Over the decades, Americana has provided the Broadway musical comedy with some of its most popular and durable fare. Consider the present array. The roster includes such entertainments as ''A Chorus Line'' and ''Annie,'' ''42nd Street'' and ''Woman of the Year'' (now starring Raquel Welch), ''Dreamgirls,'' ''Sophisticated Ladies,'' and ''Pump Boys and Dinettes.''
A considerable list could be compiled of musicals with a 1,000-plus performance record that have celebrated American ways of life. They range from ''Damn Yankees'' to ''Hello, Dolly!'' and from ''The Pajama Game'' to ''The Music Man'' and ''The Wiz.''
Needless to say, the pursuit of happiness along indigenous folkways is no guarantee of success. It's not enough just to want to hear America singing. Songs worth singing require lyrical gifts worth applauding. To paraphrase computerese: mediocrity in, mediocrity out. Proofs are accumulating in this very young season. Broadway's partiality toward native subject matter has proved but scantily rewarding.
Early arrivals have been nothing if not determinedly American. The callow mock-romancing of ''Cleavage'' gave off a whiff of the Deep South from which it originated - though regrettably not a whiff of magnolias or jasmine. The rambling ''Play Me a Country Song'' saluted in country-and-western idiom the demise of a Colorado truck-stop eatery. ''Seven Brides for Seven Brothers'' starred Debby Boone in a hybrid version of the 1954 M-G-M musical about a spunky waitress who marries a Pacific Northwest frontiersman of the 1850s, then proceeds to tame and civilize his ruffian siblings. Even Miss Boone's charm, cheerful presence, and pleasing vocalism, plus some first-rate dancing, couldn't save the show from its own inadequacies.
Although it had toured successfully since last December, ''Seven Brides'' quit the Broadway scene after only a few performances. The two other early entries folded even faster. All three shows received a negative critical verdict from the New York media.
For some pleasanter news of musicals and Americana, ''A Chorus Line'' recently overtook ''Hello, Dolly!'' to become the fifth-longest-running show in Broadway history. Weekly Variety noticed the landmark by enumerating the 12 leading marathon hits and their performance totals (see below for details).
Not surprisingly, nine of the golden dozen are musicals. Five of the nine - ''Grease,'' ''A Chorus Line,'' ''Hello, Dolly!,'' ''Oklahoma!,'' and ''Annie'' - are quintessentially American. Dolly, to be sure, was a naturalized citizen of Anglo-Austrian ancestry. But when the waiters at the Harmonia Gardens Restaurant finished their chorally exuberant welcome of the wily widow, there wasn't a shred of doubt where Dolly Levi belonged.
If there is a recurring common denominator among these Broadway musical versions of Americana, it is the element of nostalgia. There is an irresistible appeal in the sentimentally comic treatment of what seems nowadays like a more innocent past. The appeal persists, whether we are watching music-man ''Professor'' Harold Hill con the Midwestern provincials of bygone River City, or thrilling to the achievement of statehood by Oklahoma, or having depression-era Annie's faith in ''Tomorrow'' vindicated.
For Broadway itself, tomorrow is always a day and a plan away. According to a theatrical industry trade sheet, there are more than 30 musicals with American themes in various stages of hopeful preparation. Herewith a few of the real or imaginary folk heroes and heroines who may be coming alive on local stages in the months ahead: Orphan Annie (of ''Annie II''), Junius and Edwin Booth, John Henry, George Washington Carver, Charlie Chaplin, Dennis the Menace, Lillie Hitchcock Coit (San Francisco's first firewoman), Ernest Hemingway, Louis Armstrong, Wyatt Earp and family, and the brothers Shubert.
As to the Variety compilation mentioned earlier, the Broadway long-distance runners and their performances (as of the weekend of June 26-27) were listed as follows: ''Grease'' (3,388), ''Fiddler on the Roof'' (3,242), ''Life With Father'' (3,224), ''Tobacco Road'' (3,182), ''A Chorus Line'' (2,850), ''Hello, Dolly!'' (2,844), ''My Fair Lady'' (2,717), ''Oh! Calcutta!'' (2,427), ''Man of La Mancha'' (2,328), ''Abie's Irish Rose'' (2,327), ''Oklahoma!'' (2,212), ''Annie'' (2,152). (Since ''A Chorus Line'' and ''Annie'' are still running, they may yet move ahead in the Broadway marathon.)