1,720,969 research outputs found
First Report of Colletotrichum acutatum Causing Bitter Rot on Apple in Italy
Italy 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
Monilinia fructicol, Monilinia laxa (Monilinia Rot, Brown Rot)
Monilinia spp. causing brown rot is a fungal pathogen producing severe losses in worldwide stone fruit production, with high economic relevance (M€ 1.7/year). There are three main fungal species: Monilinia laxa, M. fructigena and M. fructicola. The pathogen infects aerial parts of host plants with a variety of symptoms, including blighting of blossoms, cankers on woody tissues and rotting of fruits, although the prevalent fruit losses are in the postharvest phase. Fungicide sprays in pre and postharvest periods are usually used to control Monilinia spp., but in Europe no fungicide fruit treatments are allowed after harvest. Many studies conducted in recent years have defined three main research fields within the alternative methods for postharvest brown rot control: i) biological control sensu strictum with microbial antagonists, ii) use of natural bioactive compounds and iii) use of physico-chemical methods. Although the reviewed results have reported a significant reduction of pesticide use, recommend a multidisciplinary approach in the future, where biological products will be combined with low risk chemical fungicides, natural antimicrobial substances and other physical means for an integrated strategy to control brown rot
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
First report of Asiatic brown rot (Monilinia polystroma) and Brown rot (Monilinia fructicola) on pears in Italy
Brown rot caused by Monilinia spp. is an important fruit postharvest decay causing severe losses in stone and pome fruits with a significant economic impact. In Italy, three Monilinia species (M. laxa, M. fructicola, and M. fructigena) are the causal agents of blossom and twig blight and brown fruit rot in stone fruit. M. polystroma has been observed on peaches in Italy (2) and has been reported in Czech Republic and Hungary (3), Poland (4), Serbia (5), and Switzerland (1) on pome fruits and apricots. In September 2013, stored var. Abate Fetel pears showing brown rot symptoms were observed in Emilia Romagna region. In 20% of the symptomatic pears, circular and brown to black decay spots were observed, covered by a large number of yellowish or buff-colored stromata, while decayed tissues remained firm, resembling M. polystroma symptoms. In another 13% of stored pears, the decayed tissues remained firm, and decay lesions were covered with numerous grayish pustules containing spores. Putative pathogens were isolated on potato dextrose agar (PDA) and incubated at 25°C in darkness for 5 days. The colonies grown on PDA were yellowish, with irregular black stromatal crusts at the edges of the colonies after 10 to 12 days of incubation. Some colonies developed, at their margins, sporogenous tissue slightly elevated above the colony surface that was buff/pale luteous (4). Conidia developing from such cultures were one celled, ovoid or limoniform, smooth and hyaline, measuring 12.2 to 20.4 × 8.4 to 12.3 μm when grown on V8 juice agar (V8) at 22°C, and matched the description of those for M. polystroma. Other colonies, which developed a gray mass of spores in concentric rings with the reverse side black, were morphologically identified as M. fructicola. The colony margins were smooth edged, and the conidia were one-celled, limoniform, hyaline, and measuring 12.1 to 17.4 × 8.1 to 11.2 μm on V8 at 22°C. Isolate identificaton was obtained using the universal primers for Monilinia spp. (3). Pathogenicity was confirmed using surface-sterilized mature var. Abate Fetel and William pears wounded with a sterile needle, and inoculated with 20 μl of an M. polystroma or M. fructicola conidial suspension (103 spores/ml). After 7 days of incubation at 20°C, typical symptoms of Asiatic brown rot or brown rot developed on both the wounds of all inoculated pears, while controls remained symptomless. Mean colony diameters measured after 7 days were 47.3 mm for Asiatic brown rot and 44.1 mm for brown rot, and there were no significant differences in colony diameter after 7 days between M. polystroma and M. fructicola (α < 0.05). After 14 days, yellowish exogenous stromata appeared on the surface of pears infected by M. polystroma, whereas numerous grayish pustules containing spores appeared on pears inoculated with M. fructicola. Control pears still remained symptomless. The fungus isolated from inoculated fruit exhibited the same morphological features as the original isolates, and PCR/sequencing analysis using primers ITS1 and ITS4 confirmed the results of the universal primers (3) (GenBank Accession Nos. GU067539.1 and HQ893748.1). Although the presence of M. polystroma and M. fructicola has been documented in Italy, this is the first time these two species were observed on Italian pears. This report suggests a broader impact since M. polystroma and M. fructicola have not been previously reported on pears in Europe. Because of the importance of pears in the Italian fruit industry, knowledge about the occurrence of new pathogens will facilitate the adoption of adequate control strategies to reduce postharvest losses
Appropriate Similarity Measures for Author Cocitation Analysis
We 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
We 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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