Violence against working drivers appeared to be decreasing as the independent truckers' strike neared the end of its first week yesterday without having succeeded in significantly disrupting the flow of goods.

Government officials said there had been no major supply problems nationally since the strike began at midnight last Sunday, despite spot shortages in vegetables and fresh fruits in New York, Boston and Philadelphia and a few delayed industrial shipments in Ohio, Indiana and Illinois.

Officials were not claiming victory, because if the strike picks up in the second week, major shortages could appear. Further, many truck stops around the country said traffic was down sharply from a normal Saturday.

"We'll be out of business here, I'd say Tuesday or Wednesday, unless we can get supplies somewhere," Al Bachman, a wholesale produce distributor in Pittsburgh, told United Press International.

Independent Truckers Association President Mike Parkhurst had predicted serious effects in "four or five days," which did not occur, but an ITA spokesman said yesterday, "We expect results to be more evident by the end of next week."

More than 1,000 sniper or rock-throwing incidents against truckers have been reported nationally since the strike began, and a North Carolina trucker was shot and killed. At least 90 people have been arrested, some of them identified as truckers, as states have intensified patrols.

Off-duty prison guards checked overpasses in Oklahoma; game wardens patrolled roads in Maine; National Guard helicopters hovered over North Carolina highways, and Pennsylvania state police watched the turnpike and Interstate 80.

Pennsylvania has had the most serious problems with more than 370 incidents, but the count dropped sharply yesterday. "We're up to 24 arrests and that word is getting out," said William J. Green, a spokesman for the Pennsylvania governor's office.

In Ohio, which also has had major problems, only 17 incidents were reported Friday night compared with more than 80 Thursday night, state police said.

The timing of the strike, according to transportation experts, could not have been worse for it to succeed economically. Literally thousands of unneeded railroads cars are in storage and the trucking industry is estimated to have as much as 40 percent more capacity than needed.

Because of deregulation in both the railroad and trucking industries, it is easier than it was three years ago for a shipper to switch from truck to rail or to a "piggyback" combination, in which a truck-tractor hauls a trailer from a plant to a rail terminal, the railroad carries it hundreds of miles on a flatcar, and another tractor picks it up.

Since the passage of railroad deregulation in 1980, railroads have increased their share of fresh fruits and vegetables from 9.6 percent of the market to 11.7 percent, according to the Association of American Railroads. Piggyback shipments of produce have jumped from 1 percent of the railroad share to 4.74 percent. There were early indications last week of significant additional shifts from truck to rail of fresh fruit and vegetables, a Transportation Department source said.

"If this went on for a month, we'd be delighted from a competitive point of view," a railroad official said.

Independent truckers who launched similar protests against diesel fuel prices in 1974 and 1979 where able to force auto plants to close for lack of parts. According to the department, there have been no such disruptions this time.

Steel industry shippers have told department officials that they have shifted substantial freight to rail and are suffering no damage. One western railroad told them it has enjoyed a 25 percent increase in the past week; an eastern railroad noted a 40 percent increase in piggyback loads.

The large number of trucks available also means that many truckers will haul loads others decline to carry, whether out of fear of reprisal or in genuine protest.

"Eventually other truckers will move in," said Edward V. Kiley, senior vice president of the American Trucking Associations, which represents the major trucking companies and is not supporting the strike. "Trucks are looking for cargo; this is no time for somebody to walk out."

Yesterday, Sen. Robert J. Dole (R-Kan.), chairman of the Senate Finance Committee that helped write the truck taxes, asked the General Accounting Office to study the taxes' economic impact. He feels they are fair, he said, but "most law-abiding truckers would like to get back to work" and he thought a study might help.

He also said he will seek legislation making it possible for the federal government to seek court orders enjoining people from encouraging violence that would interfere with commerce. Dole called Parkhurst a "troublemaker."

He said he "would be happy" to discuss his proposals with Elizabeth Hanford Dole, his wife, who is scheduled to be sworn in as transportation secretary on Monday, but has not done so.