(Updates with market close, farm strike lifted)
BUENOS AIRES, March 28 (Reuters) - The Argentine peso firmed on Friday, snapping a three-session losing streak on signs that a farmers strike would end, but bonds slipped after JP Morgan recommended selling Argentine debt, traders said.
After the close of the markets, Argentine farming leaders called off their 16-day strike to start negotiations with the government.
In informal trade between foreign exchange houses, as measured by Reuters, the peso ARSB= firmed 0.39 percent to 3.1825/3.1850 per dollar, after three days of losses because the farm strike pinched the supply of dollars to the market.
In formal interbank trade, where the central bank regularly intervenes, the peso closed stable at 3.1625/3.1650 ARS=RASL.
"The market is adjusting to signs of the farmers ending the strike and exports pumping dollars in the market anew," a currency trader said.
On the bond market, government debt prices <AR/BONOS> fell 0.7 percent on average after investment bank JP Morgan recommended late on Thursday selling Argentine bonds due to the farm protest.
The losers were led by the peso-denominated Boden 2014 bond, which shed 1.4 percent, and the same bond denominated in dollars, which dropped 1.2 percent.
JP Morgan adjusted its portfolio, selling 3 million Bonar bonds maturing in 2011 at $91.50. For details, see [ID:nN27453765].
Argentine stocks closed with light gains for a fourth straight session in unusually light trade marked by investor caution over the farm strike.
The benchmark MerVal .MERV index rose 0.29 percent to 2,089.71 points, after rising as much as 0.56 percent earlier in the session.
Traders said optimism for an end to the farm strike meant the MerVal resisted the downward influence of outside markets.
Winners included aluminum producer Aluar ALU.BA, which gained 2.25 percent to 5.9 pesos per share, while Banco Patagonia BPAT.BA shed 3.64 percent to 2.65 pesos.
On the broad market, volume was a weak $15.1 million -- its lowest level since mid-February. Of the active issues, 25 advanced, 27 declined and 17 ended unchanged. (Reporting by Jorge Otaola and Walter Bianchi; Writing by Gaspard Sebag, Editing by Andrea Ricci)