Production of tobacco mosaic virus in and its infectivity from leaves of two Nicotiana species treated with 6-azauracil

1969 ◽  
Vol 75 (6) ◽  
pp. 321-328 ◽  
Author(s):  
Jeanne Dijkstra
1977 ◽  
Vol 83 (2) ◽  
pp. 41-59 ◽  
Author(s):  
Jeanne Dijkstra ◽  
G. C. A. Bruin ◽  
Ankie C. Burgers ◽  
L. C. Loon ◽  
Christien Ritter ◽  
...  

2018 ◽  
Vol 54 (No. 3) ◽  
pp. 143-146 ◽  
Author(s):  
Depta Anna ◽  
Kursa Karolina ◽  
Doroszewska Teresa ◽  
Laskowska Dorota ◽  
Trojak-Goluch Anna

Tobacco mosaic virus (TMV) brings increasing losses in the cultivation of tobacco. Sixty-two cultivars of tobacco and eleven species of Nicotiana were evaluated for resistance to TMV. Biological tests at two temperature ranges, DAS-ELISA and molecular markers were applied to assess the resistance to TMV. Most cultivars of tobacco showed susceptibility (S) to TMV, two were tolerant (T), while others revealed a hypersensitive response (HR). Hypersensitivity, determined by the N gene, occurred only at a temperature below 22°C. At a temperature above 28°C, all the cultivars showed mosaic discolorations or extensive necrosis. The reaction of the Nicotiana species was dependent on growth conditions. At 22°C, the reactions of sensitivity, tolerance and hypersensitivity to TMV were all observed, whereas above 28°C the species showed systemic necrotic symptoms. N. gossei was an exception because hypersensitivity occurred regardless of the thermal conditions. The resistance of this species was not conditioned by the N gene, which suggests that N. gossei could be an additional genetic resource for tobacco breeding.  


2015 ◽  
Vol 8 (12) ◽  
pp. 1813-1815 ◽  
Author(s):  
Xinjie Yuan ◽  
Chenghuan Yan ◽  
Zhujun Wu ◽  
Feihong Ren ◽  
Hui Zhang ◽  
...  

Author(s):  
Irwin Bendet ◽  
Nabil Rizk

Preliminary results reported last year on the ion etching of tobacco mosaic virus indicated that the diameter of the virus decreased more rapidly at 10KV than at 5KV, perhaps reaching a constant value before disappearing completely.In order to follow the effects of ion etching on TMV more quantitatively we have designed and built a second apparatus (Fig. 1), which incorporates monitoring devices for measuring ion current and vacuum as well as accelerating voltage. In addition, the beam diameter has been increased to approximately 1 cm., so that ten electron microscope grids can be exposed to the beam simultaneously.


Author(s):  
Egbert W. Henry

Tobacco mosaic virus (TMV) infection has been studied in several investigations of Nicotiana tabacum leaf tissue. Earlier studies have suggested that TMV infection does not have precise infective selectivity vs. specific types of tissues. Also, such tissue conditions as vein banding, vein clearing, liquification and suberization may result from causes other than direct TMV infection. At the present time, it is thought that the plasmodesmata, ectodesmata and perhaps the plasmodesmata of the basal septum may represent the actual or more precise sites of TMV infection.TMV infection has been implicated in elevated levels of oxidative metabolism; also, TMV infection may have a major role in host resistance vs. concentration levels of phenolic-type enzymes. Therefore, enzymes such as polyphenol oxidase, peroxidase and phenylalamine ammonia-lyase may show an increase in activity in response to TMV infection. It has been reported that TMV infection may cause a decrease in o-dihydric phenols (chlorogenic acid) in some tissues.


2018 ◽  
Author(s):  
Madushani Dharmarwardana ◽  
André F. Martins ◽  
Zhuo Chen ◽  
Philip M. Palacios ◽  
Chance M. Nowak ◽  
...  

Superoxide overproduction is known to occur in multiple disease states requiring critical care yet non-invasive detection of superoxide in deep tissue remains a challenge. Herein, we report a metal-free magnetic resonance imaging (MRI) and electron paramagnetic resonance (EPR) active contrast agent prepared by “click conjugating” paramagnetic organic radical contrast agents (ORCAs) to the surface of tobacco mosaic virus (TMV). While ORCAs are known to be reduced <i>in vivo</i> to an MRI/EPR silent state, their oxidation is facilitated specifically by reactive oxygen species—in particular superoxide—and are largely unaffected by peroxides and molecular oxygen. Unfortunately, single molecule ORCAs typically offer weak MRI contrast. In contrast, our data confirm that the macromolecular ORCA-TMV conjugates show marked enhancement for <i>T<sub>1</sub></i> contrast at low field (<3.0 T), and <i>T<sub>2</sub></i> contrast at high field (9.4 T). Additionally, we demonstrated that the unique topology of TMV allows for “quenchless fluorescent” bimodal probe for concurrent fluorescence and MRI/EPR imaging, which was made possible by exploiting the unique inner and outer surface of the TMV nanoparticle. <a>Finally, we show TMV-ORCAs do not respond to normal cellular respiration, minimizing the likelihood for background, yet still respond to enzymatically produced superoxide in complicated biological fluids like serum.</a>


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