RONALD REAGAN may have come to Washington determined to get the government off the people's backs, but out in Iowa there is an example of government at its best -- government that works, that is immediately responsive, that in many cases anticipates problems and is capable of quickly focusing the intellectual, technological and financial resources of the state on them.

It is, in a word, the kind of government the people want and used to expect, but lately haven't been getting in a great many cases, which has had a lot to do with Reagan's political success.

It is the Iowa County Cooperative Extension Service, which for most of the 20th century has operated a wide variety of educational, research and technical programs that have helped make American farmers productive beyond anyone's reasonable expectations. Traditionally, it has helped farmers cope with drought, flood, corn borers and erosion and to keep track of new strains of seeds, feeds and a thousand other factors.

Now, out of necessity, the service has turned its resources to helping farmers cope -- emotionally and financially -- with the worst agriculture crisis since the Great Depression.

The seriousness of that crisis was tragically underscored last week in Hills, Iowa, when a despairing farmer -- who was not working with his county extension service in any of its programs -- killed his wife, his neighbor, his banker and then himself because of the seeming hopelessness of his financial troubles. But the crisis permeates every farm and town in the country's farm belt.

When the bank in the small farming town of Odebolt, Iowa (pop. 1,300), went belly-up earlier this year, the emotional stress level of many farmers and townspeople, already running high because of the on-going agriculture economy crisis, nearly went off the charts.

From his counseling with his parishioners, the Rev. Tom Hotle of the United Methodist Church in Odebolt quickly determined that the need for help was community-wide. He turned for assistance to the Sac County Cooperative Extension Service in forming personal support groups for people who needed help with their problems.

The extension service responded immediately, indeed eagerly, because it already had such a program in place known as "Neighbor to Neighbor." It provided psychological and counseling experts from Iowa State University and its regional office in Sioux City to train the local clergymen in setting up the support groups, plus materials for the groups prepared by the university psychology department. When Hotle and the others need additional assistance, it's likely to be on its way by the time they've hung up the phone.

The impact of its farm-crisis programs, which for the most part have been operating in Sac County in just the past few months, already are noticeable.

The morale of the Odebolt community, which bottomed out last summer after the bank and nearly a dozen other main street businesses closed, is improved -- for psychological as well as technical reasons. It may be that the major benefit of the programs is that, in effect, they are road maps that help re-orient people who are angry, frightened and overwhelmed by the prospect of economic disaster that they never dreamed could happen to them. The programs define the people's problems and give most the feeling that there's something they can do about them.

The extension service is also a working example of federalism. It gets state and local funding plus federal funds and other resources from the Department of Agriculture. The money is channeled through Iowa State University, a land-grant school that makes its faculty and other resources available, and the programs are coordinated by the university's dean of extension.

It is a decentralized program, however. The extension service responds to local circumstances and demands outlined by local citizens' committees. The result is a remarkably flexible and responsive government agency that can move quickly without bureaucratic hang-ups.

In addition to the personal support groups -- which also encourage and train participants to form other such groups to help friends and relatives -- the extension service responded quickly when two school girls in Odebolt attempted suicide a couple of years ago. The university provided instructors and video tapes for teachers, clergymen, doctors, nurses, leaders of 4H and other youth groups, service clubs and anyone else who was interested in recognizing and dealing with signs of stress in young people and how to handle suicide threats and attempts.

The county agent is crucial to the program and Sac County is well served by its agent, Floyd Schnirring. A farmer himself, he was hospitalized recently because of the stress he was feeling for what he refers to as "his" farmers. "I'd really hate to lose him," he says of a farmer in trouble.

An increasingly popular program is the Farm Aid computer analysis of farmers' operations, which breaks them down into their separate parts -- corn, cattle, hogs, etc. -- and shows them which are weak and could be strengthened, which are good and which should be dropped.

Between 15 percent and 20 percent of the county's farmers have undergone this analysis -- about 30 more in just the past three weeks -- and many who did it a year ago are coming back for an update. Many are learning that they have been great producers but careless and sloppy businessmen; but the greatest benefit may simply be the restoration of the farmer's morale by showing him how he can help himself.

As valuable as the extension service has been to farmers, however, the greatest beneficiary is the American consumer. Te service's harnessing of science and technology in this century has been a major factor in the nation's enormous farm productivity -- and resulting cheap food prices.