More than 1,000 Montgomery County employes have signed petitions that oppose a proposal by County Executive Charles W. Gilchrist to make Martin Luther King's Jan. 15 birthday a county holiday in place of the current county holiday on Maryland Day, March 25.

Gilchrist's proposal, which he said he made in response to a growing number of racial incidents in the county, would result in no new holidays. Instead, the county's 4,542 employes, 753 of whom are black, would be given a day off on King's birthday rather than on Maryland Day.

The county's professional workers' organization, the Montgomery County Government Employees Organization representing nearly 2,000 workers, has gone on record against the proposal.

"We think there should be a holiday for Martin Luther King but not as a substitute for something else," said Thelma Bourke, president of the employes' organization. Bourke said the majority of county workers want to keep Maryland Day as a holiday because otherwise there would be no holiday between Jan. 1 (New Year's Day) and May 30 (Memorial Day).

"I do not object to Martin Luther King Memorial Day . . . ," one opponent wrote to the county, "when it becomes a national holiday."

"It doesn't really surprise me," said Roscoe Nix, president of the county chapter of the NAACP, of the opposition. "The fact is that Montgomery County is also a county where blacks are not employed in the government system very much, and it only follows that in this kind of situation it's very difficult for many whites to believe a black person should have a holiday . . . Not all problems of race come from the Klan."

Many of the opposition petitions reflected the employe organization's position, that if the county wanted a King holiday, it should be in addition to Maryland Day. A number of letters and petitions also argued that there are enough winter holidays already.

The King holiday would bring Montgomery in line with school board vacations. Maryland government offices are closed on Jan. 15, as are 18 county and city offices in the state. In the Washington area, the District of Columbia, Alexandria and Prince George's County observe King's birthday. State offices and county school offices do not close on Maryland Day.

The council is expected to approve the change June 22.