133 research outputs found
Incidence of grapevine leafroll associated viruses -1, -2, and -3 in Mendoza vineyards
Indexación: ScieloViticulture is important in Argentina's economy, especially in the province of Mendoza,
which is responsible for more than 75% of the crop cultivated area. In this work, we evaluated the
incidence of Grapevine leafroll-associated viruses (GLRaV) -1, -2, and -3 in Vitis vinifera clones of
cultivars Cabernet Sauvignon, Cabernet Franc, and Sauvignon Blanc, planted in different zones of
Mendoza. The selected clones were previously reported as putatively infected by GLRaV-2. All selected
samples were analyzed by DAS-ELISA for GLRaV-1,-2 and -3. GLRaV-2 was the only virus identified in
all the analyzed clones. The overall infection rates were 0.6%, 18.8% and 1.2 % for GLRaV-1, 2 and 3
respectively. For the clone Cabernet Sauvignon 337, the infection rate was very high (68.3%).http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1982-56762010000600007&nrm=is
Influencia de la concentración de sacarosa en el medio, sobre la respuesta de material de vid "in vitro"
7 páginas, 8 figuras y 16 referencias.-- Trabajo presentado en el VI Simposium Nacional - II Ibérico sobre nutrición mineral de las plantas, Sevilla, del 12 al 15 de Noviembre de 1996.-- Entidades colaboradoras Junta de Andalucía, Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Sociedad Española de Fisiología Vegetal, El Monte, Caja de Huelva y Sevilla y Gat Fertilíquido. Editores científicos: Rafael Sarmiento Solís, Eduardo O. Leidi Montes y Antonio Troncoso de Arce.-- (Instituto de Recursos Naturales y Agrobiología de Sevilla).[EN]: The effects of two sucrose amounts, 20 and 30 gl(elevado a -1), added to the nutrient medium on the in vitro development of grapevine rootstocks 4 lB, 110 Richter, 196-17, 161-49 de Couderc and Rupestris de Lot, of Superior cultivar and of CH-I ,and CH-2 clones from Chile was studied.
Medium with the lowest amount of sucrose favoured the aerial part growth of varieties ) 61-49,
Rupestris de Lot, Superior and 196-17. This major growth of aerial part of explant (organs with
clhorophyll), did not produce it in radical system. Development of this system was independent of sugar concentration in substrat and more in relation with grape variety Substrat with 20 gl(elevado a -1) of sucrose also shown a light major inclination to vitrification of in vitro plant.
material[ES]: Se estudia el efecto de dos concentraciones (20 y 30 gl(elevado a -1)) de sacarosa en el medio de cultivo, sobre el desarrollo in vitro de los portainjertos de vid 41B, 110 de ichter,) 96-17, 161-49 de Couderc y Rupestris de Lot, del cultivar Superior y de los clones CH-) y CH-2 procedentes de Chile.
El medio con la concentración mas baja de sacarosa favoreció, en general el crecimiento de la parte aérea del material de vid in vitro, en especial de las variedades 161-49, Rupestris de Lot, Superior y 196-17. Este mayor crecimiento de la parte aérea del explanto (órganos con clorofila), no se produjo en el sistema radical, cuyo desarrollo fue independiente de la concentración de azúcar en el medio y mas relacionable con la variedad de vid.
El medio con 20 gl(elevado a -1) de sacarosa también mostró una ligera mayor predisposición a.la vitrificacón del material vegetal in vitro.Peer reviewe
An integral formulation for wave propagation on weakly non-uniform potential flows
An integral formulation for acoustic radiation in moving flows is presented.
