Abstract: Vivotoxin designates a secondary metabolite produced by the pathogen and/or its host during infection, produces disease symptoms, but is not oneself the initiating causal agent of the infection. Out of all, Fusaric-acid is the most studied pathogen produced wilt toxin classified as a non-specific vivotoxin. It does not produce all the symptoms of wilt. Many scientists all over the world including India were of the belief that, out of all other toxins involved in the infection process of wilting, fusaric acid was the most potent one. Infected tissue shows a marked increase in respiration process which is contrary to the host tissues doped with fusaric acid because it is a best-known respiratory depressant.