WASHINGTON (AP) _ Investors from Texas and California want Congress to pass legislation curbing abuses in limited partnership consolidations known as roll-ups, but one industry group is urging a go-slow policy.

The National Association of Securities Dealers asked a House subcommittee Wednesday to delay passing a bill until it can gauge the effectiveness of new rules it has adopted to protect investors caught up in roll-ups.

However state regulators and investors, testifying before the House telecommunications and finance subcommittee, urged quick passage of roll-up reform.

Bruce Wertz, an investment adviser from the Dallas suburb of Hurst, Texas called roll-ups a ''legal form of theft.''

He estimated that $250,000 he and his clients had invested in a limited partnership was now worth less than eight cents on the dollar.

Roll-ups are shares in limited partnerships repackaged into a new financial product and traded publicly like a stock.

They are under fire because of incidents in which the value of a partnership is diluted when it is consolidated or rolled-up with poorly performing investments by the general partner.

''We need to ban all roll-up practices. The need for protective legislation is now,'' said Eleanor Foerster, a retired educator from Porterville, Calif.

Foerster told the panel, chaired by Rep. Edward Markey, D-Mass., that despite careful research she saw her family's $120,000 investment in a real estate limited partnership shrink to $30,000 after it was rolled-up with less profitable partnerships.

The North American Securities Administrators Association, a state-level securities regulators group, also urged swift passage of a reform bill.

Legislation to curb roll-up abuses cleared the House last year, but died in the Senate.

Markey, Rep. Jack Fields, the ranking Republican on the subcommittee, and others have reintroduced similar legislation that would widen the amount of information roll-up sponsors must disclose to investors, give investors financial alternatives to a roll-up if they oppose it and require assessments of the roll-up's fairness by independent analysts.

But the NASD's Philip Cottone urged lawmakers to wait until the NASD can assess the impact of roll-up reforms it plans to impose on its members.

The NASD, with 5,200 member firms, is a self-regulating organization empowered by Congress to oversee the over-the-counter market for securities generally not traded on stock exchanges.

Late last year, the NASD approved changes that would make it tougher for its affiliated stock brokers to participate in roll-ups and for securities created from roll-ups to list on the NASD's electronic stock market, the Nasdaq National Market System.

Limited partnerships are investment vehicles, usually sold through brokerage firms, in which investors put up between $5,000 and $10,000. The money often goes towards real estate or oil and natural gas drilling projects. Such investments often are earmarked for retirement.

In return, investors receive income, capital gains and tax benefits. But limited partners often found in the past that their investments' value was cut after being ''rolled-up'' with less healthy partnerships.

NASD members cannot participate in a roll-up and roll-up securities could not be listed on the Nasdaq market unless they give investors alternatives like a right to receive compensation based on an appraisal of the rolled-up partnership's assets, under the rules.

The rules change is still subject to approval by the Securities and Exchange Commission, which regulates the securities markets.