Beca appeared in Nelson District Court today and was remanded in custody to appear next on March 27.
Ms Corbett's 5-year-old daughter was thought to have been in the car alongside the body of her mother, according to Fairfax.
Detective Senior Sergeant Wayne McCoy said Ms Corbett was believed to have been killed yesterday morning between Murchison and Nelson.
The girl was now in the custody of Child Youth and Family until her grandparents could pick her up.
CYF southern regional director Kelly Anderson said the little girl's situation was tragic and deeply distressing.
"She is five and she has just lost her mother. It's impossible to imagine what she must be going through. She is in CYF care and we are providing her with all the support we can, while longer term care arrangements are being discussed with her family.
"This is a very difficult time for all the family and they have our deepest sympathies."