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First report of apple bitter rot caused by colletotrichum fioriniae in brittany, France
No full textFrance is the third largest European producer of apples (Malus domestica), after Poland and Italy, with 2.1 million tons yearly (Eurostat 2015), and the largest producer of European cider apples, with 8,500 ha and 250,000 tons of fruit. Cider apples from Brittany represent over a quarter of the national tonnage (Anonymous 2012). Apple bitter rot symptoms have been observed on ‘Galeuse’ apples (a local variety in Brittany) for nearly 5 to 7 years and again in September 2015, during harvest at one apple orchard near Brest, France. Lesions were round, 1 to 4 cm in diameter, brown and dry with acervuli, producing orange spore masses in concentric rings. Fungal isolates were obtained from symptomatic apples by culturing necrotic tissue pieces on potato dextrose agar at 25°C in the dark. Cultures were light gray, with cottony aerial mycelium becoming darker with age and with reverse colors ranging from brownish pink to dark gray with black spots. Cultures had dark melanized structures similar to acervuli that oozed orange-colored conidia. Conidia were cylindrical to fusiform, pointed at one or both ends, and 10.0 to 14.0 μm × 3.0 to 3.5 μm. Both cultural and morphological characteristics were similar to those described for Colletotrichum acutatum sensu lato (Damm et al. 2012). Total genomic DNA was extracted and the ITS region of rDNA was amplified using the universal primers ITS4 and ITS5, then sequenced. The resulting sequence was 100% identical to C. acutatum species complex sequences obtained by a BLAST search in GenBank. Based on Damm et al. (2012), five other loci were used to further characterize the isolate: partial GAPDH, CHS-1, HIS3, ACT, and TUB2 genes sequences were amplified and sequenced. Sequences were deposited in GenBank (Accession Nos. KT887552 for ITS, KT887551 for TUB, KT887555 for CHS, KT887553 for HIS3, KT887556 for ACT, and KT887554 for GAPDH). The multilocus phylogenetic analysis carried out with the obtained sequences and reference sequences (Damm et al. 2012) revealed that the isolate clustered within C. fioriniae, as also suggested by the BLAST results, and consistent with the initial identification as C. acutatum. Koch’s postulates were performed on 10 ‘Golden Delicious’ apples. Surface sterilized fruits were wound-inoculated with 20 μl of a conidial suspension (105 conidia/ml). After 10 days incubating at 20°C, symptoms identical to those initially observed developed around the inoculation point, while controls inoculated with water remained symptomless. Fungal colonies reisolated from the lesions were morphologically similar to the original isolate. Previous studies have demonstrated that this pathogen is present worldwide on Malus spp., and apple bitter rot is considered one of the most important diseases in the United States (Ivic et al. 2013). In Europe, there are increasing numbers of reports ofColletotrichum species on apples (Ivic et al. 2013; Baroncelli et al. 2014), but to our knowledge, this is the first report in France of anthracnose on apples caused by C. fioriniae. In Europe, bitter rot caused by C. acutatum species may become a major problem and require additional investigation
First report of Colletotrichum fructicola causing apple bitter rot in Europe
No full textBitter rot is one of the prevalent diseases of apple (Malus pumila Mill.) worldwide. The disease affects the fruit preharvest in orchards and/or postharvest in storage, resulting in considerable economic losses. Until recently the reported causal agents in Europe belong to the Colletotrichum acutatum species complex (Baroncelli et al. 2014; Nodet et al. 2016); however, species belonging to C. gloeosporioides species complex were reported in the United States (Munir et al. 2016), South America (Velho et al. 2018), Korea (Park et al. 2018), and recently in Belgium (Grammen et al. 2019). In September 2017, bitter rot symptoms were observed on apple fruit (cultivars Joya Cripps Red, Granny Smith, and Pink Lady) in four orchards in the region of Occitanie in France. The rot began as circular brown spots, 1 to 2 mm in diameter, which enlarged rapidly. Sixteen isolates were obtained from symptomatic apples by culturing pieces of necrotic tissue on potato dextrose agar. Cultures showed light-gray, cottony mycelium that became darker with age, with the reverse color being brownish and becoming black with age. Conidia were produced in small orange masses and were mainly cylindrical, with rounded ends. For all isolates, the production of perithecia was observed in culture, and asci and ascospores were observed under the microscope. The width and length of 50 conidia were examined and ranged from 3.1 to 4 μm (average 3.5 μm) and from 8 to 13 μm (average 10.5 μm), respectively. Based on these morphological characteristics, those isolates correspond to teleomorph of species belonging to C. gloeosporioides species complex (Weir et al. 2012). Total genomic DNA was extracted from the 16 isolates, and the internal transcribed spacer region of rDNA was amplified using the universal primers ITS4 and ITS5 and then sequenced. For all isolates, the resulting sequences were 100% identical to C. fructicola sequences obtained by a BLAST search in GenBank. Three other loci (partial GAPDH, TUB2, and ApMat genes) were amplified and sequenced to further characterize two isolates (UBOCC-A-118064 and UBOCC-A-118065; GenBank accession nos. MK114103 to MK114110, respectively). Multilocus phylogenetic analysis carried out with the obtained and reference sequences (Da Lio et al. 2018) revealed that the isolates clustered within C. fructicola, as suggested by the BLAST results; this is also consistent with their initial identification as C. gloeosporioides. To confirm Koch’s postulates, for the two characterized isolates, 10 ‘Golden Delicious’ apples were surface sterilized and then wound inoculated with 20 μl of a conidial suspension (105 conidia/ml). After 10 days of incubation at 20°C, symptoms identical to those initially observed developed around the inoculation point, whereas controls inoculated with water remained symptomless. Fungal thalli reisolated from the lesions were morphologically similar to the original isolate. To our knowledge, this is the first report in Europe of C. fructicola causing bitter rot on apple. According to Munir et al. (2016), C. fructicola was reported to be more aggressive than species belonging to the C. acutatum species complex such as C. fioriniae previously identified in France (Nodet et al. 2016); moreover, this species is associated with Glomerella leaf spot, an emerging leaf disease never described in Europe (Velho et al. 2018). All those points encourage the development of species-specific management strategies for this pathogen in European countries
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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