668 research outputs found
NEW DYAD FROM RENEWABLE SOURCE FOR APPLICATIONIN ORGANIC SOLARCELLS
This work was supported by the Araucária Foundation, a Research Founding Agency from Paraná State – Brazil, CAPES and CNPq
Ecophysiological potential of the Dão terroir for the production of Touriga Nacional red grapes
Proceedings - IX International Terroir Congress, 2012Aiming to evaluate the potential of the portuguese Dão winegrowing region for the production of Touriga Nacional
(TN) red grapes, climatic, ecophysiological and viticultural data from two different climatic years (2004, wet year and
2005, dry year) are presented and discussed. The data was collected in the control non-irrigated plants of an irrigation
experiment installed at the Dão Research Station, Nelas, Portugal. The vineyard is established in a typical granitic soil
and trained on a vertical shoot positioning. According to the Géoviticulture Multicriteria Climatic Classification
System, the Dão region is classified as temperate/temperate warm for the heliothermal index, with cool nights (night
cold index) and moderately dry (dryness index). In 2004 the predawn leaf water potential presented always values
higher than -0.2 MPa from flowering to harvest but in 2005 moderate to severe water stress was observed during the
ripening period (-0.4 MPa at veraison to -0.6 MPa at harvest). Leaf stomatal conductance and photosynthetic rate
displayed a decreasing pattern from flowering to harvest in both years but attained much lower values in the 2005
ripening period as compared to that of 2004. The yield was similar in both years but 2005 showed lower sugar content,
similar titratable acidity and a higher anthocyanin berry skin content. Our data shows that the Dão terroir presents a
high inter-annual climate variability which has important repercussions on TN responses being the most unfavorable
climatic years those were the high temperatures are coincident with water stress during the first half of the ripening
period. In those years irrigation should be applied in order to obtain better quality grapes
Response of growth, yield and berry composition to basal leaf removal in Jaen grapevine
Results from a leaf removal experiment located at Dão Winegrowing region of Portugal are presented.
Three intensity levels of defoliation (control non-defoliated, leaves removed up to the third basal node and up to
the sixth basal node) are compared. Defoliation treatments had no significant effect on yield and on must soluble
solids, showing that the remaining leaves were able to guarantee berry development and sugar accumulation in
the fruit. The more intense defoliation treatment induced favorable effects on light microclimate in the cluster
zone, with positive consequences for polyphenols synthesis and reduction of Botrytis cinerea Pers. incidenceinfo:eu-repo/semantics/publishedVersio
Effect of vineyard floor management practices on water use: A case study at a terroir of the "Dão" winegrowing region in Portugal
Aiming to evaluate the effect of vineyard floor management practices on water use and vine performance, a field
experiment was carried out at the Dão Wine Research Station, located at Nelas, Center Portugal. The experiment
was set up in 2010 in a mature vineyard planted with the red grape variety ‘Touriga Nacional’, using a 2x2 factorial
design with the following treatments: inter-row soil management (permanent resident vegetation vs. soil
tillage) and undervine floor management (mulch vs. herbicide). In this paper it will be presented data from 2013
growing season (four seasons after experiment setup). The volumetric soil moisture, assessed with a capacitance
probe to a 1.5 m depth, showed a decreasing pattern throughout the growing season in all treatments with the
resident vegetation presenting lower values as compared to the tillage treatment, while no significant differences
were observed between the two undervine floor management practices. From budburst to flowering the resident
vegetation treatment showed a higher soil water depletion (up to 1.5 m depth) than the tillage treatment but the
relative situation was reversed during the flowering-veraison period, while no significant differences were observed
during the ripening period. Vine stem water potential values showed a decreasing pattern along the season
attaining very low values during September but with no significant differences between treatments. In general
the soil management practices did not significantly affect vine vigor, yield and berry composition however, since
these results are only from one season, further data analysis in ongoing in order to allow stronger conclusions.info:eu-repo/semantics/publishedVersio
Effects of irrigation on the vigour, yield and berry composition of the red variety Touriga Nacional at the Dão winegrowing region, Portugal
Proceedings - 17 th International Symposium GIESCO, Asti, Italy, 2011In a field trial installed at the Centro de Estudos Vitivinícolas do
Dão, Nelas, Portugal, the effect of three irrigation treatments on
the agronomic behaviour of cv Touriga Nacional (Vitis vinifera L.)
were studied during three growing seasons (2006-2008). Three
irrigation treatments (DI30 - irrigation with 30% of ETc; DI50 -
irrigation with 50% ETc, FI - full irrigation – 100% Etc) were
compared to a control non-irrigated treatment (NI). Compared to
NI, the deficit irrigation treatments (DI30 & DI50) showed no
significant differences on the yield and its components. The full
irrigation treatment induced a significantly higher yield due to a
higher bunch weight, as compared with the others treatments.
