A particular type of virus carries a gene for salicylate hydroxylase, an enzyme that breaks down salicylic acid. Which of the following responses is most likely?
A) The virus will be more virulent because systemic acquired resistance will be blocked.
B) The virus will be less virulent because the hypersensitive response will no longer function.
C) The host will be more susceptible because the hypersensitive response will no longer function.
D) There will be no difference in virulence because salicylic acid affects only fungal pathogens.

Question

Quizplus · Accepted Answer

Salicylic acid is a key signaling molecule in plants that activates systemic acquired resistance (SAR), a broad-spectrum immune response against pathogen attack. A virus carrying a gene for salicylate hydroxylase, which breaks down salicylic acid, would likely be more virulent because it can effectively disarm the plant's SAR, making the plant more susceptible to infection.

A Particular Type of Virus Carries a Gene for Salicylate