Center Dennis Maruk will represent the Washington Capitals in the 34th NHL All-Star Game at Capital Centre Tuesday night.

Maruk was one of 17 players added to the teams yesterday by the rival coaches, Al Arbour of the New York Islanders for the Prince of Wales Conference and Glen Sonmor of Minnesota for the Campbell Conference. The first 12 selections for each team were determined by a vote of sportswriters.

Arbour stirred some controversy when he chose his own left wing, John Tonelli, and ignored Washington captain Ryan Walter. Beyond the obvious fact that the game is here and picking Walter would have been a nice gesture, Walter's scoring figures are more impressive than those of Tonelli.

Walter has collected 27 goals and 31 assists to Tonelli's 21 goals and 25 assists. Although Tonelli is plus 12 compared with Walter's minus eight, those ratings tend to be meaningless considering the relative strengths of the teams. "I guess I'll have to try harder next time," said a disappointed Walter, whose contributions to the Capitals transcend the bare statistics.

The other left wing added by Arbour was Philadelphia's Brian Propp, who is enjoying an excellent season--32 goals, 30 assists, plus 12.

Also named to the Wales team were center Keith Acton of Montreal, right wings Blaine Stoughton of Hartford and Ron Duguay of the New York Rangers, and defensemen Barry Beck of the Rangers and Rod Langway of Montreal.

Sonmor had the more difficult task, since his eight additions had to include representatives from six teams ignored in the voting. As a result, some deserving players had to be ignored, such as center Marcel Dionne of Los Angeles and right wing Glenn Anderson of Edmonton.

The Campbell fills included centers Dale Hawerchuk of Winnipeg and Bobby Smith of Minnesota, left wings Brian Sutter of St. Louis and John Ogrodnick of Detroit, right wings Rick Vaive of Toronto and Don Lever of Colorado, and defensemen Harold Snepsts of Vancouver and Pekka Rautakallio of Calgary.

The 17th selection was defenseman Bob Manno of Toronto, named to replace the Leafs' injured Borje Salming.

This will be Maruk's second all-star appearance; he represented Cleveland in the 1978 contest in Buffalo. Maruk is the NHL's No. 3 scorer with 86 points.