção de índice de área foliar e produtividade mais elevados, nos valores de 5,96 e 2.507,44 kg ha-1, respectivamente. Concluiu-se que para obter maior índice de área foliar e produtividade de grãos de chia, a semeadura deve ser feita no espaçamento entre linhas de 0,30 m com densidade populacional de 15 plantas m-1, ou seja, 500 mil plantas ha-1
Alterações no perfil proteômico e de poliaminas induzido pelo envelhecimento de sementes de Cariniana legalis (Martius) O. Kuntze
Studies on metabolic processes and seed germinability of native endangered species are essential for its conservation. The objective of this work was to evaluate the effect of accelerated aging on germination and on the proteomic and polyamine (PAs) profile in seeds of Cariniana legalis. The seeds were aged at 41, 43, 45 and 47ºC for 24, 48, 72 and 96 h, under 100 % relative humidity using a completely randomized factorial design. The data were submitted to analysis of variance followed by Tukey’s test. The temperature of 47ºC was efficient in simulating seed aging, with no germination after 72 h of incubation. At 41ºC, the germination did not change significantly until 96 h. The reduction in the concentration of total free PAs, mainly spermidine, and the down-accumulation of heat shock proteins in seeds aged at 47°C were associated with induction of seed aging. Furthermore, the down-accumulation of the aconitate hydratase protein and the up-accumulation of the alcohol dehydrogenase protein were associated with loss of seed germinability and rapid deterioration in seeds aged at 47°C. The aging of C. legalis seeds is related to alteration in the contents of PAs and accumulation of some proteins involved with the loss of germinability.Estudos sobre processos metabólicos e germinabilidade de sementes de espécies nativas ameaçadas de extinção são essenciais para sua conservação. O objetivo deste trabalho foi avaliar o efeito do envelhecimento acelerado na germinação e no perfil proteômico e de poliamina (PAs) em sementes de Cariniana legalis. As sementes foram envelhecidas a 41, 43, 45 e 47°C por 24, 48, 72 e 96 h, sob 100% de umidade relativa, usando um delineamento fatorial inteiramente casualizado. Os dados foram submetidos à análise de variância seguida de teste Tukey. A temperatura de 47°C foi eficiente em simular o envelhecimento das sementes, que não germinaram após 72 h de incubação. Em 41°C, a germinação não mudou significativamente até 96h. A redução na concentração de PAs livres totais, principalmente espermidina e a diminuição no acúmulo de proteínas de choque térmico em sementes envelhecidas à 47°C foram associados à indução do envelhecimento das sementes. Além disso, a diminuição no acúmulo da proteína aconitato hidratase e o aumento no acúmulo da proteína álcool desidrogenase foram associados à perda de germinabilidade das sementes e rápida deterioração em sementes envelhecidas à 47°C. O envelhecimento de sementes de C. legalis está relacionado à alteração no conteúdo de PAs e a alteração de acúmulo de algumas proteínas envolvidas na perda da germinabilidade
Faixa de suficiência foliar, primeira aproximação para solo e diagnose nutricional do cafeeiro conilon orgânico
The objective of this study was to establish the Sufficiency Range Approach of both the Foliar (SRAF) and the soil nutrient contents (SRAS) of Conilon coffee trees (Coffea canephora Pierre ex Froehn), cultivated organically in Espírito Santo - Brazil. The nutritional diagnosis using Diagnosis Recommendation Integrated System (DRIS) 1and SRAF, was also compared. The nutrient contents of the leaves and soil were evaluated in 56 organic crops. To establish SRAF and SRAS, the foliar and the soil nutrient contents was used respectively, from 22 crops with high yield (equal or above 2,400 kg ha-1 coffee fruit processing). The comparison between DRIS and SRAF was performed through the