El Salvador's rightist-dominated Constituent Assembly has suspended a U.S.-inspired "land to the tiller" agricultural reform program.

The assembly voted 37-18 Tuesday night, after a sharp debate, to cancel for one crop cycle the right of tenant farmers and sharecroppers to acquire titles for up to 17 acres of the land they work. A crop cycle lasts one year for most crops but four years for sugar cane.

The peasants' right to the land was decreed two years ago by El Salvador's ruling junta as part of an agrarian reform designed to undercut peasant support for leftist guerrillas in the civil war. But President Alvaro Magana, installed after the conservative victory in the March 28 elections, suggested suspending the program. He said landowners had no incentive to plant cotton or sugar cane because they were expecting to have their land expropriated.

Magana suggested suspending the reform program only for land devoted to cotton and sugar cane, but the members of the assembly's rightist majority decided to extend it to cattle-producing and grain lands. Among them, those four kinds of land account for 95 percent of the production on the farms involved.

The amendment made the assembly's Christian Democrats oppose the bill. "If what they want is to kill the land reform, they should call things by name and say so once and for all," Christian Democrat Deputy Antonio Guevara said during the debate. All 18 votes against the bill came from the Christian Democrats.

The agrarian reform program has been carried out with U.S. technical assistance. It is modeled after a similar program the United States supported in South Vietnam, which was also called "land to the tiller."

In the first phase the program, El Salvador expropriated estates larger than 1,235 acres, turned them into peasant cooperatives and provided compensation to former owners. An estimated 386,000 peasants, about half the country's rural poor, benefited.