Buhari tried to win back investors for Africa's largest but stumbling economy on Wednesday by inaugurating his cabinet after a long vetting period he had said was necessary to avoid corruption.
He had been virtually in sole charge since taking office in May, with ministries run only by senior civil servants, a practice that had prompted opposition charges of autocracy.
Finance Minister Adeosun trained in accountancy in Britain. She recently served as finance commissioner of Nigeria's southwestern state of Ogun and was a former manager with auditing firm Pricewaterhouse Coopers.
Growth in Nigeria is currently running at just 2.35 percent, while inflation is creeping towards 10 percent.
Avoiding 'mistakes of the past'
During Wednesday's ceremony at his official residence, Buhari said he had picked ministers on the basis of their abilities and performance so as "not to repeat the mistakes of the past."
His line-up reduces the number of ministries from 36 to 24, making some nominees only junior ministers. The new cabinet includes seven women and comprises appointees from each of Nigeria's 36 states.
Nigeria's new foreign minister is Geoffrey Onyeama, an intellectual property lawyer. James Ocholi was named justice minister.
Dan-Ali becomes defense minister
The defence portfolio went to retired Brigadier-General Muhammad Mansur Dan-Ali, who faces the task of fighting Boko Haram Islamist insurgents.
Since taking office, Buhari had given priority to that battle. Since 2009, insurgency has cost Nigeria at least 17,000 lives and left more than 2.5 million people homeless.
Dan-Ali was preferred over former army chief Abdulrahman Dambazau, who was appointed interior minister.
Buhari to head oil ministry
The 72-year-old Buhari, who is keen to diversify Nigeria's economy, confirmed that he would himself head Nigeria's petroleum ministry so he could oversee reforms.
"Speaking here is the substantive minister of petroleum resources," Buhari told his audience at the state house.
Nigeria's murky oil and gas sector has been hit by low global prices that have also slashed national revenues. Nigeria's central bank estimates that 90 percent of the nation's foreign exchange is earned via its oil sector.
Junior oil minister will be Emmanuel Ibe Kachikwu, who currently heads the state oil firm NNPC.
The new cabinet's minister for industry, trade and investment is Okechukwu Enelamah, who had headed Nigeria's biggest private equity firm African Capital Alliance.
Campaign allies get housing and transport
Former Lagos state governor Babatunde Fashola became minister for power, works and housing.
Former Rivers state governor Rotimi Amaechi got transport.
Fashola and Amaechi are both political heavyweights in Buhari's All Progressives Congress (APC) party.
Amaechi served as Buhari's campaign manager during elections in March.
Stasis, stranded cargos
The editor-in-chief of Nigeria business analyst firm Stears told the news agency AFP that Nigeria's "political stasis" since May had left cargos stranded at ports and delayed spending decisions.
"Too many parts of the economy have stalled as economic agents await government clarity," he said.
Sylvester Odion Akhaine, a senior lecturer at the Lagos State University, told the German news agency DPA that the new cabinet was "not likely to bring anything
new, it is not a cabinet of change."
ipj/kms (AFP, Reuters, AP, dpa)