Democratic gubernatorial nominee Henry E. Howell said yesterday the state income tax structure would be "fairer" if the wealthy paid higher rates, but added that he is not advocating such a tax increase, despite Republican charges to the contrary.

Howell has promised to oppose any "general tax increase" during the next four years, but he said yesterday that an increase in the income tax rate paid by the wealthy would not be a "general" tax increase.

Howell insisted after a Reston speech yesterday that this does not represent a retreat from his opposition to new state taxes. "I want to make it clear," he told reporters at the Sheraton International Conference Center. "I am not suggesting any increase in any tax.

"I do not oppose a progressive income tax that would make the burden fairer," Howell said, but he refused to define precisely what he meant by that. Any initiative to boost income taxes in Virginia will have to come from the state legislature and from a committee that historically has been reluctant to boost income taxes, Howell said.

The dispute stems from an interview published April 18 in Norfolk and Roanoke newspapers in which Howell was quoted as saying he "certainly would" favor restructuring the state income tax above the current ceiling of 5 3/4 per cent on taxable income of $12,000 or more. Speaking in Roanoke yesterday afternoon, Howell said he was speaking of the need for new taxes only in the event of an "emergency or a calamity."

Howell's Republican opponent, Lt. John N. Dalton, charges Wednesday that affluent Northern Virginians would "get clobbered" by new taxes under Howell. In Reston to speak to the same group Howell addressed, Dalton said, "I don't see how you can say when you're raising the income tax, one of the state's major tax sources, that that's not a general tax increase," Dalton said. "I don't see how you can call it a restructuring; it's a general tax increase."

The tax issue could be a decisive one in the Washington suburbs, both Howell and Dalton have acknowledges. The region is the most affluent region in Viriginia and it is and area both men have described as crucial to their campaigns for governor.

According to a recently published survey of 1975 Virginia state tax returns, the upper 9.9 per cent of those filing returns had adjusted gross incomes of $25,000 or more. Those people accounted for 27.9 per cent of the Fairfax County residents filing returns, 17.7 per cent of those from Arlington and 14.2 per cent of those from Alexandria.

Dalton, who also has announced his opposition to new taxes, has said he intends to make Howell's position a major issue in the race. Indeed, raised it a second time yesterday, in a speech to a state realtor's meeting in Roanoke.

Howell, in turn, charged yesterday that Dalton was attempting to distort his tax position in an effort "to scare the people up here in Northern Viriginia."

Howell said that any adjustment in the state's income tax brackets would be up to the General Assembly and that he was not about to suggest what income brackets should be more heavily taxed. Nevertheless, at various times during the day he sugessted income figures under which a family would be immune from higher taxes.

At one point he promised to avoid new taxes on people earning less than $15,000 a year. At another point he said families earning $20,000 or less should be immune from higher tax rates, if imposed, would have to be placed (only) on the "upper 10 per cent."

Howell said he would veto any attempt to boost state income taxes on families that make $15,000 a year or less, along with any effort to boost the state's sales tax or impose a tax on less, along with any effort to noost the newly mined coal.

While Dalton has said that he, too, opposes any new taxes, he has not made the same broad promise to veto tax measures as Howell. In a report published by his own campaign, a Dalton tax adviser suggest that "sooner or later" Virginia is going to have to impose a more progessive income tax schedule a position that Dalton noted yesterday he has not adopted in the current campaign.

Earlier in his speech to school administrators Howell said he would postpone the effective date of various state education standards, if necessary. That position and support for collective bargaining for public employees caused Howell to receive a chilly reception from the 250 school board members and administrators at the Reston hotel.