Maryland's upcoming thoroughbred racing meeting, expected to have a jazzy new theme, instead will echo a strained, discordant note for track owners, horsemen and thousands of District-area racegoers when Pimlico reopens Tuesday.

The 33-day meet was to have featured a first for Maryland racing: intertrack wagering. Under the experimental system, fans at Laurel's Sports Palace would have watched races simulcast from Pimlico, their bets tied in with those at the Baltimore track.

The request initially was approved by a state committee, 8-7. However, because of a voting impropriety, one vote in favor of the proposal was rescinded and the measure defeated.

Frank De Francis, principal owner of Laurel and Pimlico, said last week he accepted the ruling "without any acrimony, without any bitterness." But he clearly was troubled by questions.

"I still wonder: 'Why did an issue so basic, so simple, go down to defeat?' " De Francis asked. "Who caused it? Who profited by it? . . . Certainly, not the people of Montgomery County, or Prince George's, or Frederick, or Washington, D.C., or Northern Virginia, who were denied the right to see . . . racing at Pimlico without having to traverse two beltways and an interstate."

De Francis said the state's ruling eliminated 174 new jobs, cost horsemen an estimated $342,000 in purses and the race tracks $26,000 in net profit. He said the tracks had spent about $20,000 to set up the intertrack betting system.

De Francis said he wanted to try the experiment in the fall, when the Sports Palace's lure is enhanced by baseball playoffs and pro and college football games on large screens. He said he will resubmit the intertrack wagering proposal; if accepted, the system could debut during Pimlico's spring 1988 meeting, but its fall '88 meet is more likely.

"The Pimlico spring meet is not the perfect time," said De Francis, "because obviously the spring sports session is not anywhere near as attractive as the fall season."

One of Maryland racing's major attractions -- the Maryland Million -- will take place during Pimlico's upcoming meeting.

The Sept. 19 nine-race program, designed to promote the state's breeding industry, will offer $1 million in purses to the offspring of eligible Maryland stallions. Featured is the $200,000 Budweiser Maryland Classic, for 3-year-olds and up at 1 1/4 miles.

The USF&G Lassie (for 2-year-old fillies) and the Business Express Maryland Nursery (for 2-year-old males) will be six furlongs -- a quarter-mile shorter than at last year's inaugural Million at Laurel -- because Pimlico lacks a mile chute.

"We considered a mile and sixteenth," said racing secretary Larry Abbundi, "but the horses would have had to go around two turns, and a lot of those 2-year-olds have never been around two turns. It might have caused a lot of horsemen to back off. This way, we have a better chance of drawing fuller fields."

Abbundi said Pimlico will not hold a turf race before Maryland Million day to protect the grass course. Following the Million, Abbundi said, the track will offer at least two turf races for 2-year-old maidens in preparation for the Laurel Futurity and Selima Stakes, Grade I races for 2-year-olds that will be held on turf for the first time ever, Nov. 1 at Laurel.

The Futurity and Selima will be part of Laurel's "International Weekend." The Washington, D.C. International will be held Oct. 31.

The $75,000-added Northern Dancer Stakes for 3-year-olds will underscore Tuesday's opening-day card at Pimlico. Hay Halo, fifth to Polish Navy in Saratoga's sloppy Jim Dandy Stakes last month, is the overnight favorite in the six-horse, 1 1/8-mile race; however, in his last three stakes longer than seven furlongs, Hay Halo has finished second once, fifth twice.

Hay Halo's chief competitor is expected to be Green Book, who has earned a race-high $109,879 in 1987. Prolinage, Grand Rol, Ringing and Mystic Wars complete the field.

First-race post time is 1 p.m.