Does viroid cause potato spindle tuber?
Potato Spindle Tuber Viroid (PSTVd) is an EU listed quarantine pathogen of potatoes which causes stunting of the plant and malformation and cracking of tubers. The main host is potatoes but the disease also affects tomatoes and solanaceous ornamentals.
Who caused potato spindle tuber?
Viroids/Virusoids Theodor O. Diener was credited with the discovery of the first viroid, Potato spindle tuber viroid (PSTVd), in 1971. This viroid is the causal agent of potato spindle tuber disease first described in the 1920s.
Do viroids have a protein coat?
Viroids are the smallest infectious pathogens known, comprised solely of a short circular RNA without protein coats.
What does viroid mean?
viroid, an infectious particle smaller than any of the known viruses, an agent of certain plant diseases. The particle consists only of an extremely small circular RNA (ribonucleic acid) molecule, lacking the protein coat of a virus. Whether viroids occur in animal cells is still uncertain.
Which of the following is correct about Viroids?
Viroids have free RNA without protein coat (capsid).
Which virus causes potato spindle disease?
| Potato spindle tuber viroid | |
|---|---|
| Virus classification | |
| Family: | Pospiviroidae |
| Genus: | Pospiviroid |
| Species: | Potato spindle tuber viroid |
How are viroids different from viruses?
Viroids differ from viruses on six points : They exist inside the cells as RNA particles only, without capsid nor envelope. They have only one circular RNA strand which contains very little nucleotides. Unlike certain viruses, viroids do not need the help of a virus to infect a cell.
Which of the following are correct for viroids?
What is the difference between viroids and Virusoids?
Viroids consist of small, naked ssRNAs that cause diseases in plants. Virusoids are ssRNAs that require other helper viruses to establish an infection.
How many nucleotides are in viroids?
Direct biophysical and biochemical analysis on highly purified viroid molecules revealed that they consist of a single-stranded RNA molecule of about 360 nucleotides in length [32].
What is not true about viroids?
They are smaller than viruses. They cause infections. Their RNA is of high molecular weight. They lack a protein coat.
What is the molecular weight of viroids?
Presently known viroids consist solely of a low molecular weight RNA of about 75,000–130,000.
Which is the type species of potato spindle tuber viroid?
In addition to the type of CCR, the presence of either a Terminal Conserved Hairpin (TCH) or Region (TCR) allocates members of the Pospiviroidae into five genera, one of which is the genus Pospiviroid with Potato spindle tuber viroid (PSTVd) as its type species.
Are there any cases of PSTVd on potatoes in Chile?
There are no records of PSTVd on potato in Chile as the pathogen has not been detected in potato surveys, neither national seed potato certification by Servicio Agrícola y Ganadero (SAG) or by the Institute of Agricultural Research (INIA), Chile. PSTVd is a quarantine pest for Chile (Servicio Agrícola y Ganadero, 2013 ).
How many nucleotides are in the PSTVd RNA?
PSTVd is a small, unencapsidated, covalently closed, circular RNA of circa 359 nucleotides. Variants consisting of 356-363 nucleotides have been described ( Gross et al., 1978; Puchta et al., 1990; Lakshman and Tavantzis, 1993; Behjatnia et al., 1996; Verhoeven et al., 2010b ).
What kind of RNA is a viroid RNA?
Viroids are small (246-375 nucleotides), single-stranded, covalently closed, circular, unencapsidated RNAs characterized by a highly base-paired, rod-like secondary structure ( Diener, 1971, 1979, 1987).