Mr Wood, an Independent, made an emotional speech in the Legislative Assembly on Thursday night, saying he would be retiring.

He'd concentrate on caring for his wife of more than 45 years, Imelda, who had been diagnosed with vascular dementia 18 months ago.

Mr Wood held the balance of power and supported the Paul Henderson Labor Government when it fell into minority in 2009, despite the 68-year-old being a self-proclaimed conservative with a strong anti-abortion stance.

He was elected in 2001 to Nelson, which is a rural electorate close to Darwin, which has traditionally been an Independent-held seat.

"I am hoping this will enable good Independents who want to stand to get themselves known around the rural area, because the rural area needs an Independent, not a member of a political party," Mr Wood said.

"Independents need to stick up for the rural area and not let the politicians, planners and developers erode our lifestyle by slowly turning parts of the rural areas into suburbs."

He was occasionally quoted in the NT News as having seen UFOs in his electorate, which were "unknown" objects and not necessarily extraterrestrial.

He also spent 13 years in local government, including as mayor of Litchfield, leading a successful campaign against the damming of the Elizabeth River.

He recently supported a call to discuss merging the Northern Territory with South Australia in the midst of a budget and financial crisis.

Australian Associated Press