5,456 research outputs found
Efeito do zinco, boro, molibdênio e calagem na produção de soja-perene (Glycine javanica L.) cultivada em solos de cerrado, em condições de casa-de-vegetação.
Este trabalho foi conduzido em casa-de-vegetacao, com amostras de solos do municipio de Sete Lagoas, Estado de Minas Gerais. Foram coletadas amostras de solo: Latossolo Vermelho-Amarelo e Latossolo Vermelho-Escuro, fase cerrado, de 0 a 20 cm de profundidade. Este trabalho teve como objetivo estudar a resposta da soja-perene (Glycine javanica L.) variedade "Tinaroo", a aplicacao de zinco, boro molibdenio e calagem bem como observar a influencia da calagem na disponibilidade de alguns nutrientes. As plantas foram analisadas quanto aos testes totais de nitrogenio, fosforo, potassio, calcio, magnesio, zinco, boro e molibdenio
Cork oak (Quercus suber L.) seedlings acclimate to elevated
Leaf gas-exchange, leaf and shoot anatomy,
wood density and hydraulic conductivity were investigated in
seedlings of Quercus suber L. grown for 15 months either at
elevated (700 lmol mol-1) or normal (350 lmol mol-1)
ambient atmospheric CO2 concentrations. Plants were
grown in greenhouses in a controlled environment: relative
humidity 50% (±5), temperature similar to external temperature
and natural light conditions. Plants were supplied
with nutrients and two water regimes (WW, well watered;
WS, water stress). After 6 months exposure to CO2
enrichment an increase in photosynthetic rate, a decrease in
stomatal conductance and a decrease in carbon isotope
discrimination (D13C) were observed, along with enhanced
growth and an increase in the number of branches and
branch diameter. Over the same period, the shoot weight
ratio increased, the root weight ratio decreased and the leaf
weight ratio was unaffected. The specific leaf area increased
due to an increase in total leaf thickness, mainly due to the
palisade parenchyma and starch. However, after 9 and
15 months of elevated CO2 exposure, the above-mentioned
physiological and morphological parameters appeared to be
unaffected. Elevated CO2 did not promote changes in vessel
lumen diameter, vessel frequency or wood density in stems
grown in greenhouse conditions. As a consequence, xylem
hydraulic efficiency remained unchanged. Likewise, xylem
vulnerability to embolism was not modified by elevated
CO2. In summary, elevated CO2 had no positive effect on
the ecophysiological parameters or growth of water stressed
plants
The decay of homogeneous anisotropic turbulence
We present the results of a numerical investigation of three-dimensional
decaying turbulence with statistically homogeneous and anisotropic initial
conditions. We show that at large times, in the inertial range of scales: (i)
isotropic velocity fluctuations decay self-similarly at an algebraic rate which
can be obtained by dimensional arguments; (ii) the ratio of anisotropic to
isotropic fluctuations of a given intensity falls off in time as a power law,
with an exponent approximately independent of the strength of the fluctuation;
(iii) the decay of anisotropic fluctuations is not self-similar, their
statistics becoming more and more intermittent as time elapses. We also
investigate the early stages of the decay. The different short-time behavior
observed in two experiments differing by the phase organization of their
initial conditions gives a new hunch on the degree of universality of
small-scale turbulence statistics, i.e. its independence of the conditions at
large scales.Comment: 9 pages, 17 figure
Influência de nitrogênio, micronutrientes e matéria orgânica na produção de melão.
O trabalho constituiu-se de dois experimentos com a cultura do melão (Cucumis melo L.) conduzidos em um Latossolo Vermelho-Amarelo, de textura arenosa no Campo Experimental de Bebedouro, em Petrolina-PE e em um Vertissolo, no Campo Experimental de Mandacaru, em Juazeiro-BA, ambos pertencentes a Embrapa Semi-Árido
Caracterização química do óleo essencial de erva-cidreira, nas condições de Manaus, AM.
O objetivo do trabalho foi avaliar o teor e caracterização química do óleo essencial desta espécie nas condições de Manaus, AM.Suplemento. Edição dos Resumos do 52º Congresso Brasileiro de Olericultura, Salvador, jul. 2012
Sensory analysis as a tool to support rice breeding research: a comparison between hybrid rice and conventional commercial rice.
This study aims to assess sensory differences between a hybrid variety sample and conventional commercial rice samples by the Difference from Control Method. This method provides information on the size of the difference between a control and other sample
Índices espectrais, diagnóstico da vegetação e da degradação da caatinga da bacia do Rio Taperoá-PB.
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