An Adelaide woman will stand trial for murder for allegedly killing her husband when she set his genitals alight.

Rajini Narayan, 45, is also charged with arson for the alleged attack in December 2008 which burnt the family's house at Unley.

It is alleged Narayan doused her husband's genitals with methylated spirits and ignited the liquid because she thought he was having an affair.

Narayan fought back tears as she pleaded not guilty to murder and arson in the Supreme Court.

Three charges of endangering the lives of her children were dropped but no explanation was given in court.