14 research outputs found
Widespread occurrence of Tomato ring spot virus in deciduous fruit trees in Iran
Despite a long tradition of fruit-tree growing in all provinces of Iran, information on tree viruses in this country is scant. In the present study, presence of Tomato ring spot virus (ToRSV) was surveyed in various woody plants in this country by mechanical inoculation to herbaceous hosts, ELISA using a commercial antiserum, and PCR with specific primers. ToRSV was identified in the following plant-symptom combinations: Walnut with mottling, deformation, necrosis, and yellowing of main veins from Tehran Province; plum with yellowing of main veins, peach with yellowing of major veins and marginal necrosis, and hazelnut with interveinal chlorosis and marginal necrosis from Ardabil Province; apple with yellowing of main veins, mosaic and necrotic lesions, quince with large necrotic spots, and almond with leaf deformation and rosetting from Khorasan Province; and raspberry with marginal necrosis of leaf and necrotic lesions from Mazandaran Province. Mechanical inoculation from walnut, plum, peach, hazelnut, apple, quince, almond, and raspberry to Nicotiana tabacum cv. Samsun resulted in systemic infection. The virus isolates induced local lesions, leaf deformation, and necrosis in N. rustica, chlorotic local lesions on Chenopodium quinoa, and large local lesions on Gomphrena globosa. All samples were ELISA positive. PCR with specific primers resulted in the amplification of the expected fragment (490 bp). This study shows extensive occurrence of ToRSV in Iran.Keywords: Tomato ringspot virus, fruit tree viruses, Ira
Performance of the ARIANNA Hexagonal Radio Array
Installation of the ARIANNA Hexagonal Radio Array (HRA) on the Ross Ice Shelf
of Antarctica has been completed. This detector serves as a pilot program to
the ARIANNA neutrino telescope, which aims to measure the diffuse flux of very
high energy neutrinos by observing the radio pulse generated by
neutrino-induced charged particle showers in the ice. All HRA stations ran
reliably and took data during the entire 2014-2015 austral summer season. A new
radio signal direction reconstruction procedure is described, and is observed
to have a resolution better than a degree. The reconstruction is used in a
preliminary search for potential neutrino candidate events in the data from one
of the newly installed detector stations. Three cuts are used to separate radio
backgrounds from neutrino signals. The cuts are found to filter out all data
recorded by the station during the season while preserving 85.4% of simulated
neutrino events that trigger the station. This efficiency is similar to that
found in analyses of previous HRA data taking seasons.Comment: Proceedings from the 34th ICRC2015, http://icrc2015.nl/ . 8 pages, 6
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A First Search for Cosmogenic Neutrinos with the ARIANNA Hexagonal Radio Array
The ARIANNA experiment seeks to observe the diffuse flux of neutrinos in the
10^8 - 10^10 GeV energy range using a grid of radio detectors at the surface of
the Ross Ice Shelf of Antarctica. The detector measures the coherent Cherenkov
radiation produced at radio frequencies, from about 100 MHz to 1 GHz, by
charged particle showers generated by neutrino interactions in the ice. The
ARIANNA Hexagonal Radio Array (HRA) is being constructed as a prototype for the
full array. During the 2013-14 austral summer, three HRA stations collected
radio data which was wirelessly transmitted off site in nearly real-time. The
performance of these stations is described and a simple analysis to search for
neutrino signals is presented. The analysis employs a set of three cuts that
reject background triggers while preserving 90% of simulated cosmogenic
neutrino triggers. No neutrino candidates are found in the data and a
model-independent 90% confidence level Neyman upper limit is placed on the all
flavor neutrino+antineutrino flux in a sliding decade-wide energy bin. The
limit reaches a minimum of 1.9x10^-23 GeV^-1 cm^-2 s^-1 sr^-1 in the 10^8.5 -
10^9.5 GeV energy bin. Simulations of the performance of the full detector are
also described. The sensitivity of the full ARIANNA experiment is presented and
compared with current neutrino flux models.Comment: 22 pages, 22 figures. Published in Astroparticle Physic
