Police said Dhandapani and his wife Laxmi (48) frequently used to quarrel over various issues.
Yesterday, they entered into a heated argument over some issue and in a fit of rage, Dhandapani doused his wife with kerosene and set her ablaze, they said.
Hearing her screams, neighbours rushed in, doused the flames and got her admitted to the government hospital here.
Police said Laxmi in her dying declaration, said her husband had set her ablaze and that he used to mentally and physically harass her for the past 20 years.