Compared to the control, the deficit irrigation treatments presented
similar berry composition during all the three seasons. The FI
treatment presented, in all seasons, a significantly higher total
acidity and a significantly lower Brix and total anthocyanins
concentration as compared to the other treatments. The pruning
weight and shoot weight increased with the amount of irrigation
water applied, but significant differences were found only between
the FI and the NI treatments, the last presenting the lowest values.
Despite the fact that in the non-irrigated vineyards of the Dão
winegrowing region it is very common to observe vine water
stress symptoms, mainly during the ripening period, during the
three studied seasons (2006-2008), the deficit irrigation treatments
showed no advantages relatively to the control non-irrigated.
Despite the higher yield produced in the full irrigation, this
treatment had the disadvantages of the excessive vine vigour and
lower must quality produced
Daily evolution of the components of the balance of radiation of vines in a vineyard in the Dão region
Proceedings - 17 th International Symposium GIESCO, Asti, Italy, 2011In order to validate a model of vine transpiration based on
radiative surface temperature a field trial was conducted in a
vineyard in the Dão region, centre of Portugal, with the cultivar
“Touriga Nacional”. The model is based on the partition of net
radiation between the components of the canopy (vines, soil, and
grass cover), considering that the vines and the undercover (soil
plus grass cover) act separately and in parallel. Thus, the latent
heat flux from the vines to the atmosphere (lTc) is determined
from vine net radiation (Rnc) and sensible heat flux (Hc). The
partition of net radiation (Rn) between the undercover (Rns) and
the vines (Rnc) is made considering the exponential form for
radiation extinction, with the coefficient of extinction being
corrected with a factor dependent on the zenital solar angle (j)
while leaf area index (LAI) is corrected with a clumping factor,
Ω(φ). Sensible heat flux from the vines (Hc) is calculated from
radiative temperature (Tc) considering that the fluxes from the
different origins are independent and that there are two resistances
in series between the canopy and the atmosphere: the leaf
boundary layer resistance (raHc) and the aerodynamic resistance of
the crop (raH). Besides the estimation of the daily values of
transpiration, the model allows to study the evolution of the
different components of the radiation balance throughout the day.
The daily evolution of the evaporation fraction from the vines
(FEc) can be approximated by a concave curve. Values of FEc > 1
show that, under certain circumstances and periods of the day,
energy used for transpiration (lTc) is greater than crop net
radiation, which indicates that there are exchanges of energy
between the several components of the surface, namely when
evaporative demand from the atmosphere is high and there are no
soil water restrictions. The model also shows that, regardless of the
soil water status, transpiration is a big part of Rn when these values
are low (in the beginning of the morning and late afternoon)
PHOTOCATALYTIC ACTIVITY OF GRAPHENE OXIDE/ZnO COMPOSITES FOR DYE DEGRADATION
This work was supported by the Araucária Foundation, a Research Founding Agency from Paraná State - Brazi
Monda de cachos na casta ´Touriga Nacional´, região do Dão
Num ensaio instalado na Quinta da Cale, Nelas, durante dois anos consecutivos (2004-2005) foram comparadas duas intensidades de monda ao pintor - M30 (monda de 30% cachos) e M50 (monda de 50% cachos), com uma testemunha não mondada. Foram analisados o rendimento e seus componentes, os parâmetros de qualidade das uvas e calculado o retorno financeiro da produção com e sem a realização da monda. Os vinhos resultantes do ciclo de 2005 foram sujeitos a prova organoléptica. Comparativamente à testemunha não mondada, a monda não provocou alterações significativas na fertilidade, abrolhamento e vigor mas induziu uma redução da produção de 37% (M30) e 52% (M50) em 2004 e de 36% (M30) e 20% (M50) em 2005. Com excepção do grau álcool provável do mosto, a monda de cachos não induziu alterações significativas quer na composição do mosto quer nas características organolépticas dos vinhosinfo:eu-repo/semantics/publishedVersio
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