Folksingers Arlo Guthrie and Joni Mitchell make the Sounds of Summer scene at tonight on Channel 10 in a two-hour color program. It will feature highlights from their concert at the Mississippi River Festival plus an interview with the young performers.

Arlo Guthrie, author of the recent hit recording, "Alice's Restaurant," and son of the immortal Woody Guthrie, is one of the most popular folksingers today. Like Joni Mitchell, he writes most of his own material, and his songs are included in the folksong repertory.

An attractive 24-year-old blond, Canadian-born Joni Mitchell has written more than 60 songs, including "Chelsea Morning" and "Both Sides Now." Her songs have been compared to Bob Dylan's for their "richness and profusion of imagery," and she has acclaimed for her pure vocal delivery.

Joni Mitchell and Arlo Guthrie were recorded for the National Education Television program at a concert given during the premiere season of the Mississippi River Festival. This new annual musical event takes place on the campus of Southern Illinois University at Edwardsville, the summer home of the St Louis Symphony Orchestra. The festival features orchestral concerts and performances by leading pop, rock, and Steve Allen is host.