The Eastern Rugby Union of America, which is sponsoring next month's controversial U.S. tour by the South African Springbok rugby team, accepted a $25,000 donation from a Johannesburg businessman who has previously served as a conduit for secret South African government funds.

The donation was made in December, the same month that the American rugby union issued an invitation to South Africa's Springboks. Because of that country's racial policies; South Africa has been barred from the Olympics and most international sports competition, and no national South African sports team has visited the United States since 1978.

The Springboks are scheduled to play three mid-September matches in Chicago, Albany, N.Y., and New York City following a turbulent six-week tour of New Zealand marked by large and sometimes violent anti-apartheid demonstrations.

If the U.S. matches take place, they are expected to draw similar protests. They will also dim the hopes of the U.S. Olympics Committee, host of the 1984 Games in Los Angeles, for a grand American return to Olympic competition after the 1980 Moscow boycott. African nations, which stayed away from the Montreal Olympics in 1976 to protest New Zealand's sports ties with South Africa, have said the U.S. tour would force them into another boycott in 1984.

U.S. Olympic Committee President William Simon has appealed to the rugby union to cancel the tour, but he has no jurisdiction, since rugby is not an Olympic sport. New York Mayor Edward Koch has withdrawn permission for a Sept. 26 match in a city-owned stadium, and local organizers in Chicago have moved the game to a private facility. But the rugby groups says it will go ahead with play in each city.

According to Eastern Rubgy Union documents, the $25,000 grant in December was provided by Louis Luyt, chairman and chief executive officer of the South Africa-based company Triomf Fertilizer, "for upgrading coaching/referring the ERU." Luyt confirmed the grant in a statement to Washington Post correspondent Caryle Murphy in Johannesburg today, and asserted that there was nothing improper about the donation.

Richard Lapchick, one of the organizers of the Stop Apartheid Rugby Tour Coalition, which received the documents from dissident rugby union members, believes the Luyt contribution is "part of a major South African effort to use money to break the international sports boycott." He cites large purses being offered to American boxers, golfers and other athletes for competing in South Africa.

The coalition describes itself as being composed of nearly 100 religious, sports, civil rights and other American groups opposed to South Africa's rigid system of racial segregation, known as apartheid.

The donor, Luyt, was a key player in the worldwide South African public relations drive that produced a scandal in the late 1970s. The operation used secret Information Department funds to buy influence, both at home and abroad, until press exposes uncovered the story, forcing former prime minister John Vorster and his chosen successor from office.

Official inquiries at the time identified Luyt as conduit for about $15 million in secret funds for The Citizen, a progovernment English language newspaper he established in 1976.

Luyt said in Johannesburg that he provided the $25,000 from his personal funds at the request of the U.S. rugby group's president, Tom Selfridge. He said the money has already been spent, and therefore will not be used for the Springboks' tour.

Luyt said the grant "doesn't make a dent" in the Eastern Rugby Union's expenses. He said he made the donation because South Africans "want more rugby playing countries" and the sport is not yet popular in the United States. He added, "I've donated more than $2 million to sports in the past two years." Luyt said he plans to come to the United States next month and may do some coaching for the rugby union at that time.

The $25,000 Luyt gave the Eastern Rugby Union amounts to a significant boost in income for the association, whose membership comprises clubs in 23 northeastern and southern states. Treasurer Bill Hafner had projected a 1981 budget of $32$350, and in a recent memo on "money" sent to member clubs, reported that "the pains of growth in funding program's [sic] was eased" by the large grant. The 1981 budget figure does not include the grant from Luyt, according to Tom Selfridge, the rugby union president.

Hafner said in a telephone interview that an effort to solicit financial support for the Springbok tour from U.S. corporations with South African subsidiaries had "brought in nothing," despite an appeal letter from Selfridge arguing that "your company will benefit from this support in the South African community."

In June, the Mystic River Rugby Club wrote to Selfridge to "express concern" about the "political overtones" associated with the tour. The Massachusetts club also asked "who from South Africa" had made the gift and "what is the connection between the donation and the South African tour?"

Selfridge named Luyt in his June 26 reply, but denied that the money was a factor in deciding to invite the Springboks. Selfridge also said that Luyt's grant had been disclosed at the rugby union's annual meeting in December.

"This is amateur sport at its purest form. We don't feel sports and politics mix at all," Selfridge said in defending the tour. He added that although Springboks is a national team comprising top players from different South African areas, at least five other less prestigious South African teams have toured the United States this year. The Srpingboks, he added, is an integrated team and includes at least one Colored player and one Colored coach.

Asked why the South African decided to give such a grant, Selfridge said: "Dr. Luyt has a corporation in New York City, he is interested in getting involved in the rugby programs in the United States, and he saw fit to give seed money to our coaching program -- that's about as simple as it can be."

Luyt, a former rugby forward himself, has long maintained an interest in South African athletics and helped establish the Committee for Fairness in Sport, another recipient of government funds in the "Infogate" scandal. According to a budget document prepared by the Information Department that surfaced earlier this year, the committee was to receive $175,000 in secret funding in 1978-79.

Luyt was also named in 1976 as one of five millionaire backers of the Club of Ten, an Information Department project that placed pro-South African ads in European and North American newspapers beginning in 1974.

Lapchick argues that the Luyt donation to the rugby union is yet another secret attempt to promote South African interests.

"They could be attempting to sabotage the 1984 Olympics by having this team come here, because in terms of any competitive value there is certainly no advantage for the Springboks to play American teams that are of no high caliber." He suggested that South Africa would like to see the gap between the United States and black African nations widened.