ordination of the limiting nutrients and qui-square test. Results revealed that SRAF was of: N (g kg-1) 26.2-29.0, P (g kg-1) 1.51-1.75, K (g kg-1) 14.7-18.7, Ca (g kg-1) 12.4-14.6, Mg (g kg-1) 2.92-4.19- 6, S (g kg-1) 1.85-2.33, B (mg kg-1) 45.5-63.5, Cu (mg kg-1) 11.1-21.1, Fe (mg kg-1) 69.2-155.0, Mn (mg kg-1) 49.6-98.2 and Zn (mg kg- 1) 7.83-9.97. The SRAS was of: P (mg dm-3) 4.67-15.27, K (mg dm-3) 62.7-258.00, Ca (cmolc dm-3) 1.65-3.49, Mg (cmolc dm-3) 0.61- 0.99, S (mg dm-3) 6.94-27.2, B (mg dm-3) 0.43-0.61, Cu (mg dm-3) 0.15-0.43, Fe (mg dm-3) 31.05-100.20, Mn (mg dm-3) 8.78-56.60 and Zn (mg dm-3) 2.35-6.51. In several cases SRAF identified limitations in the organic Conilon coffee productivity that were not identified by DRIS. DRIS indicated limitation when the nutrient was inside of the SRAF. Manganese followed by P, Cu=Fe and N were the nutrients considered as deficient to the yield, when DRIS was used, on the other hand, when the SRAF was used Mn, Ca, Fe and N were considered deficient nutrients.Faltam valores de referência de folha e solo, e diagnóstico nutricional de lavouras de café Conilon orgânico, cultivadas no Espírito Santo, assim, objetivou-se com este trabalho propor faixa de suficiência foliar (FSF) e uma primeira aproximação de teores químicos no solo, para cafeeiro Conilon (Coffea canephora Pierre ex Froehn) cultivado de forma orgânica no Espírito Santo Brasil e, bem como realizar e comparar diagnóstico nutricional utilizando o DRIS e FSF. Determinaram-se as concentrações de nutrientes nas folhas e no solo de 56 lavouras orgânicas. Estabeleceu-se a FSF e a primeira aproximação utilizando concentrações foliares e do solo de 22 lavouras com alta produtividade (igual ou superior a 2.400kg ha-1 de café beneficiado). Para comparar o DRIS e FSF, os nutrientes limitantes foram quantificados e ordenados por meio do teste qui-quadrado. A FSF foi: em g kg-1 N 26,2- 29,0, P 1,51-1,75, K 14, 7-18,7, Ca 12,4-14,6, Mg 2,92-4,19-6 e S 1,85-2,33 e em mg kg-1 B 45,5-63,5, Cu 11,1-21,1, Fe 69,2-155,0, Mn 49,6-98,2 e Zn 7,83-9,97. A primeira aproximação foi: em mg dm-3 P 4,67-15,27, K 62,7-258,0, S 6,94-27,2, B 0,43-0,61, Cu 0,15- 0,43, Fe 31,05-100,2, Mn 8,78-56,60 e Zn 2,35-6,51 e, em cmolc dm-3 Ca 1,65-3,49 e Mg 0,61-0,99. Os resultados indicaram que a faixa crítica apontou limitação da produção em várias situações em que o DRIS não identificou. O DRIS indicou limitação quando o nutriente estava dentro da faixa crítica. O Mn seguido pelo P, Cu=Fe e N foram os nutrientes que se destacaram como limitantes da produção ao utilizar o DRIS. Ao considerar a faixa crítica o Mn, Ca, Fe e N foram considerados limitantes
Desenvolvimento de cenários utilizando um sistema de apoio à decisão para análise de custos da fase de pós-colheita do café
The choice of method of processing coffee is decisive on the profitability of the coffee activity, and will depend on several factors. Thus, due to the existence of many variables is common producer ask about the viability of certain types of processing. Thus, the objective of this study was to detail the proposed processing alternative to two farms more profitable. Forty-six farms in the regions of the Cerrado, Matas de Minas and southern of Minas Gerais state answered a questionnaire in order to enable this analysis. By employing the decision support system for the calculation of the coffee postharvest cost , it was found that 21 farms with original dry processing gain between R 35.9039 per bag of coffee produced if they chose the alternative wet processing . As for the 25 farms with original wet processing lose from R 7.26029 per bag of coffee produced, if they chose the alternative splicing via dry.A escolha do modo de processamento do café é decisiva na rentabilidade da atividade cafeeira, e dependerá de diversos fatores. Assim, em decorrência da existência de tantas variáveis é