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Tomato yellow leaf curl virus (TYLCV), a whitefly-transmitted single-stranded DNA (ssDNA) virus, causes the most important viral disease of tomato worldwide. TYLCV-mediated disease is mainly controlled via extensive insecticide sprays aiming at the whitefly vector. RNA-based vaccination was proven to be a non-transgenic approach leading to efficient plant virus control. In this work, double-stranded RNA (dsRNA) molecules deriving from sequences of the C4 and V2 genes of TYLCV-Mild were produced in vitro and topically applied onto tomato plants along with the virus (via agroinfiltration). DsC4 and dsV2 application reduced disease incidence to 23 and 46 %, respectively, while TYLCV positive control reached 64 %. Bioinformatics analysis of the virus-specific small interfering RNAs (vsiRNAs) from TYLCV-infected tomato revealed 'hot' and 'cold' spots in the TYLCV-Mild genome. Interestingly, the viral C-strand had twofold siRNA reads when compared to that of the V-strand. Overall, vsiRNAs of negative and positive polarity were almost equal (53.5 vs. 46.6 %); vsiRNAs of negative polarity prevailed at the V-strand. Stem-loop RT-PCR validated the presence of six vsiRNAs (hot or cold spots) in TYLCV-Mild-infected and dsRNA-treated tomato. The exogenously applied dsRNA was found to rapidly move systemically in tomato and was detected for 54 days post treatment (dpt). The applied dsRNA molecules were successfully processed by the Dicer-like proteins (DCLs) in tomato since small interfering RNAs (siRNAs) deriving from the dsRNA were detected for at least 54 dpt. This consists the first report of dsRNA-based vaccination applied against a monopartite geminivirus. [ABSTRACT FROM AUTHOR]

In autumn 2007, a new disease with unknown etiology was observed in open-field tomato (Solarium lycopersicum) in the Lachish region of Israel. The symptoms included mild mosaic, leaf malformation, and severe stunting of the plants. The causal agent was readily transmitted mechanically from the sap of infected plants to indicator plants. Viral particles were purified from infected plants and cDNA was synthesized from RNA isolated from the particles. Cloning and sequencing of the cDNA showed 95% identity to RNA 3 of Pelargonium zonate spot virus (PZSV). Using reverse-transcription polymerase chain reaction. PZSV was detected in both seed and pollen grains of infected tomato plants. Attempts to disinfect seed by using hydrochloric acid and trisodium phosphate failed to eliminate this PZSV detection. Seed from infected tomato plants gave rise to infected seedlings with a seed-transmission rate of PZSV of 11 to 29%. Pollen grains collected from flowers of infected plants were used to hand pollinate healthy mother tomato plants. Although none of the pollinated mother plants became infected with PZSV, 29% of the seedlings produced from seed harvested from these plants were found to be infected. This is the first demonstration that PZSV is transmitted vertically via both pollen and seed in tomato plants. [ABSTRACT FROM AUTHOR]

Tomato ( Solanum lycopersicum) production in tropical and subtropical regions of the world is limited by the endemic presence of Tomato yellow leaf curl virus (TYLCV). Breeding programmes aimed at producing TYLCV-resistant tomato cultivars have utilized resistance sources derived from wild tomato species. So far, all reported breeding programmes have introgressed TYLCV resistance from a single wild tomato source. Here, we tested the hypothesis that pyramiding resistances from different wild tomato species might improve the degree of resistance of the domesticated tomato to TYLCV. We have crossed TYLCV-resistant lines that originated from different wild tomato progenitors, Solanum chilense, Solanum peruvianum, Solanum pimpinellifolium, and Solanum habrochaites. The various parental resistant lines and the F1 hybrids were inoculated in the greenhouse using viruliferous whiteflies. Control, non-inoculated plants of the same lines and hybrids were exposed to non-viruliferous whiteflies. Following inoculation, the plants were scored for disease symptom severity, and transplanted to the field. Resistance was assayed by comparing yield of inoculated plants to those of the control non-inoculated plants of the same variety. Results showed that the F1 hybrids between the resistant lines and the susceptible line suffered major yield reduction because of infection, but all hybrids were more resistant than the susceptible parent. All F1 hybrids resulting from a cross between two resistant parents, showed a relatively high level of resistance, which in most cases was similar to that displayed by the more resistant parent. In some cases, the hybrids displayed better levels of resistance than both parents, but the differences were not statistically significant. The F1 hybrid between a line with resistance from S. habrochaites and a line with resistance from S. peruvianum (HAB and 72-PER), exhibited the lowest yield loss and the mildest level of symptoms. Although the resistance level of this F1 hybrid was not statistically different from the level of resistance displayed by the 72-PER parent itself, it was statistically better than the level of resistance displayed by the F1 hybrids between 72-PER and any other resistant or susceptible line. [ABSTRACT FROM AUTHOR]

