Pseudomonas syringae pv. tabaci produces:

Correct option is B

Pseudomonas syringae pv. tabaci is a pathovar of P. syringae, a Gram-negative, rod-shaped bacterium that causes wildfire disease in tobacco ( Nicotiana tabacum). One of the key virulence factors it produces is a phytotoxin called tabtoxin (also known as tabo-toxin).
�� Why (b) Tabo-toxins is the Correct Answer:
· Tabo-toxins / Tabtoxinine-β-lactam:
· A non-host-specific toxin produced by P. syringae pv. tabaci.
· Inhibits glutamine synthetase, leading to the accumulation of ammonia in plant tissues.
· This results in chlorosis (yellowing of leaves) and necrosis due to cell death, forming characteristic "wildfire" lesions—a necrotic center with a yellow halo.
· Role in Pathogenesis:
· The toxin is a key virulence factor, helping the bacterium spread in plant tissues and cause damage.
· Its accumulation increases host susceptibility by weakening plant cell walls and disrupting metabolic functions.