(New throughout, adds comments from traders, background)
By Walter Bianchi
BUENOS AIRES, Sept 17 (Reuters) - Argentina's peso tumbled 1.87 percent on the black market to hit a record low of 15 per dollar on Wednesday, traders said, as state interventions in the economy failed to pull the currency out of its tail-spin.
The peso has tanked more than 15 percent since the government defaulted on its debt on July 31, as Argentine businesses and savers seek refuge in dollars.
Thomson Reuters data showed the peso at a bid/ask price of 14.950/15.000.
"The market is buying dollars and there are few sellers in sight," one trader said on condition of anonymity because the black market trade, while tolerated, is illegal.
Tight capital controls mean Argentines are often forced to resort to the black market when they cannot get hold of greenbacks at the central bank-controlled official rate .
The gaping gulf between the black market and official rate, which held steady at 8.4100 per greenback, suggests the peso is over-valued. From the capital's boulevards to Wall Street, people expect a sharp devaluation before year's end.
Foreign reserves are down 19.5 percent over the last 12 months to $28.4 billion, equal to only 4-1/2 months of import cover. This gives the central bank little financial muscle with which to shore up the currency.
Instead, it is ramping up state intervention in the economy to try to prevent a balance of payments crisis but its policies are also battering business confidence and may deepen the country's recession.
In a bid to tighten the tourniquet, authorities have limited further the amount of dollars available to importers, cut the amount of hard currency commercial banks can hold and raised the minimum monthly salary that an Argentine must earn in order to buy the U.S. currency.
"It's a large fall in a short time, but there are not many options for the authorities," said a second trader.
A legal deadlock over Argentina's defaulted global bonds has kept the country locked out of international capital markets, while its foreign reserves are sinking. The dearth of dollars flowing into the recession-hit economy is intensifying pressure on the peso. (Writing by Richard Lough; Editing by Chizu Nomiyama and David Gregorio)