Question
Biology Question on biological classification
Potato spindle tuber disease is caused by
A
Fungus
B
Virus
C
Bacterium
D
Viroid
Answer
Viroid
Explanation
Solution
Potato spindle tuber disease is caused by viroid. It occurs in tomato and potato. This disease is caused by a viroid named as Potato Spindle Tuber Viroid (PSTVd). Viroids are single-stranded RNA molecules. They are considered to be the smallest plant pathogens ranging from 246 to 399 nucleotides.
PSTVd was the first viroid identified. It contains a small, circular RNA molecule similar to the Chrysanthemum stunt viroid. The natural hosts for these viroids are tomatoes and potatoes.