A Virginia Board of Corrections committee today warned of continuing security problems at the troubled Mecklenburg prison, saying that management practices throughout the state's prison system were seriously flawed.

Despite some improvements made since the May 31 breakout of six death-row inmates from the maximum security prison near Boydton and subsequent prisoner disturbances there, "consistency in adherence to established procedures remains a problem," according to the report delivered today to Gov. Charles S. Robb.

The report also sharply rebuked prison officials, including Department of Corrections Director Robert M. Landon, who have complained that many of the prison's problems stem from a 1983 agreement on prisoner rights between the state and the American Civil Liberties Union.

"The problem is not one of the terms of the agreement . . . . " the report said, since corrections officials never fully explained the plan to lower level staff members, whose morale was seriously affected by false rumors about it.

The committee, formed by the Board of Corrections, made nearly 60 recommendations, including urging tougher security and better training and higher salaries for guards. It urged that the full corrections board be briefed monthly on security improvements and efforts to implement the ACLU agreement.

Board members found incidents of inmates and guards verbally and physically abusing each other, according to the report, which recommended that both be quickly and strongly punished.

However, it said complaints of brutality by the guards were "neither a frequent nor substantial problem."

Corrections Board Chairman and panel member John W. (Billy) Williams of Charlottesville said the panel did not determine how much its recommendations might cost. The Robb administration is considering using part of the state's more than $100 million surplus to increase spending on the department.

Today's report, more than 270 pages, was the latest in a series of critical reports on the Department of Corrections in the wake of disturbances at Mecklenburg, including a hostage takeover in August. The prison's problems and the criticism they sparked became one of the most serious problems faced by Robb during his three years in office.

The major findings of the five-member panel confirmed the results of other studies that showed little communication among guards and supervisors or between top prison officials around the state and department headquarters in Richmond.

"More appropriate and effective management controls throughout the department may have prevented the recent incidents" at Mecklenburg, the report said.

The prison problems, which have drawn criticism from Republicans and some Democrats in the state legislature, have prompted informed speculation that Landon's job as corrections director may be in jeopardy.

George M. Stoddart, the governor's press secretary, said today that Robb previously had expressed full confidence in Landon and that "his position has not changed." Landon was not available for comment.

Stoddart said Robb had been briefed but had not read the full report. He said the governor characterized it as a "very thorough and good investigation" that proposed long-term solutions to problems that had been years in the making.

Alvin Bronstein, director of the ACLU's National Prison Project, which has been critical of the state's prison system for several years, said the report by the board's own committee "is a clear finding . . . that the problems at Mecklenburg go beyond Mecklenburg and that the central office and director in Richmond are in substantial part responsible for breakdowns there."

The ACLU is preparing to go into court again to force the state to comply with the 1983 agreement, Bronstein said.

Since the breakout last May, the largest such escape from a death row in U.S. prison history, inmates at the 360-bed prison have been mostly kept in "lock-down" conditions that limit their activities.