1,720,963 research outputs found
Evaluation of some growth regulator effects on encapsulated in vitro-derived microcuttings of three Italian Ficus carica L. genotypes.
No full textIn this study, the encapsulation technology based on the calcium alginate coating
was applied to some Ficus carica L. genotypes. Uninodal microcuttings (3-4 mm long),
excised from in vitro proliferating shoots of three Italian cultivars (‘Bifera’, ‘Palazzo’
and ‘Catalanisca’), were employed. The influence of three different plant growth
regulators (PGRs): 6-benzylaminopurine (BAP), meta-topolin (MT) and zeatine (ZEA),
added to the artificial endosperm, were evaluated. Particularly, the viability, regrowth
and conversion parameters of the synthetic seeds were registered after 60 days from
the sowing on a hormone-free medium. Results showed that the cultivars ‘Catalanisca’
and ‘Palazzo’ showed the highest viability average rate (90%), followed by ‘Bifera’
(80%). Encapsulated microcuttings regrowth percentage was highest for ‘Palazzo’
(86.7%), followed by ‘Catalanisca’ (81.7%) and ‘Bifera’ (66.7%), while the conversion
rate was comparable for the three cultivars (43.4, 40.0 and 48.3%, respectively). A
strong interaction between cultivars and PGRs was observed. Moreover, regarding the
effect of the PGRs, BAP and MT provided the best results about regrowth and
conversion, even if the cultivar ‘Catalanisca’ presented 100% of regrowth with ZEA. To
our knowledge, this is the first time, that encapsulation technology has been applied
to Italian cultivars of Ficus carica
Alternaria species causing pomegranate and citrus fruit rots in Albania
Full text linkThe fungal genus Alternaria is a relevant pathogen for several commodities including citrus and pomegranate fruits. On citrus, it mainly causes brown spots on fruits and leaves, whereas on pomegranate, it mostly causes a fruit heart rot. In the present study the presence of Alternaria rots on citrus and pomegranate fruits cultivated in Albania was assessed. Representative fruits were collected from different regions. Nineteen and thirteen Alternaria spp. isolates were obtained from pomegranate and citrus samples, respectively. The isolates were identified at species and morphotype level. Micro and macroscopic features separated isolates into four morphotypes. BLAST and phylogenetic analysis using the SCAR Marker OPA1-3 confirmed the isolate identity. All 32 isolates proved to be Alternaria alternata and belonged mainly to morphotype alternata, followed by limoniasperae and tenuissima. All Alternaria strains proved to possess the pksI gene of alternariol biosynthesis. Citrus isolates were tested for the presence of genes of the biosynthesis of the phytotoxins ACT and ACR, but none of them proved to possess them. Concluding, Alternaria spp. might represent a treat to pomegranate and citrus production in Albania, and thus effective control means are needed
Alternaria species causing pomegranate and citrus fruit rots in Albania
Full text linkThe fungal genus Alternaria is a relevant pathogen for several commodities including citrus and pomegranate fruits. On citrus, it mainly causes brown spots on fruits and leaves, whereas on pomegranate, it mostly causes a fruit heart rot. In the present study the presence of Alternaria rots on citrus and pomegranate fruits cultivated in Albania was assessed. Representative fruits were collected from different regions. Nineteen and thirteen Alternaria spp. isolates were obtained from pomegranate and citrus samples, respectively. The isolates were identified at species and morphotype level. Micro and macroscopic features separated isolates into four morphotypes. BLAST and phylogenetic analysis using the SCAR Marker OPA1-3 confirmed the isolate identity. All 32 isolates proved to be Alternaria alternata and belonged mainly to morphotype alternata, followed by limoniasperae and tenuissima. All Alternaria strains proved to possess the pksI gene of alternariol biosynthesis. Citrus isolates were tested for the presence of genes of the biosynthesis of the phytotoxins ACT and ACR, but none of them proved to possess them. Concluding, Alternaria spp. might represent a treat to pomegranate and citrus production in Albania, and thus effective control means are needed
Interlaboratory validation of molecular and serological diagnosis of Xylella fastidiosa strain CoDiRO in susceptible host plants.
Full text linkElimination of Citrus variegation virus (CVV) by seed cryotherapy
No full textCitrus variegation ilarvirus (CVV) is one of the oldest viruses reported in Citrus, which produces crinkling, puckering and variegation of leaves in field trees and, occasionally, variegated and deformed fruits. This virus is primarily transmitted by grafting. However, no consistent data are available concerning CVV seed transmission, which is apparently low. The elimination of CVV in citrus genotypes is carried out by shoot-tip-grafting. In the case of seed sources, virus elimination directly in the seeds becomes essential. In cryotherapy, plant pathogens such as viruses, phytoplasmas and bacteria are eradicated by exposing explants to liquid nitrogen. It allows treatment of a high number of samples and results in a high frequency of pathogen-free regenerants. In this work, three polyembryonic Citrus genotypes (sour orange, mandarin and lemon), which were found infected by CVV, were used for trials of virus seed transmission and CVV elimination by dehydration/cryopreservation of the seeds. The dehydrated seeds were placed in cryovials which were then plunged into liquid nitrogen at -196°C. ISSR markers were used to discriminate between zygotic and nucellar plants after treatment. TAS-ELISA and RT-PCR were applied for CVV detection in the seed components before cryopreservation and in the produced seedlings after treatment. CVV seed transmission was assessed for the first time in sour orange and lemon genotypes by serological and molecular means. All tested Citrus genotypes showed CVV infection in both components of the seed plunged in liquid nitrogen. However, all plantlets developed from cryopreserved seeds were CVV-free 2 years after transplanting
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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