1,720,994 research outputs found
European collaboration for the grapevine phenotypic diversity exploitation
No full textTrabajo presentado en la Final Conference Progress in Vitis Vinifera diversity evaluation and use, celebrada en Lisboa del 7 al 9 de octubre de 2014.-- Rustioni, Laura et al.Cost action FA1003 - GRAPENET. East-West Collaboration for Grapevine Diversity Exploration and Mobilization of Adaptive Traits for Breeding.Common limits for phenotyping are costs in terms of equipment, specialized
researchers, and time. Moreover, phenotyping requires specific methods in relation to the studied traits, and
each method is generally designed to highlight very specific characteristics of the singular trait. Thus, the
obtained results are not easily comparable between different institutions. However the data sharing is clearly
the most powerful approach to limit the costs and efforts optimizing the obtained results in term of number
of studied accessions. It should be stressed that funds are another great limit in research, especially in East
countries, where the most interesting cultivar variability is preserved.Peer Reviewe
Brief Report: Anti-Hail Nets in Viticulture: Do They Affect White Grape Quality in the Mediterranean Region?
Full text linkAnti-hail nets have been employed in viticulture to reduce the damage caused by hailstorms, but whether this strategy may have detrimental effects on grape quality in the Mediterranean region is still unknown. This study was carried out in the Salento region during the 2023 harvest to evaluate the grape microclimate and fruit quality attributes of ‘Fiano’ white grapes grown uncovered or covered with either crystal or black nets. The nets had a small but significant effect on the air temperature (about 0.3 °C and 0.1 °C higher with black and crystal nets, respectively) and relative humidity (about 1% lower with both black and crystal nets) in the grape zone. However, no significant variation was recorded for grape colouration (except for the chromaticity coordinate a*) nor for the main skin photosynthetic pigments (chlorophyll a, chlorophyll b, carotenoids), the total polyphenolic content, and the total soluble solids. Our preliminary results suggest that anti-hail nets can be effective to protect the grapevines against hailstorms and other adverse weather conditions, without having negative impacts on the colour development and bioactive compounds of white grapes in the Mediterranean region
Phenotyping Key Fruit Quality Traits in Olive Using RGB Images and Back Propagation Neural Networks
Full text linkTo predict oil and phenol concentrations in olive fruit, the combination of back propagation neural networks (BPNNs) and contact-less plant phenotyping techniques was employed to retrieve RGB image-based digital proxies of oil and phenol concentrations. Fruits of cultivars (×3) differing in ripening time were sampled (~10-day interval, ×2 years), pictured and analyzed for phenol and oil concentrations. Prior to this, fruit samples were pictured and images were segmented to extract the red (R), green (G), and blue (B) mean pixel values that were rearranged in 35 RGB-based colorimetric indexes. Three BPNNs were designed using as input variables (a) the original 35 RGB indexes, (b) the scores of principal components after a principal component analysis (PCA) pre-processing of those indexes, and (c) a reduced number (28) of the RGB indexes achieved after a sparse PCA. The results show that the predictions reached the highest mean R2 values ranging from 0.87 to 0.95 (oil) and from 0.81 to 0.90 (phenols) across the BPNNs. In addition to the R2, other performance metrics were calculated (root mean squared error and mean absolute error) and combined into a general performance indicator (GPI). The resulting rank of the GPI suggests that a BPNN with a specific topology might be designed for cultivars grouped according to their ripening period. The present study documented that an RGB-based image phenotyping can effectively predict key quality traits in olive fruit supporting the developing olive sector within a digital agriculture domain
Neglected cultivars for the Mtskheta-Mtianeti region (East Georgia): ampelography, phenology, and agro-climatology
Full text linkGeorgia is an important source of grapevine intra-specific variability for viticulture. This biodiversity can be a suitable tool to face the challenge of climate change. Nevertheless, it is important to take into account the interaction between the interest genotype and the local environment, whose climate is changing due to global heating. In this work, we put in relation the phenotypic behavior of some neglected Georgian cultivars (‘Tabidziseuli’, ‘Daisi’, ‘Qvelouri’, ‘Bazaleturi Colikouri’) from the Mtskheta-Mtianeti Georgian region to the agro-climatology of the region itself. The phenological phases and the vegetation length of these four grape varieties were described, as well as their principal ampelographic characters. The impact of global heating on the agro-climatology of the Mtskheta-Mtianeti region has also been established, by comparing the sum of active temperatures (>10°C) of multi-years (1948-2017) with those calculated for the future scenario (2020-2050, temperature increase by 2°C). Based on this comparison, three agro-climatic zones have been confirmed within the region: dry subtropical, mountain and high mountain. The scenario of temperature increase by 2°C in the next three decades will cause the sum of active temperatures to reach 3900-4000°C in the dry subtropical zone, 3400-3500°C in the mountain zone and 1900-2000°C in the high mountain zone. Considering the vegetation length of the cultivars analyzed, it can be expected a shift of the most suitable sites for viticulture from the dry subtropical zone to the mountain area. High mountain seems not to be suitable for the cultivation of the studied cultivars. Given this environmental variability within the region, the increase in temperature will not suppress viticulture in Mtskheta-Mtianeti, if the real temperature does not exceed the level predicted by scenario
Influence of freezing and heating conditions on grape seed flavan-3-ol extractability, oxidation, and galloylation pattern
Full text linkIn cool-climate viticulture, the short growing season can influence grape seed maturation by reducing the apparent oxidation of flavan-3-ol monomers and associated increase in seed browning. A reduction in seed maturation increases the potential extraction of flavan-3-ol monomers into wine during maceration operations, heightening bitterness. Here, we carried out a 2 × 2 factorial experiment to test the ability of freezing and heating treatments to advance maturation (decrease flavan-3-ol, improve browning) of (Vitis vinifera L.) Pinot noir and Cabernet Sauvignon seeds over a 24-h incubation period. Only freezing significantly increased seed browning in both cultivars. Subsequent correlations with seed flavan-3-ol monomer concentrations suggest that freezing enhanced the oxidation of these compounds. Interestingly, natural ripening and freezing reduced galloylated flavan-3-ol monomers to a greater extent than non-galloylated ones. This study provides new information regarding the susceptibility of flavan-3-ol monomers to freezing and heating, and also suggests that freezing can advance the maturation the seeds of under-ripe red vinifera grape
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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