BUENOS AIRES, Dec 1 (Reuters) - A wage strike by grains inspectors and oilseed workers that had halted activity at some Argentine grains ports was scheduled to end early on Wednesday morning after what will have been 24 hours, a spokesman for one of the striking unions said late on Tuesday.

The Urgara group representing grain inspectors and an oilseed workers union started an open-ended strike on Tuesday morning, after weeks of talks failed to yield a contract.

"The strike will end at 6 in the morning," Urgara spokesman Juan Carlos Peralta told Reuters. He said the union would hold a meeting of its members to determine the labor group's position when contract negotiations resume.

The work stoppage affected a few ports in the ports hub of Rosario, from which most Argentine farm exports are shipped. Peralta said that in addition to Rosario, ships were stalled in Quequen and Bahia Blanca, further south in the province of Buenos Aires, with activity in both ports "paralyzed."

A spokesman for the Argentine Federation of Oilseed workers, which had joined the strike, said participation by workers was "practically total" in many Argentine oilseed crushing plants, which manufacture soymeal feed used to fatten poultry and hogs from Europe to Southeast Asia.

The CIARA-CEC chamber of export companies said on Tuesday that it was trying to resume contract talks with the unions despite wage hike demands it described as "excessive."

On Tuesday night the United Maritime Workers Union (SOMU), announced in a statement that its members would now go on a strike of unspecified length after the failure of wage negotiations. A strike by SOMU last year lasted 72 hours and stopped shipments in three of Rosario's terminals.

Argentina is the world's top exporter of soymeal and a major international soybean, wheat and corn supplier.

With fewer grains workers available to check cargos coming into port, 1,306 trucks carrying grains entered terminals in the Rosario area from midnight to 7 a.m. on Tuesday. That marked a 45% drop compared with the same period on the same day a week earlier, according to Rosario grains exchange data. (Reporting by Maximilian Heath; Writing by Hugh Bronstein; Editing by Alexander Smith, Marguerita Choy and Sandra Maler)