Livetime and sensitivity of the ARIANNA Hexagonal Radio Array
The ARIANNA collaboration completed the installation of the hexagonal radio
array (HRA) in December 2014, serving as a pilot program for a planned high
energy neutrino telescope located about 110 km south of McMurdo Station on the
Ross Ice Shelf near the coast of Antarctica. The goal of ARIANNA is to measure
both diffuse and point fluxes of astrophysical neutrinos at energies in excess
of 1016 eV. Upgraded hardware has been installed during the 2014 deployment
season and stations show a livetime of better than 90% between commissioning
and austral sunset. Though designed to observe radio pulses from neutrino
interactions originating within the ice below each detector, one station was
modified to study the low-frequency environment and signals from above. We
provide evidence that the HRA observed both continuous emission from the Galaxy
and a transient solar burst. Preliminary work on modeling the (weak) Galactic
signal confirm the absolute sensitivity of the HRA detector system.Comment: Proceedings from the 34th ICRC2015, http://icrc2015.nl/, 8 pages, 6
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GRAPEVINE VIRUS DISEASES:ECONOMIC IMPACT AND CURRENT ADVANCES IN VIRAL PROSPECTION AND MANAGEMENT
Incidence, distribution and limited genetic variability among Turkish isolates of Grapevine Pinot gris virus from different grapevine cultivars
Grapevine Pinot gris virus (GPGV) was firstly identified in northern Italy by deep sequencing from grapevine cv. Pinot gris, exhibiting mottling and deformation of the leaves. The objective of this study was to investigate the prevalence and genetic variability of GPGV isolates obtained from different local and imported grapevine cultivars in Turkey based on partial coat protein, movement protein and RNA-dependent RNA polymerase (RdRp) domain of the replicase (Rep) gene. Two hundred and one grapevine samples from different provinces were tested by RT-PCR assays, approximately 25% of which were found to be infected by GPGV. The PCR products were sequenced and based on the phylogenetic analysis, RdRp gene was found to be most conserved region. The phylograms of three genomic regions revealed correlation between geography and genetic structure. Furthermore, nucleotide diversity studies revealed a low divergence from the homologous sequences from GenBank and some variations within the groups were detected. The results presented in this study provide a better understanding of genetic variation and phylogenetic of GPGV isolates worldwide. © 2018, Deutsche Phytomedizinische Gesellschaft
Human resource development through vocational education in the Uunited Arab Emirates: the case of dubai polytechnic
Identification and characterization of a novel Robigovirus species from sweet cherry in turkey
High throughput sequencing of total RNA isolated from symptomatic leaves of a sweet cherry tree (Prunus avium cv. 0900 Ziraat) from Turkey identified a new member of the genus Robigovirus designated cherry virus Turkey (CVTR). The presence of the virus was confirmed by electron microscopy and overlapping RT-PCR for sequencing its whole-genome. The virus has a ssRNA genome of 8464 nucleotides which encodes five open reading frames (ORFs) and comprises two non-coding regions, 5' UTR and 3' UTR of 97 and 296 nt, respectively. Compared to the five most closely related robigoviruses, RdRp, TGB1, TGB2, TGB3 and CP share amino acid identities ranging from 43–53%, 44–60%, 39–43%, 38–44% and 45–50%, respectively. Unlike the four cherry robigoviruses, CVTR lacks ORFs 2a and 5a. Its genome organization is therefore more similar to African oil palm ringspot virus (AOPRV). Using specific primers, the presence of CVTR was confirmed in 15 sweet cherries and two sour cherries out of 156 tested samples collected from three regions in Turkey. Among them, five samples were showing slight chlorotic symptoms on the leaves. It seems that CVTR infects cherry trees with or without eliciting obvious symptoms, but these data should be confirmed by bioassays in woody and possible herbaceous hosts in future studies. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.Javna Agencija za Raziskovalno Dejavnost RSFunding: This work was supported by TUBITAK-TOVAG grant number 213O042, the Slovenian Research Agency grant P4-0072 and by the COST Action grant number FA1407 (DIVAS)