We have developed a scale of differential hosts that enables the determination and comparison of level of resistance to Tomato yellow leaf curl virus (TYLCV) expressed by resistant tomato lines or by individual plants in a segregating population. The scale is composed of seven different homozygous tomato genotypes that exhibit different levels of TYLCV resistance, ranging from fully susceptible to highly resistant. The differential hosts composing the scale were inoculated with TYLCV under green- house conditions. Four weeks after inoculation the plants were evaluated for disease symptom severity, and virus DNA titer was determined. The different genotypes were arranged in the scale according to symptom severity score. The different genotypes were then tested under different environmental conditions, inoculated at different ages, and tested in a field experiment assaying TYLCV-induced yield reduction. While the symptom severity score of each individual resistant genotype changed under different environmental conditions, the relative position on the scale did not alter, except for one genotype. Thus, to evaluate disease resistance of a given tomato genotype, the genotype in question should be inoculated alongside the differential hosts composing the scale, and within 4 weeks one can determine the relative level of resistance of the tested genotype. [ABSTRACT FROM AUTHOR]

Reports on the tomato breeding line TY172 that exhibits high levels of resistance to the tomato yellow leaf curl begomovirus (TYLCV). Symptomless carrier of TYLCV; Effect of growth conditions on crop loss due TYLCV; Inheritance of resistance trait.

The occurrence of neuroleptic malignant syndrome (NMS) was studied prospectively in two series of consecutive psychiatric in-patients (n = 223). The first group (n = 120) suffered from schizophrenia and was treated only with haloperidol. The second group (n = 103) was treated with diverse neuroleptics. All patients were on a single antipsychotic agent with no anticholinergic drug as prophylaxis. The incidence of full NMS per admission and first neuroleptic exposure was 5/223 (2.2%). Patients with bipolar affective disorder and those treated with injections were significantly over-represented in the NMS group. [ABSTRACT FROM AUTHOR]

Abstract Aberrant right subclavian artery (ARSA) is asymptomatic in most cases. This variant anatomy can cause dysphagia in elderly patients. Impaction of foreign body in the esophagus is rarely the presenting symptom of ARSA. We present an eighty four years old patient who first presented with esophageal foreign body impaction and was diagnosed with an aberrant right subclavian artery compressing the esophagus just below the site of impaction. We assume that the exact place of impaction was not incidental and that a relative narrowing of the esophagus caused by the vascular anomaly is responsible for this specific presentation.

Five Capsicum species were tested for susceptibility to Tomato yellow leaf curl virus (TYLCV) and the mild strain of TYLCV (TYLCV-Mld). TYLCV was able to infect 30 of 55 genotypes of C. annuum, one of six genotypes of C. chinense, one of two genotypes of C. baccatum, and the only genotype of C. frutescens tested but was unable to infect the one genotype of C. pubescens tested. This is the first evidence for the susceptibility of C. baccatum, C. chinense, and C. frutescens to TYLCV. Unlike TYLCV isolates, TYLCV-Mld was unable to infect C. chinense. No host differences were observed between the Israeli and Florida isolates of TYLCV. None of the Capsicum species showed symptoms after infection with TYLCV or TYLCV-Mld. TYLCV was detected in fruits of C. annuum, but whiteflies were unable to transmit virus from fruits to plants. Whiteflies were able to transmit both TYLCV and TYLCV-Mld from infected pepper plants to tomato plants. Pepper plants in research plots were found infected with TYLCV at rates as much as 100%. These data demonstrate the ability of some genotypes of pepper to serve as reservoirs for the acquisition and transmission of TYLCV and TYLCV-Mld. [ABSTRACT FROM AUTHOR]