Gov. Bob McDonnell (R) signed amendments to the state’s two-year $78 billion budget Monday, but reduced taxpayer funding for public broadcasting, his office announced Tuesday afternoon.

McDonnell made one line-item veto — reducing by $424,001 the funding for educational programming for public radio and TV stations in fiscal year 2012 — a 25 percent cut.

“In today’s free market, with hundreds of radio and television programs, government should not be subsidizing one particular group of stations,’’ McDonnell said in a statement.

“We must get serious about government spending. That means funding our core functions well, and eliminating spending on programs and services that should be left to the private sector. This is a smart, practical budgeting decision to make Virginia government smaller and more efficient and save taxpayer dollars.”

The Democratic-led Senate had already agreed to reduce station grants by 50 percent in a compromise with the Republican-controlled House of Delegates.

“It’s unfortunate,” Sen. Majority Leader Dick Saslaw (D-Fairfax) said of McDonnell’s decision. “The will of the General Assembly was to keep it going.”

Senate Democratic Caucus Chairwoman Mary Margaret Whipple (D-Arlington) called McDonnell’s veto “most unfortunate,” noting that the line-item action is “seldom used” at this point in the budget process and that the money was cut from a portion of public broadcasting funding that is for public school teacher development and television programming used directly in schools.

“To me, it’s very surprising that he was persistent on this for so long,” she said. “To think that out of all the things in the budget, that this was the one that was so galling to him — that we would actually help children in schools — that he would veto it, I find it mind-boggling.”

Saslaw predicted the impact on public radio and television stations will be “pretty severe.”

“It penalizes a lot of the children’s programming that, particularly in rural areas, that is a part of the educational system,” he said.

This post has been updated since it was first published.