Bananas, as one industry expert points out, are not one of the world's most indispensible products: "To West Germany, to the United States, if there are no bananas in a given year, it's no big deal."

But to the handful of Central American nations where most of the world's bananas are grown, a bad year in the banana business can mean disaster to tens of thousands of plantation laborers and to their national economies.

Despite the fact that the banana industry is among the largest employers and money earners in Panama, Costa Rica, Honduras and Guatemala, the governments and farmers of these nations have practically no bananas to call their own. United Brands has bananas. Del Monte and Standard Fruit (Dole) have bananas.

The Central American banana business begins and ends in the hands of U.S. multi-national companies.

Traditionally, the companies have owned the bananas and the profits they bring, the land on which they grow, the ports from which the bananas are shipped and the boats they are shipped on. The companies set the prices and regulate the supply in banana importing countries.

To gain more control over the industry which is vital to their economies - the four Central American producing countries, along with Colombia and the Dominican Republic, recently formed their own banana exporting and marketing organization, called COMUNBANA. With an eye toward eventual competition with the multinationals, COMUNBANA last month exported its first multinationals. COMUNBANA last month exported its first 40,000 tons of fruit, from Panama to Yugoslavia.

Since United Brands (formerly United Fruit), up to now the sole exporter here, expects to ship at least 714,000 tons of bananas from Panama alone this year, it is perhaps difficult to understand why the company is upset over its infant competitor.

Yet the subject of COMUNBANA can drive Bobby Walker, a normally taciturn man who runs United Brands' two Panama plantations, to distraction.

COMUNBANA, Walker said recently is, "is going to lose [it's] behind" trying to cash in on the banana trade, "and I am going to get the blame." Walker described COMUNBANA director Herman Vallejos as "a snake."

Vallejos, on the other hand, has accused United Brands, and the other multinationals, of waging an "unfair and unjustified" campaign against COMUNBANA, ranging from pressuring independent producers not to sell to the organization, to attempt to overthrow hostile governments.

How the gentle banana, itself so senitive and easily bruised, became involved in such a heated dispute, is a matter of history.

Following its birth here in 1899, United Fruit built the banana business literally from the ground up. Known as La Frutera by Central Americans, the company hired thousands of workers, bought thousands of acres of land and quickly developed not only the actual plantations, but bustling towns, railroads, ports, roads and bridges.

Traditionally, La Frutera was credited with making and breaking governments, often in the name of the United States.

In 1974, during a period that became known as the banana wars," United Brands, the new United Fruit parent company, admitted to having bribed Honduran officials with more than $1.2 million to lower a newly imposed $1 tax on each box of bananas exported.

In another Central American republic where the tax was imposed, a United Nations report noted, "one corporation refused for a while to export bananas, and resorted to destroying 145,000 boxes of fruit."

In the aftermath of the banana war, under heavy pressure from what Vallejos calls the "post-Watergate morality" in the United States, the multinationals cleaned up some of their more blatant anti-union tactics and agreed to sell their land back to the countries and lease the plantations. In return, the Central American countries subsequently lowered the tax, which now averages 43 cents per box.

The Central American nations also joined to form the Union of banana Exporting Countries (UBEC), an information exchange and political pressure group that subsequently gave birth to COMUNBANA, the marketing organization.

"OBEC was not created against the multinationals," said Vallejos, who heads both UBEC and COMUNBANA. "There has never been an attitude against foreign investment, but they have a responsibility to contribute" to the countries in which they operate.

What Vallejos wants United Brands and the others to contribute are a limitation on excessive banana supplies that glut the market, and fair, steady prices.

While the price of bananas has risen steadily since 1973, Vallejos said the countries have no mechanism for increasing their own take, and "the only way to induce" the multinationals to treat them fairly "is to create our own commercial business."

The idea of the banana republics competing with the multinational giants has a certain appeal. But, as Vallejos readily admitted, COMUNBANA has confronted a number of problems.

Aside from a lack of markets and technological know-how, COMUNBANA has no bananas to sell. Two-thirds of the developed banana land in Panama, for example, is run by United Brands on 12,500-acre plantations in Changuinola, on the Atlantic coast and puerto Armuelles, on the Pacific. Most of the other is owned by private producers under contract to United Brands.

In fact COMUNBANA was saved from the last minute embarrassment of having no bananas to fulfil its Yugoslav contract only when the Panamanian government, which operates its own small plantations, agreed to turn over its banana supply to the group.

Vallejos said he is bitter about the multinationals' refusal to assist the struggling organization - with technology, shared marketing information, and bananas.

"We've asked them to help us, to cooperate, and they don't want us to exist."

To Walker of United Brands, even the accumulated guilt of decades of admitted past colonialism is not enough to make him aid a competitor. Besides, he said darkly, he suspects COMUNBANA might be a front for one of the big boys, competitor Standard Fruit.

Standing in the vast silent banana fields of Changuinola where 5,000 Panamanians work at wages that average more than twice the government's minimum hourly wage, he puzzled over how his company has ended up the ostensible bad guy in the current situation.

"We employ 10,000 people in Panama, 99.8 percent of them are Panamanians, and if that's colonialism, I don't know what their problem is."

In addition, he said, United Brands has more capital investment in Panama than any other outside company, and has taken all the production risks for what he said is a mere 30 cents a box profit. The Panamanian government, he noted, now takes 40 cents a box in taxes without lifting a finger.

"The politicians," Walker conceded, "think it's a good political issue."