45 research outputs found
Cytological aspects of compatible and incompatible interactions between cashew (Anacardium occidentale L.) seedlings and isolates of Colletotrichum gloeosporioides (Penz.) complex
A strategy in the control anthracnose of cashew (Anacardium occidentale L.) is the management of crop phenology and defense mechanisms of this host. In previous studies, under
controlled conditions, the seedling reactions of 5 cashew clones (CAP-14, CCP-06, CCP-09, CCP76 and CCP-1001) to 36 isolates of Colletorichum gloeosporioides Penz. complex (LARS- 905 to 940) was evaluated. However, good field management requires information about the infection process. This research aimed to clarify cytophysiological aspects of three compatible interactions of this pathosystem (isolates LARS-905 and 910 × CCP-76; LARS-910 × CCP-1001) and an incompatible one (LARS-905 × CCP-1001), using infected leaves/stems and microscopy (light, scanning and transmission electron). No significant differences were found prior to penetration. In the susceptible combinations, 36-66 h after inoculation, a thin primary hypha (TPH) formed in the invaded epidermal cell, widening as a large primary hypha (LPH), which filled the cell lumen simultaneously with accumulation of of yellow-brown lignopolysaccharides. Then, a thin secondary hypha (TSH) developed from the LPH, penetrating adjacent cells before the first became necrotic. In the incompatible interaction, the response of the first invaded cell was faster and more intense, with formation of papilla and lignopolysaccharide-protein-silicon complex usually blocking the pathogen
Spatial climate variability and viticulture in the Miño River Valley of Spain
Understanding spatial variations in climates that are crucial for crop suitability form the basis of zonation studies in viticulture. This research applies principal components analysis and cluster analysis to 39 climate stations in the Galician region of northwest Spain to examine the applicability for zonation in the region and produce a better understanding of the spatial climate structure in Galicia. Roughly 90 % of the spatial variation in climate types is explained by three main components, which are defined by precipitation, temperature, and frost risk variations across the region. The climate variables or indices most important for the Galician region include the three main indices (Huglin index, Dryness index, and Cool night index) used within the Multicriteria Climatic Classification System (Geoviticulture MCC System). The results provide evidence that the Geoviticulture MCC System, which was developed at the global scale, has tremendous applicability at the mesoscale. The identification of six climate types of the Geoviticulture MCC System, which are used quite extensively for wine growing in the region, depicts the great spatial diversity of viticultural potential found within the relatively small area of Galicia.
Influence of elevation and slope exposure on must volatiles of mencÃa cultivar from Ribeira Sacra (NW Spain)
Ribeira Sacra is a Spanish Denomination of Origen (D.O.) that produces young red wines from MencÃa cultivar (Galicia, NW). The orography of the Ribeira Sacra D.O. is very characteristic and renders a wide variety of situations that combine elevation,
orientation, slope exposure and slope inclination. Indeed, in this area all have terraced vineyards are very close to just one meter wide, where it is only a single row of vines and spread over the slopes which normally have a large inclination (70 to 80 ° slope).
With a south-southwest direction, the vineyards are protected from cold winds from the north and the sun bathes the terraces throughout the day. The stone warmed by the sun during the day blunted the lower night temperatures avoiding frost.
During the year 2009 we have studied the volatile composition of MencÃa cultivar in six different situations (orientation and altitude) of Amandi subzone (Ribeira Sacra D.O.)
and the relationship with the altitude and exposition. The results showed the influence climatic and topographic conditions on the volatile composition of MencÃa grape grown along Amandi site from Ribeira Sacra D.O. Six different situations were studied and the
data were analysed by analysis of variance and mean differences between situations were calculated using the LSD Fishers’ test. Biplot principal component analysis (PCA) was performed with mean of volatile compounds identified and quantified. The results
showed significant differences among the different situations studied, showed different ripening states in the vineyard
Influence of elevation and slope exposure on must volatiles of MencÃa cultivar from Ribeira Sacra (NW Spain)
Resumen del póster presentado al Congreso que bajo el lema "Science and horticulture for people" se celebró en Lisboa del 22 al 27 de Agosto de 2010.Peer reviewe
The tau weak-magnetic dipole moment
We calculate the prediction for the anomalous weak-magnetic form factor of
the tau lepton at within the Standard Model. With all particles
on-shell, this is a electroweak gauge invariant quantity. Its value is
. We show that the
transverse and normal components of the single-tau polarization of tau pairs
produced at unpolarized collisions are sensitive to the real and
absorptive parts of the anomalous weak-magnetic dipole moment of the tau. The
sensitivity one can achieve at LEP in the measurement of this dipole moment is
discussed.Comment: 16 pages, Latex, 2 figure
Recommended from our members
Effects of Dwarf Mistletoe on Stand Structure of Lodgepole Pine Forests 21-28 Years Post-Mountain Pine Beetle Epidemic in Central Oregon
Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum) also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21–28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its potential to influence stand structure
The Electroweak Chiral Lagrangian and CP-Violating Effects in Technicolor Theories
We estimate the CP-violating and anomalous form factors,
arising from CP-violating interactions in extended technicolor theories, and
discuss their future experimental detectability. The electric dipole moment of
the boson is found to be as large as {\cal O}(10^{-21}) \; \mbox{e cm}.
We connect the CP-odd and couplings to the corresponding
CP-violating electroweak chiral lagrangian operators. The electric dipole
moments of the neutron and the electron in technicolor theories are estimated
to be as large as {\cal O}(10^{-26}) \; \mbox{e cm} and {\cal O}(10^{-29})
\; \mbox{e cm} respectively. We also suggest the potential to observe large
CP-violating technicolor effects in the decay .Comment: 34 pages, YCTP-P9-94, LaTex. (minor changes in wording and notation,
the figures are appended at the end as one postscript file
Highly Divergent Mitochondrial ATP Synthase Complexes in Tetrahymena thermophila
Tetrahymena ATP synthase, an evolutionarily divergent protein complex, has a very unusual structure and protein composition including a unique Fo subunit a and at least 13 proteins with no orthologs outside of the ciliate lineage
Problemas de fertilidad en los suelos de viñedo de la D.O. Ribeira Sacra (Galicia, NO de España)
2 páginas.- Comunicación presentada al IV Congreso sobre uso y manejo del suelo (UMS) celebrado en Coruña (España) del 14 al 16 de Julio de 2010.Peer reviewe