1,720,972 research outputs found
Alternative technologies to control postharvest diseases of kiwifruit
No full textThe review deals with alternative technologies to conventional synthetic fungicides to control
kiwifruit postharvest diseases. Prolonged and intensive use of these fungicides raises concerns regarding the safety of their residues in fruit and has caused the emergence of fungicide resistant pathogen strains. Alternative treatments were investigated, such as hot water, biological control agents (BCAs), and natural substances. Kiwifruit production is economically important in many parts of the world, but little is known about
means of controlling its postharvest diseases. Many fungi cause postharvest rot of kiwifruit, and their occurrence varies among the production areas. Ripe-rot caused by Botryosphaeria dothidea and stem-end rot caused by Diaporthe actinidiae prevail in New Zealand, while stem-end rot caused by Botrytis cinerea is the most important postharvest disease of the kiwifruit cultivated in Europe and USA, while in these regions skin pitting by Cadophora luteo-olivacea
and Mucor rot caused by Mucor piriformis are less important. In terms of control technique, curing, which is a delay between harvesting and cool storage of fruit, remains an important and safe tool to reduce postharvest losses, but improvements in it are needed. Innovative non-chemical treatments include hot water dipping (45°C for 10 min) for controlling several diseases which has received commercial attention. The application of BCA following curing
for 96 h was demonstrated to be effective against B. cinerea. Some natural compounds controlled grey mould well in artificially and naturally infected fruit
First report of Stemphylium eturmiunum causing postharvest rot of sweet cherry in Italy
No full textItaly is the first producing country of sweet cherries in Europe. In June 2019, sweet cherry fruit showing rot symptoms were collected from retailers located in Apulia (Southern Italy). Marginal pieces of rotted tissue of surface-sterilized fruit were plated onto semi-selective PDA medium. Colonies were further purified and grown on Potato Carrot Agar (PCA), looking initially whitish and then turning pale olive green to light brown. Conidia were septate and broadly ovoid or ellipsoid. Based on its micro- and macro-morphological features, the pathogen was identified as Stemphylium eturmiunum E.G. Simmons. A multi-locus approach was applied to confirm the identification. ITS-rDNA region and portion of genes coding for the glyceraldehyde-3-phosphate dehydrogenase and the calmodulin were sequenced. Both nBLAST homology and phylogenetic analysis confirmed the pathogen as S. eturmiunum. To fulfil Koch's postulates, surface-sterilized sweet cherry fruit, cv. Ferrovia, were inoculated with the strain. Typical disease symptoms were recorded after 7 days and the pathogen's identity was confirmed by re-isolation and characterization. Because of the resemblance with the symptoms caused by Alternaria spp., reasonably the incidence of S. eturmiunum infections might have been underestimated. This is the first report of S. eturmiunum as causal agent of postharvest rot of sweet cherries in Italy. © 2020 Elsevier Lt
First Report of Colletotrichum acutatum Causing Bitter Rot on Apple in Italy
No full textItaly could be considered the main apple-producing country in the European Union. Italian apple (Malus domestica L. Borkh.) production is estimated at approximately 2,100 million tons and encompasses a wide range of varieties, harvested from August to November. Colletotrichum acutatum, which causes severe losses to strawberry production, was a regulated organism for all European countries until 2008, when it was removed from the EPPO quarantine pathogen list because of its wide distribution in strawberry production areas. During the growing season of 2010, fungi were isolated from apple fruits exhibiting bitter rot symptoms after four months of storage in several packinghouses in the Emilia Romagna region. The apples belonged to the ‘Golden Delicious’, ‘Granny Smith’, Pink Lady’ and ‘Crisp Pink’ varieties. Lesions on the fruit surface were circular and 1 to 3 cm in diameter. When lesions enlarged, they became sunken with relatively firm rotten tissues. The fungal fruiting structures, acervuli, were distributed sparsely or densely on old lesions, and under humid conditions, they discharged an orange conidial mass. Conidia observed under a light microscope appeared hyaline and fusiform, sized 8 to 16 x 2.5 to 4 μm, with two pointed ends or one rounded end. The fungal isolates were grown on potato dextrose agar (PDA) plates incubated at 25°C
Physical and Chemical Control of Postharvest Diseases
No full textMicrobial decay is a major factor responsible for postharvest losses and compromises to the quality of fresh produce. In the past, the use of new fungicides has extended the shelf-life of fresh fruits by reducing losses, but in the last two or three decades, concerns about public health and the environment has considerably limited their use after harvest. Future scenarios are tending increasingly more towards integrated crop management and organic fruit production, with a consequent reduced use of fungicides, for a sustainable agriculture system. This goal requires new technologies to control postharvest disease. Intense research in the last 30 years has produced numerous studies that show significant progress in the reduction of pesticide use for disease control, although some critical points have still to be considered. It is unrealistic to assume that the physical and chemical methods described above have the same fungicidal activity as pesticides, and an integrated approach appears the best method to obtain acceptable results. However, further research is needed to investigate the activity of GRAS compounds, natural compounds and VOCs, in large-scale experiments, their mode of action and their degradation in organisms that are still not fully understood. Physical methods probably have a better chance of prompt application on a commercial scale since some of these, like heat, do not require any registration. Nevertheless, also in this case, more investigations have to provide additional information on appearance, texture, flavors, and storability of treated fruit. Finally, research should lead to the development of appropriate tools to tailor a complete integrated disease management strategy specific for each situation that takes into account factors such as species, climate and seasonal conditions, and the market destination
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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