comum produtor questionar a viabilidade de determinados tipos de processamentos.Objetivou-se, neste trabalho, detalhar a proposta de processamentos alternativos mais rentáveis para duas fazendas. Quarenta e seis fazendas das regiões do Cerrado, Matas de Minas e Sul de Minas Gerais responderam a um questionário elaborado no sentido possibilitar esta análise. Ao empregar o sistema de apoio à decisão para o cálculo do custo da pós-colheita do café, ficou constatado que as 21 fazendas, com processamento original via seca, ganhariam entre R 35,9039 por saca de café produzido, caso optassem pelo processamento alternativo via úmida. Já as 25 fazendas com processamento original via úmida perderiam entre R 7,26029 por saca de café produzido, caso optassem pelo processamento alternativo via seca
Growth and yield of Syagrus schizophylla (Mart.) Glass. in response to light gradients
This research studied growth and yield of Syagrus schizophylla, an extinction-endangered ornamental palm, grown under five light gradients. The treatments were: G1 - PAR=1234.10 μmol photons m-2 s-1, G2 - PAR=913.16 μmol photons m-2 s-1, G3 - PAR=666.34 μmol photons m-2 s-1, G4 - PAR=419.56 μmol photons m-2 s-1 and G5 - PAR=534.77 μmol photons m-2s-1. Before the experiment and at three, five and seven months of treatment, growth (plant height, collar diameter, number of leaves, petiole length, leaf length and width), gas exchange, chlorophyll a, and leaf green color intensity were assessed. The highest net photosynthetic rates were observed in plants under G2, G3 and G4. Values of maximum quantum efficiency (Fv/Fm) over 0.75 were observed under G2. At seven months, estimated SPAD values were 36 in G2 plants and 32 in G1 plants. According to the Dickson quality index (DQI), presented the highest growth and development rates. We conclude that G2 suits plants to be transplanted into the field, whereas G3 would be best for plants grown under shade environments.
Highlights:
Syagrus schizophylla is an extinction endangered ornamental palm.
One layer of Red Chromatinet® 50% should be recommended for the first year of growth of schizophylla plants to be later transplanted to the field.
Two Red Chromatinet® 50% layers would be best for plants meant to grow under shade environments.
The highest net photosynthetic rates were observed in plants under G2, G3 and G4.This research studied growth and yield of Syagrus schizophylla, an extinction-endangered ornamental palm, grown under five light gradients. The treatments were: G1 - PAR=1234.10 μmol photons m-2 s-1, G2 - PAR=913.16 μmol photons m-2 s-1, G3 - PAR=666.34 μmol photons m-2 s-1, G4 - PAR=419.56 μmol photons m-2 s-1 and G5 - PAR=534.77 μmol photons m-2s-1. Before the experiment and at three, five and seven months of treatment, growth (plant height, collar diameter, number of leaves, petiole length, leaf length and width), gas exchange, chlorophyll a, and leaf green color intensity were assessed. The highest net photosynthetic rates were observed in plants under G2, G3 and G4. Values of maximum quantum efficiency (Fv/Fm) over 0.75 were observed under G2. At seven months, estimated SPAD values were 36 in G2 plants and 32 in G1 plants. According to the Dickson quality index (DQI), presented the highest growth and development rates. We conclude that G2 suits plants to be transplanted into the field, whereas G3 would be best for plants grown under shade environments.
Highlights:
Syagrus schizophylla is an extinction endangered ornamental palm.
One layer of Red Chromatinet® 50% should be recommended for the first year of growth of schizophylla plants to be later transplanted to the field.
Two Red Chromatinet® 50% layers would be best for plants meant to grow under shade environments.
The highest net photosynthetic rates were observed in plants under G2, G3 and G4
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