It is based on a potential formulation for acoustic radiation on weakly
non-uniform subsonic mean flows. This work is motivated by the absence of
suitable kernels for wave propagation on non-uniform flow. The integral
solution is formulated using a Green's function obtained by combining the
Taylor and Lorentz transformations. Although most conventional approaches based
on either transform solve the Helmholtz problem in a transformed domain, the
current Green's function and associated integral equation are derived in the
physical space. A dimensional error analysis is developed to identify the
limitations of the current formulation. Numerical applications are performed to
assess the accuracy of the integral solution. It is tested as a means of
extrapolating a numerical solution available on the outer boundary of a domain
to the far field, and as a means of solving scattering problems by rigid
surfaces in non-uniform flows. The results show that the error associated with
the physical model deteriorates with increasing frequency and mean flow Mach
number. However, the error is generated only in the domain where mean flow
non-uniformities are significant and is constant in regions where the flow is
uniform
Incidência do Grapevine Leafroll Associated Viruses -1, -2, e -3 em vinhedos de Mendoza
Indexación: Web of Science; ScieloViticulture is important in Argentina's economy, especially in the province of Mendoza, which is responsible for more than 75% of the crop cultivated area. In this work, we evaluated the incidence of Grapevine leafroll-associated viruses (GLRaV) -1, -2, and -3 in Vitis vinifera clones of cultivars Cabernet Sauvignon, Cabernet Franc, and Sauvignon Blanc, planted in different zones of Mendoza. The selected clones were previously reported as putatively infected by GLRaV-2. All selected samples were analyzed by DAS-ELISA for GLRaV-1,-2 and -3. GLRaV-2 was the only virus identified in all the analyzed clones. The overall infection rates were 0.6%, 18.8% and 1.2 % for GLRaV-1, 2 and 3 respectively. For the clone Cabernet Sauvignon 337, the infection rate was very high (68.3%).A viticultura é importante para a economia da Argentina, especialmente na província de Mendoza, que abrange mais de 75% da área cultivada do país. Neste trabalho, nós avaliamos a incidência de Grapevine leafroll associated virus (GLRaV) -1, -2 e -3 em clones de Vitis vinifera das cultivares Cabernet Sauvignon, Cabernet Franc e Sauvignon Blanc, cultivadas em diferentes zonas de Mendoza. Os clones selecionados foram previamente relatados como provavelmente infectados por GLRaV-2. Todas as amostras selecionadas foram analisadas por DAS-ELISA para GLRaV-1, -2 e -3. GLRaV-2 foi o único vírus identificado em todos os clones analisados. As incidëncias das infecçoes globais foram 0,6%, 18,8% e 1,2% para GLRaV-1, 2 e 3, respectivamente. No Cabernet Sauvignon clone 337 a incidëncia da infecção foi muito elevado (68,3%).http://ref.scielo.org/4br9s
Pruning the apple
Caption title.Original in the University of Missouri--Columbia Libraries collections; scanned by the University of Missouri Systems Office
Evaluation of grapevine water status from trunk diameter variations
We evaluated the usefulness of short-term trunk diameter variations (TDV) as water stress indicator in field-grown grapevines cv. Tempranillo. Two indices were calculated from TDV, maximum daily trunk shrinkage (MDS), and trunk growth rate (TGR). The seasonal evolution of both indicators was compared with occasional determinations of pre-dawn leaf water potential and stem water potential, measured at early morning (Ψ s em ) and at midday (Ψ s md ) in irrigated and non-irrigated vines. In the second season, the effect of crop load on the vine water status indicators was also studied. Crop load did not affect either the vine water relations or the TDV. All water potential determinations had much lower variability and were more sensitive than both MDS and TGR to water restrictions. The ability of both indices to detect plant water stress varied largely depending upon the phenological period. In fact, MDS and TGR were only able to detect vine water stress during a short period of time before veraison. During this period, TGR was linearly related to both Ψ s em and Ψ s md , while for MDS a curvilinear, quadratic equation, better described the relationship with plant water status. After veraison no apparent relationship existed between plant water status and MDS or TGR. Hence, our results question the practical use of both MDS and TGR as variables to automate irrigation scheduling for grapevin
Growth, physiology and yield of durum wheat (Triticum durum) treated with sewage sludge under water stress conditions
In arid and semi-arid areas, low soil fertility and water deficit considerably limit crop production. The use of sewage sludge as an organic amendment could contribute to the improvement of soil fertility and hence the agronomic production. The study aims to highlight the behaviour of durum wheat to the application of sewage sludge associated with water stress. The assessment focused on morphophysiological parameters of the wheat plant and yield. Under greenhouse conditions, the variety Mohamed Ben Bachir was treated by four water stress levels (100 %, 80 %, 50 % and 30 %). Each stress level comprised five fertilizer treatments: 20, 50 and 100 t/ha of dry sludge, 35 kg/ha of urea, and a control with no fertilization. Results revealed a significant loss in water content and chlorophyll a in leaves. Water stress negatively affected the development of wheat plants by reducing significantly seed yield, leaf area and biomass produced. Plant’s responses to water stress manifested by an accumulation of proline and a decrease in total phosphorus. However, the increasing doses of sewage sludge limited the effect of water stress. Our findings showed an increase in the amount of chlorophyll pigments, leaf area, total phosphorus, biomass and yield. In addition, excessive accumulation of proline (1.11 ± 1.03 μg/g DM) was recorded as a result of the high concentration of sludge (100 t/ha DM). The application of sewage sludge is beneficial for the wheat crop, but the high accumulation of proline in plants treated with high dose of sludge suggests to properly consider this fact. The application of sludge should be used with caution in soils where water is limited. Because the combined effect of these two factors could result in a fatal osmotic stress to crop development
First studies on the potential of a copper formulation for the control of leaf stripe disease within esca complex in grapevine.
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