House and Senate farm conferees decided yesterday to resurrect sugar price supports, but a leading foe of the program threatened in turn to torpedo the entire new farm bill when it returns to the House.

Although the House version of the farm legislation contained no sugar program, it was forgone that the conferees would take care of domestic cane and beet sugar producers.

The conferees adopted the Senate approach--a support loan level of 18 cents a pound, increasing by half a cent annually over the four-year life of the bill.

The sugar issue, as always, was sticky this year, made all the more so by President Reagan's agreement to support a program in return for southern Democratic votes on his budget legislation.

Consumerists persuaded the House to eliminate the sugar program from the farm bill last month, arguing that it would cost consumers more than $2 billion a year. Industry contended it would go bankrupt without federal supports.

The same arguments were heard again yesterday, but this time Rep. Peter A. Peyser (D-N.Y.), a conferee who led the floor fight against sugar, promised to work to scuttle the whole package covering commodities from milk and rice to wheat and cotton if it also helped sugar.

"If sugar remains in the conference report," he said, "you'll put together a coalition that will defeat this conference report . . . given the coalition we will put together, we will defeat this package."

Peyser's threat added fireworks to a grumpy session as the conferees rumbled through another round of posturing, deadlocking and legislative chicken-playing that would have made Col. Sanders proud.

The day began with Sen. Jesse Helms (R-N.C.), conference chairman, threatening to adjourn the conference if members did not get down to brass tacks on the dairy issue that had stalemated them Wednesday.

"We can play one-upsmanship. We can play with our friends who lobby, but they are not helping our farm bill," Helms said. "It would be a disaster for all commodity groups if we don't have a farm bill."

The conferees seemed a bit jolted, and they made half a dozen efforts to come up with a dairy compromise suitable to House, Senate and White House.

But none of the approaches worked as the House delegates, with Rep. Tom Harkin (D-Iowa) quarterbacking their fight, were just as adamant as the Senate's in refusing to give ground.

The House dairy support version is not suitable to the administration because, according to the Department of Agriculture, it would cost some $600 million more than the Senate approach.

The conferees argued for hours over different proposals, but wound up essentially where they began --without an agreement and with each side waiting for the other to blink.

Harkin and his allies contended that dairy farmers, bearing the brunt of the administration's budget-cutting assault, could not afford to have a support program any less generous than the House plan.

The conference, however, approved some details of cotton, grain and rice support programs, but postponed until later the hard decisions on controversial support loan and target price rates, where the Senate and House bills are far apart.

But patience was wearing thin and Sen. Walter D. Huddleston (D-Ky.) said he was tiring of veto threats from the White House and, more lately, Peyser's threat to scuttle the entire farm bill.

"With all these restraints," he said, "I'm getting to feel like the admiral and say damn the torpedoes, full speed ahead."

The conferees are scheduled to try again today.