D.C. City Council Chairman Sterling Tucker introduced his version of a real estate tax relief bill yesterday, assuring that the soaring cost of home ownership will be a central issue in this year's mayoral campaign.

Under Tucker's plan, homeowners could defer the payment of real estate taxes that rise beyond a certain amount in one year, and would be required eventually to pay the city only half the taxes that were deferred. The other half would be forgiven.

Tucker was the last of the three front-runners in the mayoral campaign to propose a tax relief measure.

Council member Marion Barry (D-At Large) introduced the first bill last November, followed by Mayor Walter E. Washington - an unannounced but probable candidate - in February. Last week, Barry introduced a revised measure that incorporates his own and some of the mayor's proposals.

The proposals by all three rivals included one identical feature. All would increase the homeowner's tax exemption frm $6,000 to $9,000. This means, for example that a person owning a house valued at $40,000 would pay taxes only on $31,000.

Both Barry and the mayor proposed a two-level tax rate, with commercial property paying on the basis of a $1.83 rate for each $100 of assessed valuation, with residential property dropping to a $1.57 rate. Both also proposed other tax relief for low-income residents.

In a prepared statement, Tucker said his new bill would provide "genuine tax relief (for) . . . homeowners ain all income brackets." He suggested that his rivals were simply "manipulating the arithmetic which only creates the impression of tax relief."

Tucker estimated the taxpayer benefits from his proposal at $5.5 million a year. Barry has estimated the $15.3 million for his program, and the mayor $13.9 million for his.

In Tucker's plan, there would be a fundamental difference in the way of computing the relief provided for homeowning families with incomes under $30,000 and those earning more.

In all instances, taxpayers would have to apply for the benefits. They would not be automatic.

For those earnings less than $30,000, Tucker's bill would permit a real estate taxpayer to defer the dollar amount of the payment of any tax increase of more than 10 percent in a year. If, for example, last year's tax was $800 and this year's tax bill is for $900, the taxpayer would be able to defer that part of the increase above $80, or $20.

For those earning more than $30,000, the bill would permit the deferral of any tax increase that resulted from a home's assessment increase of more than 25 percent in a year. If, for example, last year's assessment was $60,000 and this year's assessment is $80,000, the taxpayer would be able to defer that part of the tax based on any assessment increase above $75,000 or $5,000.

In both instances, half the tax deferments over the years would be owed to the city when the home is sold. The other half would be forgiven.

In general, there would be no tax deferment for homes where assessments were increased because of improvements. An exception would be made where government funds were used in neighborhood-improvement programs.

A spokesmen for Mayor Washington said the mayor had not seen Tucker's proposal, and would not comment.

Within hours after Tucker's proposal was released, Barry issued a five-page critique accusing the council chairman of playing "follow the leader." Barry said Tucker's proposal is "lacking in many respects" and some parts are of doubtful legality, because the owners of similar houses would pay different amounts of taxes.

Barry, who has offered, a tax deferral proposal of his own for lower-income families, said Tucker's refusal to embrace the lower tax rate for homeowners puts Tucker in the same camp as the Metropolitan Washington Board of Trade.

All the proposed tax measures by the three rivals will be considered by the council's finance and revenue committee, which Barry heads. The bill must then be considered by the full council, which Tucker heads. The ultimate bill, to become law, must be signed by Mayor Washington.

In a related development, the mayor signed legislation sponsored by Barry and first introduced by council member David A. Clarke (D-Ward 1) that would tax profits on speculative buying and selling of dwellings.

In doing so, the mayor criticized the council for not providing for any personnel or funds to administer the new measure. He estimated the annual cost of $500,000 a year.

The measure now goes to Congress for its review, a process that will take at least two months. If not vetoed by Congress, the measure will then go into effect.