The Democratic chairman of Northern Virginia's legislative delegation, turning up the political heat on the Fairfax County School Board, has rejected the board's invitation to an annual dinner because six of its members signed a letter supporting Republican gubernatorial candidate Wyatt B. Durrette.

Sen. Clive L. DuVal (D-Fairfax) wrote School Board Chairman Mary E. Collier that he was "deeply disturbed" by the letter signed by her and five others designed to "promote to the voters the political fortunes of Wyatt Durrette."

"I have never before known members of the Fairfax County School Board to involve themselves in politics by placing their names on literature" promoting a candidate, DuVal wrote Collier in rejecting an invitation to tonight's annual dinner of local legislators and School Board members to discuss education issues of the upcoming General Assembly.

Although DuVal's letter said he would continue to push the board's interests in the General Assembly, it was one more indication of widening political rifts on a School Board that usually prides itself on getting along. The 10 board members are not political innocents -- many campaign for the supervisors who appoint them -- but some say they are stepping into politics more aggressively this year than in the past.

Several appeared with gubernatorial candidates during the campaign. Then, with two weeks remaining before the election, the six Republican appointees signed a letter criticizing Democratic candidate Gerald L. Baliles for his stand on teacher pay, alleging he wanted to take away local control of school budgets.

Baliles defeated Durrette by strong margins statewide, including in Northern Virginia.

Collier, who was appointed by Republican Supervisor Nancy Falck, said DuVal is letting politics stand in the way of education.

"To not come to a dinner because you didn't support the candidate is, I think, incredible," she said. "He's setting the precedent -- to say that we will not talk to School Board members who do not vote the way we want them to vote."

A spokesman for DuVal said yesterday that he would have no further comment on the letter.

Collier said DuVal "is allowing politics to interfere with serving the children of Fairfax County."