In a sharp setback to Cesar Chavez's United Farm Workers National Union, The Supreme Court has cleared the way for Arizona to enforce a law that the UFW had denounced as the "brainchild" of the state's fruit and vegetable growers and more harmful than no law at all.

The law was found by a panel of three federal judges in April 1978 to be "unconstitutional in its entirety," because five key provisions couldn't be separated from the rest of the statute.

But the Supreme Court ruled 9 to 0 Tuesday that the constitutonal requirement that litigation involve a true "case or controversy" hadn't been met by two of the provisions.

One was construed arbitration. The other known as the access provisions, excuses an agricultural employer from supplying a union with any materials, information, time, or facilities to communicate with farm workers.

The court held that two other provisions could be litigated - were "justiciable" - but that the panel should have abstained from adjudicating the federal issues until the Arizona courts had resolved certain important questions of the state law.

One of the provisions was intended to prevent union-instigated consumer boycotts by making it an unfair labor practice for a union to discourage consumers from buying any agricultural product with the use of "dishonest, untruthful and deceptive publicity."

The other provision imposed criminal penalties for violations of the law.

The court was unanimous as to the consumer-publicity provision. But, Justices William J. Brennan Jr. and Thurgood Marshall parted company from the majority as to the criminal penalties.

The court again was unanimous as to the fifth provision, which specified procedures for the election of employe-bargaining representatives.

In the opinion for th court, Justice Byron R. White wrote that this was the only provision that was properly before the panel.

The panel concluded that the election scheme severly curtailed employes' freedom of association rights under the first Amendment with various delays and technical limitations on who may vote in unit elections.

But even if the scheme allows workers to compel their employers to negotiate in "an assertedly niggardly fashion," White said, the complaint is one "for the Arizona Legislature and not the federal courts."

The decision is expected to influence efforts being made in other states to make it nearly impossible for the UFW to organize.

Arizona has between 30,000 and 40,000 farm workers, most of them migrants. The National Labor Relations Act doesn't cover farm workers.

Under the state law, the UFW says, workers and unions covered by it petitioned for only seven elections in five years. By contrast, under a California farm-worker law they petitioned for nearly 400 elections in the first five months following enactment.

In the decision for the unanimous panel, Judge C. A. Muecke wrote that it prevents the workers from organizing "to exercise their right of freedom of speech and assembly" under the First Amendment. Together with other provisions, he said, this results in "a complete perversion" of the intent claimed by the legislature in enacting the law.